Climate change in the Arctic

Impacts of climate change on the Arctic

The maps above compare the Arctic ice minimum extents from 2012 (top) and 1984 (bottom). Climate change in the Arctic.pdf

Major environmental issues caused by contemporary climate change in the Arctic region range from the well-known, such as the loss of sea ice or melting of the Greenland ice sheet, to more obscure, but deeply significant issues, such as permafrost thaw,[1] as well as related social consequences for locals and the geopolitical ramifications of these changes.[2] The Arctic is likely to be especially affected by climate change because of the high projected rate of regional warming and associated impacts.[3] Temperature projections for the Arctic region were assessed in 2007:[4] These suggested already averaged warming of about 2 °C to 9 °C by the year 2100. The range reflects different projections made by different climate models, run with different forcing scenarios. Radiative forcing is a measure of the effect of natural and human activities on the climate. Different forcing scenarios reflect things such as different projections of future human greenhouse gas emissions.

These effects are wide-ranging and can be seen in many Arctic systems, from fauna and flora to territorial claims.[2] According to a July 2022 article in Geophysical Research Letters, temperatures in the Arctic region are rising four times as fast as elsewhere on Earth,[5]: 1 [6] leading to these effects worsening year on year and causing significant concern. The changing Arctic has global repercussions, perhaps via ocean circulation changes[7] or arctic amplification.[8]

## Current trends and impacts[edit]

The 2021 Arctic Monitoring and Assessment Programme (AMAP) report by an international team of more than 60 experts, scientists, and indigenous knowledge keepers from Arctic communities, was prepared from 2019 to 2021.[9]: vii It is a follow-up report of the 2017 assessment, "Snow, Water, Ice and Permafrost in the Arctic" (SWIPA).[9]: vii The 2021 IPCC AR6 WG1 Technical Report confirmed that "[o]bserved and projected warming" were ""strongest in the Arctic".[10]: 29 According to an August 11, 2022 article published in Nature, there have been numerous reports that the Arctic is warming from twice to three times as fast as the global average since 1979, but the co-authors cautioned that the recent report of the "four-fold Arctic warming ratio" was potentially an "extremely unlikely event".[11] The annual mean Arctic Amplification (AA) index had "reached values exceeding four" from c. 2002 through 2022, according to a July 2022 article in Geophysical Research Letters.[5]: 1 [6]

The December 14, 2021 16th Arctic Report Card produced by the United States's National Oceanic and Atmospheric Administration (NOAA) and released annually, examined the "interconnected physical, ecological and human components" of the circumpolar Arctic.[12][13] The report said that the 12 months between October 2020 and September 2021 were the "seventh warmest over Arctic land since the record began in 1900".[12] The 2017 report said that the melting ice in the warming Arctic was unprecedented in the past 1500 years.[14][15] NOAA's State of the Arctic Reports, starting in 2006, updates some of the records of the original 2004 and 2005 Arctic Climate Impact Assessment (ACIA) reports by the intergovernmental Arctic Council and the non-governmental International Arctic Science Committee.[16]

A 2022 United Nations Environment Programme (UNEP) report "Spreading Like Wildfire: The Rising Threat Of Extraordinary Landscape Fires" said that smoke from wildfires around the world created a positive feedback loop that is a contributing factor to Arctic melting.[17][18] The 2020 Siberian heatwave was "associated with extensive burning in the Arctic Circle".[17]: 36 Report authors said that this extreme heat event was the first to demonstrate that it would have been "almost impossible" without anthropogenic emissions and climate change.[19][17]: 36

## Impacts on the natural environment[edit]

### Temperature and weather changes[edit]

The image above shows where average air temperatures (October 2010 – September 2011) were up to 2 degrees Celsius above (red) or below (blue) the long-term average (1981–2010).

According to the Intergovernmental Panel on Climate Change, "surface air temperatures (SATs) in the Arctic have warmed at approximately twice the global rate".[20] The period of 1995–2005 was the warmest decade in the Arctic since at least the 17th century, with temperatures 2 °C (3.6 °F) above the 1951–1990 average.[21] In addition, since 2013, Arctic annual mean SAT has been at least 1 °C (1.8 °F) warmer than the 1981-2010 mean. With 2020 having the second warmest SAT anomaly after 2016, being 1.9 °C (3.4 °F) warmer than the 1981–2010 average.[22] In 2016, there were extreme anomalies from January to February with the temperature in the Arctic being estimated to be between 4-5.8 degrees Celsius more than it was between 1981 and 2010, and has shown to not have cooled years followed.[23]

Some regions within the Arctic have warmed even more rapidly, with Alaska and western Canada's temperature rising by 3 to 4 °C (5.40 to 7.20 °F).[24] This warming has been caused not only by the rise in greenhouse gas concentration, but also the deposition of soot on Arctic ice.[25] The smoke from wildfires defined as "brown carbon" also increases arctic warming. Its warming effect is around 30% from the effect of black carbon (soot). As wildfires increases with warming this create a positive feedback loop.[18] A 2013 article published in Geophysical Research Letters has shown that temperatures in the region haven't been as high as they currently are since at least 44,000 years ago and perhaps as long as 120,000 years ago. The authors conclude that "anthropogenic increases in greenhouse gases have led to unprecedented regional warmth."[26][27]

On 20 June 2020, for the first time, a temperature measurement was made inside the Arctic Circle of 38 °C, more than 100 °F. This kind of weather was expected in the region only by 2100. In March, April and May the average temperature in the Arctic was 10 °C higher than normal.[28][29] This heat wave, without human – induced warming, could happen only one time in 80,000 years, according to an attribution study published in July 2020. It is the strongest link of a weather event to anthropogenic climate change that had been ever found, for now.[30] Such heat waves are generally a result of an unusual state of the jet stream.

Some scientists suggest that climate change will slow the jet stream by reducing the difference in temperature between the Arctic and more southern territories, because the Arctic is warming faster. This can facilitate the occurring of such heat waves.[31] The scientists do not know if the 2020 heat wave is the result of such change.[32]

A rise of 1.5 degrees in global temperature from the pre-industrial level will probably change the type of precipitation in the Arctic from snow to rain in summer and autumn, which will increase glaciers melting and permafrost thawing. Both effects lead to more warming.[13]

One of the effects of climate change is a strong increase in the number of lightnings in the Arctic. Lightnings increase the risk for wildfires.[33]

#### Arctic amplification[edit]

This section is an excerpt from Ice–albedo feedback § Current role.[edit]

Albedo change in Greenland from 2000-2006 to 2011. Practically the entire ice sheet became less reflective

Snow– and ice–albedo feedback have a substantial effect on regional temperatures. In particular, the presence of ice cover and sea ice makes the North Pole and the South Pole colder than they would have been without it.[34] Consequently, recent Arctic sea ice decline is one of the primary factors behind the Arctic warming nearly four times faster than the global average since 1979 (the year when continuous satellite readings of the Arctic sea ice began), in a phenomenon known as Arctic amplification.[35]

Modelling studies show that strong Arctic amplification only occurs during the months when significant sea ice loss occurs, and that it largely disappears when the simulated ice cover is held fixed.[36] Conversely, the high stability of ice cover in Antarctica, where the thickness of the East Antarctic ice sheet allows it to rise nearly 4 km above the sea level, means that this continent has experienced very little net warming over the past seven decades, most of which was concentrated in West Antarctica.[37][38][39] Ice loss in the Antarctic and its contribution to sea level rise is instead driven overwhelmingly by the warming of the Southern Ocean, which had absorbed 35–43% of the total heat taken up by all oceans between 1970 and 2017.[40]

Ice–albedo feedback also has a smaller, but still notable effect on the global temperatures. Arctic sea ice decline between 1979 and 2011 is estimated to have been responsible for 0.21 watts per square meter (W/m2) of radiative forcing, which is equivalent to a quarter of radiative forcing from CO2[41] increases over the same period. When compared to cumulative increases in greenhouse gas radiative forcing since the start of the Industrial Revolution, it is equivalent to the estimated 2019 radiative forcing from nitrous oxide (0.21 W/m2), nearly half of 2019 radiative forcing from methane (0.54 W/m2) and 10% of the cumulative CO2 increase (2.16 W/m2).[42] Between 1992 and 2015, this effect was partly offset by the growth in sea ice cover around Antarctica, which produced cooling of about 0.06 W/m2 per decade. However, Antarctic sea ice had also begun to decline afterwards, and the combined role of changes in ice cover between 1992 and 2018 is equivalent to 10% of all the anthropogenic greenhouse gas emissions.[43]

This section is an excerpt from Polar amplification § Recent Arctic amplification.[edit]

The dark ocean surface reflects only 6 percent of incoming solar radiation, while sea ice reflects 50 to 70 percent.[44]

The Arctic was historically described as warming twice as fast as the global average,[45] but this estimate was based on older observations which missed the more recent acceleration. By 2021, enough data was available to show that the Arctic had warmed three times as fast as the globe - 3.1°C between 1971 and 2019, as opposed to the global warming of 1°C over the same period.[46] Moreover, this estimate defines the Arctic as everything above 60th parallel north, or a full third of the Northern Hemisphere: in 2021–2022, it was found that since 1979, the warming within the Arctic Circle itself (above the 66th parallel) has been nearly four times faster than the global average.[47][48] Within the Arctic Circle itself, even greater Arctic amplification occurs in the Barents Sea area, with hotspots around West Spitsbergen Current: weather stations located on its path record decadal warming up to seven times faster than the global average.[49][50] This has fuelled concerns that unlike the rest of the Arctic sea ice, ice cover in the Barents Sea may permanently disappear even around 1.5 degrees of global warming.[51][52]

The acceleration of Arctic amplification has not been linear: a 2022 analysis found that it occurred in two sharp steps, with the former around 1986, and the latter after 2000.[53] The first acceleration is attributed to the increase in anthropogenic radiative forcing in the region, which is in turn likely connected to the reductions in stratospheric sulfur aerosols pollution in Europe in the 1980s in order to combat acid rain. Since sulphate aerosols have a cooling effect, their absence is likely to have increased Arctic temperatures by up to 0.5 degrees Celsius.[54][55] The second acceleration has no known cause,[46] which is why it did not show up in any climate models. It is likely to be an example of multi-decadal natural variability, like the suggested link between Arctic temperatures and Atlantic Multi-decadal Oscillation (AMO),[56] in which case it can be expected to reverse in the future. However, even the first increase in Arctic amplification was only accurately simulated by a fraction of the current CMIP6 models.[53]

#### Black carbon[edit]

Main article: Black carbon

Black carbon deposits (from the combustion of heavy fuel oil (HFO) of Arctic shipping) absorb solar radiation in the atmosphere and strongly reduce the albedo when deposited on snow and ice, thus accelerating the effect of the melting of snow and sea ice.[57] A 2013 study quantified that gas flaring at petroleum extraction sites contributed over 40% of the black carbon deposited in the Arctic.[58][59] Recent studies attributed the majority (56%) of Arctic surface black carbon to emissions from Russia, followed by European emissions, and Asia also being a large source.[60][57]

According to a 2015 study, reductions in black carbon emissions and other minor greenhouse gases, by roughly 60 percent, could cool the Arctic up to 0.2 °C by 2050.[61] However, a 2019 study indicates that "Black carbon emissions will continuously rise due to increased shipping activities", specifically fishing vessels.[62]

### Decline of sea ice[edit]

1870–2009 Northern Hemisphere sea ice extent in million square kilometers. Blue shading indicates the pre-satellite era; data then is less reliable.

This section is an excerpt from Arctic sea ice decline.[edit]

Sea ice in the Arctic region has declined in recent decades in area and volume due to climate change. It has been melting more in summer than it refreezes in winter. Global warming, caused by greenhouse gas forcing is responsible for the decline in Arctic sea ice. The decline of sea ice in the Arctic has been accelerating during the early twenty‐first century, with a decline rate of 4.7% per decade (it has declined over 50% since the first satellite records).[63][64][65] It is also thought that summertime sea ice will cease to exist sometime during the 21st century.[66]

The region is at its warmest in at least 4,000 years[67] and the Arctic-wide melt season has lengthened at a rate of five days per decade (from 1979 to 2013), dominated by a later autumn freeze-up.[68] The IPCC Sixth Assessment Report (2021) stated that Arctic sea ice area will likely drop below 1 million km2 in at least some Septembers before 2050.[69] In September 2020, the US National Snow and Ice Data Center reported that the Arctic sea ice in 2020 had melted to an extent of 3.74 million km2, its second-smallest extent since records began in 1979.[70] Earth lost 28 trillion tonnes of ice between 1994 and 2017, with Arctic sea ice accounting for 7.6 trillion tonnes of this loss. The rate of ice loss has risen by 57% since the 1990s.[71]

#### Changes in extent and area[edit]

Reliable measurement of sea ice edges began with the satellite era in the late 1970s. Before this time, sea ice area and extent were monitored less precisely by a combination of ships, buoys and aircraft.[72] The data show a long-term negative trend in recent years, attributed to global warming, although there is also a considerable amount of variation from year to year.[73] Some of this variation may be related to effects such as the Arctic oscillation, which may itself be related to global warming.[74]

Sea ice coverage in 1980 (bottom) and 2012 (top), as observed by passive microwave sensors from NASA. Multi-year ice is shown in bright white, while average sea ice cover is shown in light blue to milky white.

The rate of the decline in entire Arctic ice coverage is accelerating. From 1979 to 1996, the average per decade decline in entire ice coverage was a 2.2% decline in ice extent and a 3% decline in ice area. For the decade ending 2008, these values have risen to 10.1% and 10.7%, respectively. These are comparable to the September to September loss rates in year-round ice (i.e., perennial ice, which survives throughout the year), which averaged a retreat of 10.2% and 11.4% per decade, respectively, for the period 1979–2007.[75]

The Arctic sea ice September minimum extent (SIE) (i.e., area with at least 15% sea ice coverage) reached new record lows in 2002, 2005, 2007, 2012 (5.32 million km2), 2016 and 2019 (5.65 million km2).[76][77][78] The 2007 melt season let to a minimum 39% below the 1979–2000 average, and for the first time in human memory, the fabled Northwest Passage opened completely.[79] During July 2019 the warmest month in the Arctic was recorded, reaching the lowest SIE (7.5 million km2) and sea ice volume (8900 km3). Setting a decadal trend of SIE decline of −13%.[78] As for now, the SIE has shrink by 50% since the 1970s.[80]

From 2008 to 2011, Arctic sea ice minimum extent was higher than 2007, but it did not return to the levels of previous years.[81][82] In 2012 however, the 2007 record low was broken in late August with three weeks still left in the melt season.[83] It continued to fall, bottoming out on 16 September 2012 at 3.42 million square kilometers (1.32 million square miles), or 760,000 square kilometers (293,000 square miles) below the previous low set on 18 September 2007 and 50% below the 1979–2000 average.[84][85]

Temperatures in the Arctic region are increasing four times faster than elsewhere on Earth, according to a July 2022 Geophysical Research Letters article.[5]: 1 [6]

#### Changes in volume[edit]

Seasonal variation and long-term decrease of Arctic sea ice volume as determined by measurement backed numerical modelling.[86]

The sea ice thickness field and accordingly the ice volume and mass, is much more difficult to determine than the extension. Exact measurements can be made only at a limited number of points. Because of large variations in ice and snow thickness and consistency air- and spaceborne-measurements have to be evaluated carefully. Nevertheless, the studies made support the assumption of a dramatic decline in ice age and thickness.[81] While the Arctic ice area and extent show an accelerating downward trend, arctic ice volume shows an even sharper decline than the ice coverage. Since 1979, the ice volume has shrunk by 80% and in just the past decade the volume declined by 36% in the autumn and 9% in the winter.[87] And currently, 70% of the winter sea ice has turned into seasonal ice.[80]

#### An end to summer sea ice?[edit]

The IPCC's Fourth Assessment Report in 2007 summarized the current state of sea ice projections: "the projected reduction [in global sea ice cover] is accelerated in the Arctic, where some models project summer sea ice cover to disappear entirely in the high-emission A2 scenario in the latter part of the 21st century."[83] However, current climate models frequently underestimate the rate of sea ice retreat.[73] A summertime ice-free Arctic would be unprecedented in recent geologic history, as currently scientific evidence does not indicate an ice-free polar sea anytime in the last 700,000 years.[88][89]

The Arctic ocean will likely be free of summer sea ice before the year 2100, but many different dates have been projected, with models showing near-complete to complete loss in September from 2035 to some time around 2067.[90][91]

#### Melting of the Greenland ice sheet[edit]

Albedo Change on Greenland

Models predict a sea-level contribution of about 5 centimetres (2 in) from melting of the Greenland ice sheet during the 21st century.[92] It is also predicted that Greenland will become warm enough by 2100 to begin an almost complete melt during the next 1,000 years or more.[84][93] In early July 2012, 97% percent of the ice sheet experienced some form of surface melt, including the summits.[94]

Ice thickness measurements from the GRACE satellite indicate that ice mass loss is accelerating. For the period 2002–2009, the rate of loss increased from 137 Gt/yr to 286 Gt/yr, with every year seeing on average 30 gigatonnes more mass lost than in the preceding year.[95] The rate of melting was 4 times higher in 2019 than in 2003. In the year 2019 the melting contributed 2.2 millimeters to sea level rise in just 2 months.[96][97] Overall, the signs are overwhelming that melting is not only occurring, but accelerating year on year.

Greenland ice sheet mass trend (2003–2005)

According to a study published in "Nature Communications Earth and Environment" the Greenland ice sheet is possibly past the point of no return, meaning that even if the rise in temperature were to completely stop and even if the climate were to become a little colder, the melting would continue. This outcome is due to the movement of ice from the middle of Greenland to the coast, creating more contact between the ice and warmer coastal water and leading to more melting and calving. Another climate scientist says that after all the ice near the coast melts, the contact between the seawater and the ice will stop what can prevent further warming.[96][97]

In September 2020, satellite imagery showed that a big chunk of ice shattered into many small pieces from the last remaining ice shelf in Nioghalvfjerdsfjorden, Greenland.[98] This ice sheet is connected to the interior ice sheet, and could prove a hotspot for deglaciation in coming years.

Another unexpected effect of this melting relates to activities by the United States military in the area. Specifically, Camp Century, a nuclear powered base which has been producing nuclear waste over the years.[99] In 2016, a group of scientists evaluated the environmental impact and estimated that due to changing weather patterns over the next few decades, melt water could release the nuclear waste, 20,000 liters of chemical waste and 24 million liters of untreated sewage into the environment. However, so far neither US or Denmark has taken responsibility for the clean-up.[100]

### Changes in vegetation[edit]

Western Hemisphere Arctic Vegetation Index Trend Eastern Hemisphere Vegetation Index Trend

Climate change is expected to have a strong effect on the Arctic's flora, some of which is already being seen. These changes in vegetation are associated with the increases in landscape scale methane emissions,[101] as well as increases in CO2, Tº and the disruption of ecological cycles which affect patterns in nutrient cycling, humidity and other key ecological factors that help shape plant communities.[102]

A large source of information for how vegetation has adapted to climate change over the last years comes from satellite records, which help quantify shifts in vegetation in the Arctic region. For decades, NASA and NOAA satellites have continuously monitored vegetation from space. The Moderate Resolution Imaging Spectroradiometer (MODIS) and Advanced Very High-Resolution Radiometer (AVHRR) instruments, as well as others, measure the intensity of visible and near-infrared light reflecting off of plant leaves.[103] Scientists use this information to calculate the Normalized Difference Vegetation Index (NDVI),[104] an indicator of photosynthetic activity or "greenness" of the landscape, which is most often used. There also exist other indices, such as the Enhanced Vegetation Index (EVI) or Soil-Adjusted Vegetation Index (SAVI).[104]

These indices can be used as proxies for vegetation productivity, and their shifts over time can provide information on how vegetation changes over time. One of the two most used ways to define shifts in vegetation in the Arctic are the concepts of Arctic greening and Arctic browning. The former refers to a positive trend in the aforementioned greenness indices, indicating increases in plant cover or biomass whereas browning can be broadly understood as a negative trend, with decreases in those variables.[104]

Recent studies have allowed us to get an idea of how these two processes have progressed in recent years. It has been found that from 1985 to 2016, greening has occurred in 37.3% of all sites sampled in the tundra, whereas browning was observed only in 4.7% of them.[105] Certain variables influenced this distribution, as greening was mostly associated with sites with higher summer air temperature, soil temperature and soil moisture.[105] On the other hand, browning was found to be linked with colder sites that were experiencing cooling and drying.[105] Overall, this paints the picture of widespread greening occurring throughout significant portions of the arctic tundra, as a consequence of increases in plant productivity, height, biomass and shrub dominance in the area.

This expansion of vegetation in the Arctic is not equivalent across types of vegetation. One of the most dramatic changes arctic tundras are currently facing is the expansion of shrubs,[106] which, thanks to increases in air temperature and, to a lesser extent, precipitation have contributed to an Arctic-wide trend known as "shrubification", where shrub type plants are taking over areas previously dominated by moss and lichens. This change contributes to the consideration that the tundra biome is currently experiencing the most rapid change of any terrestrial biomes on the planet.[107]

The direct impact on mosses and lichens is unclear as there exist very few studies at species level, but climate change is more likely to cause increased fluctuation and more frequent extreme events.[108] The expansion of shrubs could affect permafrost dynamics, but the picture is quite unclear at the moment. In the winter, shrubs trap more snow, which insulates the permafrost from extreme cold spells, but in the summer they shade the ground from direct sunlight, how these two effects counter and balance each other is not yet well understood.[109] Warming is likely to cause changes in plant communities overall, contributing to the rapid changes tundra ecosystems are facing. While shrubs may increase in range and biomass, warming may also cause a decline in cushion plants such as moss campion, and since cushion plants act as facilitator species across trophic levels and fill important ecological niches in several environments, this could cause cascading effects in these ecosystems that could severely affect the way in which they function and are structured.[110]

The expansion of these shrubs can also have strong effects on other important ecological dynamics, such as the albedo effect.[111] These shrubs change the winter surface of the tundra from undisturbed, uniform snow to mixed surface with protruding branches disrupting the snow cover,[112] this type of snow cover has a lower albedo effect, with reductions of up to 55%, which contributes to a positive feedback loop on regional and global climate warming.[112] This reduction of the albedo effect means that more radiation is absorbed by plants, and thus, surface temperatures increase, which could disrupt current surface-atmosphere energy exchanges and affect thermal regimes of permafrost.[112] Carbon cycling is also being affected by these changes in vegetation, as parts of the tundra increase their shrub cover, they behave more like boreal forests in terms of carbon cycling.[113] This is speeding up the carbon cycle, as warmer temperatures lead to increased permafrost thawing and carbon release, but also carbon capturing from plants that have increased growth.[113] It is not certain whether this balance will go in one direction or the other, but studies have found that it is more likely that this will eventually lead to increased CO2 in the atmosphere.[113]

For a more graphic and geographically focused overview of the situation, maps above show the Arctic Vegetation Index Trend between July 1982 and December 2011 in the Arctic Circle. Shades of green depict areas where plant productivity and abundance increased; shades of brown show where photosynthetic activity declined, both according to the NDVI index. The maps show a ring of greening in the treeless tundra ecosystems of the circumpolar Arctic—the northernmost parts of Canada, Russia, and Scandinavia. Tall shrubs and trees started to grow in areas that were previously dominated by tundra grasses, as part of the previously mentioned "shrubification" of the tundra. Researchers concluded that plant growth had increased by 7% to 10% overall.

However, boreal forests, particularly those in North America, showed a different response to warming. Many boreal forests greened, but the trend was not as strong as it was for tundra of the circumpolar Arctic, mostly characterized by shrub expansion and increased growth.[114] In North America, some boreal forests actually experienced browning over the study period. Droughts, increased forest fire activity, animal behavior, industrial pollution, and a number of other factors may have contributed to browning.[104]

Another important change affecting flora in the arctic is the increase of wildfires in the Arctic Circle, which in 2020 broke its record of CO2 emissions, peaking at 244 megatonnes of carbon dioxide emitted.[115] This is due to the burning of peatlands, carbon-rich soils that originate from the accumulation of waterlogged plants which are mostly found at Arctic latitudes.[115] These peatlands are becoming more likely to burn as temperatures increase, but their own burning and releasing of CO2 contributes to their own likelihood of burning in a positive feedback loop.[115]

In terms of aquatic vegetation, reduction of sea ice has boosted the productivity of phytoplankton by about twenty percent over the past thirty years. However, the effect on marine ecosystems is unclear, since the larger types of phytoplankton, which are the preferred food source of most zooplankton, do not appear to have increased as much as the smaller types. So far, Arctic phytoplankton have not had a significant impact on the global carbon cycle.[116] In summer, the melt ponds on young and thin ice have allowed sunlight to penetrate the ice, in turn allowing ice algae to bloom in unexpected concentrations, although it is unknown just how long this phenomenon has been occurring, or what its effect on broader ecological cycles is.[117]

### Changes for animals[edit]

Further information: Effects of global warming on marine mammals

Projected change in polar bear habitat from 2001–2010 to 2041–2050

The northward shift of the subarctic climate zone is allowing animals that are adapted to that climate to move into the far north, where they are replacing species that are more adapted to a pure Arctic climate. Where the Arctic species are not being replaced outright, they are often interbreeding with their southern relations. Among slow-breeding vertebrate species, this usually has the effect of reducing the genetic diversity of the genus. Another concern is the spread of infectious diseases, such as brucellosis or phocine distemper virus, to previously untouched populations. This is a particular danger among marine mammals who were previously segregated by sea ice.[118]

On 3 April 2007, the National Wildlife Federation urged the United States Congress to place polar bears under the Endangered Species Act.[119] Four months later, the United States Geological Survey completed a year-long study[120] which concluded in part that the floating Arctic sea ice will continue its rapid shrinkage over the next 50 years, consequently wiping out much of the polar bear habitat. The bears would disappear from Alaska, but would continue to exist in the Canadian Arctic Archipelago and areas off the northern Greenland coast.[121] Secondary ecological effects are also resultant from the shrinkage of sea ice; for example, polar bears are denied their historic length of seal hunting season due to late formation and early thaw of pack ice.

Similarly, Arctic warming negatively affects the foraging and breeding ecology many other species of arctic marine mammals, such as walruses,[122] seals, foxes or reindeers.[123] In July 2019, 200 Svalbard reindeer were found starved to death apparently due to low precipitation related to climate change.[124]

In the short-term, climate warming may have neutral or positive effects on the nesting cycle of many Arctic-breeding shorebirds.[125]

## Permafrost thaw[edit]

Rapidly thawing Arctic permafrost and coastal erosion on the Beaufort Sea, Arctic Ocean, near Point Lonely, AK. Photo Taken in August 2013 Permafrost thaw ponds on Baffin Island

Permafrost is an important component of hydrological systems and ecosystems within the Arctic landscape.[126] In the Northern Hemisphere the terrestrial permafrost domain comprises around 18 million km2.[127] Within this permafrost region, the total soil organic carbon (SOC) stock is estimated to be 1,460-1,600 Pg (where 1 Pg = 1 billion tons), which constitutes double the amount of carbon currently contained in the atmosphere.[128][129]

This section is an excerpt from Permafrost carbon cycle § Carbon release from the permafrost.[edit]

Greater summer precipitation increases the depth of permafrost layer subject to thaw, in different Arctic permafrost environments.[130]

Carbon emissions from permafrost thaw contribute to the same warming which facilitates the thaw, making it a positive climate change feedback. The warming also intensifies Arctic water cycle, and the increased amounts of warmer rain are another factor which increases permafrost thaw depths.[130] The amount of carbon that will be released from warming conditions depends on depth of thaw, carbon content within the thawed soil, physical changes to the environment[131] and microbial and vegetation activity in the soil. Microbial respiration is the primary process through which old permafrost carbon is re-activated and enters the atmosphere. The rate of microbial decomposition within organic soils, including thawed permafrost, depends on environmental controls, such as soil temperature, moisture availability, nutrient availability, and oxygen availability.[132] In particular, sufficient concentrations of iron oxides in some permafrost soils can inhibit microbial respiration and prevent carbon mobilization: however, this protection only lasts until carbon is separated from the iron oxides by Fe-reducing bacteria, which is only a matter of time under the typical conditions.[133] Depending on the soil type, Iron(III) oxide can boost oxidation of methane to carbon dioxide in the soil, but it can also amplify methane production by acetotrophs: these soil processes are not yet fully understood.[134]

Altogether, the likelihood of the entire carbon pool mobilizing and entering the atmosphere is low despite the large volumes stored in the soil. Although temperatures will increase, this does not imply complete loss of permafrost and mobilization of the entire carbon pool. Much of the ground underlain by permafrost will remain frozen even if warming temperatures increase the thaw depth or increase thermokarsting and permafrost degradation.[135] Moreover, other elements such as iron and aluminum can adsorb some of the mobilized soil carbon before it reaches the atmosphere, and they are particularly prominent in the mineral sand layers which often overlay permafrost.[136] On the other hand, once the permafrost area thaws, it will not go back to being permafrost for centuries even if the temperature increase reversed, making it one of the best-known examples of tipping points in the climate system.

In 2011, preliminary computer analyses suggested that permafrost emissions could be equivalent to around 15% of anthropogenic emissions.[137]

A 2018 perspectives article discussing tipping points in the climate system activated around 2 °C (3.6 °F) of global warming suggested that at this threshold, permafrost thaw would add a further 0.09 °C (0.16 °F) to global temperatures by 2100, with a range of 0.04–0.16 °C (0.072–0.288 °F)[138] In 2021, another study estimated that in a future where zero emissions were reached following an emission of a further 1000 Pg C into the atmosphere (a scenario where temperatures ordinarily stay stable after the last emission, or start to decline slowly) permafrost carbon would add 0.06 °C (0.11 °F) (with a range of 0.02–0.14 °C (0.036–0.252 °F)) 50 years after the last anthropogenic emission, 0.09 °C (0.16 °F) (0.04–0.21 °C (0.072–0.378 °F)) 100 years later and 0.27 °C (0.49 °F) (0.12–0.49 °C (0.22–0.88 °F)) 500 years later.[139] However, neither study was able to take abrupt thaw into account.

In 2020, a study of the northern permafrost peatlands (a smaller subset of the entire permafrost area, covering 3.7 million km2 out of the estimated 18 million km2[140]) would amount to ~1% of anthropogenic radiative forcing by 2100, and that this proportion remains the same in all warming scenarios considered, from 1.5 °C (2.7 °F) to 6 °C (11 °F). It had further suggested that after 200 more years, those peatlands would have absorbed more carbon than what they had emitted into the atmosphere.[141]

The IPCC Sixth Assessment Report estimates that carbon dioxide and methane released from permafrost could amount to the equivalent of 14–175 billion tonnes of carbon dioxide per 1 °C (1.8 °F) of warming.[142]: 1237 For comparison, by 2019, annual anthropogenic emission of carbon dioxide alone stood around 40 billion tonnes.[142]: 1237

Nine probable scenarios of greenhouse gas emissions from permafrost thaw during the 21st century, which show a limited, moderate and intense CO2 and CH4 emission response to low, medium and high-emission Representative Concentration Pathways. The vertical bar uses emissions of selected large countries as a comparison: the right-hand side of the scale shows their cumulative emissions since the start of the Industrial Revolution, while the left-hand side shows each country's cumulative emissions for the rest of the 21st century if they remained unchanged from their 2019 levels.[143]

A 2021 assessment of the economic impact of climate tipping points estimated that permafrost carbon emissions would increase the social cost of carbon by about 8.4% [144] However, the methods of that assessment have attracted controversy: when researchers like Steve Keen and Timothy Lenton had accused it of underestimating the overall impact of tipping points and of higher levels of warming in general,[145] the authors have conceded some of their points.[146]

In 2021, a group of prominent permafrost researchers like Merritt Turetsky had presented their collective estimate of permafrost emissions, including the abrupt thaw processes, as part of an effort to advocate for a 50% reduction in anthropogenic emissions by 2030 as a necessary milestone to help reach net zero by 2050. Their figures for combined permafrost emissions by 2100 amounted to 150–200 billion tonnes of carbon dioxide equivalent under 1.5 °C (2.7 °F) of warming, 220–300 billion tonnes under 2 °C (3.6 °F) and 400–500 billion tonnes if the warming was allowed to exceed 4 °C (7.2 °F). They compared those figures to the extrapolated present-day emissions of Canada, the European Union and the United States or China, respectively. The 400–500 billion tonnes figure would also be equivalent to the today's remaining budget for staying within a 1.5 °C (2.7 °F) target.[147] One of the scientists involved in that effort, Susan M. Natali of Woods Hole Research Centre, had also led the publication of a complementary estimate in a PNAS paper that year, which suggested that when the amplification of permafrost emissions by abrupt thaw and wildfires is combined with the foreseeable range of near-future anthropogenic emissions, avoiding the exceedance (or "overshoot") of 1.5 °C (2.7 °F) warming is already implausible, and the efforts to attain it may have to rely on negative emissions to force the temperature back down.[148]

An updated 2022 assessment of climate tipping points concluded that abrupt permafrost thaw would add 50% to gradual thaw rates, and would add 14 billion tons of carbon dioxide equivalent emissions by 2100 and 35 billion tons by 2300 per every degree of warming. This would have a warming impact of 0.04 °C (0.072 °F) per every full degree of warming by 2100, and 0.11 °C (0.20 °F) per every full degree of warming by 2300. It also suggested that at between 3 °C (5.4 °F) and 6 °C (11 °F) degrees of warming (with the most likely figure around 4 °C (7.2 °F) degrees) a large-scale collapse of permafrost areas could become irreversible, adding between 175 and 350 billion tons of CO2 equivalent emissions, or 0.2–0.4 °C (0.36–0.72 °F) degrees, over about 50 years (with a range between 10 and 300 years).[149][150]

A major review published in the year 2022 concluded that if the goal of preventing 2 °C (3.6 °F) of warming was realized, then the average annual permafrost emissions throughout the 21st century would be equivalent to the year 2019 annual emissions of Russia. Under RCP4.5, a scenario considered close to the current trajectory and where the warming stays slightly below 3 °C (5.4 °F), annual permafrost emissions would be comparable to year 2019 emissions of Western Europe or the United States, while under the scenario of high global warming and worst-case permafrost feedback response, they would nearly match year 2019 emissions of China.[143]

This section is an excerpt from Permafrost § Construction on permafrost.[edit]

### Subsea permafrost[edit]

Subsea permafrost occurs beneath the seabed and exists in the continental shelves of the polar regions.[151] Thus, it can be defined as "the unglaciated continental shelf areas exposed during the Last Glacial Maximum (LGM, ~26 500 BP) that are currently inundated". Large stocks of organic matter (OM) and methane (CH4) are accumulated below and within the subsea permafrost deposits. This source of methane is different from methane clathrates, but contributes to the overall outcome and feedbacks in the Earth's climate system.[127]

Sea ice serves to stabilise methane deposits on and near the shoreline,[152] preventing the clathrate breaking down and venting into the water column and eventually reaching the atmosphere. Methane is released through bubbles from the subsea permafrost into the Ocean (a process called ebullition). During storms, methane levels in the water column drop dramatically, when wind-driven air-sea gas exchange accelerates the ebullition process into the atmosphere. This observed pathway suggests that methane from seabed permafrost will progress rather slowly, instead of abrupt changes. However, Arctic cyclones, fueled by global warming and further accumulation of greenhouse gases in the atmosphere could contribute to more release from this methane cache, which is really important for the Arctic.[153] An update to the mechanisms of this permafrost degradation was published in 2017.[154]

The size of today's subsea permafrost has been estimated at 2 million km2 (~1/5 of the terrestrial permafrost domain size), which constitutes a 30–50% reduction since the LGM. Containing around 560 GtC in OM and 45 GtC in CH4, with a current release of 18 and 38 MtC per year respectively, which is due to the warming and thawing that the subsea permafrost domain has been experiencing since after the LGM (~14000 years ago). In fact, because the subsea permafrost systems responds at millennial timescales to climate warming, the current carbon fluxes it is emitting to the water are in response to climatic changes occurring after the LGM. Therefore, human-driven climate change effects on subsea permafrost will only be seen hundreds or thousands of years from today. According to predictions under a business-as-usual emissions scenario RCP 8.5, by 2100, 43 GtC could be released from the subsea permafrost domain, and 190 GtC by the year 2300. Whereas for the low emissions scenario RCP 2.6, 30% less emissions are estimated. This constitutes a significant anthropogenic-driven acceleration of carbon release in the upcoming centuries.[127]

### Methane clathrate deposits[edit]

This section is an excerpt from Clathrate gun hypothesis.[edit]

Methane clathrate is released as gas into the surrounding water column or soils when ambient temperature increases The clathrate gun hypothesis is a proposed explanation for the periods of rapid warming during the Quaternary. The hypothesis is that changes in fluxes in upper intermediate waters in the ocean caused temperature fluctuations that alternately accumulated and occasionally released methane clathrate on upper continental slopes. This would have had an immediate impact on the global temperature, as methane is a much more powerful greenhouse gas than carbon dioxide. Despite its atmospheric lifetime of around 12 years, methane's global warming potential is 72 times greater than that of carbon dioxide over 20 years, and 25 times over 100 years (33 when accounting for aerosol interactions).[155] It is further proposed that these warming events caused the Bond Cycles and individual interstadial events, such as the Dansgaard–Oeschger interstadials.[156]

Most deposits of methane clathrate are in sediments too deep to respond rapidly,[157] and 2007 modelling by Archer suggests that the methane forcing derived from them should remain a minor component of the overall greenhouse effect.[158] Clathrate deposits destabilize from the deepest part of their stability zone, which is typically hundreds of metres below the seabed. A sustained increase in sea temperature will warm its way through the sediment eventually, and cause the shallowest, most marginal clathrate to start to break down; but it will typically take on the order of a thousand years or more for the temperature change to get that far into the seabed.[158] Further, subsequent research on midlatitude deposits in the Atlantic and Pacific Ocean found that any methane released from the seafloor, no matter the source, fails to reach the atmosphere once the depth exceeds 430 m (1,411 ft), while geological characteristics of the area make it impossible for hydrates to exist at depths shallower than 550 m (1,804 ft).[159][160]

Potential Methane release in the Eastern Siberian Arctic Shelf

However, some methane clathrates deposits in the Arctic are much shallower than the rest, which could make them far more vulnerable to warming. A trapped gas deposit on the continental slope off Canada in the Beaufort Sea, located in an area of small conical hills on the ocean floor is just 290 m (951 ft) below sea level and considered the shallowest known deposit of methane hydrate.[161] However, the East Siberian Arctic Shelf averages 45 meters in depth, and it is assumed that below the seafloor, sealed by sub-sea permafrost layers, hydrates deposits are located.[162][163] This would mean that when the warming potentially talik or pingo-like features within the shelf, they would also serve as gas migration pathways for the formerly frozen methane, and a lot of attention has been paid to that possibility.[164][165][166] Shakhova et al. (2008) estimate that not less than 1,400 gigatonnes of carbon is presently locked up as methane and methane hydrates under the Arctic submarine permafrost, and 5–10% of that area is subject to puncturing by open talik. Their paper initially included the line that the "release of up to 50 gigatonnes of predicted amount of hydrate storage [is] highly possible for abrupt release at any time". A release on this scale would increase the methane content of the planet's atmosphere by a factor of twelve,[167][168] equivalent in greenhouse effect to a doubling in the 2008 level of CO2.

This is what led to the original Clathrate gun hypothesis, and in 2008 the United States Department of Energy National Laboratory system[169] and the United States Geological Survey's Climate Change Science Program both identified potential clathrate destabilization in the Arctic as one of four most serious scenarios for abrupt climate change, which have been singled out for priority research. The USCCSP released a report in late December 2008 estimating the gravity of this risk.[170] A 2012 study of the effects for the original hypothesis, based on a coupled climate–carbon cycle model (GCM) assessed a 1000-fold (from <1 to 1000 ppmv) methane increase—within a single pulse, from methane hydrates (based on carbon amount estimates for the PETM, with ~2000 GtC), and concluded it would increase atmospheric temperatures by more than 6 °C within 80 years. Further, carbon stored in the land biosphere would decrease by less than 25%, suggesting a critical situation for ecosystems and farming, especially in the tropics.[171] Another 2012 assessment of the literature identifies methane hydrates on the Shelf of East Arctic Seas as a potential trigger.[172]

Methane releases in Laptev Sea are typically consumed within the sediment by methanotrophs. Areas with high sedimentation (top) subject their microbial communities to continual disturbance, and so they are the most likely to see active fluxes, whether with (right) or without active upward flow (left). Even so, the annual release may be limited to 1000 tonnes or less.[173]

Research carried out in 2008 in the Siberian Arctic showed methane releases on the annual scale of millions of tonnes, which was a substantial increase on the previous estimate of 0.5 millions of tonnes per year.[174] apparently through perforations in the seabed permafrost,[166] with concentrations in some regions reaching up to 100 times normal levels.[175][176] The excess methane has been detected in localized hotspots in the outfall of the Lena River and the border between the Laptev Sea and the East Siberian Sea. At the time, some of the melting was thought to be the result of geological heating, but more thawing was believed to be due to the greatly increased volumes of meltwater being discharged from the Siberian rivers flowing north.[177]

By 2013, the same team of researchers used multiple sonar observations to quantify the density of bubbles emanating from subsea permafrost into the ocean (a process called ebullition), and found that 100–630 mg methane per square meter is emitted daily along the East Siberian Arctic Shelf (ESAS), into the water column. They also found that during storms, when wind accelerates air-sea gas exchange, methane levels in the water column drop dramatically. Observations suggest that methane release from seabed permafrost will progress slowly, rather than abruptly. However, Arctic cyclones, fueled by global warming, and further accumulation of greenhouse gases in the atmosphere could contribute to more rapid methane release from this source. Altogether, their updated estimate had now amounted to 17 millions of tonnes per year.[178]

However, these findings were soon questioned, as this rate of annual release would mean that the ESAS alone would account for between 28% and 75% of the observed Arctic methane emissions, which contradicts many other studies. In January 2020, it was found that the rate at which methane enters the atmosphere after it had been released from the shelf deposits into the water column had been greatly overestimated, and observations of atmospheric methane fluxes taken from multiple ship cruises in the Arctic instead indicate that only around 3.02 million tonnes of methane are emitted annually from the ESAS.[179] A modelling study published in 2020 suggested that under the present-day conditions, annual methane release from the ESAS may be as low as 1000 tonnes, with 2.6 – 4.5 million tonnes representing the peak potential of turbulent emissions from the shelf.[173]

> The results of our study indicate that the immense seeping found in this area is a result of natural state of the system. Understanding how methane interacts with other important geological, chemical and biological processes in the Earth system is essential and should be the emphasis of our scientific community.[180]

Methane releases specifically attributed to hydrate dissociation in the Svalbard appear to be much lower than the leaks from other methane sources.[181]

Research by Klaus Wallmann et al. 2018 concluded that hydrate dissociation at Svalbard 8,000 years ago was due to isostatic rebound (continental uplift following deglaciation). As a result, the water depth got shallower with less hydrostatic pressure, without further warming. The study, also found that today's deposits at the site become unstable at a depth of ~ 400 meters, due to seasonal bottom water warming, and it remains unclear if this is due to natural variability or anthropogenic warming.[181] Moreover, another paper published in 2017 found that only 0.07% of the methane released from the gas hydrate dissociation at Svalbard appears to reach the atmosphere, and usually only when the wind speeds were low.[182] In 2020, a subsequent study confirmed that only a small fraction of methane from the Svalbard seeps reaches the atmosphere, and that the wind speed holds a greater influence on the rate of release than dissolved methane concentration on site.[183]

Finally, a paper published in 2017 indicated that the methane emissions from at least one seep field at Svalbard were more than compensated for by the enhanced carbon dioxide uptake due to the greatly increased phytoplankton activity in this nutrient-rich water. The daily amount of carbon dioxide absorbed by the phytoplankton was 1,900 greater than the amount of methane emitted, and the negative (i.e. indirectly cooling) radiative forcing from the CO2 uptake was up to 251 times greater than the warming from the methane release.[184]

In 2018, a perspective piece devoted to tipping points in the climate system suggested that the climate change contribution from methane hydrates would be "negligible" by the end of the century, but could amount to 0.4–0.5 °C (0.72–0.90 °F) on the millennial timescales.[185] In 2021, the IPCC Sixth Assessment Report no longer included methane hydrates in the list of potential tipping points, and says that "it is very unlikely that CH4 emissions from clathrates will substantially warm the climate system over the next few centuries."[186] The report had also linked terrestrial hydrate deposites to gas emission craters discovered in the Yamal Peninsula in Siberia, Russia beginning in July 2014,[187] but noted that since terrestrial gas hydrates predominantly form at a depth below 200 metres, a substantial response within the next few centuries can be ruled out.[186] Likewise, a 2022 assessment of tipping points described methane hydrates as a "threshold-free feedback" rather than a tipping point.[188][189]

## Effects on other parts of the world[edit]

### On ocean circulation[edit]

See also: Shutdown of thermohaline circulation and Ocean anoxic event

Although this is now thought unlikely in the near future, it has also been suggested that there could be a shutdown of thermohaline circulation, similar to that which is believed to have driven the Younger Dryas, an abrupt climate change event.[190] Even if a full shutdown is unlikely, a slowing down of this current and a weakening of its effects on climate has already been seen, with a 2015 study finding that the Atlantic meridional overturning circulation (AMOC) has weakened by 15% to 20% over the last 100 years.[7] This slowing could lead to cooling in the North Atlantic, although this could be mitigated by global warming, but it is not clear up to what extent.[191] Additional effects of this would be felt around the globe, with changes in tropical patterns, stronger storms in the North Atlantic and reduced European crop productivity among the potential repercussions.[191]

There is also potentially a possibility of a more general disruption of ocean circulation, which may lead to an ocean anoxic event; these are believed to be much more common in the distant past. It is unclear whether the appropriate pre-conditions for such an event exist today, but these ocean anoxic events are thought to have been mainly caused by nutrient run-off, which was driven by increased CO2 emissions in the distant past.[192] This draws an unsettling parallel with current climate change, but the amount of CO2 that's thought to have caused these events is far higher than the levels we're currently facing, so effects of this magnitude are considered unlikely on a short time scale.[193]

### On mid-latitude weather[edit]

As the Arctic continues to warm, the temperature gradient between it and the warmer parts of the globe will continue to diminish with every decade of global warming due to Arctic amplification. If this gradient has a strong influence on the jet stream, then it will eventually become weaker and more variable in its course, which would allow more cold air from the polar vortex to leak mid-latitudes and slow the progression of Rossby Waves, leading to more persistent and more extreme weather.

This section is an excerpt from Jet stream § Longer-term climatic changes.[edit]

The hypothesis above is closely associated with Jennifer Francis, who had first proposed it in a 2012 paper co-authored by Stephen J. Vavrus.[194] While some paleoclimate reconstructions have suggested that the polar vortex becomes more variable and causes more unstable weather during periods of warming back in 1997,[195] this was contradicted by climate modelling, with PMIP2 simulations finding in 2010 that the Arctic oscillation was much weaker and more negative during the Last Glacial Maximum, and suggesting that warmer periods have stronger positive phase AO, and thus less frequent leaks of the polar vortex air.[196] However, a 2012 review in the Journal of the Atmospheric Sciences noted that "there [has been] a significant change in the vortex mean state over the twenty-first century, resulting in a weaker, more disturbed vortex.",[197] which contradicted the modelling results but fit the Francis-Vavrus hypothesis. Additionally, a 2013 study noted that the then-current CMIP5 tended to strongly underestimate winter blocking trends,[198] and other 2012 research had suggested a connection between declining Arctic sea ice and heavy snowfall during midlatitude winters.[199]

In 2013, further research from Francis connected reductions in the Arctic sea ice to extreme summer weather in the northern mid-latitudes,[200] while other research from that year identified potential linkages between Arctic sea ice trends and more extreme rainfall in the European summer.[201] At the time, it was also suggested that this connection between Arctic amplification and jet stream patterns was involved in the formation of Hurricane Sandy[202] and played a role in the Early 2014 North American cold wave.[203][204] In 2015, Francis' next study concluded that highly amplified jet-stream patterns are occurring more frequently in the past two decades. Hence, continued heat-trapping emissions favour increased formation of extreme events caused by prolonged weather conditions.[205]

Studies published in 2017 and 2018 identified stalling patterns of Rossby waves in the northern hemisphere jet stream as the culprit behind other almost stationary extreme weather events, such as the 2018 European heatwave, the 2003 European heat wave, 2010 Russian heat wave or the 2010 Pakistan floods, and suggested that these patterns were all connected to Arctic amplification.[206][207] Further work from Francis and Vavrus that year suggested that amplified Arctic warming is observed as stronger in lower atmospheric areas because the expanding process of warmer air increases pressure levels which decreases poleward geopotential height gradients. As these gradients are the reason that cause west to east winds through the thermal wind relationship, declining speeds are usually found south of the areas with geopotential increases.[208] In 2017, Francis explained her findings to the Scientific American: "A lot more water vapor is being transported northward by big swings in the jet stream. That's important because water vapor is a greenhouse gas just like carbon dioxide and methane. It traps heat in the atmosphere. That vapor also condenses as droplets we know as clouds, which themselves trap more heat. The vapor is a big part of the amplification story—a big reason the Arctic is warming faster than anywhere else."[209]

In a 2017 study conducted by climatologist Dr. Judah Cohen and several of his research associates, Cohen wrote that "[the] shift in polar vortex states can account for most of the recent winter cooling trends over Eurasian midlatitudes".[210] A 2018 paper from Vavrus and others linked Arctic amplification to more persistent hot-dry extremes during the midlatitude summers, as well as the midlatitude winter continental cooling.[211] Another 2017 paper estimated that when the Arctic experiences anomalous warming, primary production in North America goes down by between 1% and 4% on average, with some states suffering up to 20% losses.[212] A 2021 study found that a stratospheric polar vortex disruption is linked with extreme cold winter weather across parts of Asia and North America, including the February 2021 North American cold wave.[213][214] Another 2021 study identified a connection between the Arctic sea ice loss and the increased size of wildfires in the Western United States.[215]

However, because the specific observations are considered short-term observations, there is considerable uncertainty in the conclusions. Climatology observations require several decades to definitively distinguish various forms of natural variability from climate trends.[216] This point was stressed by reviews in 2013[217] and in 2017.[218] A study in 2014 concluded that Arctic amplification significantly decreased cold-season temperature variability over the Northern Hemisphere in recent decades. Cold Arctic air intrudes into the warmer lower latitudes more rapidly today during autumn and winter, a trend projected to continue in the future except during summer, thus calling into question whether winters will bring more cold extremes.[219] A 2019 analysis of a data set collected from 35 182 weather stations worldwide, including 9116 whose records go beyond 50 years, found a sharp decrease in northern midlatitude cold waves since the 1980s.[220]

Moreover, a range of long-term observational data collected during 2010s and published in 2020s now suggests that the intensification of Arctic amplification since the early 2010s was not linked to significant changes on midlatitude atmospheric patterns.[221][222] State-of-the-art modelling research of PAMIP (Polar Amplification Model Intercomparison Project) improved upon the 2010 findings of PMIP2 - it did find that sea ice decline would weaken the jet stream and increase the probability of atmospheric blocking, but the connection was very minor, and typically insignificant next to interannual variability.[223][224] In 2022, a follow-up study found that while the PAMIP average had likely underestimated the weakening caused by sea ice decline by 1.2 to 3 times, even the corrected connection still amounts to only 10% of the jet stream's natural variability.[225]

## Impacts on people[edit]

### Territorial claims[edit]

Main article: Territorial claims in the Arctic

Growing evidence that global warming is shrinking polar ice has added to the urgency of several nations' Arctic territorial claims in hopes of establishing resource development and new shipping lanes, in addition to protecting sovereign rights.[226]

As ice sea coverage decreases more and more, year on year, Arctic countries (Russia, Canada, Finland, Iceland, Norway, Sweden, the United States and Denmark representing Greenland) are making moves on the geopolitical stage to ensure access to potential new shipping lanes, oil and gas reserves, leading to overlapping claims across the region.[227] However, there is only one single land border dispute in the Arctic, with all others relating to the sea, that is Hans Island.[228] This small uninhabited island lies in the Nares strait, between Canada's Ellesmere Island and the northern coast of Greenland. Its status comes from its geographical position, right between the equidistant boundaries determined in a 1973 treaty between Canada and Denmark.[228] Even though both countries have acknowledged the possibility of splitting the island, no agreement on the island has been reached, with both nations still claiming it for themselves.[228]

There is more activity in terms of maritime boundaries between countries, where overlapping claims for internal waters, territorial seas and particularly Exclusive Economic Zones (EEZs) can cause frictions between nations. Currently, official maritime borders have an unclaimed triangle of international waters lying between them, that is at the centerpoint of international disputes.[227]

This unclaimed land can be obtainable by submitting a claim to the United Nations Convention on the Law of the Sea, these claims can be based on geological evidence that continental shelves extend beyond their current maritime borders and into international waters.[227]

Some overlapping claims are still pending resolution by international bodies, such as a large portion containing the north pole that is both claimed by Denmark and Russia, with some parts of it also contested by Canada.[227] Another example is that of the Northwest Passage, globally recognized as international waters, but technically in Canadian waters.[227] This has led to Canada wanting to limit the number of ships that can go through for environmental reasons but the United States disputes that they have the authority to do so, favouring unlimited passage of vessels.[227]

### Impacts on indigenous peoples[edit]

As climate change speeds up, it is having more and more of a direct impact on societies around the world. This is particularly true of people that live in the Arctic, where increases in temperature are occurring at faster rates than at other latitudes in the world, and where traditional ways of living, deeply connected with the natural arctic environment are at particular risk of environmental disruption caused by these changes.[229]

The warming of the atmosphere and ecological changes that come alongside it presents challenges to local communities such as the Inuit. Hunting, which is a major way of survival for some small communities, will be changed with increasing temperatures.[230] The reduction of sea ice will cause certain species populations to decline or even become extinct.[229] Inuit communities are deeply reliant on seal hunting, which is dependent on sea ice flats, where seals are hunted.[231]

Unsuspected changes in river and snow conditions will cause herds of animals, including reindeer, to change migration patterns, calving grounds, and forage availability.[229] In good years, some communities are fully employed by the commercial harvest of certain animals.[230] The harvest of different animals fluctuates each year and with the rise of temperatures it is likely to continue changing and creating issues for Inuit hunters, as unpredictability and disruption of ecological cycles further complicate life in these communities, which already face significant problems, such as Inuit communities being the poorest and most unemployed of North America.[231]

Other forms of transportation in the Arctic have seen negative impacts from the current warming, with some transportation routes and pipelines on land being disrupted by the melting of ice.[229] Many Arctic communities rely on frozen roadways to transport supplies and travel from area to area.[229] The changing landscape and unpredictability of weather is creating new challenges in the Arctic.[232] Researchers have documented historical and current trails created by the Inuit in the Pan Inuit Trails Atlas, finding that the change in sea ice formation and breakup has resulted in changes to the routes of trails created by the Inuit.[233]

### Navigation[edit]

The Transpolar Sea Route is a future Arctic shipping lane running from the Atlantic Ocean to the Pacific Ocean across the center of the Arctic Ocean. The route is also sometimes called Trans-Arctic Route. In contrast to the Northeast Passage (including the Northern Sea Route) and the North-West Passage it largely avoids the territorial waters of Arctic states and lies in international high seas.[234]

Governments and private industry have shown a growing interest in the Arctic.[235] Major new shipping lanes are opening up: the northern sea route had 34 passages in 2011 while the Northwest Passage had 22 traverses, more than any time in history.[236] Shipping companies may benefit from the shortened distance of these northern routes. Access to natural resources will increase, including valuable minerals and offshore oil and gas.[229] Finding and controlling these resources will be difficult with the continually moving ice.[229] Tourism may also increase as less sea ice will improve safety and accessibility to the Arctic.[229]

The melting of Arctic ice caps is likely to increase traffic in and the commercial viability of the Northern Sea Route. One study, for instance, projects, "remarkable shifts in trade flows between Asia and Europe, diversion of trade within Europe, heavy shipping traffic in the Arctic and a substantial drop in Suez traffic. Projected shifts in trade also imply substantial pressure on an already threatened Arctic ecosystem."[237]

## Adaptation[edit]

### Research[edit]

#### National[edit]

Individual countries within the Arctic zone, Canada, Denmark (Greenland), Finland, Iceland, Norway, Russia, Sweden, and the United States (Alaska) conduct independent research through a variety of organizations and agencies, public and private, such as Russia's Arctic and Antarctic Research Institute. Countries who do not have Arctic claims, but are close neighbors, conduct Arctic research as well, such as the Chinese Arctic and Antarctic Administration (CAA). The United States's National Oceanic and Atmospheric Administration (NOAA) produces an Arctic Report Card annually, containing peer-reviewed information on recent observations of environmental conditions in the Arctic relative to historical records.[14][15]

#### International[edit]

International cooperative research between nations has become increasingly important:

* Arctic climate change is summarized by the Intergovernmental Panel on Climate Change (IPCC) in its series of Assessment Reports and the Arctic Climate Impact Assessment.
* European Space Agency (ESA) launched CryoSat-2 on 8 April 2010. It provides satellite data on Arctic ice cover change rates.[238]
* International Arctic Buoy Program: deploys and maintains buoys that provide real-time position, pressure, temperature, and interpolated ice velocity data
* International Arctic Research Center: Main participants are the United States and Japan.
* International Arctic Science Committee: non-governmental organization (NGO) with diverse membership, including 23 countries from 3 continents.
* 'Role of the Arctic Region', in conjunction with the International Polar Year, was the focus of the second international conference on Global Change Research, held in Nynäshamn, Sweden, October 2007.[239]
* SEARCH (Study of Environmental Arctic Change): A research framework originally promoted by several US agencies; an international extension is ISAC (the International Study of Arctic Change[240]).

## See also[edit]

* Climate change portal
* Ecology portal
* Environment portal

* Arctic cooperation and politics
* Arctic haze
* Arctic sea ice ecology and history
* Atlantification of the Arctic
* Atmospheric Brown Cloud
* Climate of the Arctic
* Climate and vegetation interactions in the Arctic
* Northern Sea Route
* Climate change in Antarctica
* Ozone depletion and climate change
* Save the Arctic

## References[edit]

1. ^ Kessler, Louise (May 2017). "Estimating the Economic Impact of the Permafrost Carbon Feedback". Climate Change Economics. 08 (2): 1750008. doi:10.1142/s2010007817500087. ISSN 2010-0078.
2. ^ a b Arvelo, Juan (2011). An Under-Ice Arctic Geophysical Exploration Sonar System Concept To Resolve International Territorial Claims. Proceedings of Meetings on Acoustics. Vol. 12\. Acoustical Society of America. p. 070002\. doi:10.1121/1.3626896.
3. ^ Intergovernmental Panel on Climate Change (2007). "3.3.3 Especially affected systems, sectors and regions". Synthesis report (PDF). Climate Change 2007: Synthesis Report. A Contribution of Working Groups I, II, and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). Geneva, Switzerland: IPCC. Retrieved 15 September 2011.[permanent dead link]
4. ^ Anisimov, O.A. (2007). "15.3.2 Projected atmospheric changes". In Parry, M.L.; et al. (eds.). Chapter 15: Polar Regions (Arctic and Antarctic). Climate change 2007: impacts, adaptation and vulnerability: contribution of Working Group II to the fourth assessment report of the Intergovernmental Panel on Climate Change (IPCC). Cambridge University Press (CUP): Cambridge, UK: Print version: CUP. This version: IPCC website. ISBN 978-0-521-88010-7. Retrieved 15 September 2011.
5. ^ a b c Chylek, Petr; Folland, Chris; Klett, James D.; Wang, Muyin; Hengartner, Nick; Lesins, Glen; Dubey, Manvendra K. (16 July 2022). "Annual Mean Arctic Amplification 1970–2020: Observed and Simulated by CMIP6 Climate Models". Geophysical Research Letters. 49 (13). Bibcode:2022GeoRL..4999371C. doi:10.1029/2022GL099371. ISSN 0094-8276. S2CID 250097858. via Wikipedia Library and EBSCOhost
6. ^ a b c "Arctic temperatures are increasing four times faster than global warming". Los Alamos National Laboratory. Retrieved 18 July 2022.
7. ^ a b "Atlantic Ocean circulation shows "exceptional" slowdown". Physics Today. 2015. doi:10.1063/pt.5.028751. ISSN 1945-0699.
8. ^ Francis, Jennifer A.; Vavrus, Stephen J. (17 March 2012). "Evidence linking Arctic amplification to extreme weather in mid-latitudes". Geophysical Research Letters. 39 (6): n/a. Bibcode:2012GeoRL..39.6801F. doi:10.1029/2012gl051000. ISSN 0094-8276. S2CID 15383119.
9. ^ a b AMAP Arctic Climate Change Update 2021: Key Trends and Impacts. Arctic Monitoring and Assessment Programme (AMAP) (Report). Tromsø, Norway. 2021. pp. viii + 148. ISBN 978-82-7971-201-5.
10. ^ Arias, Paola A.; Bellouin, Nicolas; Coppola, Erika; Jones, Richard G.; et al. (2021). "Technical Summary" (PDF). IPCC AR6 WG1. p. 76.
11. ^ Rantanen, Mika; Karpechko, Alexey Yu; Lipponen, Antti; Nordling, Kalle; Hyvärinen, Otto; Ruosteenoja, Kimmo; Vihma, Timo; Laaksonen, Ari (11 August 2022). "The Arctic has warmed nearly four times faster than the globe since 1979". Communications Earth & Environment. 3 (1): 168. Bibcode:2022ComEE...3..168R. doi:10.1038/s43247-022-00498-3. ISSN 2662-4435. S2CID 251498876.
12. ^ a b Rapid and pronounced warming continues to drive the evolution of the Arctic environment (Report). Arctic Report Card: Update for 2021. NOAA.
13. ^ a b Druckenmiller, Matthew; Thoman, Rick; Moon, Twila (14 December 2021). "2021 Arctic Report Card reveals a (human) story of cascading disruptions, extreme events and global connections". The Conversation. Retrieved 30 January 2022.
14. ^ a b Freedman, Andrew (12 December 2017). "Arctic warming, ice melt 'unprecedented' in at least the past 1,500 years". Mashable. Retrieved 13 December 2017.
15. ^ a b "Arctic Report Card: Update for 2017; Arctic shows no sign of returning to reliably frozen region of recent past decades". NOAA. Retrieved 13 December 2017.
16. ^ Impacts of a Warming Arctic: Arctic Climate Impact Assessment. Arctic Climate Impact Assessment (ACIA) (Report). Overview report. Cambridge University Press. 15 October 2004. p. 140\. ISBN 0-521-61778-2.
17. ^ a b c Spreading like Wildfire – The Rising Threat of Extraordinary Landscape Fires. United Nations Environment Programme (UNEP) (Report). A UNEP Rapid Response Assessment. Nairobi, Kenya. 2022. p. 122.
18. ^ a b McGrath, Matt (19 March 2022). "Climate change: Wildfire smoke linked to Arctic melting". BBC. Retrieved 20 March 2022.
19. ^ Ciavarella, A.; Cotterill, D.; Stott, P. (2021). "Prolonged Siberian heat of 2020 almost impossible without human influence". Climatic Change. 166 (9): 9. Bibcode:2021ClCh..166....9C. doi:10.1007/s10584-021-03052-w. PMC 8550097. PMID 34720262. S2CID 233875870.
20. ^ "Polar Regions (Arctic and Antarctic) — IPCC". Retrieved 18 May 2021.[permanent dead link]
21. ^ Przybylak, Rajmund (2007). "Recent air-temperature changes in the Arctic". Annals of Glaciology. 46 (1): 316–324. Bibcode:2007AnGla..46..316P. doi:10.3189/172756407782871666. S2CID 129155170.
22. ^ "Surface Air Temperature". Arctic Program. October 2020. Retrieved 18 May 2021.
23. ^ Yu, Yining; Xiao, Wanxin; Zhang, Zhilun; Cheng, Xiao; Hui, Fengming; Zhao, Jiechen (17 July 2021). "Evaluation of 2-m Air Temperature and Surface Temperature from ERA5 and ERA-I Using Buoy Observations in the Arctic during 2010–2020". Remote Sensing. 13 (Polar Sea Ice: Detection, Monitoring and Modeling): 2813. Bibcode:2021RemS...13.2813Y. doi:10.3390/rs13142813.
24. ^ Arctic Climate Impact Assessment (2004): Arctic Climate Impact Assessment. Cambridge University Press, ISBN 0-521-61778-2, siehe online Archived 28 June 2013 at the Wayback Machine
25. ^ Quinn, P.K., T. S. Bates, E. Baum et al. (2007): Short-lived pollutants in the Arctic: their climate impact and possible mitigation strategies, in: Atmospheric Chemistry and Physics, Vol. 7, S. 15669–15692, siehe online
26. ^ Arctic Temperatures Highest in at Least 44,000 Years, Livescience, 24 October 2013
27. ^ Miller, G. H.; Lehman, S. J.; Refsnider, K. A.; Southon, J. R.; Zhong, Y. (2013). "Unprecedented recent summer warmth in Arctic Canada". Geophysical Research Letters. 40 (21): 5745–5751. Bibcode:2013GeoRL..40.5745M. doi:10.1002/2013GL057188. S2CID 128849141.
28. ^ Rosane, Olivia (22 June 2020). "A Siberian Town Just Hit 100 F Degrees". Ecowatch. Retrieved 23 June 2020.
29. ^ King, Simon; Rowlatt, Justin (22 June 2020). "Arctic Circle sees 'highest-ever' recorded temperatures". BBC. Retrieved 23 June 2020.
30. ^ Rowlatt, Justin (15 July 2020). "Climate change: Siberian heatwave 'clear evidence' of warming". BBC. Retrieved 17 July 2020.
31. ^ Kuebler, Martin; Schauenberg, Tim (13 July 2020). "Record heat wave in Siberia: What happens when climate change goes extreme?". Deutch Welle. Retrieved 28 July 2020.
32. ^ Serreze, Mark. "5 ways the extreme Arctic heat wave follows a disturbing pattern". Phys.org. Retrieved 28 July 2020.
33. ^ Chao-Fong, Léonie (7 January 2021). "'Drastic' rise in high Arctic lightning has scientists worried". The Guardian. Retrieved 30 January 2022.
34. ^ Deser, Clara; Walsh, John E.; Timlin, Michael S. (1 February 2000). "Arctic Sea Ice Variability in the Context of Recent Atmospheric Circulation Trends". J. Climate. 13 (3): 617–633. Bibcode:2000JCli...13..617D. CiteSeerX 10.1.1.384.2863. doi:10.1175/1520-0442(2000)013<0617:ASIVIT>2.0.CO;2.
35. ^ Rantanen, Mika; Karpechko, Alexey Yu; Lipponen, Antti; Nordling, Kalle; Hyvärinen, Otto; Ruosteenoja, Kimmo; Vihma, Timo; Laaksonen, Ari (11 August 2022). "The Arctic has warmed nearly four times faster than the globe since 1979". Communications Earth & Environment. 3 (1): 168. Bibcode:2022ComEE...3..168R. doi:10.1038/s43247-022-00498-3. hdl:11250/3115996. ISSN 2662-4435. S2CID 251498876.
36. ^ Dai, Aiguo; Luo, Dehai; Song, Mirong; Liu, Jiping (10 January 2019). "Arctic amplification is caused by sea-ice loss under increasing CO2". Nature Communications. 10 (1): 121. Bibcode:2019NatCo..10..121D. doi:10.1038/s41467-018-07954-9. PMC 6328634. PMID 30631051.2&rft.volume=10&rft.issue=1&rft.pages=121&rft.date=2019-01-10&rft_id=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6328634#id-name=PMC&rft_id=info:pmid/30631051&rft_id=info:doi/10.1038/s41467-018-07954-9&rft_id=info:bibcode/2019NatCo..10..121D&rft.aulast=Dai&rft.aufirst=Aiguo&rft.au=Luo,+Dehai&rft.au=Song,+Mirong&rft.au=Liu,+Jiping&rft_id=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6328634&rfr_id=info:sid/en.wikipedia.org:Climate+change+in+the+Arctic" class="Z3988">
37. ^ Singh, Hansi A.; Polvani, Lorenzo M. (10 January 2020). "Low Antarctic continental climate sensitivity due to high ice sheet orography". npj Climate and Atmospheric Science. 3. doi:10.1038/s41612-020-00143-w. S2CID 222179485.
38. ^ Steig, Eric; Schneider, David; Rutherford, Scott; Mann, Michael E.; Comiso, Josefino; Shindell, Drew (1 January 2009). "Warming of the Antarctic ice-sheet surface since the 1957 International Geophysical Year". Arts & Sciences Faculty Publications.
39. ^ Xin, Meijiao; Li, Xichen; Stammerjohn, Sharon E; Cai, Wenju; Zhu, Jiang; Turner, John; Clem, Kyle R; Song, Chentao; Wang, Wenzhu; Hou, Yurong (17 May 2023). "A broadscale shift in antarctic temperature trends". Climate Dynamics. 61 (9–10): 4623–4641. Bibcode:2023ClDy...61.4623X. doi:10.1007/s00382-023-06825-4. S2CID 258777741.
40. ^ Auger, Matthis; Morrow, Rosemary; Kestenare, Elodie; Nordling, Kalle; Sallée, Jean-Baptiste; Cowley, Rebecca (21 January 2021). "Southern Ocean in-situ temperature trends over 25 years emerge from interannual variability". Nature Communications. 10 (1): 514. Bibcode:2021NatCo..12..514A. doi:10.1038/s41467-020-20781-1. PMC 7819991. PMID 33479205.
41. ^ Pistone, Kristina; Eisenman, Ian; Ramanathan, Veerabhadran (2019). "Radiative Heating of an Ice-Free Arctic Ocean". Geophysical Research Letters. 46 (13): 7474–7480. Bibcode:2019GeoRL..46.7474P. doi:10.1029/2019GL082914. ISSN 1944-8007. S2CID 197572148.
42. ^ Arias, Paola A.; Bellouin, Nicolas; Coppola, Erika; Jones, Richard G.; et al. (2021). "Technical Summary" (PDF). IPCC AR6 WG1. p. 76.
43. ^ Riihelä, Aku; Bright, Ryan M.; Anttila, Kati (28 October 2021). "Recent strengthening of snow and ice albedo feedback driven by Antarctic sea-ice loss". Nature Geoscience. 14: 832–836. doi:10.1038/s41561-021-00841-x. hdl:11250/2830682.
44. ^ "Thermodynamics: Albedo". NSIDC.
45. ^ "Polar Vortex: How the Jet Stream and Climate Change Bring on Cold Snaps". InsideClimate News. 2 February 2018. Retrieved 24 November 2018.
46. ^ a b "Arctic warming three times faster than the planet, report warns". Phys.org. 20 May 2021. Retrieved 6 October 2022.
47. ^ Rantanen, Mika; Karpechko, Alexey Yu; Lipponen, Antti; Nordling, Kalle; Hyvärinen, Otto; Ruosteenoja, Kimmo; Vihma, Timo; Laaksonen, Ari (11 August 2022). "The Arctic has warmed nearly four times faster than the globe since 1979". Communications Earth & Environment. 3 (1): 1–10. doi:10.1038/s43247-022-00498-3. hdl:11250/3115996. ISSN 2662-4435. S2CID 251498876.
48. ^ "The Arctic is warming four times faster than the rest of the world". 14 December 2021. Retrieved 6 October 2022.
49. ^ Isaksen, Ketil; Nordli, Øyvind; et al. (15 June 2022). "Exceptional warming over the Barents area". Scientific Reports. 12 (1): 9371. doi:10.1038/s41598-022-13568-5. PMC 9200822. PMID 35705593. S2CID 249710630.
50. ^ Damian Carrington (15 June 2022). "New data reveals extraordinary global heating in the Arctic". The Guardian. Retrieved 7 October 2022.
51. ^ Armstrong McKay, David; Abrams, Jesse; Winkelmann, Ricarda; Sakschewski, Boris; Loriani, Sina; Fetzer, Ingo; Cornell, Sarah; Rockström, Johan; Staal, Arie; Lenton, Timothy (9 September 2022). "Exceeding 1.5°C global warming could trigger multiple climate tipping points". Science. 377 (6611): eabn7950. doi:10.1126/science.abn7950. hdl:10871/131584. ISSN 0036-8075. PMID 36074831. S2CID 252161375.
52. ^ Armstrong McKay, David (9 September 2022). "Exceeding 1.5°C global warming could trigger multiple climate tipping points – paper explainer". climatetippingpoints.info. Retrieved 2 October 2022.
53. ^ a b Chylek, Petr; Folland, Chris; Klett, James D.; Wang, Muyin; Hengartner, Nick; Lesins, Glen; Dubey, Manvendra K. (25 June 2022). "Annual Mean Arctic Amplification 1970–2020: Observed and Simulated by CMIP6 Climate Models". Geophysical Research Letters. 49 (13). doi:10.1029/2022GL099371. S2CID 250097858.
54. ^ Acosta Navarro, J.C.; Varma, V.; Riipinen, I.; Seland, Ø.; Kirkevåg, A.; Struthers, H.; Iversen, T.; Hansson, H.-C.; Ekman, A. M. L. (14 March 2016). "Amplification of Arctic warming by past air pollution reductions in Europe". Nature Geoscience. 9 (4): 277–281. Bibcode:2016NatGe...9..277A. doi:10.1038/ngeo2673.
55. ^ Harvey, C. (14 March 2016). "How cleaner air could actually make global warming worse". Washington Post.
56. ^ Chylek, Petr; Folland, Chris K.; Lesins, Glen; Dubey, Manvendra K.; Wang, Muyin (16 July 2009). "Arctic air temperature change amplification and the Atlantic Multidecadal Oscillation". Geophysical Research Letters. 36 (14): L14801. Bibcode:2009GeoRL..3614801C. CiteSeerX 10.1.1.178.6926. doi:10.1029/2009GL038777. S2CID 14013240.
57. ^ a b Qi, Ling; Wang, Shuxiao (November 2019). "Sources of black carbon in the atmosphere and in snow in the Arctic". Science of the Total Environment. 691: 442–454. Bibcode:2019ScTEn.691..442Q. doi:10.1016/j.scitotenv.2019.07.073. ISSN 0048-9697. PMID 31323589. S2CID 198135020.
58. ^ Stohl, A.; Klimont, Z.; Eckhardt, S.; Kupiainen, K.; Chevchenko, V.P.; Kopeikin, V.M.; Novigatsky, A.N. (2013), "Black carbon in the Arctic: the underestimated role of gas flaring and residential combustion emissions", Atmos. Chem. Phys., 13 (17): 8833–8855, Bibcode:2013ACP....13.8833S, doi:10.5194/acp-13-8833-2013
59. ^ Stanley, Michael (10 December 2018). "Gas flaring: An industry practice faces increasing global attention" (PDF). World Bank. Archived from the original (PDF) on 15 February 2019. Retrieved 20 January 2020.
60. ^ Zhu, Chunmao; Kanaya, Yugo; Takigawa, Masayuki; Ikeda, Kohei; Tanimoto, Hiroshi; Taketani, Fumikazu; Miyakawa, Takuma; Kobayashi, Hideki; Pisso, Ignacio (24 September 2019). "Flexpart v10.1 simulation of source contributions to Arctic black carbon". Atmospheric Chemistry and Physics. doi:10.5194/acp-2019-590. S2CID 204117555.
61. ^ "The Race to Understand Black Carbon's Climate Impact". ClimateCentral. 2017. Archived from the original on 22 November 2017. Retrieved 21 May 2017.
62. ^ Zhang, Qiang; Wan, Zheng; Hemmings, Bill; Abbasov, Faig (December 2019). "Reducing black carbon emissions from Arctic shipping: Solutions and policy implications". Journal of Cleaner Production. 241: 118261. doi:10.1016/j.jclepro.2019.118261. ISSN 0959-6526. S2CID 203303955.
63. ^ Huang, Yiyi; Dong, Xiquan; Bailey, David A.; Holland, Marika M.; Xi, Baike; DuVivier, Alice K.; Kay, Jennifer E.; Landrum, Laura L.; Deng, Yi (19 June 2019). "Thicker Clouds and Accelerated Arctic Sea Ice Decline: The Atmosphere-Sea Ice Interactions in Spring". Geophysical Research Letters. 46 (12): 6980–6989. Bibcode:2019GeoRL..46.6980H. doi:10.1029/2019gl082791. hdl:10150/634665. ISSN 0094-8276. S2CID 189968828.
64. ^ Senftleben, Daniel; Lauer, Axel; Karpechko, Alexey (15 February 2020). "Constraining Uncertainties in CMIP5 Projections of September Arctic Sea Ice Extent with Observations". Journal of Climate. 33 (4): 1487–1503. Bibcode:2020JCli...33.1487S. doi:10.1175/jcli-d-19-0075.1. ISSN 0894-8755. S2CID 210273007.
65. ^ Yadav, Juhi; Kumar, Avinash; Mohan, Rahul (21 May 2020). "Dramatic decline of Arctic sea ice linked to global warming". Natural Hazards. 103 (2): 2617–2621. Bibcode:2020NatHa.103.2617Y. doi:10.1007/s11069-020-04064-y. ISSN 0921-030X. S2CID 218762126.
66. ^ "Ice in the Arctic is melting even faster than scientists expected, study finds". NPR.org. Retrieved 10 July 2022.
67. ^ Fisher, David; Zheng, James; Burgess, David; Zdanowicz, Christian; Kinnard, Christophe; Sharp, Martin; Bourgeois, Jocelyne (March 2012). "Recent melt rates of Canadian arctic ice caps are the highest in four millennia". Global and Planetary Change. 84: 3–7. Bibcode:2012GPC....84....3F. doi:10.1016/j.gloplacha.2011.06.005.
68. ^ J. C. Stroeve; T. Markus; L. Boisvert; J. Miller; A. Barrett (2014). "Changes in Arctic melt season and implications for sea ice loss". Geophysical Research Letters. 41 (4): 1216–1225. Bibcode:2014GeoRL..41.1216S. doi:10.1002/2013GL058951. S2CID 131673760.
69. ^ IPCC AR6 WG1 Ch9 2021, p. 9-6, line 19
70. ^ "Arctic summer sea ice second lowest on record: US researchers". phys.org. 21 September 2020.
71. ^ Slater, T. S.; Lawrence, I. S.; Otosaka, I. N.; Shepherd, A.; Gourmelen, N.; Jakob, L.; Tepes, P.; Gilbert, L.; Nienow, P. (25 January 2021). "Review article: Earth's ice imbalance". The Cryosphere. 15 (1): 233–246. Bibcode:2021TCry...15..233S. doi:10.5194/tc-15-233-2021. hdl:20.500.11820/df343a4d-6b66-4eae-ac3f-f5a35bdeef04.
72. ^ Lawrence, D. M.; Slater, A. (2005). "A projection of severe near-surface permafrost degradation during the 21st century". Geophysical Research Letters. 32 (24): L24401. Bibcode:2005GeoRL..3224401L. doi:10.1029/2005GL025080. S2CID 128425266.
73. ^ a b Stroeve, J.; Holland, M. M.; Meier, W.; Scambos, T.; Serreze, M. (2007). "Arctic sea ice decline: Faster than forecast". Geophysical Research Letters. 34 (9): L09501. Bibcode:2007GeoRL..34.9501S. doi:10.1029/2007GL029703.
74. ^ Comiso, Josefino C.; Parkinson, Claire L.; Gersten, Robert; Stock, Larry (2008). "Accelerated decline in Arctic sea ice cover". Geophysical Research Letters. 35 (1): L01703. Bibcode:2008GeoRL..35.1703C. doi:10.1029/2007GL031972. S2CID 129445545.
75. ^ Comiso, Josefino C.; Parkinson, Claire L.; Gersten, Robert; Stock, Larry (3 January 2008). "Accelerated decline in the Arctic sea ice cover". Geophysical Research Letters. 35 (1): L01703. Bibcode:2008GeoRL..35.1703C. doi:10.1029/2007gl031972. ISSN 0094-8276. S2CID 129445545.
76. ^ "Record Arctic sea ice minimum confirmed by NSIDC". Archived from the original on 29 July 2013.
77. ^ Petty, Alek A.; Stroeve, Julienne C.; Holland, Paul R.; Boisvert, Linette N.; Bliss, Angela C.; Kimura, Noriaki; Meier, Walter N. (6 February 2018). "The Arctic sea ice cover of 2016: a year of record-low highs and higher-than-expected lows". The Cryosphere. 12 (2): 433–452. Bibcode:2018TCry...12..433P. doi:10.5194/tc-12-433-2018. ISSN 1994-0424.
78. ^ a b Yadav, Juhi; Kumar, Avinash; Mohan, Rahul (21 May 2020). "Dramatic decline of Arctic sea ice linked to global warming". Natural Hazards. 103 (2): 2617–2621. doi:10.1007/s11069-020-04064-y. ISSN 0921-030X. S2CID 218762126.
79. ^ "Arctic summer sea ice loss may not 'tip' over the edge". environmentalresearchweb. 30 January 2009. Archived from the original on 2 February 2009. Retrieved 26 July 2010.
80. ^ a b Senftleben, Daniel; Lauer, Axel; Karpechko, Alexey (15 February 2020). "Constraining Uncertainties in CMIP5 Projections of September Arctic Sea Ice Extent with Observations". Journal of Climate. 33 (4): 1487–1503. Bibcode:2020JCli...33.1487S. doi:10.1175/jcli-d-19-0075.1. ISSN 0894-8755. S2CID 210273007.
81. ^ a b "Arctic sea ice extent remains low; 2009 sees third-lowest mark". NSIDC. 6 October 2009. Archived from the original on 26 December 2012. Retrieved 26 July 2010.
82. ^ Black, Richard (18 May 2007). "Earth – melting in the heat?". BBC News. Retrieved 3 January 2008.
83. ^ a b Meehl, G.A.; et al. (2007). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Chapter 10 (PDF). New York: Cambridge University Press.
84. ^ a b Gregory JM; Huybrechts P; Raper SC (April 2004). "Climatology: threatened loss of the Greenland ice-sheet" (PDF). Nature. 428 (6983): 616. Bibcode:2004Natur.428..616G. doi:10.1038/428616a. PMID 15071587. S2CID 4421590. Archived from the original (PDF) on 9 August 2017. Retrieved 5 April 2008. "The Greenland ice-sheet would melt faster in a warmer climate and is likely to be eliminated — except for residual glaciers in the mountains — if the annual average temperature in Greenland increases by more than about 3 °C. This would raise the global average sea-level by 7 metres over a period of 1000 years or more. We show here that concentrations of greenhouse gasses will probably have reached levels before the year 2100 that are sufficient to raise the temperature past this warming threshold."
85. ^ Record Arctic sea ice minimum confirmed by NSIDC
86. ^ Zhang, Jinlun; D.A. Rothrock (2003). "Modeling global sea ice with a thickness and enthalpy distribution model in generalized curvilinear coordinates". Mon. Wea. Rev. 131 (5): 681–697. Bibcode:2003MWRv..131..845Z. CiteSeerX 10.1.1.167.1046. doi:10.1175/1520-0493(2003)131<0845:MGSIWA>2.0.CO;2.
87. ^ Masters, Jeff (19 February 2013). "Arctic sea ice volume now one-fifth its 1979 level". weather underground. Archived from the original on 19 December 2013. Retrieved 14 September 2013.
88. ^ Overpeck, Jonathan T.; Sturm, Matthew; Francis, Jennifer A.; et al. (23 August 2005). "Arctic System on Trajectory to New, Seasonally Ice-Free State". Eos, Transactions, American Geophysical Union. 86 (34): 309–316. Bibcode:2005EOSTr..86..309O. doi:10.1029/2005EO340001.
89. ^ Butt, F. A.; H. Drange; A. Elverhoi; O. H. Ottera; A. Solheim (2002). "The Sensitivity of the North Atlantic Arctic Climate System to Isostatic Elevation Changes, Freshwater and Solar Forcings" (PDF). Quaternary Science Reviews. 21 (14–15): 1643–1660. doi:10.1016/S0277-3791(02)00018-5. OCLC 108566094. Archived from the original (PDF) on 10 September 2008.
90. ^ Reich, Katharine (15 November 2019). "Arctic Ocean could be ice-free for part of the year as soon as 2044". phys.org. Retrieved 3 September 2020.
91. ^ Kirby, Alex (11 August 2020). "End of Arctic sea ice by 2035 possible, study finds". Climate News Network. Retrieved 3 September 2020.
92. ^ IPCC AR4 chapter 10 [1] Table 10.7
93. ^ "Regional Sea Level Change". Intergovernmental Panel on Climate Change. Archived from the original (Figure 11.16) on 19 January 2017. Retrieved 4 April 2008.
94. ^ "NASA – Satellites See Unprecedented Greenland Ice Sheet Surface Melt". Archived from the original on 24 June 2023. Retrieved 4 November 2012.
95. ^ Velicogna, I. (2009). "Increasing rates of ice mass loss from the Greenland and Antarctic ice sheets revealed by GRACE". Geophysical Research Letters. 36 (19): L19503. Bibcode:2009GeoRL..3619503V. CiteSeerX 10.1.1.170.8753. doi:10.1029/2009GL040222. S2CID 14374232.
96. ^ a b "Ohio State University. "Warming Greenland ice sheet passes point of no return: Even if the climate cools, study finds, glaciers will continue to shrink."". ScienceDaily. Retrieved 1 September 2020.
97. ^ a b Pappas, Stephanie (17 August 2020). "Nothing will stop Greenland's ice sheet from shrinking now". Live Science. Retrieved 1 September 2020.
98. ^ "Climate change: Warmth shatters section of Greenland ice shelf". BBC. 14 September 2020.
99. ^ "A Top-Secret US Military Base Will Melt Out of the Greenland Ice Sheet". VICE Magazine. 9 March 2019.
100. ^ Laskow, Sarah (27 February 2018). "America's Secret Ice Base Won't Stay Frozen Forever". Wired. ISSN 1059-1028.
101. ^ Christensen, Torben R. (2004). "Thawing sub-arctic permafrost: Effects on vegetation and methane emissions". Geophysical Research Letters. 31 (4): L04501. Bibcode:2004GeoRL..31.4501C. doi:10.1029/2003gl018680. ISSN 0094-8276. S2CID 129023294.
102. ^ Bjorkman, Anne D.; García Criado, Mariana; Myers-Smith, Isla H.; Ravolainen, Virve; Jónsdóttir, Ingibjörg Svala; Westergaard, Kristine Bakke; Lawler, James P.; Aronsson, Mora; Bennett, Bruce; Gardfjell, Hans; Heiðmarsson, Starri (30 March 2019). "Status and trends in Arctic vegetation: Evidence from experimental warming and long-term monitoring". Ambio. 49 (3): 678–692. doi:10.1007/s13280-019-01161-6. ISSN 0044-7447. PMC 6989703. PMID 30929249.
103. ^ Gutman, G.Garik (February 1991). "Vegetation indices from AVHRR: An update and future prospects". Remote Sensing of Environment. 35 (2–3): 121–136. Bibcode:1991RSEnv..35..121G. doi:10.1016/0034-4257(91)90005-q. ISSN 0034-4257.
104. ^ a b c d Sonja, Myers-Smith, Isla H. Kerby, Jeffrey T. Phoenix, Gareth K. Bjerke, Jarle W. Epstein, Howard E. Assmann, Jakob J. John, Christian Andreu-Hayles, Laia Angers-Blondin, Sandra Beck, Pieter S. A. Berner, Logan T. Bhatt, Uma S. Bjorkman, Anne D. Blok, Daan Bryn, Anders Christiansen, Casper T. Cornelissen, J. Hans C. Cunliffe, Andrew M. Elmendorf, Sarah C. Forbes, Bruce C. Goetz, Scott J. Hollister, Robert D. de Jong, Rogier Loranty, Michael M. Macias-Fauria, Marc Maseyk, Kadmiel Normand, Signe Olofsson, Johan Parker, Thomas C. Parmentier, Frans-Jan W. Post, Eric Schaepman-Strub, Gabriela Stordal, Frode Sullivan, Patrick F. Thomas, Haydn J. D. Tommervik, Hans Treharne, Rachael Tweedie, Craig E. Walker, Donald A. Wilmking, Martin Wipf (2020). Complexity revealed in the greening of the Arctic. Umeå universitet, Institutionen för ekologi, miljö och geovetenskap. OCLC 1234747430.`{{cite book}}`: CS1 maint: multiple names: authors list (link)
105. ^ a b c Berner, Logan T.; Massey, Richard; Jantz, Patrick; Forbes, Bruce C.; Macias-Fauria, Marc; Myers-Smith, Isla; Kumpula, Timo; Gauthier, Gilles; Andreu-Hayles, Laia; Gaglioti, Benjamin V.; Burns, Patrick (December 2020). "Summer warming explains widespread but not uniform greening in the Arctic tundra biome". Nature Communications. 11 (1): 4621. Bibcode:2020NatCo..11.4621B. doi:10.1038/s41467-020-18479-5. ISSN 2041-1723. PMC 7509805. PMID 32963240.
106. ^ Martin, Andrew; Petrokofsky, Gillian (24 May 2018). "Shrub growth and expansion in the Arctic tundra: an assessment of controlling factors using an evidence-based approach". Proceedings of the 5th European Congress of Conservation Biology. Jyväskylä: Jyvaskyla University Open Science Centre. doi:10.17011/conference/eccb2018/108642. S2CID 134164370.
107. ^ Myers-Smith, Isla H.; Hik, David S. (25 September 2017). "Climate warming as a driver of tundra shrubline advance". Journal of Ecology. 106 (2): 547–560. doi:10.1111/1365-2745.12817. hdl:20.500.11820/f12e7d9d-1c24-4b5f-ad86-96715e071c7b. ISSN 0022-0477. S2CID 90390767.
108. ^ Alatalo, Juha M.; Jägerbrand, Annika K.; Molau, Ulf (14 August 2014). "Climate change and climatic events: community-, functional- and species-level responses of bryophytes and lichens to constant, stepwise, and pulse experimental warming in an alpine tundra". Alpine Botany. 124 (2): 81–91. doi:10.1007/s00035-014-0133-z. ISSN 1664-2201. S2CID 6665119.
109. ^ TAPE, KEN; STURM, MATTHEW; RACINE, CHARLES (24 March 2006). "The evidence for shrub expansion in Northern Alaska and the Pan-Arctic". Global Change Biology. 12 (4): 686–702. Bibcode:2006GCBio..12..686T. doi:10.1111/j.1365-2486.2006.01128.x. ISSN 1354-1013. S2CID 86278724.
110. ^ Alatalo, Juha M; Little, Chelsea J (22 March 2014). "Simulated global change: contrasting short and medium term growth and reproductive responses of a common alpine/Arctic cushion plant to experimental warming and nutrient enhancement". SpringerPlus. 3 (1): 157. doi:10.1186/2193-1801-3-157. ISSN 2193-1801. PMC 4000594. PMID 24790813.
111. ^ Loranty, Michael M; Goetz, Scott J; Beck, Pieter S A (1 April 2011). "Tundra vegetation effects on pan-Arctic albedo". Environmental Research Letters. 6 (2): 024014. Bibcode:2011ERL.....6b4014L. doi:10.1088/1748-9326/6/2/024014. ISSN 1748-9326. S2CID 250681995.
112. ^ a b c Belke-Brea, M.; Domine, F.; Barrere, M.; Picard, G.; Arnaud, L. (15 January 2020). "Impact of Shrubs on Winter Surface Albedo and Snow Specific Surface Area at a Low Arctic Site: In Situ Measurements and Simulations". Journal of Climate. 33 (2): 597–609. Bibcode:2020JCli...33..597B. doi:10.1175/jcli-d-19-0318.1. ISSN 0894-8755. S2CID 210295151.
113. ^ a b c Jeong, Su-Jong; Bloom, A. Anthony; Schimel, David; Sweeney, Colm; Parazoo, Nicholas C.; Medvigy, David; Schaepman-Strub, Gabriela; Zheng, Chunmiao; Schwalm, Christopher R.; Huntzinger, Deborah N.; Michalak, Anna M. (July 2018). "Accelerating rates of Arctic carbon cycling revealed by long-term atmospheric CO 2 measurements". Science Advances. 4 (7): eaao1167. Bibcode:2018SciA....4.1167J. doi:10.1126/sciadv.aao1167. ISSN 2375-2548. PMC 6040845. PMID 30009255.
114. ^ Martin, Andrew C.; Jeffers, Elizabeth S.; Petrokofsky, Gillian; Myers-Smith, Isla; Macias-Fauria, Marc (August 2017). "Shrub growth and expansion in the Arctic tundra: An assessment of controlling factors using an evidence-based approach". Environmental Research Letters. 12 (8): 085007. Bibcode:2017ERL....12h5007M. doi:10.1088/1748-9326/aa7989. S2CID 134164370.
115. ^ a b c Witze, Alexandra (10 September 2020). "The Arctic is burning like never before — and that's bad news for climate change". Nature. 585 (7825): 336–337. Bibcode:2020Natur.585..336W. doi:10.1038/d41586-020-02568-y. ISSN 0028-0836. PMID 32913318. S2CID 221625701.
116. ^ Lee, Sang H.; Whitledge, Terry E.; Kang, Sung-Ho (25 August 2009). "Carbon Uptake Rates of Sea Ice Algae and Phytoplankton under Different Light Intensities in a Landfast Sea Ice Zone, Barrow, Alaska". Arctic. 61 (3). doi:10.14430/arctic25. ISSN 1923-1245.
117. ^ Wu, Qiang (24 December 2019). "Satellite observations of unprecedented phytoplankton blooms in the Southern Ocean". The Cryosphere Discuss. doi:10.5194/tc-2019-282-sc1. S2CID 243147775.
118. ^ Struzik, Ed (14 February 2011). "Arctic Roamers: The Move of Southern Species into Far North". Environment360. Yale University. Retrieved 19 July 2016. "Grizzly bears mating with polar bears. Red foxes out-competing Arctic foxes. Exotic diseases making their way into once-isolated polar realms. These are just some of the worrisome phenomena now occurring as Arctic temperatures soar and the Arctic Ocean, a once-impermeable barrier, melts."
119. ^ "Protection For Polar Bears Urged By National Wildlife Federation". Science Daily. 3 April 2008. Retrieved 3 April 2008.
120. ^ DeWeaver, Eric; U.S. Geological Survey (2007). "Uncertainty in Climate Model Projections of Arctic Sea Ice Decline: An Evaluation Relevant to Polar Bears" (PDF). United States Department of the Interior. OCLC 183412441. Archived from the original (PDF) on 9 May 2009.
121. ^ Broder, John; Revkin, Andrew C. (8 July 2007). "Warming Is Seen as Wiping Out Most Polar Bears". The New York Times. Retrieved 23 September 2007.
122. ^ "Walruses in a Time of Climate Change". Arctic Program. 14 July 2016. Retrieved 19 May 2021.
123. ^ Descamps, Sébastien; Aars, Jon; Fuglei, Eva; Kovacs, Kit M.; Lydersen, Christian; Pavlova, Olga; Pedersen, Åshild Ø.; Ravolainen, Virve; Strøm, Hallvard (28 June 2016). "Climate change impacts on wildlife in a High Arctic archipelago – Svalbard, Norway". Global Change Biology. 23 (2): 490–502. doi:10.1111/gcb.13381. ISSN 1354-1013. PMID 27250039. S2CID 34897286.
124. ^ More Than 200 Reindeer Found Dead in Norway, Starved by Climate Change By Mindy Weisberger. Live Science, July 29, 2019
125. ^ Weiser, E.L.; Brown, S.C.; Lanctot, R.B.; River Gates, H.; Abraham, K.F.; et al. (2018). "Effects of environmental conditions on reproductive effort and nest success of Arctic-breeding shorebirds". Ibis. 160 (3): 608–623. doi:10.1111/ibi.12571. hdl:10919/99313. S2CID 53514207.
126. ^ "Terrestrial Permafrost". Arctic Program. 24 October 2017. Retrieved 18 May 2021.
127. ^ a b c Sayedi, Sayedeh Sara; Abbott, Benjamin W; Thornton, Brett F; Frederick, Jennifer M; Vonk, Jorien E; Overduin, Paul; Schädel, Christina; Schuur, Edward A G; Bourbonnais, Annie; Demidov, Nikita; Gavrilov, Anatoly (1 December 2020). "Subsea permafrost carbon stocks and climate change sensitivity estimated by expert assessment". Environmental Research Letters. 15 (12): B027-08. Bibcode:2020AGUFMB027...08S. doi:10.1088/1748-9326/abcc29. ISSN 1748-9326. S2CID 234515282.
128. ^ Hugelius, G.; Strauss, J.; Zubrzycki, S.; Harden, J. W.; Schuur, E. A. G.; Ping, C.-L.; Schirrmeister, L.; Grosse, G.; Michaelson, G. J.; Koven, C. D.; O'Donnell, J. A. (1 December 2014). "Estimated stocks of circumpolar permafrost carbon with quantified uncertainty ranges and identified data gaps". Biogeosciences. 11 (23): 6573–6593. Bibcode:2014BGeo...11.6573H. doi:10.5194/bg-11-6573-2014. ISSN 1726-4189. S2CID 14158339.
129. ^ "Permafrost and the Global Carbon Cycle". Arctic Program. 31 October 2019. Retrieved 18 May 2021.
130. ^ a b Douglas, Thomas A.; Turetsky, Merritt R.; Koven, Charles D. (24 July 2020). "Increased rainfall stimulates permafrost thaw across a variety of Interior Alaskan boreal ecosystems". npj Climate and Atmospheric Science. 3 (1): 5626. Bibcode:2020npCAS...3...28D. doi:10.1038/s41612-020-0130-4.
131. ^ Nowinski NS, Taneva L, Trumbore SE, Welker JM (January 2010). "Decomposition of old organic matter as a result of deeper active layers in a snow depth manipulation experiment". Oecologia. 163 (3): 785–92. Bibcode:2010Oecol.163..785N. doi:10.1007/s00442-009-1556-x. PMC 2886135. PMID 20084398.
132. ^ Schuur, E.A.G., Bockheim, J., Canadell, J.G., Euskirchen, E., Field, C.B., Goryachkin, S.V., Hagemann, S., Kuhry, P., Lafleur, P.M., Lee, H., Mazhitova, G., Nelson, F.E., Rinke, A., Romanovsky, V.E., Skiklomanov, N., Tarnocai, C., Venevsky, S., Vogel, J.G., and Zimov, S.A. (2008). "Vulnerability of Permafrost Carbon to Climate Change: Implications for the Global Carbon Cycle". BioScience. 58 (8): 701–714. doi:10.1641/B580807.`{{cite journal}}`: CS1 maint: multiple names: authors list (link)
133. ^ Lim, Artem G.; Loiko, Sergey V.; Pokrovsky, Oleg S. (10 January 2023). "Interactions between organic matter and Fe oxides at soil micro-interfaces: Quantification, associations, and influencing factors". Science of the Total Environment. 3: 158710. Bibcode:2023ScTEn.855o8710L. doi:10.1016/j.scitotenv.2022.158710. PMID 36099954. S2CID 252221350.
134. ^ Patzner, Monique S.; Mueller, Carsten W.; Malusova, Miroslava; Baur, Moritz; Nikeleit, Verena; Scholten, Thomas; Hoeschen, Carmen; Byrne, James M.; Borch, Thomas; Kappler, Andreas; Bryce, Casey (10 December 2020). "Iron mineral dissolution releases iron and associated organic carbon during permafrost thaw". Nature Communications. 11 (1): 6329. Bibcode:2020NatCo..11.6329P. doi:10.1038/s41467-020-20102-6. PMC 7729879. PMID 33303752.
135. ^ Bockheim, J.G. & Hinkel, K.M. (2007). "The importance of "Deep" organic carbon in permafrost-affected soils of Arctic Alaska". Soil Science Society of America Journal. 71 (6): 1889–92. Bibcode:2007SSASJ..71.1889B. doi:10.2136/sssaj2007.0070N. Archived from the original on 17 July 2009. Retrieved 5 June 2010.
136. ^ Lim, Artem G.; Loiko, Sergey V.; Pokrovsky, Oleg S. (2022). "Sizable pool of labile organic carbon in peat and mineral soils of permafrost peatlands, western Siberia". Geoderma. 409. Bibcode:2022Geode.409k5601L. doi:10.1016/j.geoderma.2021.115601.
137. ^ Gillis, Justin (16 December 2011). "As Permafrost Thaws, Scientists Study the Risks". The New York Times. Archived from the original on 19 May 2017. Retrieved 11 February 2017.
138. ^ Schellnhuber, Hans Joachim; Winkelmann, Ricarda; Scheffer, Marten; Lade, Steven J.; Fetzer, Ingo; Donges, Jonathan F.; Crucifix, Michel; Cornell, Sarah E.; Barnosky, Anthony D. (2018). "Trajectories of the Earth System in the Anthropocene". Proceedings of the National Academy of Sciences. 115 (33): 8252–8259. Bibcode:2018PNAS..115.8252S. doi:10.1073/pnas.1810141115. ISSN 0027-8424. PMC 6099852. PMID 30082409.
139. ^ MacDougall, Andrew H. (10 September 2021). "Estimated effect of the permafrost carbon feedback on the zero emissions commitment to climate change". Biogeosciences. 18 (17): 4937–4952. Bibcode:2021BGeo...18.4937M. doi:10.5194/bg-18-4937-2021.
140. ^ Sayedi, Sayedeh Sara; Abbott, Benjamin W; Thornton, Brett F; Frederick, Jennifer M; Vonk, Jorien E; Overduin, Paul; Schädel, Christina; Schuur, Edward A G; Bourbonnais, Annie; Demidov, Nikita; Gavrilov, Anatoly (1 December 2020). "Subsea permafrost carbon stocks and climate change sensitivity estimated by expert assessment". Environmental Research Letters. 15 (12): B027-08. Bibcode:2020AGUFMB027...08S. doi:10.1088/1748-9326/abcc29. ISSN 1748-9326. S2CID 234515282.
141. ^ Hugelius, Gustaf; Loisel, Julie; Chadburn, Sarah; et al. (10 August 2020). "Large stocks of peatland carbon and nitrogen are vulnerable to permafrost thaw". Proceedings of the National Academy of Sciences. 117 (34): 20438–20446. Bibcode:2020PNAS..11720438H. doi:10.1073/pnas.1916387117. PMC 7456150. PMID 32778585.
142. ^ a b Fox-Kemper, B., H.T. Hewitt, C. Xiao, G. Aðalgeirsdóttir, S.S. Drijfhout, T.L. Edwards, N.R. Golledge, M. Hemer, R.E. Kopp, G. Krinner, A. Mix, D. Notz, S. Nowicki, I.S. Nurhati, L. Ruiz, J.-B. Sallée, A.B.A. Slangen, and Y. Yu, 2021: Chapter 9: Ocean, Cryosphere and Sea Level Change. In Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Masson-Delmotte, V., P. Zhai, A. Pirani, S.L. Connors, C. Péan, S. Berger, N. Caud, Y. Chen, L. Goldfarb, M.I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J.B.R. Matthews, T.K. Maycock, T. Waterfield, O. Yelekçi, R. Yu, and B. Zhou (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 1211–1362, doi:10.1017/9781009157896.011.
143. ^ a b Schuur, Edward A.G.; Abbott, Benjamin W.; Commane, Roisin; Ernakovich, Jessica; Euskirchen, Eugenie; Hugelius, Gustaf; Grosse, Guido; Jones, Miriam; Koven, Charlie; Leshyk, Victor; Lawrence, David; Loranty, Michael M.; Mauritz, Marguerite; Olefeldt, David; Natali, Susan; Rodenhizer, Heidi; Salmon, Verity; Schädel, Christina; Strauss, Jens; Treat, Claire; Turetsky, Merritt (2022). "Permafrost and Climate Change: Carbon Cycle Feedbacks From the Warming Arctic". Annual Review of Environment and Resources. 47: 343–371. doi:10.1146/annurev-environ-012220-011847.
144. ^ Dietz, Simon; Rising, James; Stoerk, Thomas; Wagner, Gernot (24 August 2021). "Economic impacts of tipping points in the climate system". Proceedings of the National Academy of Sciences. 118 (34): e2103081118. Bibcode:2021PNAS..11803081D. doi:10.1073/pnas.2103081118. PMC 8403967. PMID 34400500.
145. ^ Keen, Steve; Lenton, Timothy M.; Garrett, Timothy J.; Rae, James W. B.; Hanley, Brian P.; Grasselli, Matheus (19 May 2022). "Estimates of economic and environmental damages from tipping points cannot be reconciled with the scientific literature". Proceedings of the National Academy of Sciences. 119 (21): e2117308119. Bibcode:2022PNAS..11917308K. doi:10.1073/pnas.2117308119. PMC 9173761. PMID 35588449. S2CID 248917625.
146. ^ Dietz, Simon; Rising, James; Stoerk, Thomas; Wagner, Gernot (19 May 2022). "Reply to Keen et al.: Dietz et al. modeling of climate tipping points is informative even if estimates are a probable lower bound". Proceedings of the National Academy of Sciences. 119 (21): e2201191119. Bibcode:2022PNAS..11901191D. doi:10.1073/pnas.2201191119. PMC 9173815. PMID 35588452.
147. ^ "Carbon Emissions from Permafrost". 50x30. 2021. Retrieved 8 October 2022.
148. ^ Natali, Susan M.; Holdren, John P.; Rogers, Brendan M.; Treharne, Rachael; Duffy, Philip B.; Pomerance, Rafe; MacDonald, Erin (10 December 2020). "Permafrost carbon feedbacks threaten global climate goals". Biological Sciences. 118 (21). doi:10.1073/pnas.2100163118. PMC 8166174. PMID 34001617.
149. ^ Armstrong McKay, David; Abrams, Jesse; Winkelmann, Ricarda; Sakschewski, Boris; Loriani, Sina; Fetzer, Ingo; Cornell, Sarah; Rockström, Johan; Staal, Arie; Lenton, Timothy (9 September 2022). "Exceeding 1.5°C global warming could trigger multiple climate tipping points". Science. 377 (6611): eabn7950. doi:10.1126/science.abn7950. hdl:10871/131584. ISSN 0036-8075. PMID 36074831. S2CID 252161375.
150. ^ Armstrong McKay, David (9 September 2022). "Exceeding 1.5°C global warming could trigger multiple climate tipping points – paper explainer". climatetippingpoints.info. Retrieved 2 October 2022.
151. ^ IPCC AR4 (2007). "Climate Change 2007: Working Group I: The Physical Science Basis". Archived from the original on 13 April 2014. Retrieved 12 April 2014.`{{cite web}}`: CS1 maint: numeric names: authors list (link)
152. ^ Shakhova, N.; Semiletov, I.; Panteleev, G. (2005). "The distribution of methane on the Siberian Arctic shelves: Implications for the marine methane cycle". Geophysical Research Letters. 32 (9): L09601. Bibcode:2005GeoRL..32.9601S. doi:10.1029/2005GL022751.
153. ^ Shakhova, Natalia; Semiletov, Igor; Leifer, Ira; Sergienko, Valentin; Salyuk, Anatoly; Kosmach, Denis; Chernykh, Denis; Stubbs, Chris; Nicolsky, Dmitry; Tumskoy, Vladimir; Gustafsson, Örjan (24 November 2013). "Ebullition and storm-induced methane release from the East Siberian Arctic Shelf" (PDF). Nature. 7 (1): 64–70. Bibcode:2014NatGe...7...64S. doi:10.1038/ngeo2007. Retrieved 12 April 2014.
154. ^ Shakhova, Natalia; Semiletov, Igor; Gustafsson, Orjan; Sergienko, Valentin; Lobkovsky, Leopold; Dudarev, Oleg; Tumskoy, Vladimir; Grigoriev, Michael; Mazurov, Alexey; Salyuk, Anatoly; Ananiev, Roman; Koshurnikov, Andrey; Kosmach, Denis; Charkin, Alexander; Dmitrevsky, Nicolay; Karnaukh, Victor; Gunar, Alexey; Meluzov, Alexander; Chernykh, Denis (2017). "Current rates and mechanisms of subsea permafrost degradation in the East Siberian Arctic Shelf". Nature Communications. 8: 15872. Bibcode:2017NatCo...815872S. doi:10.1038/ncomms15872. PMC 5489687. PMID 28639616.
155. ^ Shindell, Drew T.; Faluvegi, Greg; Koch, Dorothy M.; Schmidt, Gavin A.; Unger, Nadine; Bauer, Susanne E. (2009). "Improved attribution of climate forcing to emissions". Science. 326 (5953): 716–718. Bibcode:2009Sci...326..716S. doi:10.1126/science.1174760. PMID 19900930. S2CID 30881469.
156. ^ Kennett, James P.; Cannariato, Kevin G.; Hendy, Ingrid L.; Behl, Richard J. (2003). Methane Hydrates in Quaternary Climate Change: The Clathrate Gun Hypothesis. Washington DC: American Geophysical Union. doi:10.1029/054SP. ISBN 978-0-87590-296-8.
157. ^ Archer, D.; Buffett, B. (2005). "Time-dependent response of the global ocean clathrate reservoir to climatic and anthropogenic forcing" (PDF). Geochemistry, Geophysics, Geosystems. 6 (3): Q03002. Bibcode:2005GGG.....6.3002A. doi:10.1029/2004GC000854.
158. ^ a b Archer, D. (2007). "Methane hydrate stability and anthropogenic climate change" (PDF). Biogeosciences. 4 (4): 521–544. Bibcode:2007BGeo....4..521A. doi:10.5194/bg-4-521-2007. See also blog summary Archived 2007-04-15 at the Wayback Machine.
159. ^ Joung, DongJoo; Ruppel, Carolyn; Southon, John; Weber, Thomas S.; Kessler, John D. (17 October 2022). "Negligible atmospheric release of methane from decomposing hydrates in mid-latitude oceans". Nature Geoscience. 15 (11): 885–891. Bibcode:2022NatGe..15..885J. doi:10.1038/s41561-022-01044-8. S2CID 252976580.
160. ^ "Ancient ocean methane is not an immediate climate change threat". Phys.org. 18 October 2022. Retrieved 6 July 2023.
161. ^ Corbyn, Zoë (7 December 2012). "Locked greenhouse gas in Arctic sea may be 'climate canary'". Nature. doi:10.1038/nature.2012.11988. S2CID 130678063. Retrieved 12 April 2014.
162. ^ Shakhova, N.; Semiletov, I.; Panteleev, G. (2005). "The distribution of methane on the Siberian Arctic shelves: Implications for the marine methane cycle". Geophysical Research Letters. 32 (9): L09601. Bibcode:2005GeoRL..32.9601S. doi:10.1029/2005GL022751.
163. ^ "Arctic methane outgassing on the E Siberian Shelf part 1 - the background". SkepticalScience. 2012.
164. ^ "Climate-Hydrate Interactions". USGS. 14 January 2013.
165. ^ Shakhova, Natalia; Semiletov, Igor (30 November 2010). "Methane release from the East Siberian Arctic Shelf and the Potential for Abrupt Climate Change" (PDF). Retrieved 12 April 2014.
166. ^ a b "Methane bubbling through seafloor creates undersea hills" (Press release). Monterey Bay Aquarium Research Institute. 5 February 2007. Archived from the original on 11 October 2008.
167. ^ Shakhova, N.; Semiletov, I.; Salyuk, A.; Kosmach, D. (2008). "Anomalies of methane in the atmosphere over the East Siberian shelf: Is there any sign of methane leakage from shallow shelf hydrates?" (PDF). Geophysical Research Abstracts. 10: 01526. Archived from the original (PDF) on 22 December 2012. Retrieved 25 September 2008.
168. ^ Mrasek, Volker (17 April 2008). "A Storehouse of Greenhouse Gases Is Opening in Siberia". Spiegel International Online. "The Russian scientists have estimated what might happen when this Siberian permafrost-seal thaws completely and all the stored gas escapes. They believe the methane content of the planet's atmosphere would increase twelvefold."
169. ^ Preuss, Paul (17 September 2008). "IMPACTS: On the Threshold of Abrupt Climate Changes". Lawrence Berkeley National Laboratory.
170. ^ CCSP; et al. (2008). Abrupt Climate Change. A report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research. Clark. Reston VA: U.S. Geological Survey. Archived from the original on 4 May 2013.
171. ^ Atsushi Obata; Kiyotaka Shibata (20 June 2012). "Damage of Land Biosphere due to Intense Warming by 1000-Fold Rapid Increase in Atmospheric Methane: Estimation with a Climate–Carbon Cycle Model". J. Climate. 25 (24): 8524–8541. Bibcode:2012JCli...25.8524O. doi:10.1175/JCLI-D-11-00533.1.
172. ^ Sergienko, V. I.; et al. (September 2012). "The Degradation of Submarine Permafrost and the Destruction of Hydrates on the Shelf of East Arctic Seas as a Potential Cause of the 'Methane Catastrophe': Some Results of Integrated Studies in 2011" (PDF). Doklady Earth Sciences. 446 (1): 1132–1137. Bibcode:2012DokES.446.1132S. doi:10.1134/S1028334X12080144. ISSN 1028-334X. S2CID 129638485.
173. ^ a b Puglini, Matteo; Brovkin, Victor; Regnier, Pierre; Arndt, Sandra (26 June 2020). "Assessing the potential for non-turbulent methane escape from the East Siberian Arctic Shelf". Biogeosciences. 17 (12): 3247–3275. Bibcode:2020BGeo...17.3247P. doi:10.5194/bg-17-3247-2020. hdl:21.11116/0000-0003-FC9E-0. S2CID 198415071.
174. ^ Shakhova, N.; Semiletov, I.; Salyuk, A.; Kosmach, D.; Bel'cheva, N. (2007). "Methane release on the Arctic East Siberian shelf" (PDF). Geophysical Research Abstracts. 9: 01071.
175. ^ Connor, Steve (23 September 2008). "Exclusive: The methane time bomb". The Independent. Retrieved 3 October 2008.
176. ^ Connor, Steve (25 September 2008). "Hundreds of methane 'plumes' discovered". The Independent. Retrieved 3 October 2008.
177. ^ Translation of a blog entry by Örjan Gustafsson, expedition research leader, 2 September 2008
178. ^ Shakhova, Natalia; Semiletov, Igor; Leifer, Ira; Sergienko, Valentin; Salyuk, Anatoly; Kosmach, Denis; Chernykh, Denis; Stubbs, Chris; Nicolsky, Dmitry; Tumskoy, Vladimir; Gustafsson, Örjan (24 November 2013). "Ebullition and storm-induced methane release from the East Siberian Arctic Shelf". Nature. 7 (1): 64–70. Bibcode:2014NatGe...7...64S. doi:10.1038/ngeo2007.
179. ^ Thornton, Brett F.; Prytherch, John; Andersson, Kristian; Brooks, Ian M.; Salisbury, Dominic; Tjernström, Michael; Crill, Patrick M. (29 January 2020). "Shipborne eddy covariance observations of methane fluxes constrain Arctic sea emissions". Science Advances. 6 (5): eaay7934. Bibcode:2020SciA....6.7934T. doi:10.1126/sciadv.aay7934. PMC 6989137. PMID 32064354.
180. ^ CAGE (23 August 2017). "Study finds hydrate gun hypothesis unlikely". Phys.org.
181. ^ a b Wallmann; et al. (2018). "Gas hydrate dissociation off Svalbard induced by isostatic rebound rather than global warming". Nature Communications. 9 (1): 83. Bibcode:2018NatCo...9...83W. doi:10.1038/s41467-017-02550-9. PMC 5758787. PMID 29311564.
182. ^ Mau, S.; Römer, M.; Torres, M. E.; Bussmann, I.; Pape, T.; Damm, E.; Geprägs, P.; Wintersteller, P.; Hsu, C.-W.; Loher, M.; Bohrmann, G. (23 February 2017). "Widespread methane seepage along the continental margin off Svalbard - from Bjørnøya to Kongsfjorden". Scientific Reports. 7: 42997. Bibcode:2017NatSR...742997M. doi:10.1038/srep42997. PMC 5322355. PMID 28230189. S2CID 23568012.
183. ^ Silyakova, Anna; Jansson, Pär; Serov, Pavel; Ferré, Benedicte; Pavlov, Alexey K.; Hattermann, Tore; Graves, Carolyn A.; Platt, Stephen M.; Lund Myhre, Cathrine; Gründger, Friederike; Niemann, Helge (1 February 2020). "Physical controls of dynamics of methane venting from a shallow seep area west of Svalbard". Continental Shelf Research. 194: 104030. Bibcode:2020CSR...19404030S. doi:10.1016/j.csr.2019.104030. hdl:10037/16975. S2CID 214097236.
184. ^ Pohlman, John W.; Greinert, Jens; Ruppel, Carolyn; Silyakova, Anna; Vielstädte, Lisa; Casso, Michael; Mienert, Jürgen; Bünz, Stefan (1 February 2020). "Enhanced CO2 uptake at a shallow Arctic Ocean seep field overwhelms the positive warming potential of emitted methane". Biological Sciences. 114 (21): 5355–5360. doi:10.1073/pnas.1618926114. PMC 5448205. PMID 28484018.
185. ^ Schellnhuber, Hans Joachim; Winkelmann, Ricarda; Scheffer, Marten; Lade, Steven J.; Fetzer, Ingo; Donges, Jonathan F.; Crucifix, Michel; Cornell, Sarah E.; Barnosky, Anthony D. (2018). "Trajectories of the Earth System in the Anthropocene". Proceedings of the National Academy of Sciences. 115 (33): 8252–8259. Bibcode:2018PNAS..115.8252S. doi:10.1073/pnas.1810141115. ISSN 0027-8424. PMC 6099852. PMID 30082409.
186. ^ a b Fox-Kemper, B.; Hewitt, H.T.; Xiao, C.; Aðalgeirsdóttir, G.; Drijfhout, S.S.; Edwards, T.L.; Golledge, N.R.; Hemer, M.; Kopp, R.E.; Krinner, G.; Mix, A. (2021). Masson-Delmotte, V.; Zhai, P.; Pirani, A.; Connors, S.L.; Péan, C.; Berger, S.; Caud, N.; Chen, Y.; Goldfarb, L. (eds.). "Chapter 5: Global Carbon and other Biogeochemical Cycles and Feedbacks" (PDF). Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK and New York, NY, USA: 5. doi:10.1017/9781009157896.011.
187. ^ Moskvitch, Katia (2014). "Mysterious Siberian crater attributed to methane". Nature. doi:10.1038/nature.2014.15649. S2CID 131534214. Archived from the original on 19 November 2014. Retrieved 4 August 2014.
188. ^ Armstrong McKay, David; Abrams, Jesse; Winkelmann, Ricarda; Sakschewski, Boris; Loriani, Sina; Fetzer, Ingo; Cornell, Sarah; Rockström, Johan; Staal, Arie; Lenton, Timothy (9 September 2022). "Exceeding 1.5°C global warming could trigger multiple climate tipping points". Science. 377 (6611): eabn7950. doi:10.1126/science.abn7950. hdl:10871/131584. ISSN 0036-8075. PMID 36074831. S2CID 252161375.
189. ^ Armstrong McKay, David (9 September 2022). "Exceeding 1.5°C global warming could trigger multiple climate tipping points – paper explainer". climatetippingpoints.info. Retrieved 2 October 2022.
190. ^ Hill, Christopher (15 June 2015). Abrupt Climate Change and the Atlantic Meridional Overturning Circulation: sensitivity and non-linear response to Arctic/sub-Arctic freshwater pulses. Collaborative research. Final report (Report). doi:10.2172/1184378. OSTI 1184378.
191. ^ a b Nelson, Daniel (19 April 2018). "The Gulf Stream May Be Weaker Than It Has Been In 1600 Years, Could Exacerbate Climate Change". Science Trends. doi:10.31988/scitrends.15937.
192. ^ Vaughan, Adam (November 2020). "Arctic ice loss could trigger huge extra global warming". New Scientist. 248 (3307): 21. Bibcode:2020NewSc.248...21V. doi:10.1016/s0262-4079(20)31956-4. ISSN 0262-4079. S2CID 228974766.
193. ^ Chen, Xi; et al. (12 November 2020). "Supplemental Material: Zinc isotope evidence for paleoenvironmental changes during Cretaceous Oceanic Anoxic Event 2". Geology. doi:10.1130/geol.s.13232360.v1. S2CID 240757224. Retrieved 19 May 2021.
194. ^ Francis, Jennifer A.; Vavrus, Stephen J. (2012). "Evidence linking Arctic amplification to extreme weather in mid-latitudes". Geophysical Research Letters. 39 (6): L06801. Bibcode:2012GeoRL..39.6801F. CiteSeerX 10.1.1.419.8599. doi:10.1029/2012GL051000. S2CID 15383119.
195. ^ Zielinski, G.; Mershon, G. (1997). "Paleoenvironmental implications of the insoluble microparticle record in the GISP2 (Greenland) ice core during the rapidly changing climate of the Pleistocene-Holocene transition". Bulletin of the Geological Society of America. 109 (5): 547–559. Bibcode:1997GSAB..109..547Z. doi:10.1130/0016-7606(1997)109<0547:piotim>2.3.co;2.
196. ^ Lue, J.-M.; Kim, S.-J.; Abe-Ouchi, A.; Yu, Y.; Ohgaito, R. (2010). "Arctic Oscillation during the Mid-Holocene and Last Glacial Maximum from PMIP2 Coupled Model Simulations". Journal of Climate. 23 (14): 3792–3813. Bibcode:2010JCli...23.3792L. doi:10.1175/2010JCLI3331.1. S2CID 129156297.
197. ^ Mitchell, Daniel M.; Osprey, Scott M.; Gray, Lesley J.; Butchart, Neal; Hardiman, Steven C.; Charlton-Perez, Andrew J.; Watson, Peter (August 2012). "The Effect of Climate Change on the Variability of the Northern Hemisphere Stratospheric Polar Vortex". Journal of the Atmospheric Sciences. 69 (8): 2608–2618. Bibcode:2012JAtS...69.2608M. doi:10.1175/jas-d-12-021.1. ISSN 0022-4928. S2CID 122783377.
198. ^ Masato, Giacomo; Hoskins, Brian J.; Woollings, Tim (2013). "Winter and Summer Northern Hemisphere Blocking in CMIP5 Models". Journal of Climate. 26 (18): 7044–7059. Bibcode:2013JCli...26.7044M. doi:10.1175/JCLI-D-12-00466.1.
199. ^ Liu, Jiping; Curry, Judith A.; Wang, Huijun; Song, Mirong; Horton, Radley M. (27 February 2012). "Impact of declining Arctic sea ice on winter snowfall". PNAS. 109 (11): 4074–4079. Bibcode:2012PNAS..109.4074L. doi:10.1073/pnas.1114910109. PMC 3306672. PMID 22371563.
200. ^ Qiuhong Tang; Xuejun Zhang; Francis, J. A. (December 2013). "Extreme summer weather in northern mid-latitudes linked to a vanishing cryosphere". Nature Climate Change. 4 (1): 45–50. Bibcode:2014NatCC...4...45T. doi:10.1038/nclimate2065.
201. ^ Screen, J A (November 2013). "Influence of Arctic sea ice on European summer precipitation". Environmental Research Letters. 8 (4): 044015. Bibcode:2013ERL.....8d4015S. doi:10.1088/1748-9326/8/4/044015. hdl:10871/14835.
202. ^ Friedlander, Blaine (4 March 2013). "Arctic ice loss amplified Superstorm Sandy violence". Cornell Chronicle. Retrieved 7 January 2014.
203. ^ Walsh, Bryan (6 January 2014). "Polar Vortex: Climate Change Might Just Be Driving the Historic Cold Snap". Time. Retrieved 7 January 2014.
204. ^ Spotts, Pete (6 January 2014). "How frigid 'polar vortex' could be result of global warming (+video)". The Christian Science Monitor. Retrieved 8 January 2014.
205. ^ Jennifer Francis; Natasa Skific (1 June 2015). "Evidence linking rapid Arctic warming to mid-latitude weather patterns". Philosophical Transactions. 373 (2045): 20140170. Bibcode:2015RSPTA.37340170F. doi:10.1098/rsta.2014.0170. PMC 4455715. PMID 26032322.
206. ^ Mann, Michael E.; Rahmstorf, Stefan (27 March 2017). "Influence of Anthropogenic Climate Change on Planetary Wave Resonance and Extreme Weather Events". Scientific Reports. 7: 45242. Bibcode:2017NatSR...745242M. doi:10.1038/srep45242. PMC 5366916. PMID 28345645.
207. ^ "Extreme global weather is 'the face of climate change' says leading scientist". The Guardian. 2018.
208. ^ Francis J; Vavrus S; Cohen J. (2017). "Amplified Arctic warming and mid latitude weather: new perspectives on emerging connections" (PDF). Wiley Interdisciplinary Reviews: Climate Change. 8 (5). 2017 Wiley Periodicals,Inc: e474. Bibcode:2017WIRCC...8E.474F. doi:10.1002/wcc.474.
209. ^ Fischetti, Mark (2017). "The Arctic Is Getting Crazy". Scientific American.
210. ^ Kretschmer, Marlene; Coumou, Dim; Agel, Laurie; Barlow, Mathew; Tziperman, Eli; Cohen, Judah (January 2018). "More-Persistent Weak Stratospheric Polar Vortex States Linked to Cold Extremes" (PDF). Bulletin of the American Meteorological Society. 99 (1): 49–60. Bibcode:2018BAMS...99...49K. doi:10.1175/bams-d-16-0259.1. ISSN 0003-0007. S2CID 51847061.
211. ^ Coumou, D.; Di Capua, G.; Vavrus, S.; Wang, L.; Wang, S. (20 August 2018). "The influence of Arctic amplification on mid-latitude summer circulation". Nature Communications. 9 (1): 2959. Bibcode:2018NatCo...9.2959C. doi:10.1038/s41467-018-05256-8. ISSN 2041-1723. PMC 6102303. PMID 30127423.
212. ^ Kim, Jin-Soo; Kug, Jong-Seong; Jeong, Su-Jong; Huntzinger, Deborah N.; Michalak, Anna M.; Schwalm, Christopher R.; Wei, Yaxing; Schaefer, Kevin (26 October 2021). "Reduced North American terrestrial primary productivity linked to anomalous Arctic warming". Nature Geoscience. 10 (8): 572–576. doi:10.1038/ngeo2986. OSTI 1394479.
213. ^ "Climate change: Arctic warming linked to colder winters". BBC News. 2 September 2021. Retrieved 20 October 2021.
214. ^ Cohen, Judah; Agel, Laurie; Barlow, Mathew; Garfinkel, Chaim I.; White, Ian (3 September 2021). "Linking Arctic variability and change with extreme winter weather in the United States". Science. 373 (6559): 1116–1121. Bibcode:2021Sci...373.1116C. doi:10.1126/science.abi9167. PMID 34516838. S2CID 237402139.
215. ^ Zou, Yofei; Rasch, Philip J.; Wang, Hailong; Xie, Zuowei; Zhang, Rudong (26 October 2021). "Increasing large wildfires over the western United States linked to diminishing sea ice in the Arctic". Nature Communications. 12 (1): 6048. Bibcode:2021NatCo..12.6048Z. doi:10.1038/s41467-021-26232-9. PMC 8548308. PMID 34702824. S2CID 233618492.
216. ^ Weng, H. (2012). "Impacts of multi-scale solar activity on climate. Part I: Atmospheric circulation patterns and climate extremes". Advances in Atmospheric Sciences. 29 (4): 867–886. Bibcode:2012AdAtS..29..867W. doi:10.1007/s00376-012-1238-1. S2CID 123066849.
217. ^ James E. Overland (8 December 2013). "Atmospheric science: Long-range linkage". Nature Climate Change. 4 (1): 11–12. Bibcode:2014NatCC...4...11O. doi:10.1038/nclimate2079.
218. ^ Seviour, William J.M. (14 April 2017). "Weakening and shift of the Arctic stratospheric polar vortex: Internal variability or forced response?". Geophysical Research Letters. 44 (7): 3365–3373. Bibcode:2017GeoRL..44.3365S. doi:10.1002/2017GL073071. hdl:1983/caf74781-222b-4735-b171-8842cead4086. S2CID 131938684.
219. ^ Screen, James A. (15 June 2014). "Arctic amplification decreases temperature variance in northern mid- to high-latitudes". Nature Climate Change. 4 (7): 577–582. Bibcode:2014NatCC...4..577S. doi:10.1038/nclimate2268. hdl:10871/15095.
220. ^ van Oldenborgh, Geert Jan; Mitchell-Larson, Eli; Vecchi, Gabriel A.; de Vries, Hylke; Vautar, Robert; Otto, Friederike (22 November 2019). "Cold waves are getting milder in the northern midlatitudes". Environmental Research Letters. 14 (11): 114004. Bibcode:2019ERL....14k4004V. doi:10.1088/1748-9326/ab4867. S2CID 204420462.
221. ^ Blackport, Russell; Screen, James A.; van der Wiel, Karin; Bintanja, Richard (September 2019). "Minimal influence of reduced Arctic sea ice on coincident cold winters in mid-latitudes". Nature Climate Change. 9 (9): 697–704. Bibcode:2019NatCC...9..697B. doi:10.1038/s41558-019-0551-4. hdl:10871/39784. S2CID 199542188.
222. ^ Blackport, Russell; Screen, James A. (February 2020). "Insignificant effect of Arctic amplification on the amplitude of midlatitude atmospheric waves". Science Advances. 6 (8): eaay2880. Bibcode:2020SciA....6.2880B. doi:10.1126/sciadv.aay2880. PMC 7030927. PMID 32128402.
223. ^ Streffing, Jan; Semmler, Tido; Zampieri, Lorenzo; Jung, Thomas (24 September 2021). "Response of Northern Hemisphere Weather and Climate to Arctic Sea Ice Decline: Resolution Independence in Polar Amplification Model Intercomparison Project (PAMIP) Simulations". Journal of Climate. 34 (20): 8445–8457. Bibcode:2021JCli...34.8445S. doi:10.1175/JCLI-D-19-1005.1. S2CID 239631549.
224. ^ Paul Voosen (12 May 2021). "Landmark study casts doubt on controversial theory linking melting Arctic to severe winter weather". Science Magazine. Retrieved 7 October 2022.
225. ^ Smith, D.M.; Eade, R.; Andrews, M.B.; et al. (7 February 2022). "Robust but weak winter atmospheric circulation response to future Arctic sea ice loss". Nature Communications. 13 (1): 727. Bibcode:2022NatCo..13..727S. doi:10.1038/s41467-022-28283-y. PMC 8821642. PMID 35132058. S2CID 246637132.
226. ^ Eckel, Mike (20 September 2007). "Russia: Tests Show Arctic Ridge Is Ours". The Washington Post. Associated Press. Retrieved 21 September 2007.[dead link]
227. ^ a b c d e f "Territorial Claims in the Arctic Circle: An Explainer". The Observer. Retrieved 19 May 2021.
228. ^ a b c "Evolution of Arctic Territorial Claims and Agreements: A Timeline (1903–Present) • Stimson Center". Stimson Center. 15 September 2013. Retrieved 19 May 2021.
229. ^ a b c d e f g h Hassol, Susan Joy (2004). Impacts of a warming Arctic (Reprinted ed.). Cambridge, UK: Cambridge University Press. ISBN 978-0-521-61778-9.
230. ^ a b Berkes, Fikret; Jolly, Dyanna (2001). "Adapting to climate change: social-ecological resilience in a Canadian western Arctic community" (PDF). Conservation Ecology. 5 (2).
231. ^ a b Farquhar, Samantha D. (18 March 2020). "Inuit Seal Hunting in Canada: Emerging Narratives in an Old Controversy". Arctic. 73 (1): 13–19. doi:10.14430/arctic69833. ISSN 1923-1245. S2CID 216308832.
232. ^ Timonin, Andrey (2021). "Climate Change in the Arctic and Future Directions for Adaptation: Views From Non-Arctic States". SSRN Electronic Journal. doi:10.2139/ssrn.3802303. ISSN 1556-5068. S2CID 233756936.
233. ^ Rogers, Sarah (13 June 2014). "New online atlas tracks Nunavut's centuries-old Inuit trails". Nunatsiaq News. Retrieved 19 May 2021.
234. ^ Humpert, Malte; Raspotnik, Andreas (2012). "The Future of Shipping Along the Transpolar Sea Route" (PDF). The Arctic Yearbook. 1 (1): 281–307. Archived from the original (PDF) on 21 January 2016. Retrieved 18 November 2015.
235. ^ "As The Earth Warms, The Lure Of The Arctic's Natural Resources Grows". 18 March 2019.
236. ^ Byers, Michael. "Melting Arctic brings new opportunities". aljazeera.com.
237. ^ Bekkers, Eddy; Francois, Joseph F.; Rojas-Romagosa, Hugo (1 December 2016). "Melting Ice Caps and the Economic Impact of Opening the Northern Sea Route" (PDF). The Economic Journal. 128 (610): 1095–1127. doi:10.1111/ecoj.12460. ISSN 1468-0297. S2CID 55162828.
238. ^ "ESA's ice mission CryoSat-2". esa.int. 11 September 2008. Retrieved 15 June 2009.
239. ^ Wininger, Corinne (26 October 2007). "E SF, VR, FORMAS sign MOU to promote Global Environmental Change Research". innovations-report.de. Retrieved 26 November 2007.
240. ^ "Arctic Change". International Study of Arctic Change.

### Works cited[edit]

* IPCC (2021). Masson-Delmotte, V.; Zhai, P.; Pirani, A.; Connors, S. L.; et al. (eds.). Climate Change 2021: The Physical Science Basis (PDF). Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press (In Press).
* Fox-Kemper, Baylor; Hewitt, Helene T.; Xiao, Cunde; Aðalgeirsdóttir, Guðfinna; et al. (2021). "Chapter 9: Ocean, cryosphere, and sea level change" (PDF). IPCC AR6 WG1 2021.

## Further reading[edit]

* "Black Carbon and Methane". Arctic Council. 9 July 2018. Retrieved 6 November 2023.

* Hersher, Rebecca (11 August 2022). "The Arctic is heating up nearly four times faster than the whole planet, study finds". NPR. Retrieved 6 November 2023.

## External links[edit]

* Arctic Change website, in near-realtime
* Arctic Sea Ice News & Analysis
* Smith, Duane (2007). "Climate Change In The Arctic: An Inuit Reality". UN Chronicle.
* The Arctic ice sheet, satellite map with daily updates.
* NOAA: Arctic Theme Page – A comprehensive resource focused on the Arctic
* Persistent warming trend and loss of sea ice are triggering extensive Arctic changes (Report). Arctic Report Card: Update for 2016. NOAA.
* Rapid and pronounced warming continues to drive the evolution of the Arctic environment (Report). Arctic Report Card: Update for 2021. NOAA.
* Killing the Arctic Origins: Current Events in Historical Perspective (October 2020), by John McCannon

* v
* t
* e

Arctic topics

History|

* Arctic exploration
* Arctic research
* History of whaling

Government|

* Arctic Council
* Arctic cooperation and politics
* Arctic Ocean Conference
* Chief Directorate of the Northern Sea Route
* Ilulissat Declaration
* Inuit Circumpolar Council
* Saami Council
* Territorial claims in the Arctic
* United Nations Convention on the Law of the Sea

Geography|

* Arctic Archipelago
* Arctic Circle
* Arctic Cordillera
* Arctic ecology
* Arctic Ocean
* Arctic Cyclone
* Greenland ice sheet
* Impact craters of the Arctic
* Innuitian Region
* Nordicity
* North Pole
* Populated places in the Arctic
* Tundra

Geology|

* Canadian Arctic Rift System
* Eurekan orogeny
* Greenland Plate
* Innuitian orogeny
* Queen Elizabeth Islands Subplate
* Southeast Bathurst Fault Zone
* Ungava Fault Zone

Regions|

* Arctic Alaska
* British Arctic Territories
* Canadian Arctic Archipelago
* Finnmark
* Greenland
* Iceland
* Inuvialuit
* Karelia
* Komi
* Northern Canada
* Northwest Territories
* Nunavik
* Nunavut
* Nunatsiavut
* Russian Arctic
* Sakha
* Sápmi
* Yukon
* North American Arctic

Climate|

* Arctic Climate Impact Assessment
* Arctic dipole anomaly
* Arctic haze
* Arctic oscillation
* Arctic sea ice
* decline
* ecology and history
* Arctic methane emissions
* Climate change in the Arctic
* Climate of Alaska
* Effects of global warming on marine mammals
* Polar climate
* Polar amplification
* Polar vortex

Fauna|

* Arctic fox
* Beluga whale
* Bowhead whale
* Lemming
* Muskox
* Narwhal
* Polar bear
* Reindeer
* Seal
* bearded
* harp
* hooded
* ribbon
* ringed
* Snowy owl
* Walrus

Flora|

* Arctic ecology
* Arctic vegetation
* Tundra

Culture|

* Arctic peoples
* Subarctic peoples
* Chukchi
* Chukotka
* Evenks
* Karelians
* Komi
* Icelandic
* Inuit
* Gwich'in
* Khanty
* Koryaks
* Nenets
* Northern indigenous Russian peoples
* Sami
* Selkup
* Yakuts
* Yukaghir
* Arctic Winter Games
* Quviasukvik (New Year's Day)

Economy|

* Natural resources
* Petroleum exploration
* Arctic Refuge drilling controversy
* Pollution in the Arctic Ocean
* Protected areas
* Transportation

Transport|

* Arctic Bridge
* Arctic shipping routes
* Northeast Passage
* Northwest Passage
* Northern Sea Route
* Polar air route
* Transpolar Sea Route
* Search and rescue

* Category
* WikiProject

* v
* t
* e

Climate change

Overview

* Causes of climate change
* Climate change adaptation
* Climate change mitigation
* Climate system
* Effects of climate change
* By country and region

Causes

| Overview|

* Carbon dioxide in Earth's atmosphere
* Greenhouse effect
* Scientific consensus on climate change

|

Sources|

* Deforestation
* Fossil fuel
* Greenhouse gases
* Greenhouse gas emissions
* Carbon accounting
* Carbon footprint
* Carbon leakage
* from agriculture
* from wetlands
* World energy supply and consumption

History

* History of climate change policy and politics
* History of climate change science
* Svante Arrhenius
* James Hansen
* Charles David Keeling
* United Nations Climate Change conferences
* Years in climate change
* 2019
* 2020
* 2021
* 2022
* 2023
* 2024

Effects and issues

| Physical|

* Abrupt climate change
* Anoxic event
* Arctic methane emissions
* Arctic sea ice decline
* Atlantic meridional overturning circulation
* Drought
* Extreme weather
* Flood
* Coastal flooding
* Heat wave
* Marine
* Urban heat island
* Oceans
* acidification
* deoxygenation
* heat content
* sea surface temperature
* stratification
* temperature
* Ozone depletion
* Permafrost thaw
* Retreat of glaciers since 1850
* Sea level rise
* Season creep
* Tipping points in the climate system
* Tropical cyclones
* Water cycle
* Wildfires

|

Flora and fauna|

* Biomes
* Mass mortality event
* Birds
* Extinction risk
* Forest dieback
* Invasive species
* Marine life
* Plant biodiversity

Social and economic|

* Agriculture
* Livestock
* Children
* Cities
* Civilizational collapse
* Disability
* Economic impacts
* Fisheries
* Gender
* Health
* Mental health
* Human rights
* Indigenous peoples
* Infectious diseases
* Migration
* Poverty
* Psychological impacts
* Security and conflict
* Urban flooding
* Water scarcity
* Water security

By country and region|

* Africa
* Americas
* Antarctica
* Arctic
* Asia
* Australia
* Caribbean
* Europe
* Middle East and North Africa
* Small island countries
* South Asia
* by individual country

Mitigation

| Economics and finance|

* Carbon budget
* Carbon emission trading
* Carbon offsets and credits
* Gold Standard (carbon offset standard)
* Carbon price
* Carbon tax
* Climate debt
* Climate finance
* Climate risk insurance
* Co-benefits of climate change mitigation
* Economics of climate change mitigation
* Fossil fuel divestment
* Green Climate Fund
* Low-carbon economy
* Net zero emissions

|

Energy|

* Carbon capture and storage
* Energy transition
* Fossil fuel phase-out
* Nuclear power
* Renewable energy
* Sustainable energy

Preserving and enhancing
carbon sinks|

* Blue carbon
* Carbon dioxide removal
* Carbon sequestration
* Direct air capture
* Carbon farming
* Climate-smart agriculture
* Forest management
* afforestation
* forestry for carbon sequestration
* REDD and REDD+
* reforestation
* Land use, land-use change, and forestry (LULUCF and AFOLU)
* Nature-based solutions

Personal|

* Individual action on climate change
* Plant-based diet

Society and adaptation

| Society|

* Business action
* Climate action
* Climate emergency declaration
* Climate movement
* School Strike for Climate
* Denial
* Ecological grief
* Governance
* Justice
* Litigation
* Politics
* Public opinion
* Women

|

Adaptation|

* Adaptation strategies on the German coast
* Adaptive capacity
* Disaster risk reduction
* Ecosystem-based adaptation
* Flood control
* Loss and damage
* Managed retreat
* Nature-based solutions
* Resilience
* Risk
* Vulnerability
* The Adaptation Fund
* National Adaptation Programme of Action

Communication|

* Climate Change Performance Index
* Climate crisis (term)
* Climate spiral
* Education
* Media coverage
* Popular culture depictions
* art
* fiction
* video games
* Warming stripes

International agreements|

* Glasgow Climate Pact
* Kyoto Protocol
* Paris Agreement
* Cooperative Mechanisms under Article 6 of the Paris Agreement
* Nationally determined contributions
* Sustainable Development Goal 13
* United Nations Framework Convention on Climate Change

Background and theory

| Measurements|

* Global surface temperature
* Instrumental temperature record
* Proxy
* Satellite temperature measurement

|

Theory|

* Albedo
* Carbon cycle
* atmospheric
* biologic
* oceanic
* permafrost
* Carbon sink
* Climate sensitivity
* Climate variability and change
* Cloud feedback
* Cloud forcing
* Fixed anvil temperature hypothesis
* Cryosphere
* Earth's energy budget
* Extreme event attribution
* Feedbacks
* Global warming potential
* Illustrative model of greenhouse effect on climate change
* Orbital forcing
* Radiative forcing

Research and modelling|

* Climate change scenario
* Climate model
* Coupled Model Intercomparison Project
* Intergovernmental Panel on Climate Change (IPCC)
* IPCC Sixth Assessment Report
* Paleoclimatology
* Paleotempestology
* Representative Concentration Pathway
* Shared Socioeconomic Pathways
* Solar radiation modification

* Climate change portal
* Category
* Glossary
* Index

*[v]: View this template
*[t]: Discuss this template
*[e]: Edit this template