The Antarctic Treaty and related agreements, collectively known as the Antarctic Treaty System (ATS), regulate international relations with respect to Antarctica, Earth's only continent without a native human population. It was the first arms control agreement established during the Cold War, designating the continent as a scientific preserve, establishing freedom of scientific investigation, and banning military activity; for the purposes of the treaty system, Antarctica is defined as all the land and ice shelves south of 60°S latitude. Since September 2004, the Antarctic Treaty Secretariat, which implements the treaty system, is headquartered in Buenos Aires, Argentina.
The main treaty was opened for signature on 1 December 1959, and officially entered into force on 23 June 1961. The original signatories were the 12 countries active in Antarctica during the International Geophysical Year (IGY) of 1957–58: Argentina, Australia, Belgium, Chile, France, Japan, New Zealand, Norway, South Africa, the Soviet Union, the United Kingdom, and the United States. These countries had established over 55 Antarctic research stations
for the IGY, and the subsequent promulgation of the treaty was seen as a
diplomatic expression of the operational and scientific cooperation
that had been achieved. As of 2024, the treaty has 58 parties.
History
Map of research stations and territorial claims in Antarctica (2015)
1940s
After World War II, the U.S. considered establishing a claim in Antarctica. From 26 August 1946, and until the beginning of 1947, it carried out Operation Highjump,
the largest military expeditionary force that the United States had
ever sent to Antarctica, consisting of 13 ships, 4,700 men, and numerous
aerial devices. Its goals were to train military personnel and to test material in
conditions of extreme cold for a hypothetical war in the Antarctic.
On 2 September 1947, the quadrant of Antarctica in which the United States was interested (between 24° W and 90° W) was included as part of the security zone of the Inter-American Treaty of Reciprocal Assistance, committing its members to defend it in case of external aggression.
In August 1948, the United States proposed that Antarctica be
under the guardianship of the United Nations, as a trust territory
administered by Argentina, Australia, Chile, France, the United States,
the United Kingdom, and New Zealand. This idea was rejected by
Argentina, Australia, Chile, France, and Norway. Before the rejection,
on 28 August 1948, the United States proposed to the claimant countries
some form of internationalization
of Antarctica, and the United Kingdom supported this. Chile responded
by presenting a plan to suspend all Antarctic claims for five to ten
years while negotiating a final solution, but this did not find
acceptance.
In 1950, the interest of the United States to keep the Soviet
Union away from Antarctica was frustrated, when the Soviets informed the
claimant states that they would not accept any Antarctic agreement in
which they were not represented. The fear that the USSR would react by
making a territorial claim, bringing the Cold War to Antarctica, led the
United States to make none.
International conflicts
Various international conflicts motivated the creation of an agreement for the Antarctic.
Some incidents had occurred during the Second World War, and a new one occurred in Hope Bay
on 1 February 1952, when the Argentine military fired warning shots at a
group of Britons. The response of the United Kingdom was to send a
warship that landed marines at the scene on 4 February. In 1949, Argentina, Chile, and the United Kingdom signed a Tripartite
Naval Declaration committing not to send warships south of the 60th parallel south,
which was renewed annually until 1961 when it was deemed unnecessary
when the treaty entered into force. This tripartite declaration was
signed after the tension generated when Argentina sent a fleet of eight
warships to Antarctica in February 1948.
On 17 January 1953, Argentina reopened the Lieutenant Lasala refuge on Deception Island,
leaving a sergeant and a corporal in the Argentine Navy. On 15
February, in the incident on Deception Island, 32 royal marines landed
from the British frigate HMS Snipe armed with Sten
machine guns, rifles, and tear gas capturing the two Argentine sailors.
The Argentine refuge and a nearby uninhabited Chilean shelter were
destroyed, and the Argentine sailors were delivered to a ship from that
country on 18 February near South Georgia. A British detachment remained three months on the island while the frigate patrolled its waters until April.
On 4 May 1955, the United Kingdom filed two lawsuits, against Argentina and Chile respectively, before the International Court of Justice
to declare the invalidity of the claims of the sovereignty of the two
countries over Antarctic and sub-Antarctic areas. On 15 July 1955, the
Chilean government rejected the jurisdiction of the court in that case,
and on 1 August, the Argentine government also did so, so on 16 March
1956, the claims were closed.
In 1950, the International Council of Scientific Unions (ICSU) had discussed the possibility of holding a third International Polar Year. At the suggestion of the World Meteorological Organization, the idea of the International Polar Year was extended to the entire planet, thus creating the International Geophysical Year
that took place between 1 July 1957, and 31 December 1958. In this
event, 66 countries participated. At the ICSU meeting in Stockholm from 9
to 11 September 1957, the creation of a Special Committee for Antarctic
Research (SCAR) was approved, inviting the twelve countries conducting
Antarctic investigations to send delegates to integrate the committee,
with the purpose of exchanging scientific information among its members
regarding Antarctica. The SCAR was later renamed to the Scientific
Committee for Research in Antarctica.
Both Argentina and Chile stated that research carried out on the
continent during the International Geophysical Year would not give any
territorial rights to the participants, and that the facilities that
were erected during that year should be dismantled at the end of it.
However, in February 1958, the United States proposed that the Antarctic
investigations should be extended for another year, and the Soviet
Union reported that it would maintain its scientific bases until the
studies being carried out had been completed.
Negotiation of the treaty
Scientific
bases increased international tension concerning Antarctica. The danger
of the Cold War spreading to that continent caused the President of the
United States, Dwight D. Eisenhower,
to convene an Antarctic Conference of the twelve countries active in
Antarctica during the International Geophysical Year, to sign a treaty.
In the first phase, representatives of the twelve nations met in
Washington, who met in sixty sessions between June 1958 and October 1959
to define a basic negotiating framework. However, no consensus was
reached on a preliminary draft. In the second phase, a conference at the
highest diplomatic level was held from 15 October to 1 December 1959,
when the Treaty was signed.
The Antarctic Treaty was signed in 1959 by 12 nations and came
into effect on 23 June 1961. The central ideas with full acceptance were
the freedom of scientific research in Antarctica and the peaceful use
of the continent. There was also a consensus for demilitarization and
the maintenance of the status quo. The treaty prohibits nuclear testing,
military operations, economic exploitation, and territorial claims in
Antarctica. It is monitored through on-site inspections. The only
permanent structures allowed are scientific research stations. The
original signatory countries hold voting rights on Antarctic governance,
with seven of them claiming portions of the continent and the remaining
five being non-claimants. Other nations have joined as consultative
members by conducting significant research in Antarctica.
Non-consultative parties can also adhere to the treaty. In 1991–1992,
the treaty was renegotiated by 33 nations, with the main change being
the Madrid Protocol on Environmental Protection, which prohibited mining
and oil exploration for 50 years.
The positions of the United States, the Soviet Union, the United
Kingdom, and New Zealand coincided in the establishment of an
international administration for Antarctica, proposing that it should be
within the framework of the United Nations. Australia and the United
Kingdom expressed the need for inspections by observers, and the British
also proposed the use of military personnel for logistical functions.
Argentina proposed that all atomic explosions be banned in Antarctica,
which caused a crisis that lasted until the last day of the conference,
since the United States, along with other countries, intended to ban
only those that were made without prior notice and without prior
consultation. The support of the USSR and Chile for the Argentine
proposal finally caused the United States to retract its opposition.
The signing of the treaty was the first arms control agreement
that occurred in the framework of the Cold War, and the participating
countries managed to avoid the internationalization of Antarctic sovereignty.
Starting from the year 2048, any of the consultative parties to
the treaty may request the revision of the treaty and its entire
normative system, with the approval of a three-quarters majority of consultative parties needed for the adoption of any changes.
Other agreements
Disposal of waste by simply dumping it at the shoreline, as at the Russian Bellingshausen Station on King George Island, is no longer permitted by the Protocol on Environmental Protection.
Other agreements – some 200 recommendations adopted at treaty consultative meetings and ratified by governments – include:
The Protocol on Environmental Protection to the Antarctic Treaty
was signed 4 October 1991, and entered into force 14 January 1998; this
agreement prevents development and provides for the protection of the
Antarctic environment through five specific annexes on marine pollution, fauna and flora, environmental impact assessments, waste management,
and protected areas. It prohibits all activities relating to mineral
resources except scientific. A sixth annex on liability arising from
environmental emergencies was adopted in 2005, but is yet to enter into
force.
Bilateral treaties
Exchange
of Notes constituting an Agreement between the Governments of
Australia, New Zealand and the United Kingdom of Great Britain and
Northern Ireland, and the Government of the French Republic, regarding
Aerial Navigation in the Antarctic (Paris, 25 October 1938)
Treaty Between the Government of Australia and the Government of the
French Republic on Cooperation in the Maritime Areas Adjacent to the
French Southern and Antarctic Territories (TAAF), Heard Island and the
McDonald Islands (Canberra, 24 November 2003)
Agreement on Cooperative Enforcement of Fisheries Laws between the
Government of Australia and the Government of the French Republic in the
Maritime Areas Adjacent to the French Southern and Antarctic
Territories, Heard Island and the McDonald Islands (Paris, 8 January
2007)
Meetings
The Antarctic Treaty System's yearly Antarctic Treaty Consultative Meetings (ATCM)
are the international forum for the administration and management of
the region. Only 29 of the 58 parties to the agreements have the right
to participate in decision-making at these meetings, though the other 29
are still allowed to attend. The decision-making participants are the Consultative Parties
and, in addition to the 12 original signatories, including 17 countries
that have demonstrated their interest in Antarctica by carrying out
substantial scientific activity there. The Antarctic Treaty also has Special Antarctic Treaty Consultative Meetings (SATCM), which are generally summoned to treat more important topics but are less frequents and Meetings of Experts.
Parties
As of 2024, there are 58 states party to the treaty, 29 of which, including all 12 original signatories to the treaty, have consultative (voting) status. The consultative members include the 7 countries that claim portions of
Antarctica as their territory. The 51 non-claimant countries do not
recognize the claims of others. 42 parties to the Antarctic Treaty have
also ratified the "Protocol on Environmental Protection to the Antarctic
Treaty".
The Antarctic Treaty Secretariat was established in Buenos
Aires, Argentina in September 2004 by the Antarctic Treaty Consultative
Meeting (ATCM). Jan Huber (the Netherlands) served as the first
Executive Secretary for five years until 31 August 2009. He was
succeeded on 1 September 2009, by Manfred Reinke (Germany). Reinke was
succeeded by Albert Lluberas (Uruguay), who was elected in June 2017 at
the 40th Antarctic Consultative Treaty Meeting in Beijing, China.
The tasks of the Antarctic Treaty Secretariat can be divided into the following areas:
Supporting the annual Antarctic Treaty Consultative Meeting
(ATCM) and the meeting of the Committee for Environmental Protection
(CEP).
Facilitating the exchange of information between the Parties required in the Treaty and the Environment Protocol.
Collecting, storing, arranging and publishing the documents of the ATCM.
Providing and disseminating public information about the Antarctic Treaty system and Antarctic activities.
Legal system
Antarctica
currently has no permanent population and therefore it has no
citizenship nor government. Personnel present on Antarctica at any time
are always citizens or nationals of some sovereignty outside Antarctica,
as there is no Antarctic sovereignty. The majority of Antarctica is
claimed by one or more countries, but most countries do not explicitly
recognize those claims. The area on the mainland between 90 degrees west and 150 degrees west is the only major land on Earth not claimed by any country. Until 2015 the interior of the Norwegian Sector, the extent of which had never been officially defined, was considered to be unclaimed. That year, Norway formally laid claim to the area between its Queen Maud Land and the South Pole.
Governments that are party to the Antarctic Treaty and its
Protocol on Environmental Protection implement the articles of these
agreements, and decisions taken under them, through national laws. These
laws generally apply only to their own citizens, wherever they are in
Antarctica, and serve to enforce the consensus decisions of the
consultative parties: about which activities are acceptable, which areas
require permits to enter, what processes of environmental impact
assessment must precede activities, and so on. The Antarctic Treaty is
often considered to represent an example of the common heritage of mankind principle.
Australia
This 1959 cover commemorated the opening of the Wilkes post office in the Australian Antarctic Territory.
Since the designation of the Australian Antarctic Territory
pre-dated the signing of the Antarctic Treaty, Australian laws that
relate to Antarctica date from more than two decades before the
Antarctic Treaty era. In terms of criminal law, the laws that apply to
the Jervis Bay Territory (which follows the laws of the Australian Capital Territory)
apply to the Australian Antarctic Territory. Key Australian legislation
applying Antarctic Treaty System decisions include the Antarctic Treaty Act 1960, the Antarctic Treaty (Environment Protection) Act 1980 and the Antarctic Marine Living Resources Conservation Act 1981.
United States
The law of the United States,
including certain criminal offences by or against U.S. nationals, such
as murder, may apply to areas not under jurisdiction of other countries.
To this end, the United States now stations special deputy U.S. Marshals in Antarctica to provide a law enforcement presence.
Some U.S. laws directly apply to Antarctica. For example, the Antarctic Conservation Act, Public Law 95-541, 16 U.S.C.§ 2401et seq., provides civil and criminal penalties for the following activities, unless authorized by regulation or statute:
the taking of native Antarctic mammals or birds
the introduction into Antarctica of non-indigenous plants and animals
entry into specially protected or scientific areas
the discharge or disposal of pollutants into Antarctica or Antarctic waters
the importation into the U.S. of certain items from Antarctica
In
2006, the New Zealand police reported that jurisdictional issues
prevented them issuing warrants for potential American witnesses who
were reluctant to testify during the Christchurch Coroner's investigation into the death by poisoning of Australian astrophysicist Rodney Marks at the South Pole base in May 2000. Marks died while wintering over at the United States' Amundsen–Scott South Pole Station located at the geographic South Pole. Prior to autopsy, the death was attributed to natural causes by the National Science Foundation and the contractor administering the base. However, an autopsy in New Zealand revealed that Marks died from methanol poisoning. The New Zealand Police
launched an investigation. In 2006, frustrated by lack of progress, the
Christchurch Coroner said that it was unlikely that Marks ingested the
methanol knowingly, although there is no certainty that he died as the
direct result of the act of another person. During media interviews, the
police detective in charge of the investigation criticized the National
Science Foundation and contractor Raytheon for failing to cooperate with the investigation.
South Africa
Under the South African Citizens in Antarctica Act, 1962, South African law applies to all South African citizens in Antarctica, and they are subject to the jurisdiction of the magistrate's court in Cape Town. The Antarctic Treaties Act, 1996
incorporates the Antarctic Treaty and related agreements into South
African law. In regard to violations of these treaties, South Africa
also asserts jurisdiction over South African residents and members of
expeditions organised in South Africa.
Due to climate change in the Arctic, this polar region is expected to become "profoundly different" by 2050. The speed of change is "among the highest in the world", with warming occurring at 3-4 times faster than the global average. This warming has already resulted in the profound Arctic sea ice decline, the accelerating melting of the Greenland ice sheet and the thawing of the permafrost landscape. These ongoing transformations are expected to be irreversible for centuries or even millennia.
Natural life in the Arctic is affected greatly. As the tundra warms, its soil becomes more hospitable to earthworms and larger plants, and the boreal forests spread to the north - yet this also makes the landscape more prone to wildfires, which take longer to recover from than in the other regions. Beavers also take advantage of this warming to colonize the Arctic rivers, and their dams contributing to methane emissions due to the increase in stagnant waters. The Arctic Ocean has experienced a large increase in the marine primary production as warmer waters and less shade from sea ice benefit phytoplankton. At the same time, it is already less alkaline than the rest of the global ocean, so ocean acidification caused by the increasing CO2 concentrations is more severe, threatening some forms of zooplankton such as pteropods.
The Arctic Ocean is expected to see its first ice-free events in
the near future - most likely before 2050, and potentially in the late
2020s or early 2030s. This would have no precedent in the last 700,000 years. Some sea ice regrows every Arctic winter, but such events are expected
to occur more and more frequently as the warming increases. This has
great implications for the fauna species which are dependent on sea ice, such as polar bears. For humans, trade routes across the ocean will become more convenient. Yet, multiple countries have infrastructure
in the Arctic which is worth billions of dollars, and it is threatened
with collapse as the underlying permafrost thaws. The Arctic's
indigenous people have a long relationship with its icy conditions, and
face the loss of their cultural heritage.
Further, there are numerous implications which go beyond the
Arctic region. Sea ice loss not only enhances warming in the Arctic but
also adds to global temperature increase through the ice-albedo feedback. Permafrost thaw results in emissions of CO2 and methane that are comparable to those of major countries. Greenland melting is a significant contributor to global sea level rise.
If the warming exceeds - or thereabouts, there is a significant risk of
the entire ice sheet being lost over an estimated 10,000 years, adding
up to global sea levels. Warming in the Arctic may affect the stability
of the jet stream, and thus the extreme weather events in midlatitude regions, but there is only "low confidence" in that hypothesis.
Impacts on the physical environment
Warming
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).
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. Alaska and western Canada's temperature rose by 3 to 4 °C (5.40 to 7.20 °F) during that period. 2013 research 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. Since 2013, Arctic annual mean surface air temperature (SAT) has been at least 1 °C (1.8 °F) warmer than the 1981-2010 mean.
In 2016, there were extreme anomalies from January to February
with the temperature in the Arctic being estimated to be between
4–5.8 °C (7.2–10.4 °F) more than it was between 1981 and 2010. In 2020, mean SAT was 1.9 °C (3.4 °F) warmer than the 1981–2010 average. 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 (18.0 °F) higher than
normal. 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.
Arctic amplification
Potential
regional warming caused by the loss of all land ice outside of East
Antarctica, and by the disappearance of Arctic sea ice every year
starting from June. While plausible, consistent sea ice loss would
likely require relatively high warming, and the loss of all ice in
Greenland would require multiple millennia.
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. 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.
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. 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. 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.
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 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). 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.
The dark ocean surface reflects only 6 percent of incoming solar radiation, while sea ice reflects 50 to 70 percent.
The Arctic was historically described as warming twice as fast as the global average, 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. 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.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. 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.
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. 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. The second acceleration has no known cause, 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), 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. Recent studies show the Arctic has warmed nearly four times faster than
the global average since 1979, with areas like the Barents Sea
experiencing rates up to seven times higher, highlighting the urgent
need to address polar climate change.
Precipitation
An
observed impact of climate change is a strong increase in the number of
lightnings in the Arctic. Lightnings increase the risk for wildfires. Some research suggests that globally, a warming greater than 1.5 °C
(2.7 °F) over the preindustrial level could change the type of
precipitation in the Arctic from snow to rain in summer and autumn.
Cryosphere loss
On average, climate change has lowered the thickness of land ice with every year, and reduced the extent of sea ice cover.
Sea ice
1870–2009 Northern Hemisphere sea ice extent in million square kilometers. Blue shading indicates the pre-satellite era; data then is less reliable.
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). Summertime sea ice will likely cease to exist sometime during the 21st century.
The region is at its warmest in at least 4,000 years. Furthermore, 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. 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. 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. 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.
Greenland ice sheet
2023
projections of how much the Greenland ice sheet may shrink from its
present extent by the year 2300 under the worst possible climate change
scenario (upper half) and of how much faster its remaining ice will be
flowing in that case (lower half)
The Greenland ice sheet is an ice sheet
which forms the second largest body of ice in the world. It is an
average of 1.67 km (1.0 mi) thick and over 3 km (1.9 mi) thick at its
maximum. It is almost 2,900 kilometres (1,800 mi) long in a north–south
direction, with a maximum width of 1,100 kilometres (680 mi) at a
latitude of 77°N, near its northern edge. The ice sheet covers 1,710,000 square kilometres (660,000 sq mi), around 80% of the surface of Greenland, or about 12% of the area of the Antarctic ice sheet. The term 'Greenland ice sheet' is often shortened to GIS or GrIS in scientific literature.
Greenland has had major glaciers and ice caps for at least 18 million years, but a single ice sheet first covered most of the island some 2.6 million years ago. Since then, it has both grown and contracted significantly. The oldest known ice on Greenland is about 1 million years old. Due to anthropogenic greenhouse gas emissions, the ice sheet is now the warmest it has been in the past 1000 years, and is losing ice at the fastest rate in at least the past 12,000 years.
Every summer, parts of the surface melt and ice cliffs calve into the sea. Normally the ice sheet would be replenished by winter snowfall, but due to global warming the ice sheet is melting two to five times faster than before 1850, and snowfall has not kept up since 1996. If the Paris Agreement goal of staying below 2 °C (3.6 °F) is achieved, melting of Greenland ice alone would still add around 6 cm (2+1⁄2 in) to global sea level rise by the end of the century. If there are no reductions in emissions, melting would add around 13 cm (5 in) by 2100, with a worst-case of about 33 cm (13 in). For comparison, melting has so far contributed 1.4 cm (1⁄2 in) since 1972, while sea level rise from all sources was 15–25 cm (6–10 in) between 1901 and 2018.
Lakes
A January 2025 study published in the Proceedings of the National Academy of Sciences
reported an "abrupt, coherent, climate-driven transformation" from
"blue" (more transparent) to "brown" (less transparent) states of lakes
in Greenland after a season of both record heat and rainfall drove a state change in these systems. This change was said to alter "numerous physical, chemical, and
biological lake features", and the state changes were said to be
unprecedented.
Biological environment
Impacts on Arctic flora
Western Hemisphere Arctic Vegetation Index TrendEastern 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. NASA and NOAA have continuously monitored Arctic vegetation with satellite instruments such as Moderate Resolution Imaging Spectroradiometer (MODIS) and Advanced very-high-resolution radiometer (AVHRR). Their data allows scientists to calculate so-called "Arctic greening" and "Arctic browning". 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 the sites -
typically the ones that were still experiencing cooling and drying, as
opposed to warming and wettening for the rest.
This expansion of vegetation in the Arctic is not equivalent across types of vegetation. A major trend has been from shrub-type
plants 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. 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. 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.
The expansion of these shrubs can also have strong effects on other important ecological dynamics, such as the albedo effect. These shrubs change the winter surface of the tundra from undisturbed,
uniform snow to mixed surface with protruding branches disrupting the
snow cover, 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. 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. 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. 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. 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.
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. 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.
Impacts on terrestrial fauna
Projected change in polar bear habitat from 2001–2010 to 2041–2050
Arctic warming negatively affects the foraging and breeding ecology of native Arctic mammals, such as Arctic foxes or Arctic reindeer. In July 2019, 200 Svalbard reindeer were found starved to death apparently due to low precipitation related to climate change. This was only one episode in the long-term decline of the species.United States Geological Survey research suggests that the shrinkage of Arctic sea ice would eventually extirpate polar bears from Alaska, but leave some of their habitat in the Canadian Arctic Archipelago and areas off the northern Greenland coast.
As the pure Arctic climate is gradually replaced by the subarctic climate, animals adapted to those conditions spread to the north. For instance, beavers have been actively colonizing Arctic regions, and as they create dams, they flood areas which used to be permafrost, contributing to its thaw and methane emissions from it. These colonizing species can outright replace native species, and they
may also interbreed with their southern relations, like in the case of
the Grizzly–polar bear hybrid. This usually has the effect of reducing the genetic diversity of the genus. Infectious diseases, such as brucellosis or phocine distemper virus, may spread to populations previously separated by the cold, or, in case of the marine mammals, the sea ice.
Marine ecosystems
The observed increase in phytoplankton biomass in the Arctic since 1998
The reduction of sea ice has brought more sunlight to the phytoplankton and increased the annual marine primary production in the Arctic by over 30% between 1998 and 2020. As the result, the Arctic Ocean became a stronger carbon sink over this period; yet, it still accounts for only 5% to 14% of the total ocean carbon
sink, although it is expected to play a larger role in the future. By 2100, phytoplankton biomass
in the Arctic Ocean is generally expected to increase by ~20% relative
to 2000 under the low-emission scenario, and by 30-40% under the
high-emission scenario.
Atlantic cod have been able to move deeper into the Arctic due to the warming waters, while the Polar cod and local marine mammals have been losing habitat. Many copepod species appear to be declining, which is also likely to reduce the numbers of fish which prey on them, such as walleye pollock or the arrowtooth flounder. This also affects Arctic shorebirds. For instance, around 9000 puffins and other shorebirds in Alaska died of starvation in 2016, because too many fish have moved to the north. While the shorebirds also appear to nest more successfully due to the observed warming, this benefit may be more than offset by phenological mismatch between shorebirds' and other species' life cycles. Marine mammals such as ringed seals and walruses are also being negatively affected by the warming.
In 2024, the Arctic has transformed from a carbon sink to a carbon
source due to the impacts of climate change, mainly rising temperatures
and wildfires.
Permafrost is an important component of hydrological systems and ecosystems within the Arctic landscape. In the Northern Hemisphere the terrestrial permafrost domain comprises around 18 million km2. 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.
In 2023, Woodwell Climate Research Center received a $5 million grant and fellowship from Google.org,
the philanthropic arm of Google, to develop an open-access resource
that will use satellite data and artificial intelligence in order to
track Arctic permafrost thaw in near real-time.
As recent warming deepens the active layer subject to permafrost thaw, this exposes formerly stored carbon to biogenic processes which facilitate its entrance into the atmosphere as carbon dioxide and methane. Because carbon emissions from permafrost thaw contribute to the same
warming which facilitates the thaw, it is a well-known example of a positive climate change feedback. Permafrost thaw is sometimes included as one of the major tipping points in the climate system due to the exhibition of local thresholds and its effective irreversibility. However, while there are self-perpetuating processes that apply on the
local or regional scale, it is debated as to whether it meets the strict
definition of a global tipping point as in aggregate permafrost thaw is
gradual with warming.
In the northern circumpolar region, permafrost contains organic matter
equivalent to 1400–1650 billion tons of pure carbon, which was built up
over thousands of years. This amount equals almost half of all organic
material in all soils,and it is about twice the carbon content of the atmosphere, or around four times larger than the human emissions of carbon between the start of the Industrial Revolution and 2011. Further, most of this carbon (~1,035 billion tons) is stored in what is
defined as the near-surface permafrost, no deeper than 3 metres
(9.8 ft) below the surface. However, only a fraction of this stored carbon is expected to enter the atmosphere. In general, the volume of permafrost in the upper 3 m of ground is
expected to decrease by about 25% per 1 °C (1.8 °F) of global warming, yet even under the RCP8.5 scenario associated with over 4 °C (7.2 °F) of global warming by the end of the 21st century, about 5% to 15% of permafrost carbon is expected to be lost "over decades and centuries".
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.
Altogether, it is expected that cumulative greenhouse gas emissions
from permafrost thaw will be smaller than the cumulative anthropogenic
emissions, yet still substantial on a global scale, with some experts
comparing them to emissions caused by deforestation. 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. For comparison, by 2019, annual anthropogenic emissions of carbon dioxide alone stood around 40 billion tonnes.
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 approach year 2019
emissions of China.
Fewer studies have attempted to describe the impact directly in terms of
warming. A 2018 paper estimated that if global warming was limited to
2 °C (3.6 °F), gradual permafrost thaw would add around 0.09 °C
(0.16 °F) to global temperatures by 2100, while a 2022 review concluded that every 1 °C (1.8 °F) of global
warming would cause 0.04 °C (0.072 °F) and 0.11 °C (0.20 °F) from abrupt
thaw by the year 2100 and 2300. Around 4 °C (7.2 °F) of global warming,
abrupt (around 50 years) and widespread collapse of permafrost areas
could occur, resulting in an additional warming of 0.2–0.4 °C
(0.36–0.72 °F).
Black carbon
Black
carbon emissions from fire and human activities around the Arctic in
the year 2012, as measured from a research station in Abisko
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. A 2013 study quantified that gas flaring at petroleum extraction sites contributed over 40% of the black carbon deposited in the Arctic 2019 research attributed the majority (56%) of Arctic surface black
carbon to emissions from Russia, followed by European emissions, and
Asia also being a large source. In 2015, research suggested that reducing black carbon emissions and
short-lived greenhouse gases by roughly 60 percent by 2050 could cool
the Arctic up to 0.2 °C. However, a 2019 study indicates that "Black carbon emissions will
continuously rise due to increased shipping activities", specifically
fishing vessels.
The number of wildfires in the Arctic Circle has increased. In 2020, Arctic wildfire CO2 emissions broke a new record, peaking at 244 megatonnes of carbon dioxide emitted. 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. 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. The smoke from wildfires defined as "brown carbon"
also increases arctic warming, with its warming effect is around 30%
that of black carbon. As wildfires increases with warming this creates a
positive feedback loop.
Methane clathrate deposits
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). It is further proposed that these warming events caused the Bond cycles and individual interstadial events, such as the Dansgaard–Oeschger interstadials.
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. 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." The report had also linked terrestrial hydrate deposits to gas emission craters discovered in the Yamal Peninsula in Siberia, Russia beginning in July 2014, but noted that since terrestrial gas hydrates predominantly form at a
depth below 200 meters, a substantial response within the next few
centuries can be ruled out. Likewise, a 2022 assessment of tipping points described methane
hydrates as a "threshold-free feedback" rather than a tipping point.
Effects on other parts of the world
On ocean circulation
Modelled 21st century warming under the "intermediate" global warming scenario (top). The potential collapse of the subpolar gyre in this scenario (middle). The collapse of the entire Atlantic Meriditional Overturning Circulation (bottom).
The AMOC has not always existed; for much of Earth's history,
overturning circulation in the northern hemisphere occurred in the North
Pacific. Paleoclimate evidence shows the shift of overturning
circulation from the Pacific to the Atlantic occurred 34 million years
ago at the Eocene-Oligocene transition, when the Arctic-Atlantic gateway had closed. This closure fundamentally changed the thermohaline circulation structure; some researchers have suggested climate change may eventually reverse this shift and re-establish the Pacific circulation after the AMOC shuts down. Climate change affects the AMOC by making surface water warmer as a consequence of Earth's energy imbalance
and by making surface water less saline due to the addition of large
quantities of fresh water from melting ice – mainly from Greenland – and
through increasing precipitation over the North Atlantic. Both of these
causes would increase the difference between the surface and deep
layers, thus making the upwelling and downwelling that drives the
circulation more difficult.
Severe weakening of the AMOC may lead to a collapse of the circulation,
which would not be easily reversible and thus constitutes one of the tipping points in the climate system. A collapse would substantially lower the average temperature and amount of rain and snowfall in Europe. It may also raise the frequency of extreme weather events and have other severe effects.
In 2021, the IPCC Sixth Assessment Report
again said the AMOC is "very likely" to decline within the 21st century
and that there was a "high confidence" changes to it would be
reversible within centuries if warming was reversed. Unlike the Fifth Assessment Report, it had only "medium confidence"
rather than "high confidence" in the AMOC avoiding a collapse before the
end of the 21st century. This reduction in confidence was likely
influenced by several review studies that draw attention to the
circulation stability bias within general circulation models, and simplified ocean-modelling studies suggesting the AMOC may be more
vulnerable to abrupt change than larger-scale models suggest.
The synthesis report of the IPCC Sixth Assessment Report summarized the
scientific consensus as follows: "The Atlantic Meridional Overturning
Circulation is very likely to weaken over the 21st century for all
considered scenarios (high confidence), however an abrupt collapse is
not expected before 2100 (medium confidence). If such a low probability
event were to occur, it would very likely cause abrupt shifts in
regional weather patterns and water cycle, such as a southward shift in
the tropical rain belt, and large impacts on ecosystems and human
activities."
On mid-latitude weather
Since the early 2000s, climate models have consistently identified that global warming
will gradually push jet streams poleward. In 2008, this was confirmed
by observational evidence, which proved that from 1979 to 2001, the
northern jet stream moved northward at an average rate of 2.01
kilometres (1.25 mi) per year, with a similar trend in the southern
hemisphere jet stream.Climate scientists have hypothesized that the jet stream will also
gradually weaken as a result of global warming. Trends such as Arctic sea ice decline, reduced snow cover, evapotranspiration
patterns, and other weather anomalies have caused the Arctic to heat up
faster than other parts of the globe, in what is known as the Arctic amplification. In 2021–2022, it was found that since 1979, the warming within the Arctic Circle has been nearly four times faster than the global average, and some hotspots in the Barents Sea area warmed up to seven times faster than the global average. While the Arctic remains one of the coldest places on Earth today, the
temperature gradient between it and the warmer parts of the globe will
continue to diminish with every decade of global warming as the result
of this 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.
The hypothesis above is closely associated with Jennifer Francis, who had first proposed it in a 2012 paper co-authored by Stephen J. Vavrus. 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, this was contradicted by climate modelling, with PMIP2 simulations finding in 2010 that the Arctic Oscillation (AO) 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. 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.", 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, and other 2012 research had suggested a connection between declining
Arctic sea ice and heavy snowfall during midlatitude winters.
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. This point was stressed by reviews in 2013 and in 2017. 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. 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.
Moreover, a range of long-term observational data collected during the
2010s and published in 2020 suggests that the intensification of Arctic
amplification since the early 2010s was not linked to significant
changes on mid-latitude atmospheric patterns.State-of-the-art modelling research of PAMIP (Polar Amplification Model
Intercomparison Project) improved upon the 2010 findings of PMIP2; it
found 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. 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.
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.
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.
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.
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.
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. Another example is that of the Northwest Passage, globally recognized as international waters, but technically in Canadian waters. 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.
Navigation
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.
Governments and private industry have shown a growing interest in the Arctic. 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. 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. Finding and controlling these resources will be difficult with the continually moving ice. Tourism may also increase as less sea ice will improve safety and accessibility to the Arctic.
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."
Infrastructure
Map of likely risk to infrastructure from permafrost thaw expected to occur by 2050.
As of 2021, there are 1162 settlements located directly atop the
Arctic permafrost, which host an estimated 5 million people. By 2050,
permafrost layer below 42% of these settlements is expected to thaw,
affecting all their inhabitants (currently 3.3 million people). Consequently, a wide range of infrastructure in permafrost areas is threatened by the thaw. By 2050, it's estimated that nearly 70% of global infrastructure
located in the permafrost areas would be at high risk of permafrost
thaw, including 30–50% of "critical" infrastructure. The associated
costs could reach tens of billions of dollars by the second half of the
century. Reducing greenhouse gas emissions in line with the Paris Agreement is projected to stabilize the risk after mid-century; otherwise, it'll continue to worsen.
In Alaska alone, damages to infrastructure by the end of the century would amount to $4.6 billion (at 2015 dollar value) if RCP8.5, the high-emission climate change scenario,
were realized. Over half stems from the damage to buildings
($2.8 billion), but there's also damage to roads ($700 million),
railroads ($620 million), airports ($360 million) and pipelines ($170 million). Similar estimates were done for RCP4.5, a less intense scenario which
leads to around 2.5 °C (4.5 °F) by 2100, a level of warming similar to
the current projections. In that case, total damages from permafrost thaw are reduced to
$3 billion, while damages to roads and railroads are lessened by
approximately two-thirds (from $700 and $620 million to $190 and
$220 million) and damages to pipelines are reduced more than ten-fold,
from $170 million to $16 million. Unlike the other costs stemming from
climate change in Alaska, such as damages from increased precipitation and flooding, climate change adaptation
is not a viable way to reduce damages from permafrost thaw, as it would
cost more than the damage incurred under either scenario.
In Canada, Northwest Territories
have a population of only 45,000 people in 33 communities, yet
permafrost thaw is expected to cost them $1.3 billion over 75 years, or
around $51 million a year. In 2006, the cost of adapting Inuvialuit homes to permafrost thaw was estimated at $208/m2 if they were built at pile foundations, and $1,000/m2 if they didn't. At the time, the average area of a residential building in the territory was around 100 m2. Thaw-induced damage is also unlikely to be covered by home insurance,
and to address this reality, territorial government currently funds
Contributing Assistance for Repairs and Enhancements (CARE) and Securing
Assistance for Emergencies (SAFE) programs, which provide long- and
short-term forgivable loans to help homeowners adapt. It is possible
that in the future, mandatory relocation would instead take place as the
cheaper option. However, it would effectively tear the local Inuit
away from their ancestral homelands. Right now, their average personal
income is only half that of the median NWT resident, meaning that
adaptation costs are already disproportionate for them.
By 2022, up to 80% of buildings in some Northern Russia cities had already experienced damage. By 2050, the damage to residential infrastructure may reach
$15 billion, while total public infrastructure damages could amount to
132 billion. This includes oil and gas extraction facilities, of which 45% are believed to be at risk.
Toxic pollution
Graphical representation of leaks from various toxic hazards caused by the thaw of formerly stable permafrost.
For much of the 20th century, it was believed that permafrost would
"indefinitely" preserve anything buried there, and this made deep
permafrost areas popular locations for hazardous waste disposal. In
places like Canada's Prudhoe Bay
oil field, procedures were developed documenting the "appropriate" way
to inject waste beneath the permafrost. This means that as of 2023,
there are ~4500 industrial facilities in the Arctic permafrost areas
which either actively process or store hazardous chemicals.
Additionally, there are between 13,000 and 20,000 sites which have been
heavily contaminated, 70% of them in Russia, and their pollution is
currently trapped in the permafrost.
About a fifth of both the industrial and the polluted sites (1000
and 2200–4800) are expected to start thawing in the future even if the
warming does not increase from its 2020 levels. Only about 3% more sites
would start thawing between now and 2050 under the climate change
scenario consistent with the Paris Agreement goals, RCP2.6,
but by 2100, about 1100 more industrial facilities and 3500 to 5200
contaminated sites are expected to start thawing even then. Under the
very high emission scenario RCP8.5, 46% of industrial and contaminated
sites would start thawing by 2050, and virtually all of them would be
affected by the thaw by 2100.
Organochlorines and other persistent organic pollutants are of a particular concern, due to their potential to repeatedly reach local communities after their re-release through biomagnification in fish. At worst, future generations born in the Arctic would enter life with weakened immune systems due to pollutants accumulating across generations.
Distribution
of toxic substances currently located at various permafrost sites in
Alaska, by sector. The number of fish skeletons represents the toxicity
of each substance.
A notable example of pollution risks associated with permafrost was the 2020 Norilsk oil spill, caused by the collapse of diesel fuel storage tank at Norilsk-Taimyr Energy's thermal power plant No. 3. It spilled 6,000 tonnes of fuel into the land and 15,000 into the water, polluting Ambarnaya, Daldykan and many smaller rivers on Taimyr Peninsula, even reaching lake Pyasino, which is a crucial water source in the area. State of emergency at the federal level was declared. The event has been described as the second-largest oil spill in modern Russian history.
Another issue associated with permafrost thaw is the release of natural mercury
deposits. An estimated 800,000 tons of mercury are frozen in the
permafrost soil. According to observations, around 70% of it is simply
taken up by vegetation after the thaw. However, if the warming continues under RCP8.5, then permafrost emissions of mercury into the atmosphere
would match the current global emissions from all human activities by
2200. Mercury-rich soils also pose a much greater threat to humans and
the environment if they thaw near rivers. Under RCP8.5, enough mercury
will enter the Yukon River basin by 2050 to make its fish unsafe to eat under the EPA
guidelines. By 2100, mercury concentrations in the river will double. In contrast, even if mitigation is limited to RCP4.5 scenario, mercury
levels will increase by about 14% by 2100, and will not breach the EPA
guidelines even by 2300.
The impact of meltwater from Greenland goes beyond nutrient transport. For instance, meltwater also contains dissolved organic carbon,
which comes from the microbial activity on the ice sheet's surface,
and, to a lesser extent, from the remnants of ancient soil and
vegetation beneath the ice. There is about 0.5-27 billion tonnes of pure carbon underneath the entire ice sheet, and much less within it. This is much less than the 1400–1650 billion tonnes contained within the Arctic permafrost, or the annual anthropogenic emissions of around 40 billion tonnes of CO2.) Yet, the release of this carbon through meltwater can still act as a climate change feedback if it increases overall carbon dioxide emissions.
Impacts on indigenous peoples
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.
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. The reduction of sea ice will cause certain species populations to decline or even become extinct. Inuit communities are deeply reliant on seal hunting, which is dependent on sea ice flats, where seals are hunted.
Unsuspected changes in river and snow conditions will cause herds of animals, including reindeer, to change migration patterns, calving grounds, and forage availability. In good years, some communities are fully employed by the commercial harvest of certain animals. 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.
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. Many Arctic communities rely on frozen roadways to transport supplies and travel from area to area. The changing landscape and unpredictability of weather is creating new challenges in the Arctic. 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.
European Space Agency (ESA) launched CryoSat-2 on 8 April 2010. It provides satellite data on Arctic ice cover change rates.
International Arctic Buoy Program: deploys and maintains buoys that provide real-time position, pressure, temperature, and interpolated ice velocity data
'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.
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).
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. It is a follow-up report of the 2017 assessment, "Snow, Water, Ice and Permafrost in the Arctic" (SWIPA). The 2021 IPCC AR6 WG1 Technical Report confirmed that "[o]bserved and projected warming" were ""strongest in the Arctic". According to an 11 August 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". 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.
The 14 December 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.[218][47]
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".[218] The 2017 report said that the melting ice in the warming Arctic was unprecedented in the past 1500 years.[208][209] 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.[219]
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. The 2020 Siberian heatwave was "associated with extensive burning in the Arctic Circle".
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.
Argentina 
Australia 
Austria
Belarus
Belgium
Brazil 
Bulgaria
Canada
Chile 
China
Hong Kong and 
Macau
Colombia
Costa Rica
Cuba
Czech Republic
Denmark
Ecuador
Estonia
Finland
France 
Germany 
Greece
Guatemala
Hungary
Iceland
India
Italy
Japan 
Kazakhstan
Malaysia
Monaco
Mongolia
Netherlands
Suriname until its independence on 25 November 1975.
New Zealand 
North Korea
Norway 
Pakistan
Papua New Guinea
Peru
Poland
Portugal
Romania
Russia†
Soviet Union.
San Marino
Saudi Arabia
Slovakia
Slovenia
South Africa
South Korea
Spain (historical claim)
Sweden
Switzerland
Turkey
Ukraine
United Arab Emirates
United Kingdom
United States†
Uruguay 
Venezuela
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