Greenland ice sheet
Grønlands indlandsis
Sermersuaq
Greenland-ice sheet hg.jpg
TypeIce sheet
Coordinates76°42′N 41°12′W / 76.7°N 41.2°W / 76.7; -41.2Coordinates: 76°42′N 41°12′W / 76.7°N 41.2°W / 76.7; -41.2
Area1,710,000 km2 (660,000 sq mi)
Length2,400 km (1,500 mi)
Width1,100 km (680 mi)
Thickness2,000–3,000 m (6,600–9,800 ft)

The Greenland ice sheet (Danish: Grønlands indlandsis, Greenlandic: Sermersuaq) is a vast body of ice covering 1,710,000 square kilometres (660,000 sq mi), roughly near 80% of the surface of Greenland. It is sometimes referred to as an ice cap, or under the term inland ice, or its Danish equivalent, indlandsis. An acronym, GIS, is frequently used in the scientific literature.

It is the second largest ice body in the world, after the Antarctic ice sheet. The ice sheet is almost 2,900 kilometres (1,800 mi) long in a north–south direction, and its greatest width is 1,100 kilometres (680 mi) at a latitude of 77°N, near its northern margin. The average thickness is about 1.5 km (0.9 mi) and over 3 km (1.9 mi) at its thickest point.[1] In addition to the large ice sheet, smaller ice caps (such as Maniitsoq and Flade Isblink) as well as glaciers, cover between 76,000 and 100,000 square kilometres (29,000 and 39,000 sq mi) around the periphery.

The Greenland ice sheet is adversely affected by climate change. It is more vulnerable to climate change than the Antarctic ice sheet because of its position in the Arctic, where it is subject to the regional amplification of warming.[2][3] While only a small fraction of the ice sheet is expected to melt during the 21st century, it is believed that most or even all of the ice sheet is committed to melting under the present or likely near-future climate unless the recent warming is reversed, making it an example of a climate tipping point.[4][5] If the entire 2,850,000 cubic kilometres (684,000 cu mi) of ice were to melt, it would lead to a global sea level rise of 7.2 m (24 ft),[6] although this is expected to take millennia to fully play out.[5]

This narrated animation shows the accumulated change in the elevation of the Greenland ice sheet between 2003 and 2012.

General

The presence of ice-rafted sediments in deep-sea cores recovered from northwest Greenland, in the Fram Strait, and south of Greenland indicated the more or less continuous presence of either an ice sheet or ice sheets covering significant parts of Greenland for the last 18 million years. From about 11 million years ago to 10 million years ago, the Greenland Ice Sheet was greatly reduced in size. The Greenland Ice Sheet formed in the middle Miocene by coalescence of ice caps and glaciers. There was an intensification of glaciation during the Late Pliocene.[7] Ice sheet formed in connection to the uplift of the West Greenland and East Greenland uplands. The Western and Eastern Greenland mountains constitute passive continental margins that were uplifted in two phases, 10 and 5 million years ago, in the Miocene epoch.[A] Computer modelling shows that the uplift would have enabled glaciation by producing increased orographic precipitation and cooling the surface temperatures.[8] The oldest known ice in the current ice sheet is as much as 1,000,000 years old.[9] The ice cores also record human impact, such as lead from the Roman Empire.[10]

The weight of the ice has depressed the central area of Greenland; the bedrock surface is near sea level over most of the interior of Greenland, but mountains occur around the periphery, confining the sheet along its margins. If the ice suddenly disappeared, Greenland would most probably appear as an archipelago, at least until isostasy lifted the land surface above sea level once again. The ice surface reaches its greatest altitude on two north–south elongated domes, or ridges. The southern dome reaches almost 3,000 metres (10,000 ft) at latitudes 63°65°N; the northern dome reaches about 3,290 metres (10,800 ft) at about latitude 72°N (the fourth highest "summit" of Greenland). The crests of both domes are displaced east of the centre line of Greenland. The unconfined ice sheet does not reach the sea along a broad front anywhere in Greenland, so that no large ice shelves occur. The ice margin just reaches the sea, however, in a region of irregular topography in the area of Melville Bay southeast of Thule, as well as in Jokel Bay. Large outlet glaciers, which are restricted tongues of the ice sheet, move through bordering valleys around the periphery of Greenland to calve off into the ocean, producing the numerous icebergs that sometimes occur in North Atlantic shipping lanes. The best known of these outlet glaciers is Jakobshavn Glacier (Greenlandic: Sermeq Kujalleq), which, at its terminus, flows at speeds of 20 to 22 metres or 66 to 72 feet per day.

Glaciologist at work.
Glaciologist at work.

On the ice sheet, temperatures are generally substantially lower than elsewhere in Greenland, due to the local effects of ice-albedo feedback. The lowest mean annual temperatures, about −31 °C (−24 °F), occur on the north-central part of the north dome, and temperatures at the crest of the south dome are about −20 °C (−4 °F).[citation needed] On 22 December 1991, a temperature of −69.6 °C (−93.3 °F) was recorded at an automatic weather station near the topographic summit of the Greenland Ice Sheet, making it the lowest temperature ever recorded in the Northern Hemisphere. The record went unnoticed for more than 28 years and was finally recognized in 2020.[11]

The ice sheet as a record of past climates

NASA scientist Eric Rignot provides a narrated tour about Greenland's ice sheet.

See also: Greenland ice core project and Greenland Ice Sheet Project

The ice sheet, consisting of layers of compressed snow from more than 100,000 years, contains in its ice today's most valuable record of past climates. In the past decades, scientists have drilled ice cores up to 4 kilometres (2.5 mi) deep. Scientists have, using those ice cores, obtained information on (proxies for) temperature, ocean volume, precipitation, chemistry and gas composition of the lower atmosphere, volcanic eruptions, solar variability, sea-surface productivity, desert extent and forest fires. Subglacial sediment from ~1.4 km (0.87 mi) beneath the ice stored since 1966 indicates that Greenland was completely ice-free and vegetated at least once within the last million years. This was not expected and may show Greenland to be more fragile and sensitive to climate change than previously thought.[12]

Recent climate change

General considerations on rate of change

Arctic Temperature Trend 1981–2007
Arctic Temperature Trend 1981–2007

In the earlier decades, an area in the North Atlantic including southern Greenland was one of the only areas in the World showing cooling rather than warming,[13] and Greenland had shown more complex temperature trends than the other areas of the world. A 2006 paper on Greenland's temperature record showed that the warmest year on record was 1941 while the warmest decades were the 1930s and 1940s. The data used was from stations on the south and west coasts, most of which did not operate continuously the entire study period.[14] However, later and more complete data sets have established strong warming in the period 1979–2005 (consistent with the concurrently observed Arctic sea ice decline and its ice-albedo feedback)[15] As the Greenland Ice Sheet had experienced unprecedented melting since the detailed records began, and is likely to contribute substantially to sea level rise as well as to possible changes in ocean circulation in the future.

Albedo change in Greenland
Albedo change in Greenland

Several factors determine the net rate of growth or decline. These are:

  1. Accumulation and melting rates of snow in the central parts
  2. Melting of surface snow and ice which then flows into moulins, falls and flows to bedrock, lubricates the base of glaciers, and affects the speed of glacial motion. This flow is implicated in accelerating the speed of glaciers and thus the rate of glacial calving.
  3. Melting of ice along the sheet's margins (runoff) and basal hydrology,
  4. Iceberg calving into the sea from outlet glaciers also along the sheet's edges

The last time that the combination of these factors had resulted in a net mass gain was in 1996. As of 2022, Greenland ice sheet had been losing ice for 26 years in a row.[16]

The snow line is the dividing line between the area, above the snow line, where snow continues to accumulate during the summer, and the area below the snow line which experiences summer melting.[17] The melt zone, where summer warmth turns snow and ice into slush and melt ponds of meltwater, has been expanding at an accelerating rate in recent years. When the meltwater seeps down through cracks in the sheet, it accelerates the melting and, in some areas, allows the ice to slide more easily over the bedrock below, speeding its movement to the sea. Besides contributing to global sea level rise, the process adds freshwater to the ocean, which may disturb ocean circulation and thus regional climate.[2]

Satellite image of dark melt ponds.
Satellite image of dark melt ponds.

An examination of 32 outlet glaciers in southeast Greenland indicates that the acceleration is significant only for marine-terminating outlet glaciers—glaciers that calve into the ocean.[18] A 2008 study noted that the thinning of the ice sheet is most pronounced for marine-terminating outlet glaciers.[19] As a result of the above, all concluded that the only plausible sequence of events is that increased thinning of the terminus regions, of marine-terminating outlet glaciers, ungrounded the glacier tongues and subsequently allowed acceleration, retreat and further thinning.[20]

Two mechanisms have been utilized to explain the change in velocity of the Greenland Ice Sheets outlet glaciers. The first is the enhanced meltwater effect, which relies on additional surface melting, funneled through moulins reaching the glacier base and reducing the friction through a higher basal water pressure. (Not all meltwater is retained in the ice sheet and some moulins drain into the ocean, with varying rapidity.) This idea was observed to be the cause of a brief seasonal acceleration of up to 20% on Sermeq Kujalleq in 1998 and 1999 at Swiss Camp.[21] The acceleration lasted between two and three months and was less than 10% in 1996 and 1997 for example. They offered a conclusion that the "coupling between surface melting and ice-sheet flow provides a mechanism for rapid, large-scale, dynamic responses of ice sheets to climate warming". Examination of recent rapid supra-glacial lake drainage documented short term velocity changes due to such events, but they had little significance to the annual flow of the large outlet glaciers.[22]

Meltwater rivers may flow down into moulins
Meltwater rivers may flow down into moulins

The second mechanism is a force imbalance at the calving front due to thinning causing a substantial non-linear response. In this case an imbalance of forces at the calving front propagates up-glacier. Thinning causes the glacier to be more buoyant, reducing frictional back forces, as the glacier becomes more afloat at the calving front. The reduced friction due to greater buoyancy allows for an increase in velocity. This is akin to letting off the emergency brake a bit. The reduced resistive force at the calving front is then propagated up-glacier via longitudinal extension because of the backforce reduction.[23][24]If the enhanced meltwater effect is the key, then since meltwater is a seasonal input, velocity would have a seasonal signal and all glaciers would experience this effect. If the force imbalance effect is the key, then the velocity will propagate up-glacier, there will be no seasonal cycle, and the acceleration will be focused on calving glaciers.

Warmer temperatures in the region have brought increased precipitation to Greenland, and part of the lost mass has been offset by increased snowfall. However, there are only a small number of weather stations on the island, and though satellite data can examine the entire island, it has only been available since the early 1990s, making the study of trends difficult. It has been observed that there is more precipitation where it is warmer, up to 1.5 meters per year on the southeast flank, and less precipitation or none on the 25–80 percent (depending on the time of year) of the island that is cooler.[25] On the other hand, global warming is increasing growth of algae on the ice sheet. This darkens the ice causing it to absorb more sunlight and potentially increasing the rate of melting.[26]

Observations

2000s

Until 2007, rate of decrease in ice sheet height in cm per year.
Until 2007, rate of decrease in ice sheet height in cm per year.

The IPCC Third Assessment Report was published in 2001, and it estimated the accumulation to 520 ± 26 Gigatonnes of ice per year, runoff and bottom melting to 297±32 Gt/yr and 32±3 Gt/yr, respectively, and iceberg production to 235±33 Gt/yr. On balance, the IPCC estimates −44 ± 53 Gt/yr, which means that the ice sheet may currently be melting.[6] Data from 1996 to 2005 shows that the ice sheet is thinning even faster than supposed by IPCC. According to the study, in 1996 Greenland was losing about 96 km3 or 23.0 cu mi per year in volume from its ice sheet. In 2005, this had increased to about 220 km3 or 52.8 cu mi a year due to rapid thinning near its coasts,[27] while in 2006 it was estimated at 239 km3 (57.3 cu mi) per year.[28] It was estimated that in the year 2007 Greenland ice sheet melting was higher than ever, 592 km3 (142.0 cu mi). Also snowfall was unusually low, which led to unprecedented negative −65 km3 (−15.6 cu mi) Surface Mass Balance.[29] If iceberg calving has happened as an average, Greenland lost 294 Gt of its mass during 2007 (one km3 of ice weighs about 0.9 Gt).

By 2002, the area below the snow line was found to have increased by 16% since the beginning of detailed measurements in 1979. The area of melting in 2002 broke all previous records.[2] The number of glacial earthquakes at the Helheim Glacier and the northwest Greenland glaciers increased substantially between 1993 and 2005.[30] In 2006, estimated monthly changes in the mass of Greenland's ice sheet suggest that it is melting at a rate of about 239 cubic kilometers (57 cu mi) per year. A more recent study, based on reprocessed and improved data between 2003 and 2008, reports an average trend of 195 cubic kilometers (47 cu mi) per year.[31] These measurements came from the US space agency's GRACE (Gravity Recovery and Climate Experiment) satellite, launched in 2002, as reported by BBC.[28] Using data from two ground-observing satellites, ICESAT and ASTER, a study published in Geophysical Research Letters (September 2008) shows that nearly 75 percent of the loss of Greenland's ice can be traced back to small coastal glaciers.[18]

Satellite measurements of Greenland's ice cover from 1979 to 2009 reveals a trend of increased melting.
NASA's MODIS and QuikSCAT satellite data from 2007 were compared to confirm the precision of different melt observations.

Notable calving events had also been recorded in 2000s. For instance, Helheim Glacier in East Greenland had a stable terminus from the 1970s–2000. In 2001–2005 the glacier retreated 7 km (4.3 mi) and accelerated from 20 to 33 m or 70 to 110 ft/day, while thinning up to 130 meters (430 ft) in the terminus region. Kangerdlugssuaq Glacier, East Greenland had a stable terminus history from 1960 to 2002. The glacier velocity was 13 m or 43 ft/day in the 1990s. In 2004–2005 it accelerated to 36 m or 120 ft/day and thinned by up to 100 m (300 ft) in the lower reach of the glacier. On Sermeq Kujalleq the acceleration began at the calving front and spread up-glacier 20 km (12 mi) in 1997 and up to 55 km (34 mi) inland by 2003.[32] On Helheim the thinning and velocity propagated up-glacier from the calving front. In each case the major outlet glaciers accelerated by at least 50%, much larger than the impact noted due to summer meltwater increase. On each glacier the acceleration was not restricted to the summer, persisting through the winter when surface meltwater is absent.[citation needed]

Between 2000 and 2001, Northern Greenland's Petermann glacier lost 85 square kilometres (33 sq mi) of floating ice, and a 28-square-kilometre (11 sq mi) piece of Petermann suddenly broke away in 2008. Sermeq Kujalleq broke up by 2005, losing 93 square kilometres (36 sq mi) in a dramatic event credited by some NASA scientists with raising worldwide awareness of glacial response to global climate change.[33]

In 2007, the IPCC Fourth Assessment Report noted that most mass balance estimates indicate accelerating mass loss from Greenland during the 1990s up to 2005. Assessment of the data and techniques suggests a mass balance for the Greenland Ice Sheet ranging between growth of 25 Gt/yr and loss of 60 Gt/yr for 1961 to 2003, loss of 50 to 100 Gt/yr for 1993 to 2003 and loss at even higher rates between 2003 and 2005.[34]

Since 2010

Melting ice during July 2012, images created by NASA show the process in the summer
Melting ice during July 2012, images created by NASA show the process in the summer

A sheet of ice measuring 260 square kilometres (100 sq mi) broke off from the Petermann Glacier in northern Greenland in August 2010. Researchers from the Canadian Ice Service located the calving from NASA satellite images taken on August 5. The images showed that Petermann lost about one-quarter of its 70 km-long (43 mile) floating ice shelf.[35] Another large ice sheet twice the area of Manhattan, about 120 square kilometres (46 sq mi), broke away from that glacier in July 2012.[36]

In July 2012, melt zone extended to 97 percent of the ice sheet's cover.[37] Ice cores show that events such as this occur approximately every 150 years on average. The last time a melt this large happened was in 1889. This particular melt may be part of cyclical behavior; however, Lora Koenig, a Goddard glaciologist suggested that "...if we continue to observe melting events like this in upcoming years, it will be worrisome."[38][39][40] This was the first directly observed example of what came to be known as a "massive melting event": the ice core research most melting events before the 21st century were localized rather than widespread across the bulk of the Greenland ice sheet.[41] At the end of 2012, the analysis of gravity data from GRACE satellites indicated that the Greenland ice sheet lost approximately 2900 Gt (0.1% of its total mass) between March 2002 and September 2012. The mean mass loss rate for 2008–2012 was 367 Gt/year.[42]In 2015, Jakobshavn Glacier calved an iceberg about 4,600 feet (1,400 m) thick with an area of about 5 square miles (13 km2).[43]

Record ice loss during the 2019 melt season.[44]
Record ice loss during the 2019 melt season.[44]

A 2013 Nature study identified a contribution from the optically thin liquid-bearing clouds to the extent of ice melt during July 2012.[45] In 2016, another paper suggested that clouds in general enhance Greenland ice sheet's meltwater runoff by more than 30% due to decreased meltwater refreezing in the firn layer at night.[46]

In 2019, another mass melting event (covering more than 300,000 square miles) occurred in both June and July, due to cloud cover and high temperatures.[47][48] In August 2020, scientists reported that the Greenland ice sheet lost a record amount of 532 billion metric tons of ice during 2019, surpassing the old record of 464 billion metric tons in 2012 and returning to high melt rates, and provide explanations for the reduced ice loss in 2017 and 2018.[44][49]

A study published in 2020 estimated, by combining 26 individual estimates of mass balance derived by tracking changes in Greenland's ice sheet volume, speed and gravity as part of the Ice Sheet Mass Balance Inter-comparison Exercise, that the Greenland Ice Sheet had lost a total of 3,902 gigatons (Gt) of ice between 1992 and 2018. The rate of ice loss has increased over time from 26 ± 27 Gt/year between 1992 and 1997 to 244 ± 28 Gt/year between 2012 and 2017 with a peak mass loss rate of 275 ± 28 Gt/year during the period 2007 and 2012.[50]

In July 2021, a new surge of widespread melting began, covering 340,000 square miles of the ice sheet, and melting more than 8 billion tons of ice per day for several days.[51] In August 2021, as high temperatures continued over Greenland, with the melt extent at 337,000 square miles, rain fell for 13 hours at Greenland's Summit Station (at 10,551 feet elevation.)[52] Researchers had no rain gauges to measure the rainfall, because temperatures at the summit have risen above freezing only three times since 1989 and it had never rained there before.[47]

Future ice loss

Modelling results of the long-term sea-level rise under different warming scenarios from the IPCC Third Assessment Report.
Modelling results of the long-term sea-level rise under different warming scenarios from the IPCC Third Assessment Report.

Due to the enormous thickness of the central Greenland ice sheet, even the most extensive melting event can only affect a small fraction of it before the start of the freezing season. In scientific literature, they are described as "short-term variability": a 2020 paper found that the current models underestimate the extent and frequency of such events, meaning that the ice sheet decline in Greenland and Antarctica tracks worst-case scenarios of the IPCC Fifth Assessment Report's sea-level rise projections, [53][54][55][56] However, even those worst-case scenarios only involve a minor portion of the ice sheet during the 21st century: in 2021, the IPCC Sixth Assessment Report estimated that under SSP5-8.5, the scenario associated with the highest global warming, Greenland ice sheet melt would add around 13 cm to the global sea levels (with a likely range between 9 and 18cm and a very likely range (5-95% confidence level) between 5 and 23 cm), while the "moderate" SSP2-4.5 scenario adds 8 cm with a likely and very likely range of 4-13 cm and 1 cm to 18 cm, respectively. The scenario which largely fulfils the Paris Agreement goals, SSP1-2.6, adds around 6 cm and no more than 15 cm, with a small chance of the ice sheet gaining mass and thus reducing the sea levels by around 2 cm.[57] For comparison, Greenland Ice Sheet is estimated to have contributed about 0.68 mm per year between 2012 and 2017, which is already a significant acceleration from the 1990s, when it contributed 0.07 mm per year between 1992 and 1997. [58] This net contribution for the 2012–2016 period was also equivalent to 37% of sea level rise from land ice sources (excluding thermal expansion).[59]

However, while the ice sheet's massive size makes it insensitive to temperature changes in the short run, it also commits it to enormous changes down the line. Many scientists who study the ice losses in Greenland consider that an increase in temperature of two or three degrees Celsius would result in a complete melting of Greenland's ice.[43]If the entire 2,850,000 km3 (684,000 cu mi) of ice were to melt, global sea levels would rise 7.2 m (24 ft).[6] Recently, fears have grown that continued climate change will make the Greenland Ice Sheet cross a threshold where long-term melting of the ice sheet is inevitable.[60][61] Climate models project that local warming in Greenland will be 3 °C (5 °F) to 9 °C (16 °F) during this century. Ice sheet models project that such a warming would initiate the long-term melting of the ice sheet, leading to a complete melting of the ice sheet (over centuries), resulting in a global sea level rise of about 7 metres (23 ft).[2] Such a rise would inundate almost every major coastal city in the world. How fast the melt would eventually occur is a matter of discussion. According to the IPCC 2001 report,[6] such warming would, if kept from rising further after the 21st Century, result in 1 to 5 meter sea level rise over the next millennium due to Greenland ice sheet melting. Some scientists have cautioned that these rates of melting are overly optimistic as they assume a linear, rather than erratic, progression. James E. Hansen has argued that multiple positive feedbacks could lead to nonlinear ice sheet disintegration much faster than claimed by the IPCC. According to a 2007 paper, "we find no evidence of millennial lags between forcing and ice sheet response in paleoclimate data. An ice sheet response time of centuries seems probable, and we cannot rule out large changes on decadal time-scales once wide-scale surface melt is underway."[62]

These graphs indicate the switch to a dynamic state of sustained mass loss after the widespread retreat in 2000–2005.[63]
These graphs indicate the switch to a dynamic state of sustained mass loss after the widespread retreat in 2000–2005.[63]

In a 2013 study published in Nature, 133 researchers analyzed a Greenland ice core from the Eemian interglacial. They concluded that during this geological period, roughly 130,000–115,000 years ago, the GIS (Greenland Ice Sheet) was 8 degrees C warmer than today. This resulted in a thickness decrease of the northwest Greenland ice sheet by 400 ± 250 metres, reaching surface elevations 122,000 years ago of 130 ± 300 metres lower than at present.[64] A 2021 analysis of sub-glacial sediment at the bottom of a 1.4 km Greenland ice core finds that the Greenland ice sheet melted away at least once during the last million years, and therefore strongly suggests that its tipping point is below the 2.5 °C maximum positive temperature excursion over that period.[65][12]

On 13 August 2020, Communications Earth and Environment, a Nature Research journal published a study on "Dynamic ice loss from the Greenland Ice sheet driven by sustained glacier retreat". The situation was described as being past the "point of no return" and attributed to two factors, "increased surface meltwater runoff and ablation of marine-terminating outlet glaciers via calving and submarine melting, termed ice discharge."[63][66][67]

A 2022 assessment of tipping points in the climate system estimated that the Greenland ice sheet would most likely be committed to long-term disintegration around 1.5°C of global warming: in the best case, its disintegration would not be set in motion until 3°C, but in the worst case, it could already be inevitable unless the global warming is reduced below 0.8°C. At the same time, it also noted that the fastest plausible timeline for a disintegration is 1000 years after the tipping threshold is crossed, while it is far more likely to take place over 10,000 years; the longest possible estimate is 15,000 years. It had also estimated that due to the ice-albedo feedback, a total loss of the ice sheet would increase the global temperatures by 0.13°C, while the local temperatures would increase by between 0.5°C and 3.0°C. [4][5]

Meltwater run-off

See also: Cold blob (North Atlantic)

See also: Shutdown of thermohaline circulation

Meltwater creates rivers caused by cryoconite on July 21, 2012
Meltwater creates rivers caused by cryoconite on July 21, 2012

Meltwater around Greenland may transport nutrients and organic carbon to the ocean.[68][69] Measurements of the amount of iron in meltwater from the Greenland ice sheet show that extensive melting of the ice sheet might add an amount of this micronutrient to the Atlantic Ocean equivalent to that added by airborne dust.[70] However much of the particles and iron derived from glaciers around Greenland may be trapped within the extensive fjords that surround the island[71] and, unlike the HNLC Southern ocean where iron is an extensive limiting micronutrient,[72] biological production in the North Atlantic is subject only to very spatially and temporally limited periods of iron limitation.[73] Nonetheless, high productivity is observed in the immediate vicinity of major marine terminating glaciers around Greenland and this is attributed to meltwater inputs driving the upwelling of seawater rich in macronutrients.[74]

The United States built a secret nuclear powered base, called Camp Century, in the Greenland ice sheet.[75] 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.[76]

A study published in 2016, by researchers from the University of South Florida, Canada and the Netherlands, used GRACE satellite data to estimate freshwater flux from Greenland. They concluded that freshwater runoff is accelerating, and could eventually cause a disruption of AMOC in the future, which would affect Europe and North America.[77]

A 2018 international study found that the fertilizing effect of meltwater around Greenland is highly sensitive to the glacier grounding line depth it is released at. Retreat of Greenland's large marine-terminating glaciers inland will diminish the fertilizing effect of meltwater- even with further large increases in freshwater discharge volume.[78]

A 2015 study by climate scientists Michael Mann of Penn State and Stefan Rahmstorf from the Potsdam Institute for Climate Impact Research suggests that the observed cold blob in the North Atlantic during years of temperature records is a sign that the Atlantic Ocean's Meridional overturning circulation (AMOC) may be weakening. They published their findings, and concluded that the AMOC circulation shows exceptional slowdown in the last century, and that Greenland melt is a possible contributor.[79]

The cold blob visible on NASA's global mean temperatures for 2015, the warmest year on record up to 2015 (since 1880) – Colors indicate temperature evolution (NASA/NOAA; 20 January 2016).[80]
The cold blob visible on NASA's global mean temperatures for 2015, the warmest year on record up to 2015 (since 1880) – Colors indicate temperature evolution (NASA/NOAA; 20 January 2016).[80]

See also

Notes

  1. ^ The timing of the uplift of Greenland is known from the study of planation surfaces formed near sea-level. Greenland has two large planation surfaces: the older Upper Planation Surface and the younger Lower Planation Surface. The Upper Planation Surface has been uplifted 2000 to 3000 masl. since formation and the Lower Planation Surface has been uplifted 500 to 1000 masl.[8]

References

  1. ^ Greenland Ice Sheet.
  2. ^ a b c d Impacts of a Warming Arctic: Arctic Climate Impact Assessment, Cambridge University Press, 2004. [1] Archived 2006-11-19 at the Wayback Machine
  3. ^ Moon, Twila; Ahlstrøm, Andreas; Goelzer, Heiko; Lipscomb, William; Nowicki, Sophie (2018). "Rising Oceans Guaranteed: Arctic Land Ice Loss and Sea Level Rise". Current Climate Change Reports. 4 (3): 211–222. doi:10.1007/s40641-018-0107-0. ISSN 2198-6061. PMC 6428231. PMID 30956936.
  4. ^ a b 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). doi:10.1126/science.abn7950. ISSN 0036-8075.
  5. ^ a b c 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.
  6. ^ a b c d Climate Change 2001: The Scientific Basis. Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) [Houghton, J.T., Y. Ding, D.J. Griggs, M. Noguer, P.J. van der Linden, X. Dai, K. Maskell, and C.A. Johnson (eds.)]Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 881pp. [2] Archived 2007-12-16 at the Wayback Machine, "Climate Change 2001: The Scientific Basis". Archived from the original on 2006-02-10. Retrieved 2006-02-10., and [3].
  7. ^ Thiede, JC Jessen, P Knutz, A Kuijpers, N Mikkelsen, N Norgaard-Pedersen, and R Spielhagen (2011) Millions of Years of Greenland Ice Sheet History Recorded in Ocean Sediments. Polarforschung. 80(3):141–159.
  8. ^ a b Solgaard, Anne M.; Bonow, Johan M.; Langen, Peter L.; Japsen, Peter; Hvidberg, Christine (2013). "Mountain building and the initiation of the Greenland Ice Sheet". Palaeogeography, Palaeoclimatology, Palaeoecology. 392: 161–176. Bibcode:2013PPP...392..161S. doi:10.1016/j.palaeo.2013.09.019.
  9. ^ Yau, Audrey M.; Bender, Michael L.; Blunier, Thomas; Jouzel, Jean (2016). "Setting a chronology for the basal ice at Dye-3 and GRIP: Implications for the long-term stability of the Greenland Ice Sheet". Earth and Planetary Science Letters. 451: 1–9. Bibcode:2016E&PSL.451....1Y. doi:10.1016/j.epsl.2016.06.053.
  10. ^ McConnell, Joseph R.; Wilson, Andrew I.; Stohl, Andreas; Arienzo, Monica M.; Chellman, Nathan J.; Eckhardt, Sabine; Thompson, Elisabeth M.; Pollard, A. Mark; Steffensen, Jørgen Peder (2018-05-29). "Lead pollution recorded in Greenland ice indicates European emissions tracked plagues, wars, and imperial expansion during antiquity". Proceedings of the National Academy of Sciences. 115 (22): 5726–5731. Bibcode:2018PNAS..115.5726M. doi:10.1073/pnas.1721818115. PMC 5984509. PMID 29760088.
  11. ^ "WMO verifies -69.6°C Greenland temperature as Northern hemisphere record". World Meteorological Organization. September 22, 2020.
  12. ^ a b Christ, Andrew J.; Bierman, Paul R.; Schaefer, Joerg M.; Dahl-Jensen, Dorthe; Steffensen, Jørgen P.; Corbett, Lee B.; Peteet, Dorothy M.; Thomas, Elizabeth K.; Steig, Eric J.; Rittenour, Tammy M.; Tison, Jean-Louis; Blard, Pierre-Henri; Perdrial, Nicolas; Dethier, David P.; Lini, Andrea; Hidy, Alan J.; Caffee, Marc W.; Southon, John (30 March 2021). "A multimillion-year-old record of Greenland vegetation and glacial history preserved in sediment beneath 1.4 km of ice at Camp Century". Proceedings of the National Academy of Sciences. 118 (13): e2021442118. Bibcode:2021PNAS..11821442C. doi:10.1073/pnas.2021442118. ISSN 0027-8424. PMC 8020747. PMID 33723012.
  13. ^ see Arctic Climate Impact Assessment (2004) and IPCC Second Assessment Report, among others.
  14. ^ Vinther, B. M.; Andersen, K. K.; Jones, P. D.; Briffa, K. R.; Cappelen, J. (2006). "Extending Greenland temperature records into the late eighteenth century" (PDF). Journal of Geophysical Research. 111 (D11): D11105. Bibcode:2006JGRD..11111105V. doi:10.1029/2005JD006810.
  15. ^ IPCC, 2007. Trenberth, K.E., P.D. Jones, P. Ambenje, R. Bojariu, D. Easterling, A. Klein Tank, D. Parker, F. Rahimzadeh, J.A. Renwick, M. Rusticucci, B. Soden and P. Zhai, 2007: Observations: Surface and Atmospheric Climate Change. In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.[4] Archived 2017-10-23 at the Wayback Machine
  16. ^ Stendel, Martin; Mottram, Ruth (22 September 2022). "Guest post: How the Greenland ice sheet fared in 2022". Carbon Brief. Retrieved 2022-10-22.
  17. ^ Chris Mooney (August 29, 2022). "Greenland ice sheet set to raise sea levels by nearly a foot, study finds". The Washington Post. Retrieved August 29, 2022. As it thaws, scientists think the change will manifest itself at a location called the snow line. This is the dividing line between the high altitude, bright white parts of the ice sheet that accumulate snow and mass even during the summer, and the darker, lower elevation parts that melt and contribute water to the sea. This line moves every year, depending on how warm or cool the summer is, tracking how much of Greenland melts in a given period.
  18. ^ a b Howat, Ian M.; Smith, Ben E.; Joughin, Ian; Scambos, Ted A. (2008-09-09). "Rates of southeast Greenland ice volume loss from combined ICESat and ASTER observations". Geophysical Research Letters. 35 (17). Bibcode:2008GeoRL..3517505H. doi:10.1029/2008gl034496. ISSN 0094-8276. S2CID 3468378.
  19. ^ Sole, A.; Payne, T.; Bamber, J.; Nienow, P.; Krabill, W. (2008-12-16). "Testing hypotheses of the cause of peripheral thinning of the Greenland Ice Sheet: is land-terminating ice thinning at anomalously high rates?". The Cryosphere. 2 (2): 205–218. Bibcode:2008TCry....2..205S. doi:10.5194/tc-2-205-2008. ISSN 1994-0424. S2CID 16539240.
  20. ^ Luckman, Adrian; Murray, Tavi; de Lange, Remko; Hanna, Edward (2006). "Rapid and synchronous ice-dynamic changes in East Greenland". Geophysical Research Letters. 33 (3). Bibcode:2006GeoRL..33.3503L. doi:10.1029/2005gl025428. ISSN 0094-8276. S2CID 55517773.
  21. ^ Zwally, H. Jay; Abdalati, Waleed; Herring, Tom; Larson, Kristine; Saba, Jack; Steffen, Konrad (2002-07-12). "Surface Melt-Induced Acceleration of Greenland Ice-Sheet Flow". Science. 297 (5579): 218–222. Bibcode:2002Sci...297..218Z. doi:10.1126/science.1072708. PMID 12052902. S2CID 37381126.
  22. ^ Das, Sarah B.; Joughin, Ian; Behn, Mark D.; Howat, Ian M.; King, Matt A.; Lizarralde, Dan; Bhatia, Maya P. (2008-05-09). "Fracture Propagation to the Base of the Greenland Ice Sheet During Supraglacial Lake Drainage". Science. 320 (5877): 778–781. Bibcode:2008Sci...320..778D. doi:10.1126/science.1153360. hdl:1912/2506. PMID 18420900. S2CID 41582882.
  23. ^ Thomas, Robert H. (2004). "Force-perturbation analysis of recent thinning and acceleration of Jakobshavn Isbræ, Greenland". Journal of Glaciology. 50 (168): 57–66. Bibcode:2004JGlac..50...57T. doi:10.3189/172756504781830321. ISSN 0022-1430. S2CID 128911716.
  24. ^ Thomas, R. H. Abdalati W; Frederick, E; Krabill, WB; Manizade, S; Steffen, K (2003). "Investigation of surface melting and dynamic thinning on Jakobshavn Isbrae, Greenland". Journal of Glaciology. 49 (165): 231–239. Bibcode:2003JGlac..49..231T. doi:10.3189/172756503781830764.
  25. ^ "Modelling Precipitation over ice sheets: an assessment using Greenland", Gerard H. Roe, University of Washington, [5]
  26. ^ Sea level fears as Greenland darkens BBC
  27. ^ "Greenland Ice Loss Doubles in Past Decade, Raising Sea Level Faster". Jet Propulsion Laboratory News release, Thursday, 16 February 2006. "JPL.NASA.GOV: Greenland Ice Loss Doubles in Past Decade, Raising Sea Level Faster". Jet Propulsion Laboratory. Archived from the original on 2006-10-03. Retrieved 2006-02-22.
  28. ^ a b "BBC NEWS – Science/Nature – Greenland melt 'speeding up'". bbc.co.uk. 2006-08-11.
  29. ^ "cosis.net". site2.e-public.net.
  30. ^ Nettles, Meredith; Ekström, Göran (2010-04-01). "Glacial Earthquakes in Greenland and Antarctica". Annual Review of Earth and Planetary Sciences. 38 (1): 467–491. Bibcode:2010AREPS..38..467N. doi:10.1146/annurev-earth-040809-152414. ISSN 0084-6597.
  31. ^ Wouters, B.; Chambers, D.; Schrama, E. J. O. (2008-10-16). "GRACE observes small-scale mass loss in Greenland". Geophysical Research Letters. 35 (20). Bibcode:2008GeoRL..3520501W. doi:10.1029/2008gl034816. ISSN 0094-8276. S2CID 17155157.
  32. ^ Joughin, I; Abdalati, W; Fahnestock, M (December 2004). "Large fluctuations in speed on Greenland's Jakobshavn Isbræ glacier". Nature. 432 (7017): 608–610. Bibcode:2004Natur.432..608J. doi:10.1038/nature03130. PMID 15577906. S2CID 4406447.
  33. ^ "Images Show Breakup of Two of Greenland's Largest Glaciers, Predict Disintegration in Near Future". NASA Earth Observatory. August 20, 2008. Archived from the original on August 31, 2008. Retrieved 2008-08-31.
  34. ^ Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Chapter 4 Observations: Changes in Snow, Ice and Frozen Ground.IPCC, 2007. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 996 pp. [6]
  35. ^ "Huge ice island breaks from Greenland glacier". BBC News. 2010-08-07.
  36. ^ Iceberg breaks off from Greenland's Petermann Glacier 19 July 2012
  37. ^ "Greenland enters melt mode". Science News. 2013-09-23.
  38. ^ Wall, Tim (2017-05-10). "Greenland Hits 97 Percent Meltdown in July". Discovery News.
  39. ^ "NASA Made Up 150 Year Melt Cycle". Daily Kos.
  40. ^ Meese, D. A.; Gow, A. J.; Grootes, P.; Stuiver, M.; Mayewski, P. A.; Zielinski, G. A.; Ram, M.; Taylor, K. C.; Waddington, E. D. (1994). "The Accumulation Record from the GISP2 Core as an Indicator of Climate Change Throughout the Holocene". Science. 266 (5191): 1680–1682. Bibcode:1994Sci...266.1680M. doi:10.1126/science.266.5191.1680. PMID 17775628. S2CID 12059819.
  41. ^ Barnes, Adam (August 9, 2021). "'Massive melting event' torpedoes billions of tons of ice the whole world depends on". The Hill. Retrieved August 24, 2021. Ice cores show that these widespread melt events were really rare prior to the 21st century, but since then, we have had several melt seasons.
  42. ^ "Arctic Report Card: Update for 2012; Greenland Ice Sheet" (PDF). 2012.
  43. ^ a b "The Secrets in Greenland's Ice Sheet". The New York Times. 2015.
  44. ^ a b "Record melt: Greenland lost 586 billion tons of ice in 2019". phys.org. Retrieved 6 September 2020.
  45. ^ Bennartz, R.; Shupe, M. D.; Turner, D. D.; Walden, V. P.; Steffen, K.; Cox, C. J.; Kulie, M. S.; Miller, N. B.; Pettersen, C. (2013). "July 2012 Greenland melt extent enhanced by low-level liquid clouds". Nature. 496 (7443): 83–86. Bibcode:2013Natur.496...83B. doi:10.1038/nature12002. PMID 23552947. S2CID 4382849.
  46. ^ Van Tricht, K.; Lhermitte, S.; Lenaerts, J. T. M.; Gorodetskaya, I. V.; L’Ecuyer, T. S.; Noël, B.; van den Broeke, M. R.; Turner, D. D.; van Lipzig, N. P. M. (2016-01-12). "Clouds enhance Greenland ice sheet meltwater runoff". Nature Communications. 7: 10266. Bibcode:2016NatCo...710266V. doi:10.1038/ncomms10266. PMC 4729937. PMID 26756470.
  47. ^ a b Patel, Kasha (August 19, 2021). "Rain falls at the summit of Greenland Ice Sheet for first time on record". Washington Post. Retrieved August 24, 2021. Rain fell on and off for 13 hours at the station, but staff are not certain exactly how much rain fell...there are no rain gauges at the summit because no one expected it to rain at this altitude.
  48. ^ Turner, Ben (August 2, 2021). "'Massive melting event' strikes Greenland after record heat wave". LiveScience.com. Retrieved August 24, 2021. High temperatures on July 28 caused the third-largest single-day loss of ice in Greenland since 1950; the second and first biggest single-day losses occurred in 2012 and 2019. Greenland’s yearly ice loss began in 1990. In recent years it has accelerated to roughly four times the levels before 2000.
  49. ^ Sasgen, Ingo; Wouters, Bert; Gardner, Alex S.; King, Michalea D.; Tedesco, Marco; Landerer, Felix W.; Dahle, Christoph; Save, Himanshu; Fettweis, Xavier (20 August 2020). "Return to rapid ice loss in Greenland and record loss in 2019 detected by the GRACE-FO satellites". Communications Earth & Environment. 1 (1): 8. Bibcode:2020ComEE...1....8S. doi:10.1038/s43247-020-0010-1. ISSN 2662-4435. S2CID 221200001.
    CC BY icon.svg
    Text and images are available under a Creative Commons Attribution 4.0 International License.
  50. ^ Shepherd, Andrew; Ivins, Erik; Rignot, Eric; Smith, Ben; van den Broeke, Michiel; Velicogna, Isabella; Whitehouse, Pippa; Briggs, Kate; Joughin, Ian; Krinner, Gerhard; Nowicki, Sophie (2020-03-12). "Mass balance of the Greenland Ice Sheet from 1992 to 2018". Nature. 579 (7798): 233–239. doi:10.1038/s41586-019-1855-2. ISSN 1476-4687. PMID 31822019. S2CID 219146922. Archived from the original on 27 March 2020. Alt URL
  51. ^ Milman, Oliver (July 30, 2021). "Greenland: enough ice melted on single day to cover Florida in two inches of water". The Guardian. Retrieved August 24, 2021. Greenland’s vast ice sheet is undergoing a surge in melting...The deluge of melting has reached deep into Greenland’s enormous icy interior, with data from the Danish government showing that the ice sheet lost 8.5bn tons of surface mass on Tuesday alone.
  52. ^ Carrington, Damian (August 20, 2021). "Rain falls on peak of Greenland ice cap for first time on record". The Guardian. Retrieved August 24, 2021. Rain has fallen on the summit of Greenland’s huge ice cap for the first time on record. Temperatures are normally well below freezing on the 3,216-metre (10,551ft) peak...Scientists at the US National Science Foundation’s summit station saw rain falling throughout 14 August but had no gauges to measure the fall because the precipitation was so unexpected.
  53. ^ "Sea level rise from ice sheets track worst-case climate change scenario". phys.org. Retrieved 8 September 2020.
  54. ^ "Earth's ice sheets tracking worst-case climate scenarios". The Japan Times. 1 September 2020. Retrieved 8 September 2020.
  55. ^ "Ice sheet melt on track with 'worst-case climate scenario'". www.esa.int. Retrieved 8 September 2020.
  56. ^ Slater, Thomas; Hogg, Anna E.; Mottram, Ruth (31 August 2020). "Ice-sheet losses track high-end sea-level rise projections". Nature Climate Change. 10 (10): 879–881. Bibcode:2020NatCC..10..879S. doi:10.1038/s41558-020-0893-y. ISSN 1758-6798. S2CID 221381924. Archived from the original on 2 September 2020. Retrieved 8 September 2020. Alt URL
  57. ^ 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 9: Ocean, Cryosphere and Sea Level Change" (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: 1260.
  58. ^ Shepherd, Andrew; Ivins, Erik; Rignot, Eric; Smith, Ben; van den Broeke, Michiel; Velicogna, Isabella; Whitehouse, Pippa; Briggs, Kate; Joughin, Ian; Krinner, Gerhard; Nowicki, Sophie (2020-03-12). "Mass balance of the Greenland Ice Sheet from 1992 to 2018". Nature. 579 (7798): 233–239. doi:10.1038/s41586-019-1855-2. hdl:2268/242139. ISSN 1476-4687. PMID 31822019. S2CID 219146922.
  59. ^ Bamber, Jonathan L; Westaway, Richard M; Marzeion, Ben; Wouters, Bert (1 June 2018). "The land ice contribution to sea level during the satellite era". Environmental Research Letters. 13 (6): 063008. Bibcode:2018ERL....13f3008B. doi:10.1088/1748-9326/aac2f0.
  60. ^ "Greenland ice loss is at 'worse-case scenario' levels, study finds". UCI News. 2019-12-19. Retrieved 2020-01-04.
  61. ^ Irvalı, Nil; Galaasen, Eirik V.; Ninnemann, Ulysses S.; Rosenthal, Yair; Born, Andreas; Kleiven, Helga (Kikki) F. (2019-12-18). "A low climate threshold for south Greenland Ice Sheet demise during the Late Pleistocene". Proceedings of the National Academy of Sciences. 117 (1): 190–195. doi:10.1073/pnas.1911902116. ISSN 0027-8424. PMC 6955352. PMID 31871153.
  62. ^ Hansen, James; Sato, Makiko; Kharecha, Pushker; Russell, Gary; Lea, David W.; Siddall, Mark (2007). "Climate change and trace gases". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences. 365 (1856): 1925–1954. Bibcode:2007RSPTA.365.1925H. doi:10.1098/rsta.2007.2052. PMID 17513270. S2CID 8785953.
  63. ^ a b "Warming Greenland ice sheet passes point of no return". EurekAlert!. 13 August 2020. Retrieved 15 August 2020.
  64. ^ NEEM community members; Dahl-Jensen, D.; Albert, M. R.; Aldahan, A.; Azuma, N.; Balslev-Clausen, D.; Baumgartner, M.; Berggren, A. -M.; Bigler, M.; Binder, T.; Blunier, T.; Bourgeois, J. C.; Brook, E. J.; Buchardt, S. L.; Buizert, C.; Capron, E.; Chappellaz, J.; Chung, J.; Clausen, H. B.; Cvijanovic, I.; Davies, S. M.; Ditlevsen, P.; Eicher, O.; Fischer, H.; Fisher, D. A.; Fleet, L. G.; Gfeller, G.; Gkinis, V.; Gogineni, S.; et al. (January 24, 2013). "Eemian interglacial reconstructed from a Greenland folded ice core" (PDF). Nature. 493 (7433): 489–494. Bibcode:2013Natur.493..489N. doi:10.1038/nature11789. PMID 23344358. S2CID 4420908.
  65. ^ Garric, Audrey (15 March 2021). "La calotte glaciaire du Groenland a déjà fondu au moins une fois au cours du dernier million d'années". Le Monde.
  66. ^ "Warming Greenland ice sheet passes point of no return". Ohio State University. 13 August 2020. Retrieved 15 August 2020.
  67. ^ King, Michalea D.; Howat, Ian M.; Candela, Salvatore G.; Noh, Myoung J.; Jeong, Seongsu; Noël, Brice P. Y.; van den Broeke, Michiel R.; Wouters, Bert; Negrete, Adelaide (13 August 2020). "Dynamic ice loss from the Greenland Ice Sheet driven by sustained glacier retreat". Communications Earth & Environment. 1 (1): 1–7. doi:10.1038/s43247-020-0001-2. ISSN 2662-4435.
    CC BY icon.svg
    Text and images are available under a Creative Commons Attribution 4.0 International License.
  68. ^ Statham, Peter J.; Skidmore, Mark; Tranter, Martyn (2008-09-01). "Inputs of glacially derived dissolved and colloidal iron to the coastal ocean and implications for primary productivity". Global Biogeochemical Cycles. 22 (3): GB3013. Bibcode:2008GBioC..22.3013S. doi:10.1029/2007GB003106. ISSN 1944-9224.
  69. ^ Bhatia, Maya P.; Das, Sarah B.; Longnecker, Krista; Charette, Matthew A.; Kujawinski, Elizabeth B. (2010-07-01). "Molecular characterization of dissolved organic matter associated with the Greenland ice sheet". Geochimica et Cosmochimica Acta. 74 (13): 3768–3784. Bibcode:2010GeCoA..74.3768B. doi:10.1016/j.gca.2010.03.035. ISSN 0016-7037.
  70. ^ Bhatia, Maya P.; Kujawinski, Elizabeth B.; Das, Sarah B.; Breier, Crystaline F.; Henderson, Paul B.; Charette, Matthew A. (2013). "Greenland meltwater as a significant and potentially bioavailable source of iron to the ocean". Nature Geoscience. 6 (4): 274–278. Bibcode:2013NatGe...6..274B. doi:10.1038/ngeo1746. ISSN 1752-0894.
  71. ^ Hopwood, Mark James; Connelly, Douglas Patrick; Arendt, Kristine Engel; Juul-Pedersen, Thomas; Stinchcombe, Mark; Meire, Lorenz; Esposito, Mario; Krishna, Ram (2016-01-01). "Seasonal changes in Fe along a glaciated Greenlandic fjord". Frontiers in Earth Science. 4: 15. Bibcode:2016FrEaS...4...15H. doi:10.3389/feart.2016.00015.
  72. ^ Martin, John H.; Fitzwater, Steve E.; Gordon, R. Michael (1990-03-01). "Iron deficiency limits phytoplankton growth in Antarctic waters". Global Biogeochemical Cycles. 4 (1): 5–12. Bibcode:1990GBioC...4....5M. doi:10.1029/GB004i001p00005. ISSN 1944-9224.
  73. ^ Nielsdóttir, Maria C.; Moore, Christopher Mark; Sanders, Richard; Hinz, Daria J.; Achterberg, Eric P. (2009-09-01). "Iron limitation of the postbloom phytoplankton communities in the Iceland Basin" (PDF). Global Biogeochemical Cycles. 23 (3): GB3001. Bibcode:2009GBioC..23.3001N. doi:10.1029/2008GB003410. ISSN 1944-9224. S2CID 129736136.
  74. ^ Arendt, Kristine Engel; Nielsen, Torkel Gissel; Rysgaard, Sren; Tnnesson, Kajsa (2010-02-22). "Differences in plankton community structure along the Godthåbsfjord, from the Greenland Ice Sheet to offshore waters". Marine Ecology Progress Series. 401: 49–62. Bibcode:2010MEPS..401...49E. doi:10.3354/meps08368.
  75. ^ "A Top-Secret US Military Base Will Melt Out of the Greenland Ice Sheet". VICE Magazine. 9 March 2019.
  76. ^ Laskow, Sarah (2018-02-27). "America's Secret Ice Base Won't Stay Frozen Forever". Wired. ISSN 1059-1028.
  77. ^ "Melting Greenland ice sheet may affect global ocean circulation, future climate". Phys.org. 2016.
  78. ^ Hopwood, M. J.; Carroll, D.; Browning, T. J.; Meire, L.; Mortensen, J.; Krisch, S.; Achterberg, E. P. (14 August 2018). "Non-linear response of summertime marine productivity to increased meltwater discharge around Greenland". Nature Communications. 9 (1): 3256. Bibcode:2018NatCo...9.3256H. doi:10.1038/s41467-018-05488-8. PMC 6092443. PMID 30108210.
  79. ^ Stefan Rahmstorf, Jason E. Box, Georg Feulner, Michael E. Mann, Alexander Robinson, Scott Rutherford & Erik J. Schaffernicht (May 2015). "Exceptional twentieth-century slowdown in Atlantic Ocean overturning circulation" (PDF). Nature. 5 (5): 475–480. Bibcode:2015NatCC...5..475R. doi:10.1038/nclimate2554.((cite journal)): CS1 maint: uses authors parameter (link)
  80. ^ Brown, Dwayne; Cabbage, Michael; McCarthy, Leslie; Norton, Karen (20 January 2016). "NASA, NOAA Analyses Reveal Record-Shattering Global Warm Temperatures in 2015". NASA. Retrieved 21 January 2016.