Clathrate hydrates have been identified as a possible agent for abrupt changes.

An abrupt climate change occurs when the climate system is forced to transition at a rate that is determined by the climate system energy-balance. The transition rate is more rapid than the rate of change of the external forcing,[1] though it may include sudden forcing events such as meteorite impacts.[2] Abrupt climate change therefore is a variation beyond the variability of a climate. Past events include the end of the Carboniferous Rainforest Collapse,[3] Younger Dryas,[4] Dansgaard–Oeschger events, Heinrich events and possibly also the Paleocene–Eocene Thermal Maximum.[5] The term is also used within the context of climate change to describe sudden climate change that is detectable over the time-scale of a human lifetime, possibly as the result of feedback loops within the climate system[6] or tipping points.

Timescales of events described as abrupt may vary dramatically. For example, the Paleocene–Eocene Thermal Maximum may have initiated anywhere between a few decades and several thousand years. In comparison, Earth System's models project that under ongoing greenhouse gas emissions as early as 2047, the Earth's near surface temperature could depart from the range of variability in the last 150 years.[7]

Definitions

Abrupt climate change can be defined in terms of physics or in terms of impacts: "In terms of physics, it is a transition of the climate system into a different mode on a time scale that is faster than the responsible forcing. In terms of impacts, an abrupt change is one that takes place so rapidly and unexpectedly that human or natural systems have difficulty adapting to it. These definitions are complementary: the former gives some insight into how abrupt climate change comes about; the latter explains why there is so much research devoted to it."[8]

Timescales

Timescales of events described as abrupt may vary dramatically. Changes recorded in the climate of Greenland at the end of the Younger Dryas, as measured by ice-cores, imply a sudden warming of +10 °C (+18 °F) within a timescale of a few years.[9] Other abrupt changes are the +4 °C (+7.2 °F) on Greenland 11,270 years ago[10] or the abrupt +6 °C (11 °F) warming 22,000 years ago on Antarctica.[11]

By contrast, the Paleocene–Eocene Thermal Maximum may have initiated anywhere between a few decades and several thousand years. Finally, Earth System's models project that under ongoing greenhouse gas emissions as early as 2047, the Earth's near surface temperature could depart from the range of variability in the last 150 years.[7]

General

Possible tipping elements in the climate system include regional effects of climate change, some of which had abrupt onset and may therefore be regarded as abrupt climate change.[12] Scientists have stated, "Our synthesis of present knowledge suggests that a variety of tipping elements could reach their critical point within this century under anthropogenic climate change".[12]

It has been postulated that teleconnections – oceanic and atmospheric processes on different timescales – connect both hemispheres during abrupt climate change.[13]

A 2013 report from the U.S. National Research Council called for attention to the abrupt impacts of climate change, stating that even steady, gradual change in the physical climate system can have abrupt impacts elsewhere, such as in human infrastructure and ecosystems if critical thresholds are crossed. The report emphasizes the need for an early warning system that could help society better anticipate sudden changes and emerging impacts.[14]

A characteristic of the abrupt climate change impacts is that they occur at a rate that is faster than anticipated. This element makes ecosystems that are immobile and limited in their capacity to respond to abrupt changes, such as forestry ecosystems, particularly vulnerable.[15]

The probability of abrupt change for some climate related feedbacks may be low.[16][17] Factors that may increase the probability of abrupt climate change include higher magnitudes of global warming, warming that occurs more rapidly and warming that is sustained over longer time periods.[17]

Climate models

Main article: Climate model

Climate models are currently[when?] unable to predict abrupt climate change events, or most of the past abrupt climate shifts.[18] A potential abrupt feedback due to thermokarst lake formations in the Arctic, in response to thawing permafrost soils, releasing additional greenhouse gas methane, is currently not accounted for in climate models.[19]

Effects

A summary of the path of the thermohaline circulation. Blue paths represent deep-water currents, and red paths represent surface currents.
The Permian–Triassic extinction event, labelled "P–Tr" here, is the most significant extinction event in this plot for marine genera.

In the past, abrupt climate change has likely caused wide-ranging and severe effects as follows:

Tipping points in the climate system

Possible tipping elements in the climate system

In climate science, a tipping point is a critical threshold that, when crossed, leads to large, accelerating and often irreversible changes in the climate system.[29] If tipping points are crossed, they are likely to have severe impacts on human society and may accelerate global warming.[30][31] Tipping behavior is found across the climate system, for example in ice sheets, mountain glaciers, circulation patterns in the ocean, in ecosystems, and the atmosphere.[31] Examples of tipping points include thawing permafrost, which will release methane, a powerful greenhouse gas, or melting ice sheets and glaciers reducing Earth's albedo, which would warm the planet faster.

Tipping points are often, but not necessarily, abrupt. For example, with average global warming somewhere between 0.8 °C (1.4 °F) and 3 °C (5.4 °F), the Greenland ice sheet passes a tipping point and is doomed, but its melt would take place over millennia.[32][33] Tipping points are possible at today's global warming of just over 1 °C (1.8 °F) above preindustrial times, and highly probable above 2 °C (3.6 °F) of global warming.[31] It is possible that some tipping points are close to being crossed or have already been crossed, like those of the West Antarctic and Greenland ice sheets, the Amazon rainforest and warm-water coral reefs.[34] A danger is that if the tipping point in one system is crossed, this could cause a cascade of other tipping points, leading to severe, potentially catastrophic,[35] impacts.[36]

The geological record shows many abrupt changes that suggest tipping points may have been crossed in pre-historic times.[37]

Past events

The Younger Dryas period of abrupt climate change is named after the alpine flower, Dryas.

Several periods of abrupt climate change have been identified in the paleoclimatic record. Notable examples include:

There are also abrupt climate changes associated with the catastrophic draining of glacial lakes. One example of this is the 8.2-kiloyear event, which is associated with the draining of Glacial Lake Agassiz.[44] Another example is the Antarctic Cold Reversal, c. 14,500 years before present (BP), which is believed to have been caused by a meltwater pulse probably from either the Antarctic ice sheet[45] or the Laurentide Ice Sheet.[46] These rapid meltwater release events have been hypothesized as a cause for Dansgaard–Oeschger cycles,[47]

A 2017 study concluded that similar conditions to today's Antarctic ozone hole (atmospheric circulation and hydroclimate changes), ~17,700 years ago, when stratospheric ozone depletion contributed to abrupt accelerated Southern Hemisphere deglaciation. The event coincidentally happened with an estimated 192-year series of massive volcanic eruptions, attributed to Mount Takahe in West Antarctica.[48]

Possible precursors

Most abrupt climate shifts are likely due to sudden circulation shifts, analogous to a flood cutting a new river channel. The best-known examples are the several dozen shutdowns of the North Atlantic Ocean's Meridional Overturning Circulation during the last ice age, affecting climate worldwide.[49]

Climate feedback effects

The dark ocean surface reflects only 6 percent of incoming solar radiation; sea ice reflects 50 to 70 percent.[53]

See also: Climate change feedback and Tipping points in the climate system

One source of abrupt climate change effects is a feedback process, in which a warming event causes a change that adds to further warming.[54] The same can apply to cooling. Examples of such feedback processes are:

Volcanism

Isostatic rebound in response to glacier retreat (unloading) and increased local salinity have been attributed to increased volcanic activity at the onset of the abrupt Bølling–Allerød warming. They are associated with the interval of intense volcanic activity, hinting at an interaction between climate and volcanism: enhanced short-term melting of glaciers, possibly via albedo changes from particle fallout on glacier surfaces.[57]

See also

References

  1. ^ Harunur Rashid; Leonid Polyak; Ellen Mosley-Thompson (2011). Abrupt climate change: mechanisms, patterns, and impacts. American Geophysical Union. ISBN 9780875904849.
  2. ^ Committee on Abrupt Climate Change, National Research Council. (2002). "Definition of Abrupt Climate Change". Abrupt climate change : inevitable surprises. Washington, D.C.: National Academy Press. doi:10.17226/10136. ISBN 978-0-309-07434-6.
  3. ^ a b c Sahney, S.; Benton, M.J.; Falcon-Lang, H.J. (2010). "Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euramerica". Geology. 38 (12): 1079–1082. Bibcode:2010Geo....38.1079S. doi:10.1130/G31182.1.
  4. ^ Broecker, W. S. (May 2006). "Geology. Was the Younger Dryas triggered by a flood?". Science. 312 (5777): 1146–1148. doi:10.1126/science.1123253. ISSN 0036-8075. PMID 16728622. S2CID 39544213.
  5. ^ National Research Council (2002). Abrupt climate change : inevitable surprises. Washington, D.C.: National Academy Press. p. 108. ISBN 0-309-07434-7.
  6. ^ Rial, J. A.; Pielke Sr., R. A.; Beniston, M.; Claussen, M.; Canadell, J.; Cox, P.; Held, H.; De Noblet-Ducoudré, N.; Prinn, R.; Reynolds, J. F.; Salas, J. D. (2004). "Nonlinearities, Feedbacks and Critical Thresholds within the Earth's Climate System" (PDF). Climatic Change. 65: 11–00. doi:10.1023/B:CLIM.0000037493.89489.3f. hdl:11858/00-001M-0000-0013-A8E8-0. S2CID 14173232. Archived from the original (PDF) on 9 March 2013.
  7. ^ a b Mora, C (2013). "The projected timing of climate departure from recent variability". Nature. 502 (7470): 183–187. Bibcode:2013Natur.502..183M. doi:10.1038/nature12540. PMID 24108050. S2CID 4471413.
  8. ^ "1: What defines "abrupt" climate change?". LAMONT-DOHERTY EARTH OBSERVATORY. Retrieved 8 July 2021.
  9. ^ Grachev, A.M.; Severinghaus, J.P. (2005). "A revised +10±4 °C magnitude of the abrupt change in Greenland temperature at the Younger Dryas termination using published GISP2 gas isotope data and air thermal diffusion constants". Quaternary Science Reviews. 24 (5–6): 513–9. Bibcode:2005QSRv...24..513G. doi:10.1016/j.quascirev.2004.10.016.
  10. ^ Kobashi, T.; Severinghaus, J.P.; Barnola, J. (30 April 2008). "4 ± 1.5 °C abrupt warming 11,270 yr ago identified from trapped air in Greenland ice". Earth and Planetary Science Letters. 268 (3–4): 397–407. Bibcode:2008E&PSL.268..397K. doi:10.1016/j.epsl.2008.01.032.
  11. ^ Taylor, K.C.; White, J; Severinghaus, J; Brook, E; Mayewski, P; Alley, R; Steig, E; Spencer, M; Meyerson, E; Meese, D; Lamorey, G; Grachev, A; Gow, A; Barnett, B (January 2004). "Abrupt climate change around 22 ka on the Siple Coast of Antarctica". Quaternary Science Reviews. 23 (1–2): 7–15. Bibcode:2004QSRv...23....7T. doi:10.1016/j.quascirev.2003.09.004.
  12. ^ a b Lenton, T. M.; Held, H.; Kriegler, E.; Hall, J. W.; Lucht, W.; Rahmstorf, S.; Schellnhuber, H. J. (2008). "Inaugural Article: Tipping elements in the Earth's climate system". Proceedings of the National Academy of Sciences. 105 (6): 1786–1793. Bibcode:2008PNAS..105.1786L. doi:10.1073/pnas.0705414105. PMC 2538841. PMID 18258748.
  13. ^ Markle; et al. (2016). "Global atmospheric teleconnections during Dansgaard–Oeschger events". Nature Geoscience. Nature. 10: 36–40. doi:10.1038/ngeo2848.
  14. ^ Board on Atmospheric Sciences and Climate (2013). "Abrupt Impacts of Climate Change: Anticipating Surprises". Archived from the original on 13 October 2017. Retrieved 12 December 2013.
  15. ^ Bengston, David N.; Crabtree, Jason; Hujala, Teppo (1 December 2020). "Abrupt climate change: Exploring the implications of a wild card". Futures. 124: 102641. doi:10.1016/j.futures.2020.102641. ISSN 0016-3287. S2CID 224860967.
  16. ^ Clark, P.U.; et al. (December 2008). "Executive Summary". Abrupt Climate Change. A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research. Reston, Virginia: U.S. Geological Survey. pp. 1–7.
  17. ^ a b IPCC. "Summary for Policymakers". Sec. 2.6. The Potential for Large-Scale and Possibly Irreversible Impacts Poses Risks that have yet to be Reliably Quantified. Archived from the original on 24 September 2015. Retrieved 10 May 2018.
  18. ^ a b c Mayewski, Paul Andrew (2016). "Abrupt climate change: Past, present and the search for precursors as an aid to predicting events in the future (Hans Oeschger Medal Lecture)". EGU General Assembly Conference Abstracts. 18: EPSC2016-2567. Bibcode:2016EGUGA..18.2567M.
  19. ^ "Unexpected Future Boost of Methane Possible from Arctic Permafrost". NASA. 2018.
  20. ^ a b Sahney, S.; Benton, M.J. (2008). "Recovery from the most profound mass extinction of all time". Proceedings of the Royal Society B. 275 (1636): 759–65. doi:10.1098/rspb.2007.1370. PMC 2596898. PMID 18198148.
  21. ^ a b Crowley, T. J.; North, G. R. (May 1988). "Abrupt Climate Change and Extinction Events in Earth History". Science. 240 (4855): 996–1002. Bibcode:1988Sci...240..996C. doi:10.1126/science.240.4855.996. PMID 17731712. S2CID 44921662.
  22. ^ Sahney, S.; Benton, M.J.; Ferry, P.A. (2010). "Links between global taxonomic diversity, ecological diversity and the expansion of vertebrates on land". Biology Letters. 6 (4): 544–547. doi:10.1098/rsbl.2009.1024. PMC 2936204. PMID 20106856.
  23. ^ Trenberth, K. E.; Hoar, T. J. (1997). "El Niño and climate change". Geophysical Research Letters. 24 (23): 3057–3060. Bibcode:1997GeoRL..24.3057T. doi:10.1029/97GL03092.
  24. ^ Meehl, G. A.; Washington, W. M. (1996). "El Niño-like climate change in a model with increased atmospheric CO2 concentrations". Nature. 382 (6586): 56–60. Bibcode:1996Natur.382...56M. doi:10.1038/382056a0. S2CID 4234225.
  25. ^ Broecker, W. S. (1997). "Thermohaline Circulation, the Achilles Heel of Our Climate System: Will Man-Made CO2 Upset the Current Balance?" (PDF). Science. 278 (5343): 1582–1588. Bibcode:1997Sci...278.1582B. doi:10.1126/science.278.5343.1582. PMID 9374450. Archived from the original (PDF) on 22 November 2009.
  26. ^ a b Manabe, S.; Stouffer, R. J. (1995). "Simulation of abrupt climate change induced by freshwater input to the North Atlantic Ocean" (PDF). Nature. 378 (6553): 165. Bibcode:1995Natur.378..165M. doi:10.1038/378165a0. S2CID 4302999.
  27. ^ Beniston, M.; Jungo, P. (2002). "Shifts in the distributions of pressure, temperature and moisture and changes in the typical weather patterns in the Alpine region in response to the behavior of the North Atlantic Oscillation" (PDF). Theoretical and Applied Climatology. 71 (1–2): 29–42. Bibcode:2002ThApC..71...29B. doi:10.1007/s704-002-8206-7. S2CID 14659582.
  28. ^ J. Hansen; M. Sato; P. Hearty; R. Ruedy; et al. (2015). "Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming is highly dangerous". Atmospheric Chemistry and Physics Discussions. 15 (14): 20059–20179. Bibcode:2015ACPD...1520059H. doi:10.5194/acpd-15-20059-2015. Our results at least imply that strong cooling in the North Atlantic from AMOC shutdown does create higher wind speed. * * * The increment in seasonal mean wind speed of the northeasterlies relative to preindustrial conditions is as much as 10–20%. Such a percentage increase of wind speed in a storm translates into an increase of storm power dissipation by a factor ~1.4–2, because wind power dissipation is proportional to the cube of wind speed. However, our simulated changes refer to seasonal mean winds averaged over large grid-boxes, not individual storms.* * * Many of the most memorable and devastating storms in eastern North America and western Europe, popularly known as superstorms, have been winter cyclonic storms, though sometimes occurring in late fall or early spring, that generate near-hurricane-force winds and often large amounts of snowfall. Continued warming of low latitude oceans in coming decades will provide more water vapor to strengthen such storms. If this tropical warming is combined with a cooler North Atlantic Ocean from AMOC slowdown and an increase in midlatitude eddy energy, we can anticipate more severe baroclinic storms.
  29. ^ Lenton, Tim; Rockström, Johan; Gaffney, Owen; Rahmstorf, Stefan; Richardson, Katherine; Steffen, Will; Schellnhuber, Hans Joachim (2019). "Climate tipping points – too risky to bet against". Nature. 575 (7784): 592–595. Bibcode:2019Natur.575..592L. doi:10.1038/d41586-019-03595-0. PMID 31776487.
  30. ^ "Climate change driving entire planet to dangerous "global tipping point"". National Geographic. 27 November 2019. Archived from the original on 19 February 2021. Retrieved 17 July 2022.
  31. ^ a b c Lenton, Tim (2021). "Tipping points in the climate system". Weather. 76 (10): 325–326. Bibcode:2021Wthr...76..325L. doi:10.1002/wea.4058. ISSN 0043-1656. S2CID 238651749.
  32. ^ Armstrong McKay, David; Abrams, Jesse; Winkelmann, Ricarda; Sakschewski, Boris; Loriani, Sina; Fetzer, Ingo; Cornell, Sarah; Rockström, Johan; Staal, Arie; Lenton, Timothy (9 September 2022). "Exceeding 1.5°C global warming could trigger multiple climate tipping points". Science. 377 (6611): eabn7950. doi:10.1126/science.abn7950. hdl:10871/131584. ISSN 0036-8075. PMID 36074831. S2CID 252161375.
  33. ^ 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.
  34. ^ Ripple, William J; Wolf, Christopher; Newsome, Thomas M.; Gregg, Jillian W.; Lenton, Tim; Palomo, Ignacio; Eikelboom, Jasper A. J.; Law, Beverly E.; Huq, Saleemul; Duffy, Philip B.; Rockström, Johan (28 July 2021). "World Scientists' Warning of a Climate Emergency 2021". BioScience. 71 (biab079): 894–898. doi:10.1093/biosci/biab079. hdl:1808/30278. ISSN 0006-3568.
  35. ^ Steffen, Will; Rockström, Johan; Richardson, Katherine; Lenton, Timothy M.; Folke, Carl; Liverman, Diana; Summerhayes, Colin P.; Barnosky, Anthony D.; Cornell, Sarah E.; Crucifix, Michel; Donges, Jonathan F.; Fetzer, Ingo; Lade, Steven J.; Scheffer, Marten; Winkelmann, Ricarda; Schellnhuber, Hans Joachim (14 August 2018). "Trajectories of the Earth System in the Anthropocene". Proceedings of the National Academy of Sciences. 115 (33): 8252–8259. Bibcode:2018PNAS..115.8252S. doi:10.1073/pnas.1810141115. ISSN 0027-8424. PMC 6099852. PMID 30082409.
  36. ^ Wunderling, Nico; Donges, Jonathan F.; Kurths, Jürgen; Winkelmann, Ricarda (3 June 2021). "Interacting tipping elements increase risk of climate domino effects under global warming". Earth System Dynamics. 12 (2): 601–619. Bibcode:2021ESD....12..601W. doi:10.5194/esd-12-601-2021. ISSN 2190-4979. S2CID 236247596. Archived from the original on 4 June 2021. Retrieved 4 June 2021.
  37. ^ Brovkin, Victor; Brook, Edward; Williams, John W.; Bathiany, Sebastian; Lenton, Tim; Barton, Michael; DeConto, Robert M.; Donges, Jonathan F.; Ganopolski, Andrey; McManus, Jerry; Praetorius, Summer (2021). "Past abrupt changes, tipping points and cascading impacts in the Earth system". Nature Geoscience. 14 (8): 550–558. Bibcode:2021NatGe..14..550B. doi:10.1038/s41561-021-00790-5. ISSN 1752-0908. S2CID 236504982.
  38. ^ "Heinrich and Dansgaard–Oeschger Events". National Centers for Environmental Information (NCEI) formerly known as National Climatic Data Center (NCDC). NOAA. Archived from the original on 22 December 2016. Retrieved 7 August 2019.
  39. ^ Alley, R. B.; Meese, D. A.; Shuman, C. A.; Gow, A. J.; Taylor, K. C.; Grootes, P. M.; White, J. W. C.; Ram, M.; Waddington, E. D.; Mayewski, P. A.; Zielinski, G. A. (1993). "Abrupt increase in Greenland snow accumulation at the end of the Younger Dryas event" (PDF). Nature. 362 (6420): 527–529. Bibcode:1993Natur.362..527A. doi:10.1038/362527a0. hdl:11603/24307. S2CID 4325976. Archived from the original (PDF) on 17 June 2010.
  40. ^ Farley, K. A.; Eltgroth, S. F. (2003). "An alternative age model for the Paleocene–Eocene thermal maximum using extraterrestrial 3He". Earth and Planetary Science Letters. 208 (3–4): 135–148. Bibcode:2003E&PSL.208..135F. doi:10.1016/S0012-821X(03)00017-7.
  41. ^ Pagani, M.; Caldeira, K.; Archer, D.; Zachos, C. (December 2006). "Atmosphere. An ancient carbon mystery". Science. 314 (5805): 1556–1557. doi:10.1126/science.1136110. ISSN 0036-8075. PMID 17158314. S2CID 128375931.
  42. ^ Zachos, J. C.; Röhl, U.; Schellenberg, S. A.; Sluijs, A.; Hodell, D. A.; Kelly, D. C.; Thomas, E.; Nicolo, M.; Raffi, I.; Lourens, L. J.; McCarren, H.; Kroon, D. (June 2005). "Rapid acidification of the ocean during the Paleocene–Eocene thermal maximum". Science. 308 (5728): 1611–1615. Bibcode:2005Sci...308.1611Z. doi:10.1126/science.1109004. hdl:1874/385806. PMID 15947184. S2CID 26909706.
  43. ^ Benton, M. J.; Twitchet, R. J. (2003). "How to kill (almost) all life: the end-Permian extinction event" (PDF). Trends in Ecology & Evolution. 18 (7): 358–365. doi:10.1016/S0169-5347(03)00093-4. Archived from the original (PDF) on 18 April 2007.
  44. ^ Alley, R. B.; Mayewski, P. A.; Sowers, T.; Stuiver, M.; Taylor, K. C.; Clark, P. U. (1997). "Holocene climatic instability: A prominent, widespread event 8200 yr ago". Geology. 25 (6): 483. Bibcode:1997Geo....25..483A. doi:10.1130/0091-7613(1997)025<0483:HCIAPW>2.3.CO;2.
  45. ^ Weber; Clark; Kuhn; Timmermann (5 June 2014). "Millennial-scale variability in Antarctic ice-sheet discharge during the last deglaciation". Nature. 510 (7503): 134–138. Bibcode:2014Natur.510..134W. doi:10.1038/nature13397. PMID 24870232. S2CID 205238911.
  46. ^ Gregoire, Lauren (11 July 2012). "Deglacial rapid sea level rises caused by ice-sheet saddle collapses" (PDF). Nature. 487 (7406): 219–222. Bibcode:2012Natur.487..219G. doi:10.1038/nature11257. PMID 22785319. S2CID 4403135.
  47. ^ Bond, G.C.; Showers, W.; Elliot, M.; Evans, M.; Lotti, R.; Hajdas, I.; Bonani, G.; Johnson, S. (1999). "The North Atlantic's 1–2 kyr climate rhythm: relation to Heinrich events, Dansgaard/Oeschger cycles and the little ice age" (PDF). In Clark, P.U.; Webb, R.S.; Keigwin, L.D. (eds.). Mechanisms of Global Change at Millennial Time Scales. Geophysical Monograph. American Geophysical Union, Washington DC. pp. 59–76. ISBN 0-87590-033-X. Archived from the original (PDF) on 29 October 2008.
  48. ^ McConnell; et al. (2017). "Synchronous volcanic eruptions and abrupt climate change ~17.7 ka plausibly linked by stratospheric ozone depletion". Proceedings of the National Academy of Sciences. PNAS. 114 (38): 10035–10040. Bibcode:2017PNAS..11410035M. doi:10.1073/pnas.1705595114. PMC 5617275. PMID 28874529.
  49. ^ a b Alley, R. B.; Marotzke, J.; Nordhaus, W. D.; Overpeck, J. T.; Peteet, D. M.; Pielke Jr, R. A.; Pierrehumbert, R. T.; Rhines, P. B.; Stocker, T. F.; Talley, L. D.; Wallace, J. M. (March 2003). "Abrupt Climate Change" (PDF). Science. 299 (5615): 2005–2010. Bibcode:2003Sci...299.2005A. doi:10.1126/science.1081056. PMID 12663908. S2CID 19455675.
  50. ^ Schlosser P, Bönisch G, Rhein M, Bayer R (1991). "Reduction of deepwater formation in the Greenland Sea during the 1980s: Evidence from tracer data". Science. 251 (4997): 1054–1056. Bibcode:1991Sci...251.1054S. doi:10.1126/science.251.4997.1054. PMID 17802088. S2CID 21374638.
  51. ^ Rhines, P. B. (2006). "Sub-Arctic oceans and global climate". Weather. 61 (4): 109–118. Bibcode:2006Wthr...61..109R. doi:10.1256/wea.223.05.
  52. ^ Våge, K.; Pickart, R. S.; Thierry, V.; Reverdin, G.; Lee, C. M.; Petrie, B.; Agnew, T. A.; Wong, A.; Ribergaard, M. H. (2008). "Surprising return of deep convection to the subpolar North Atlantic Ocean in winter 2007–2008". Nature Geoscience. 2 (1): 67. Bibcode:2009NatGe...2...67V. doi:10.1038/ngeo382. hdl:1912/2840.
  53. ^ "Thermodynamics: Albedo". NSIDC.
  54. ^ Lenton, Timothy M.; Rockström, Johan; Gaffney, Owen; Rahmstorf, Stefan; Richardson, Katherine; Steffen, Will; Schellnhuber, Hans Joachim (27 November 2019). "Climate tipping points – too risky to bet against". Nature. 575 (7784): 592–595. Bibcode:2019Natur.575..592L. doi:10.1038/d41586-019-03595-0. hdl:10871/40141. PMID 31776487.
  55. ^ Comiso, J. C. (2002). "A rapidly declining perennial sea ice cover in the Arctic". Geophysical Research Letters. 29 (20): 17-1–17-4. Bibcode:2002GeoRL..29.1956C. doi:10.1029/2002GL015650.
  56. ^ Malhi, Y.; Aragao, L. E. O. C.; Galbraith, D.; Huntingford, C.; Fisher, R.; Zelazowski, P.; Sitch, S.; McSweeney, C.; Meir, P. (February 2009). "Special Feature: Exploring the likelihood and mechanism of a climate-change-induced dieback of the Amazon rainforest" (PDF). PNAS. 106 (49): 20610–20615. Bibcode:2009PNAS..10620610M. doi:10.1073/pnas.0804619106. ISSN 0027-8424. PMC 2791614. PMID 19218454.
  57. ^ Praetorius, Summer; Mix, Alan; Jensen, Britta; Froese, Duane; Milne, Glenn; Wolhowe, Matthew; Addison, Jason; Prahl, Fredrick (October 2016). "Interaction between climate, volcanism, and isostatic rebound in Southeast Alaska during the last deglaciation". Earth and Planetary Science Letters. 452: 79–89. Bibcode:2016E&PSL.452...79P. doi:10.1016/j.epsl.2016.07.033.