What Happens in the Arctic Doesn't Stay in the Arctic
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WHAT HAPPENS IN THE ARCTIC WHAT HAPPENSDOESN’T STAY IN THE ARCTIC IN THE ARCTIC DOESN’T STAY IN THE ARCTIC JUNE 2016 Greenpeace Research Laboratories Technical Report (Review) No. 04-2016 WHAT HAPPENS IN THE ARCTIC DOESN’T STAY IN THE ARCTIC Authors: Kirsten Thompson Greenpeace Research Laboratories Technical Report (Review) No. 04-2016 Date: June 2016 Design and layout: Cristina Jardón, Graphic Inside Infographic, page 12/13: Prodigioso Volcán Front Page Photo: © Rasmus Törnqvist / Greenpeace 2 Photo: © Rose+Sjölander/ Greenpeace WHAT HAPPENS IN THE ARCTIC DOESN’T STAY IN THE ARCTIC Contents 1.0 EXECUTIVE SUMMARY 5 2.0 INTRODUCTION 6 3.0 WHAT ARE THE PROCESSES THAT MAKE THE DECLINE OF ARCTIC SEA ICE AFFECT THE GLOBAL CLIMATE SYSTEM? 8 3.1 The albedo effect: an unstoppable feedback mechanism 8 3.2 Release of organic carbon from glaciers, ice-sheets, the permafrost and methane hydrates. 8 3.3 Changes in oceanic circulation patterns 9 3.4 Changes in global atmospheric circulation 9 4.1 Changing world temperatures 10 4.0 HOW CHANGES IN THE ARCTIC DON’T STAY IN THE ARCTIC: THE EVIDENCE AND PROJECTIONS 14 Hot summers in the USA and Canada 14 Warming of the Mediterranean Sea and East Asia 14 Cold winters and more snow 14 4.2 Changing precipitation 15 Wet summers in northern Europe? 15 Droughts in North America and East Asia? 15 4.3 Sea level rise 16 4.4 Weather extremes 16 4.5 More Arctic tundra fires? 19 5.0 CONCLUSIONS 20 6.0 GREENPEACE DEMANDS 23 3 WHAT HAPPENS IN THE ARCTIC DOESN’T STAY IN THE ARCTIC 4 Photo: © Rose+Sjölander/ Greenpeace WHAT HAPPENS IN THE ARCTIC DOESN’T STAY IN THE ARCTIC 1.0 EXECUTIVE SUMMARY The Arctic ecosystem is warming at more Observational and modelling studies than twice as fast as any other region indicate that, as the Arctic land ice (i.e. in the world. The total area of summer glacier sheets) disappears, sea levels sea ice in the Arctic has been decreasing are likely to rise and weather patterns over the last 30 years and this means in the northern hemisphere are predict- that significantly more heat is being ex- ed to change. These effects will most changed between the Arctic ocean and likely be geographically patchy, with the surrounding atmosphere. The Arctic hotter, drier summers in some areas, environment is integral to global climate wetter summers in other areas, and systems, and this higher heat flux not cold, stormy winters in others. Chang- only results in profound changes within ing atmospheric circulation patterns, local Arctic ecosystems, but also impacts including an altered track of the Gulf climate systems throughout the world. Stream, and ‘blocked’ planetary atmo- spheric waves are likely to contribute Scientists have been attempting to un- to these extreme climatic changes. Ex- derstand these remote climatic chang- treme weather events are likely to be es but research is still in its infancy; the more common in this future world with underlying processes are highly com- a higher likelihood of heat waves, floods plex. However, there appear to be caus- and extreme storms. This report gives a al links between the loss of the Arctic brief overview of how a warmer Arctic is ice sheets and changes in large-scale driving climatic changes in other areas atmospheric circulation patterns, oce- of the world, and of the current scientif- anic circulation and temperature gradi- ic evidence that describes the process- ents in the northern hemisphere. The es underlying these changes. effects of these changes are difficult to measure, but in years when the Arc- The area within the Arctic Circle is tic has been particularly warm, certain around 6% of Earth’s surface area, yet persistent and anomalous weather pat- is currently afforded no legally binding terns have been observed. As the Arc- international protection. Greenpeace tic warms and the ice recedes further, demands urgent protection of Arctic feedback mechanisms such as reduced ecosystems through a network of pro- reflective ability of the ice (surface albe- tection that will actively and adaptively do) and the release of harmful green- manage exploitation, encroachment house gases from their long-term stor- throughout the Arctic. age in the Arctic permafrost will further add to global climate change. 5 WHAT HAPPENS IN THE ARCTIC DOESN’T STAY IN THE ARCTIC 2.0 INTRODUCTION ‘Abrupt climate change is defined by at a rate of at least 3.5-4.1 % per decade the Intergovernmental Panel on Climate in the last 30 years.1 This change is most Change (IPCC) as a large-scale change in dramatic in summer and autumn with the climate system that takes place over around a 50 % decrease in ice cover a few decades or less, persists (or is an- since satellite records began. The mean ticipated to persist) for at least a few thickness of the ice at the Arctic in sum- decades and causes substantial disrup- mer has also declined by approximate- tions in human and natural systems.’1 ly 40 %, equating to a 75-80 % loss in volume.3, 4 Sea surface temperatures in This ‘abrupt climate change’ era is now the region have been determined to be a reality for us all. Arctic ice, the north- higher than at any time in the last 1,450 ern cryosphere, is an integral part of the years.1 The underlying cause of this earth’s climate systems and has under- warming is, of course, increased con- gone rapid changes over the last century. centrations of the many greenhouse gases, and subsequent warming of the The Arctic region has warmed more global oceans and changes in weather than two times as fast as any other area patterns resulting in more warm moist of the world in the previous few decades air in the Arctic in summer.5, 6 and is known to be more sensitive to the effects of global warming in what The decline in Arctic sea ice cover is is called ‘Arctic amplification’.2 The IPCC not only an indicator of global climate has stated, with very high confidence that the Arctic sea ice extent has decreased 3 Kwok, R. & Rothrock, D. A. (2009). Decline in Arctic sea ice thickness from submarine and ICESat records: 1958– 2008. Geophysical Research Letters 36: L15501. 1 Stocker et al. (2013). Technical Summary. In: Climate 4 Overland, J. E., Wang, M., Walsh, J. E. & Stroeve, J. C. Change 2013: The Physical Science Basis. Contribution (2014). Future Arctic climate changes: adaptation and of Working Group I to the Fifth Assessment Report of the mitigation timescales. Earth’s Future 2: 68–74. Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. 5 Vihma, T. (2014). Effects of Arctic sea ice decline on Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge weather and climate: A review. Survey Geophysics 35: University Press, Cambridge, United Kingdom and New 1175-1214. York, NY, USA. 6 Marshall, J. et al. (2014). The ocean’s role in polar climate 2 Cohen et al. (2014). Recent Arctic amplification and ex- change: asymmetric Arctic and Antarctic responses to treme mid-latitude weather. Nature Geoscience 7: 627- greenhouse gas and ozone forcing. Philosophical Trans- 637. actions of the Royal Society A 372: 20130040. 6 WHAT HAPPENS IN THE ARCTIC DOESN’T STAY IN THE ARCTIC change; it also plays a vital role as an im- and will do so further as the ice extent portant positive feedback system that declines, putting local ecosystems un- affects other areas of the world. The sea der acute threat. Increased tempera- ice acts as an insulating blanket, reduc- tures will likely induce broad ecosystem ing the exchange of heat and water be- shifts, changing many habitats for Arctic tween the atmosphere and the ocean species, and allowing unwanted ‘alien’ (and the generation of waves). The ice species to move northwards. is also highly reflective, and this surface ‘albedo’ serves to reflect the sun’s en- As well as these ‘local’ changes that will ergy back into space, contributing to a impact directly on Arctic biodiversity cooling effect. As the sea ice melts, this and livelihoods, there will be more ‘re- reflective surface is replaced by a rela- mote’ effects in other global areas. Cli- tively dark ocean surface, reducing the mate change is known to be affecting amount of sunlight reflected. The less weather, and ecosystems, within the sunlight that is reflected, the more heat Arctic, but there is also a growing body the planet absorbs, making it more un- of evidence that links the melting of po- likely that ice will reform in the Arctic lar ice sheets to changes in other areas region. Black carbon produced from, or the world. The mechanisms behind for example, gas flares and emissions these large-scale changes are not well from ships engines, induces further cli- understood and there has been con- mate change effects by making the ice siderable research effort recently to try darker and more likely to melt. There- and better understand the broad pro- fore, mediating these sources of black cesses that are responsible. carbon from activities within the Arctic and across the globe will be a vital part of strategies aimed at slowing down the rate of melting.7 Some studies suggest that the whole Arctic region could be free of sea ice in summer by 2050.8 Though the Arc- tic is still relatively remote, an Arctic free from sea-ice will make it ever more possible access to the many Arctic re- sources; oil and gas, fish stocks and shipping lanes.