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per capita vary greatly, with North America continuing to be far ahead of all other regions (IEA, 2013

IEA (International Energy Agency). 2013,CO2 Emissions from fuel combustion, Highlights. IEA Statistics. Paris.. .

). Emissions per unit of GDP decreased across all of the largest emitters,9 particularly in China and Russia, due to increasing energy efficiency along the energy value chain, among other improvements. However, this has not been sufficient to compensate for increasing emissions per capita: for example, India and China respectively doubled and tripled their per capita emissions between 1990 and 2011 (OECD and IEA, 2013

OECD (Organisation for Economic Co-operation and Development) and IEA (International Energy Agency). 2013,World Energy Outlook 2013, Executive Summary. Paris.. .

Globally, half of the emissions budget that was established in order to limit climate change to 2°C had already been depleted by 2011 (IPCC, 2013

IPCC (Intergovernmental Panel on Climate Change). 2013,Climate Change 2013: The Physical Science Basis, Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Full Report. Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley, eds. Camb. .

). If current emissions continue, this budget will be completely exhausted by 2045, consequently leading to a temperature change well above 2°C.

Due to processes such as changes in ice sheets, ocean warming, vegetation change occurring over long time scales and complex feedback, the climate will continue to be affected by these changes for hundreds or perhaps thousands of years even if temperatures are stabilized (ibid.). Therefore, even if emissions were to be capped today, climate change would continue to generate risk and create “reasons for concern” (see Box 12.3). These include climate-related extremes such as floods, cyclones, wildfires, droughts and heat waves, as identified with very high confidence by the IPCC (IPCC, 2014

IPCC (Intergovernmental Panel on Climate Change). 2014,Climate Change 2014: Impacts, Adaptation, and Vulnerability, Working Group II. Cambridge and New York: Cambridge University Press.. .

). In turn, those extremes would alter ecosystems, the supply of food and water, urban systems, and ultimately human well-being. Climate-related hazards will also continue to exacerbate existing vulnerabilities and exposures (IPCC, 2012

IPCC (Intergovernmental Panel on Climate Change). 2012,Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation, Full Report. (Field, C.B., V. Barros, T.F. Stocker, D. Qin, D.J. Dokken, K.L. Ebi, M.D. Mastrandrea, K.J. Mach, G.-K. Plattner, S.K. Al-len, M. Tignor and P.M. Midgley, eds.). A Special Report of Working Groups I and II of the Inter-governmental Panel on. .

, 2014). If emissions continue to grow unchecked, that risk can become catastrophic.

Box 12.3 The five “reasons for concern” (RFCs) of the IPCC’s Fifth Assessment Report

Dangerous anthropogenic, i.e. human-induced, climate change will continue to drive risk. There are five “reasons for concern” that scientists and policymakers have identified as critical to human, economic and ecosystem well-being:

1. Unique and threatened systems: Climate change will affect already threatened ecosystems and cultures with warming of 2°C. Arctic sea ice and coral reef systems that have particularly low adaptive capacities will be in severe danger.

2. Extreme weather events: Risks from extreme events are already moderate and expected to rise with increasing temperatures. Higher levels of warming may exacerbate risks from certain types of events, such as heat waves.

3. Distribution of impacts: Unevenly distributed risks generally affect disadvantaged communities the most. Climate change impacts are already known to be regionally differentiated, with high risks of unevenly distributed impacts for warming above 2°C.

4. Global aggregate impacts: The risks of global aggregate impacts encompassing both biodiversity and the global economy are moderate with warming of 1°C to 2°C. Aggregate impacts increase with rising temperatures, leading to high risks associated with warming of 3°C or more.

5. Large-scale singular events: The risks associated with abrupt and irreversible changes in some physical systems and ecosystems are moderate for warming between 0°C and 1°C, with Arctic ecosystems and coral reef systems already experiencing irreversible changes. Disproportionate increases in risks are expected as temperatures change between 1°C and 2°C, with high risks associated with 3°C or more warming due to the potential of sea level rise from ice sheet loss.

(Source: IPCC, 2014

IPCC (Intergovernmental Panel on Climate Change). 2014,Climate Change 2014: Impacts, Adaptation, and Vulnerability, Working Group II. Cambridge and New York: Cambridge University Press.. .

	241 per capita vary greatly, with North America continuing to be far ahead of all other regions (IEA, 2013 x IEA (International Energy Agency). 2013,CO2 Emissions from fuel combustion, Highlights. IEA Statistics. Paris.. . ). Emissions per unit of GDP decreased across all of the largest emitters,9 particularly in China and Russia, due to increasing energy efficiency along the energy value chain, among other improvements. However, this has not been sufficient to compensate for increasing emissions per capita: for example, India and China respectively doubled and tripled their per capita emissions between 1990 and 2011 (OECD and IEA, 2013 x OECD (Organisation for Economic Co-operation and Development) and IEA (International Energy Agency). 2013,World Energy Outlook 2013, Executive Summary. Paris.. . ). Globally, half of the emissions budget that was established in order to limit climate change to 2°C had already been depleted by 2011 (IPCC, 2013 x IPCC (Intergovernmental Panel on Climate Change). 2013,Climate Change 2013: The Physical Science Basis, Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Full Report. Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley, eds. Camb. . ). If current emissions continue, this budget will be completely exhausted by 2045, consequently leading to a temperature change well above 2°C. Due to processes such as changes in ice sheets, ocean warming, vegetation change occurring over long time scales and complex feedback, the climate will continue to be affected by these changes for hundreds or perhaps thousands of years even if temperatures are stabilized (ibid.). Therefore, even if emissions were to be capped today, climate change would continue to generate risk and create “reasons for concern” (see Box 12.3). These include climate-related extremes such as floods, cyclones, wildfires, droughts and heat waves, as identified with very high confidence by the IPCC (IPCC, 2014 x IPCC (Intergovernmental Panel on Climate Change). 2014,Climate Change 2014: Impacts, Adaptation, and Vulnerability, Working Group II. Cambridge and New York: Cambridge University Press.. . ). In turn, those extremes would alter ecosystems, the supply of food and water, urban systems, and ultimately human well-being. Climate-related hazards will also continue to exacerbate existing vulnerabilities and exposures (IPCC, 2012 x IPCC (Intergovernmental Panel on Climate Change). 2012,Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation, Full Report. (Field, C.B., V. Barros, T.F. Stocker, D. Qin, D.J. Dokken, K.L. Ebi, M.D. Mastrandrea, K.J. Mach, G.-K. Plattner, S.K. Al-len, M. Tignor and P.M. Midgley, eds.). A Special Report of Working Groups I and II of the Inter-governmental Panel on. . , 2014). If emissions continue to grow unchecked, that risk can become catastrophic. Box 12.3 The five “reasons for concern” (RFCs) of the IPCC’s Fifth Assessment Report Dangerous anthropogenic, i.e. human-induced, climate change will continue to drive risk. There are five “reasons for concern” that scientists and policymakers have identified as critical to human, economic and ecosystem well-being: 1. Unique and threatened systems: Climate change will affect already threatened ecosystems and cultures with warming of 2°C. Arctic sea ice and coral reef systems that have particularly low adaptive capacities will be in severe danger. 2. Extreme weather events: Risks from extreme events are already moderate and expected to rise with increasing temperatures. Higher levels of warming may exacerbate risks from certain types of events, such as heat waves. 3. Distribution of impacts: Unevenly distributed risks generally affect disadvantaged communities the most. Climate change impacts are already known to be regionally differentiated, with high risks of unevenly distributed impacts for warming above 2°C. 4. Global aggregate impacts: The risks of global aggregate impacts encompassing both biodiversity and the global economy are moderate with warming of 1°C to 2°C. Aggregate impacts increase with rising temperatures, leading to high risks associated with warming of 3°C or more. 5. Large-scale singular events: The risks associated with abrupt and irreversible changes in some physical systems and ecosystems are moderate for warming between 0°C and 1°C, with Arctic ecosystems and coral reef systems already experiencing irreversible changes. Disproportionate increases in risks are expected as temperatures change between 1°C and 2°C, with high risks associated with 3°C or more warming due to the potential of sea level rise from ice sheet loss. (Source: IPCC, 2014 x IPCC (Intergovernmental Panel on Climate Change). 2014,Climate Change 2014: Impacts, Adaptation, and Vulnerability, Working Group II. Cambridge and New York: Cambridge University Press.. . .)	Page 1 Page 10 Page 20 Page 30 Page 40 Page 50 Page 60 Page 70 Page 80 Page 90 Page 100 Page 110 Page 120 Page 130 Page 140 Page 150 Page 160 Page 170 Page 180 Page 190 Page 200 Page 210 Page 220 Page 230 Page 231 Page 232 Page 233 Page 234 Page 235 Page 236 Page 237 Page 238 Page 239 Page 240 Page 241 Page 242 ->Page 243 Page 244 Page 245 Page 246 Page 247 Page 248 Page 249 Page 250 Page 251 Page 252 Page 253 Page 254 Page 255 Page 260 Page 270 Page 280 Page 290 Page 300 Page 310