Martin Sommerkorn

WWF International Arctic Programme

The Arctic is warming...

Amplification of global warming in the Arctic will have fundamental impacts on Northern Hemisphere weather and climate.The global ocean circulation system will change under the strong influence of arctic warming.The loss of ice from the Greenland Ice Sheet has increased and will contribute substantially to global sea level rise.Arctic marine systems currently provide a substantial carbon sink but the continuation of this service depends critically on arctic climate change impacts.Arctic terrestrial ecosystems will continue to take up carbon, but warming and changes in surface hydrology will cause a far greater release of carbon.The degradation of arctic sub-sea permafrost is already releasing methane from the massive methane hydrate pool and more is expected with further warming.Arctic Climate Feedbacks have global consequences

Ice sheet melt will be the primarycontributor to future sea-level rise

Reduced sea ice amplifies warming, amplified warming spreads over land

Methane is released to the atmosphere from arctic shallow seafloor permafrost

Nature does not negotiate(Meinshausen et al., 2009)

Thank you!Download the report and accompanying material fromwww.panda.org/arctic/climatefeedbacks

******This analysis found that cumulative emissions up to 2050 relate best to describe the risk to overshoot 2 deg C of warming.

There is a limited remaining global carbon budget that cannot be exceeded.The remaining budget from fossil fuel emission and land-use change combined is 1356-1678 Gt CO2e (886-1158 Gt CO2),which corresponds to a ~20-33% risk of exceeding the 2C of warming if limited to the first half of the century (Meinshausen et al., 2009). Almost a quarter of this budget has already been used in the first decade of the century (2000-2006: 234GtCO2). Graph: The probability of exceeding 2 degC warming versus CO2 emitted in the first half of the twenty-first century.

a, Individual scenarios probabilities of exceeding 2 deg C for our illustrative default (dots; for example, for SRES B1, A2, Stern and other scenarios) and smoothed (local linear regression smoother) probabilities for all climate sensitivity distributions (numbered lines). The proportion of CMIP3 AOGCMs and C4MIP carbon-cycle model emulations exceeding 2 degC is shown as black dashed line. Coloured areas denote the range of probabilities (right) of staying below 2 degC in AR4 terminology, with the extreme upper distribution being omitted.

b, Total CO2 emissions already emitted between 2000 and 2006 (grey area) and those that could arise from burning available fossil fuel reserves, and from land use activities between 2006 and 2049 (median and 80% ranges).**