Arctic Climate Feedbacks: Global Implications

Human-induced climate change has affected the Arctic earlier than expected. In addition to the regional consequences of arctic climate change are its global impacts. A frozen Arctic plays a central role in regulating Earth's climate system. A number of critical arctic climate feedbacks affect the global climate system, and many of these are now being altered in a rapidly warming Arctic. There is emerging evidence and growing concern that these feedbacks are beginning to accelerate global warming significantly beyond the projections currently being considered by policymakers. While the important role of the Arctic in the global climate system has long been recognized, recent research contributes much to the understanding of key linkages. At the same time, the science assessing the growing regional and global consequences of arctic climate impacts is rapidly maturing.

A recently released unprecedented report by the WWF describes the most recent findings regarding major arctic feedbacks of global significance for coming decades. It provides a comprehensive and up-to-date picture of why and how climate change in the Arctic matters for the rest of the world and is thus relevant for today's policy decisions regarding reductions in atmospheric greenhouse gases.

Climate change in the Arctic is affecting the rest of the world by altering atmospheric and oceanic circulation that affect weather patterns, the increased melting of ice sheets and glaciers that raise global sea level, and changes in atmospheric greenhouse gas concentrations. The most recent science shows that numerous arctic climate feedbacks will make climate change more severe than indicated by other recent projections, including those of the Intergovernmental Panel on Climate Change Fourth Assessment report (IPCC 2007). Some of the feedbacks may even interact with each other. Up-to-date analyses of the global consequences of arctic change highlight the need for ongoing critical review of the thresholds of dangerous human interference with the climate system, and demand increased rigour to stay below these thresholds through an ambitious global effort to reduce atmospheric greenhouse gases. Global feedbacks already arising from arctic climate change suggest that anything but the most ambitious constraints on greenhouse gas concentrations may not be sufficient to avoid such interference.