Climate change and health in the circumpolar north.

International Journal of Circumpolar Health 64:5 2005 Human health status is the result of the complex interaction of genetic, behavioral and environmental factors. In the circumpolar north, as in all other regions, climate is a major, constantly changing component of the environment. The last 50 years have seen a steadily increasing scientific capacity to determine past climate parameters, and to investigate previously unknown climate elements, utilizing new techniques in satellite technology, for example. At the same time, the development of powerful modern computer processing has made possible great improvements in mathematical climate models. Scientific interest and rapid technologic developments culminated in the formation of the Intergovernmental Panel on Climate Change (IPCC), which published a global climate change impact assessment based on future climate change predicted by climate models (1). In this assessment, two key deficiencies were recognized. First, the Arctic data was sparse, and thus the climate models were felt to poorly represent this region. Second, the Arctic climate factors were recognized as inextricably linked to climate change in the rest of the world. For these reasons, the Arctic Climate Impact Assessment (ACIA) was undertaken. This effort lasted four years, 2000-2004, involved hundreds of scientists, and resulted in the publication of the ACIA document titled “Impacts of a Warming Arctic”. The papers in this Special Issue utilize the projections developed in the ACIA as context for the topics, conclusions, and recommendations. Broadly stated, these ACIA projections can be summarized as follows: • The present warming trend will continue, with 3-5°C mean annual warming over the next 100 years. • Winters will warm more than summers. • Mean annual precipitation will increase. • Continued melting of land and sea ice. • Increased weather variability, with a possible increase in extreme weather events. • Increasing river discharge and rising sea level.