Polar Terrestrial Ecology

Abstract

The low-temperature regimes of the polar regions affect biological activity such as growth and reproductive processes both directly and indirectly by controlling the timing and length of the snow-free period during which plants grow and most biological activity occurs. While climate exerts strong impacts on biological activity, the biosphere contributes to the exchange of greenhouse gases and energy with the atmosphere through a variety of feedback mechanisms that have resulted in net cooling in the past, but are likely to lead to warming in the future. The Arctic is characterized by large land masses, surrounding a polar ocean, that connect many of the biota with floras and faunas further south. In contrast, Antarctica is a polar land mass separated from neighboring land masses. Only a small area is seasonally ice free, and terrestrial biodiversity is generally much lower than in the Arctic. The polar regions are undergoing climate change that is more rapid than elsewhere on the Earth. This is already leading to changes in species’ ranges and abundance. However, there is considerable variability in climate impacts between the two regions and within each. Although some species might be lost, not all the changes will be disadvantageous to society.