Modeling the Response of Arctic Vegetation to Increasing Atmospheric Carbon Dioxide and Climate Change

Abstract

An increase in atmospheric carbon dioxide is contributing to planetary warming that is strongest over high latitude land areas of the Northern Hemisphere. Elevated levels of atmospheric carbon dioxide and strong warming have led to changes in vegetation distribution, permafrost depth, and snow cover, which significantly affect the interactions between terrestrial ecosystems and the climate through biophysical and biogeochemical processes. With a continued rise in greenhouse gas emissions and additional warming in the high latitudes, uncertainty exists as to how the Arctic biosphere will respond in the coming decades and whether Arctic ecosystems will remain a carbon sink or instead become a source of carbon to the atmosphere. Elevated carbon dioxide and climate change can affect vegetation growth through changing the assimilation of carbon dioxide and the respiration of carbon from the vegetation and soil. Using a dynamic global vegetation model (IBIS), potential changes in both the biophysical and biogeochemical processes of Arctic vegetation were analyzed to determine how future climate change and elevated atmospheric carbon dioxide may alter their functioning and ability to store carbon.