Vegetation greening accelerates surface warming and sea-ice melting over the Arctic and high-latitude regions

This study suggests a possible positive vegetation feedback over the Arctic and high-latitude region in association with anthropogenic global warming. By simulating the Community Climate System Model 3 (CCSM3) coupled with a dynamic global vegetation model (DGVM), potential vegetation change under a doubled CO₂ situation and its feedback influence on surface warming over the Arctic/high-latitude region are examined. We performed two baseline experiments under the present and doubling CO₂ concentration using the CCSM3-DGVM. Then, an additional simulation without DGVM was performed under doubling CO₂ concentration with the prescribed vegetation taken from the present CO₂ simulation. Our model experiments indicate that a vegetation change in high-latitudes may induces substantial alternation of climate change in the Arctic/high-latitude during warm and cold seasons. When the interactive vegetation is included in the future climate simulation, the warming in high-latitude continent appears to be significantly amplified. Furthermore, the Arctic sea ice exhibits considerable decline both in areal extent and thickness associated with the vegetation feedback effect. The present results demonstrate that a conspicuous climatic change can take place in the Arctic region from the vegetation-climate feedback.