Observed relationship between Arctic sea ice, cloud, and solar radiation and its implication for ice-albedo feedback

Abstract

This study demonstrates that absorbed solar radiation (ASR) at the top of the atmosphere in early summer (May-July) plays a precursory role in determining the Arctic sea ice concentration (SIC) in late summer (August-October). The monthly ASR anomalies are obtained over the Arctic Ocean (65°N-90°N) from the Clouds and the Earth's Radiant Energy System during 2000-2013. The ASR anomaly changes primarily with cloud variation that determines relative contributions of cloud and surface albedo to the ASR. We found that the ASR anomaly in early summer is significantly negatively correlated with the SIC anomaly in late summer (correlation coefficient, r ？ -0.8 with a lag of 1 to 4 months). The region exhibiting high (low) ASR anomalies and low (high) SIC anomalies varies yearly. This intimate delayed ASR-SIC relationship is not represented in most of current climate models. Rather, the models tend to over-emphasize internal sea ice processes in summer. Implication of the observed results for ice-albedo feedback will be presented.