| Summary: | interannual and decadal variations for the Arctic region in July. The satellite record of Earth radiation budget demonstrates that the effect of melting ice on the Arctic Ocean has increased the net radiation of the region from 72.5oN to the North Pole from 2 +/-3 W-m-2 to 9 +/-3 W-m-2 during the two decade period between 1985 to 2004. Most of this increase is due to the decrease of albedo as the ice cover is replaced by dark ocean, resulting in increased absorbed solar radiation. Only a small part is due to changes of outgoing longwave radiation. The net radiation flux increases by 0.43 W-m-2 for every 1 % decrease in ice cover (relative to ice cover in 1979). Maps quantify the ice-feedback effect on radiation, which includes the effects of the changing surface conditions on the clouds and subsequently the effects of these clouds on the top of atmosphere albedo. Over northern Canada and western Russia, the absorbed solar radiation decreased significantly. Large interannual variations are also noted and require further study. 1.
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