Lake Superior summer water temperatures are increasing more rapidly than regional air temperatures: A positive ice-albedo feedback
نویسندگان
چکیده
[1] Lake Superior summer (July–September) surface water temperatures have increased approximately 2.5 C over the interval 1979–2006, equivalent to a rate of (11 ± 6) 10 2 C yr , significantly in excess of regional atmospheric warming. This discrepancy is caused by declining winter ice cover, which is causing the onset of the positively stratified season to occur earlier at a rate of roughly a half day per year. An earlier start of the stratified season significantly increases the period over which the lake warms during the summer months, leading to a stronger trend in mean summer temperatures than would be expected from changes in summer air temperature alone. Citation: Austin, J. A., and S. M. Colman (2007), Lake Superior summer water temperatures are increasing more rapidly than regional air temperatures: A positive ice-albedo feedback, Geophys. Res. Lett., 34, L06604, doi:10.1029/ 2006GL029021.
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