Changes in Baltic Sea surface temperature extremes

Abstract

The probability of extreme sea surface temperature (SST) occurring seems more apparent for future in the Baltic Sea therefore its prediction and inferences are essential. This study analyzed the mean change of the SST in the Baltic Sea and calculated return periods using extreme value distributions of the 21st century. To illustrate the application of extreme value theory, annual SST maxima from the Baltic Sea regional climate model based on NEMO-LIM3 [1] were analyzed. The changes were estimated from the control simulation of the 20th century (1971-2000) and were assessed for the following projected periods 2011-2040, 2041-2070, and 2071-2099 forced by the IPCC SRES A2 emission scenario. Under that scenario, results indicate that the warm extremes (e.g. 30-year return values) will occur more frequently than those of the current condition and also show different spatial patterns. In addition, the strength of the spatial variability in the Baltic Sea will be reduced gradually towards the end of the 21st century.