Future wind, wave and storm surge climate in the northern North Atlantic

In this paper we consider a possible change in future wind, wave, and storm surge climate for the regional seas northeast of the Atlantic: the northern North Atlantic. Conclusions are based on a statistical analysis of the results derived with state-of-the-art wave and storm surge models run for two 20 yr time-slice periods, one for the period 1980 to 2000 (control climate) and one for the period 2030 to 2050 (future climate). Forcing was derived by extracting atmospheric wind and sea level pressure from a state-of-the-art regional atmospheric climate model for the same two 20 yr periods. These regional atmospheric simulations constitute dynamical downscales of the Max Planck Institute's global scenario which includes greenhouse gases, sulphate aerosols (direct and indirect effects) and tropospheric ozone. Generally the changes we found are small. However, there are some important exceptions, such as a significant increase in all variables in the Barents Sea and a significant reduction in wind and waves north and west of Iceland. Also, there is a significant increase in wind speed in the northern North Sea and westwards in the Atlantic Ocean, and a comparable reduction southwest of the British Isles in the autumn. The same change is suggested for wave height, but this is not statistically significant. There is a significant increase in the seasonal 99 percentile of the sea level in autumn in the southwest part of the North Sea. These results are consistent with earlier studies predicting a rougher maritime climate in the northern North Sea in autumn.