Long-term analysis of extreme wave characteristics based on the SWAN hindcasts over the Black Sea using two different wind fields

Abstract

The long-term variations of wave characteristics in the Black Sea are evaluated by using a third-generation wave model (Simulating WAves Nearshore, SWAN), forced by the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-Interim and National Centers for Environmental Prediction/Climate Forecast System Reanalysis (NCEP/CF SR) wind data, covering the period of 1979-2018. The model results were calibrated and validated with buoy measurements at seven stations along the Black Sea. The comparative study shows that the CFSR dataset predicted slightly greater significant wave heights than the ERA-Interim dataset. The greatest difference between two datasets in terms of wave characteristics was found in the northeastern part of the Black Sea. The long-term averages and the variations of long-term trends for wave characteristics show that southwestern part of the Black Sea was characterized by greater significant wave heights, longer mean wave periods and storm durations, and lower variability, while the northeastern part of the basin was characterized by lower significant wave heights, shorter mean wave periods and storm durations, and higher variability. The long-term trends indicate that the wave characteristics over the 40-year period are more likely to be exposed to higher variation on the eastern part of the Black Sea than the western part of the basin.