—This work assesses the accuracy of the wind speed
and wind direction forecast in the German North and Baltic
Seas by comparing measurements from offshore observation
stations in the sea with forecasts data by the German Weather
Service which have been linearly interpolated in time. The
seasonal and geographical variations are discussed by
evaluation of the RMS error and the bias of the forecast
look-ahead period up to 174 hours. The statistical evaluation
allows the forecast of threshold exceedance probabilities for the
purpose of risk analysis. The analysis is based on data from
2005 to 2010. It shows that wind speed and direction forecast
accuracy seasonally vary by 25%. Also the evaluation revealed
significant geographical variation of the wind direction forecast
bias. A negative wind speed assimilation bias was found in both
North and Baltic seas.
—Offshore, risk analysis on sea weather
forecast, wind speed and wind direction.
D. Zastrau is with ANWI Institue, HS Emden-Leer, Germany and
University of Bremen, Germany (e-mail:
M. Schlaak is with EUTEC Institute, HS Emden-Leer, Germany (email:
R. Elsner is with ANWI Institute, HS Emden-Leer, Germany (email:
O. Herzog is with TZI Bremen, Germany and Jacobs University (email:
T. Bruns is with German Weather Service (DWD) (email:
Cite:D. Zastrau, M. Schlaak, T. Bruns, R. Elsner, and O. Herzog, "Differences in Wind Forecast Accuracy in the German North and Baltic Seas," International Journal of Environmental Science and Development vol. 5, no. 6, pp. 575-580, 2014.