Comparison of HOAPS, QuikSCAT, and Buoy Wind Speed in the Eastern North Atlantic and the North Sea

Abstract

A systematic investigation and comparison of near-surface marine wind speed obtained from in situ and satellite observations, a reanalysis, and a reanalysis-driven regional climate model (RCM) are presented for the eastern North Atlantic and the North Sea. Wind-speed retrievals from QuikSCAT Level 2B 12.5 km and HOAPS-3-S are analyzed. The root-mean-square error (rmse) between QuikSCAT and buoy 10-m equivalent neutral wind (EQNW) is 1.50 (1.87) $hbox{m}! cdot! hbox{s}^{-1}$ using a colocation criteria of 0.1$^{circ}$ and 0.06$^{circ}$ (0.3$^{circ}$ and 0.2$^{circ}$) in longitudinal and latitudinal distances from buoy locations and within 10 (20) min, demonstrating that QuikSCAT's mission requirement of providing wind speed with an rmse of 2 $hbox{m}! cdot! hbox{s}^{-1}$ is met for the investigated area. The influence of three different stability and anemometer height correction algorithms for buoy wind speed on the buoy/QuikSCAT error is assessed: EQNW gives the best agreement with QuikSCAT data; however, differences are smaller than the buoy measurement error. The rmse between HOAPS and buoy wind converted to 10 m by the logarithmic wind profile is 2.27 (2.36) $hbox{m} cdot! hbox{s}^{-1}$ using a colocation of $0.1^{circ}! times! 0.06^{circ} (0.3^{circ}! times! 0.2^{circ})$ and within 10 (20) min. QuikSCAT shows good agreement with buoy wind for speeds up to 20 $hbox{m}! cdot! hbox{s}^{-1}$. HOAPS shows an underestimation of high wind speeds beyond 15–20 $hbox{m}! cdot! hbox{s}^{-1}$ probably due to a saturation of the return signal. The rmse between buoy wind speed and the National Centers of Environmental Prediction/Nati- onal Center for Atmospheric Research Reanalysis (NRA R1) and the spectrally nudged RCM REMO (SN-REMO) are 2.2 and 2.5 $hbox{m}! cdot! hbox{s}^{-1}$, respectively.