Presenting Author: Professor Naoto Ebuchi
Vector winds observed by ASCAT on Metop-A are evaluated by comparing with buoy data and assessing the self-consistency of statistical distributions of wind speed and direction. The bias and root-mean-squared differences between the ASCAT wind speed and direction and buoy observations are -0.19 m/s and 1.5 deg., and 0.86 m/s and 18.6 deg., respectively. Though the ASCAT wind speed is slightly higher (0.2 m/s) than buoys data, the rms differences are comparable to or slightly better than those for the comparison of SeaWinds data with buoy observations. Analysis of the wind speed residual indicated that the ASCAT wind speed is systematically underestimated at wind speed higher than 15 m/s. Comparison with ECMWF wind speeds also showed a similar result. Histograms of wind directions relative to the satellite flight direction exhibited systematic directionality of ASCAT wind vectors relative to the antenna beams at low- to mid- wind speed ranges. These results suggest that further improvements of the C-band geophysical model function are needed.
2019 International OVWST Meeting
May 29-31 in Portland, Maine, USA