Evaluation of All-Weather SEA Surface Wind Speed Product from GCOM-W/AMSR2 Microwave Radiometer

The all-weather sea surface wind speed (ASW) product was evaluated by using data obtained around hurricanes by airborne Stepped-Frequency Microwave Radiometers (SFMR). The SFMR data were calibrated by in situ wind measurements using dropsondes and smoothed along the flight track to much with the spatial resolution of ASW. In a period from 2012 to 2016, 233 collocated data points were obtained in 12 hurricanes. Only data points of wind speed higher than 17 m/s were utilized in the analysis. The bias and root-mean-square (rms) difference of the comparison were -1.29 and 3.59 m/s, respectively. The value of rms difference satisfies the mission requirement of 7 m/s, although slight negative bias existed.