Comparison of wind data from QuikSCAT and buoys in the Indian Ocean

The performance of QuikSCAT-derived wind vectors is evaluated using in-situ data from moored buoys over the Indian Ocean. The results show that the mean differences for wind speed and wind direction are 0.37 ms-1 and 5.8 degrees, root mean square deviations are 1.57ms(-1) and 44.1 degrees and corresponding coefficients of correlation are 0.87 and 0.75, respectively. The matching between in-situ and satellite estimates seems to be better in the North Indian Ocean than in the Equatorial Indian Ocean. The effects of sea surface temperature and air-sea temperature difference on wind residuals were also investigated. In general, QuikSCAT is found to overestimate the winds. It is speculated that low wind speed during rain-free conditions and high wind speed, normally associated with rain, may be the reason for the less accurate estimation of the wind vector from QuikSCAT over the Indian Ocean.