A satellite surface wind product benefiting from boundary-layer physics

A new relatively high resolution (0.25 degree and 6 hourly) ocean surface vector winds product is introduced. This product is based on satellite observations of surface wind speed and wind vectors, combined with sea surface temperatures (SSTs) via the University of Washington Planetary Boundary-Layer (UWPBL) model. The wind vectors and wind speeds are assimilated in a physically consistent manner through the pressure gradients in the UWPBL. In all six hour periods, the satellite coverage of winds is incomplete. In the absence of non-wind data, the small scale (50 km to <400km or greater) variability is well represented within the swaths and away from rain. This variability is largely missing in the gaps in satellite coverage. On scales >50km we have found that much of the small spatial scale wind changes in wind are closely related to changes in SST gradients. At smaller spatial scales, it seems likely that boundary-layer stability (closely related to air/sea temperature differences) is also important. The UWPBL allows us to use the SST gradients to modify the surface winds, and realistically (not only statistically) recover much of the smaller scale wind variability. We compare our wind product to the CCMP wind product, which is generated on a similar spatial/temporal grid. We characterize the similarities and differences of the two wind products. We examine the differences in small scale winds in areas between satellite wind observations.