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Monthly kinematic stress fields are produced using a monthly average of kinematic stresses determined from scatterometer swaths. These products are on a 0.5x0.5o grid. This approach bins the satellite swath observations (in 0.5x0.5o bins) and smoothed with a 1-2-1 filter (forward and backward) applied once in each spatial dimension. The tropical kinematic stresses are quite smooth without any smoothing. The smoothed kinematic stresses can be viewed.
This kinematic stress product has several advantages over other wind and kinematic stress products. It is the first gridded wind product with remotely sensed fields of kinematic stresses. Kinematic stress is normally determined as a function of wind speed and atmospheric stability, and occasionally other parameters. There is considerable uncertainty in such calculations of kinematic stress. This problem is further compounded for scatterometers, because scatterometer 'wind observations' are 'equivalent neutral winds' rather than winds. The differences between equivalent neutral winds and winds are usually small; however, they can result in considerable differences in kinematic stress products. Furthermore, these differences are spatially and temporally systematic, which is an important consideration in applications such as forcing ocean models. This relatively direct approach bypasses these problems by determining the kinematic stress directly from the observed backscatter. The data set should be considered as research quality.
A manuscript describing this data set in review.
The technique for determining kinematic stresses directly from scatterometer observations is described in
Weissman, D. E., K. L. Davidson, R. A. Brown, C. A. Friehe, and F. Li, The relationship between the mircrowase radar cross sectionand both wind speed and kinematic stress: Model function studies using Frontal Air-Sea interaction experiment data, J. Geophys. Res., 99, 10087-10108, 1994