High Density Winds Match Statistics
Radiosonde match statistics are obtained by comparing, where possible, the satellite derived wind estimate with a measurement from a collocated radiosonde. In practice, the radiosonde data from the surface to 100 mb are interpolated to pressure levels which are no more than 20 mb apart; interpolation is linear in log p for temperature and linear in p for wind components. The satellite observation is subsequently compared with each level of the interpolated profile and a "penalty function" is computed to find the level of best fit. Collocation within 1.351 degrees latitude and longitude is required for a valid comparison. Moreover, it is required that an actual measured wind (from the radiosonde) be within 50 mb of the level of best fit. If either of these conditions is exceeded, the match is rejected.
Analysis match statistics are computed by comparing the satellite derived wind with a colocated value from the GFS analysis. A 3-D interpolation is performed to calculate the analysis wind value at the location of the satellite derived estimate.
NOAA profiler match statistics are computed by comparing the satellite derived wind with a colocated value taken from the NOAA Profiler Network (NPN). The NPN provides hourly vertical wind profile data at 35 Doppler Radar sites located in 18 central US states and Alaska. More information on the NPN, as well as data displays, can be found here.