Nimbus 6 satellite vs rawinsonde capabilities

The paper establishes rms errors in Nimbus 6 satellite data from discrepancies between satellite and rawinsonde data, compares rms errors in Nimbus 6 with those in rawinsonde data, and examines the capability of Nimbus 6 satellite data to depict such quantities as horizontal gradients of basic variables and computed variables such as vorticity and lapse rate of temperature. The capability of Nimbus 6 data is illustrated by comparisons of rms errors in computed variables obtained through a propagation-of-error method with average and near-extreme values of the variables obtained from two of NASA's Atmospheric Variability Experiments (AVE II and AVE IV). It is shown that the rms errors in Nimbus 6 basic variables (temperature, mixing ratio, geopotential height, and wind speed) are between 2 and 12 times larger than the corresponding errors in rawinsonde data. For all variables examined, the magnitude of the rms errors are smaller than the near-extreme values of the variables determined from AVE II and AVE IV data.