It is not saved for sweep mode data. The source of this data is the same as that used for Nimbus SBUV processing. The entire globe is divided into 2.5 x 2.5 degree latitude and longitude cells with terrain pressure given for each cell. A total of 10,585 values are given. A two-dimensional interpolation procedure using the four closest grid points is used to find the value of terrain pressure at the start of each major frame.
Surface pressure is supplied for discrete mode data only.
This is the data required to initialize the ozone algorithm. The A-Priori Profile Information data records will contain 180 values of a priori profile coefficients and 144 values for the a priori covariance matrix elements. As the ancillary data is not time dependent, this data will be written one for each Daily 1b Data set. Albedo Correction Factors Initially, only prelaunch radiance and irradiance calibrations will be on the 1b Data Set until the Instrument Support Subsystem is implemented. The prelaunch flux ratios will be used to perform the diffuser calibration in the instrument support subsystem.