The TIROS Operational Vertical Sounder (TOVS) has been flying on NOAA satellites since 1978, generating one of the longest and most complete satellite data records in existence. As a part of the NASA/NOAA Pathfinder Program, which was created to collect existing satellite data sets and make them available to the community, we have subsetted the TOVS global data for the Arctic region north of 60 north. The radiances were processed with the Improved Initialization Inversion (3I) algorithm, which has been modified to produce more accurate retrievals over snow and ice, gridded onto a 100 km version of the Equal-Area SSM/I Earth (EASE) grid once per 24-hour period, and presented in HDF. Because the EASE grid is becoming the standard for polar data sets, combining our data set with others such as from the SSM/I is straightforward.
The TOVS Polar Pathfinder Data Set (so-called PathP) has tremendous potential for studies of Arctic climate processes as well as spatial and temporal variability. The data set includes atmospheric temperature profiles in 39 layers, surface skin temperature, water vapor in 5 layers, total precipitable water, geometric thickness of 11 atmospheric layers, cloud amount and top height, surface type (ice versus open water), bulk boundary layer stratification, geostrophic drag coefficient, angle between the geostrophic and surface stress, day/night flag, and surface pressure from the National Center for Environmental Prediction (NCEP, ex-NMC) Reanalysis. The data set will span at least 18 years when completed in late 1998. Our presentation will illustrate fields contained in the data set, analyses of the data, and examples of applications, such as calculations of 10-meter winds, lateral energy advection, and surface radiation fluxes within the Arctic Basin