Polar Pathfinder Sampler (PPSM): AVHRR Polar Pathfinder 5 km (1978-1996)

The AVHRR Polar Pathfinder 5 km data set provides a time-series overview of each pole. It contains a high level of detail, yet still shows the entirety of each polar region. For the first time, daily composites of AVHRR-collected variables are compiled at a resolution suitable for process studies on a hemispheric scale. Temporal coverage begins in July 1981 and continues through the present, thereby extending the temporal coverage of upcoming MODIS and and other AM-1 products. Calibrated channel data, surface broadband albedo, surface (skin) temperature, and ancillary data, including solar zenith angles, relative azimuth angles, satellite elevation angles, time of pixel, cloud mask, orbit masks, and surface-type masks, are provided. These ancillary data allow users to apply algorithms of their choice to calculate albedo and surface temperature. Additionally, albedo and surface (skin) temperature have been compiled along with the other data sets noted above into composites at two selected local times for each day. These products are mapped to the EASE-Grid. Also included are ice motion products which include displacement vectors that provide an historical record of ice motion prior to the availability of ERS-1, ERS-2, and RADARSAT-derived ice products, and offer greater spatial coverage than is currently available from buoys or radar data for the Arctic and Antarctic. The 5 km resolution AVHRR sample data on this CD-ROM covers both poles and comprises the same products as does the full data set, with the exception of ice motion. The CD-ROM contains data for September 8, 1997. Additionally, five movies for various periods in 1988 and 1989 illustrate some of the characteristics of the 5 km data when viewed as time series. One movie illustrates a novel "background" clear-sky skin temperature application. Five km AVHRR Polar Pathfinder products were averaged into 25 km grid cells, providing browse products for the Northern and Southern Hemispheres. The 25 km browse products also provide means of analyzing conditions and trends at a more manageable data volume. Please note that only portions of the complete time series are available for distribution at the time of release of this CD-ROM.