Please note that the machine on which these AVHRR data are processed has reached its life expectancy and will no longer be available as of 02 June 2008 until further notice.
The AVHRR Polar Pathfinder Twice-Daily 1.25 km EASE-Grid Composites
are a collection of products for both poles, consisting of twice-daily
gridded and calibrated satellite channel data and derived parameters.
Data include five Advanced Very High Resolution Radiometer (AVHRR)
channels, clear sky surface broadband albedo and skin temperature,
solar zenith angle, satellite elevation angle, sun-satellite relative
azimuth angle, surface type mask, cloud mask, orbit mask, time of
acquisition, and ice motion vectors. Data are composited onto two
grids per day based on common local solar times and scan angle. Reduced-resolution data (25 km) derived from the 1.25 km data are
available to assist users in selecting these data. AVHRR local area coverage (LAC) and High Resolution Picture Transmission (HRPT) level
1b data are used to generate the Polar Pathfinder products at grid
spacings of 1.25 km. AVHRR Polar Pathfinder data extend poleward from
48.4 degrees north and 53.2 degrees south latitudes, from August 1993
through December 1998 for the Northern Hemisphere, and from April 1992
through January 1996 for the Southern Hemisphere. Data are in 1-byte and 2-byte integer grid format. Ice motion vectors are in ASCII text
format. Data are available on 8-mm tape or by ftp. Distribution formats available: North: 104 MB (2-byte), 52 MB
(1-byte), 8 MB (ice motion) South: 82 MB (2-byte), 41 MB (1-byte), 6.3
MB (ice motion).