NOAA Climate Data Record (CDR) of AVHRR Polar Pathfinder (APP) Cryosphere Verison 1.0 (Version Superseded)

Note: This dataset version has been superseded by a newer version. It is highly recommended that users access the current version. Users should only use this version for special cases, such as reproducing studies that used this version. This NOAA Climate Data Record (CDR) contains the AVHRR Polar Pathfinder (APP) product. APP is a fundamental CDR comprised of calibrated and navigated AVHRR channel data (reflectances and brightness temperatures), viewing and illumination geometry (sensor scan angle, solar zenith angle, and sun-sensor relative azimuth angle), Universal Coordinated Time (UTC) of the data acquisition, and a surface type mask. The data are twice daily composites of up to 23 orbits on a 5 km Equal-Area Scalable Earth (EASE)-Grid twice daily over both poles, the Arctic and Antarctic, from 1982 to the present. The daily APP composites are centered on local solar times of 14:00 (high sun, but could be nighttime for some polar areas in winter) and 04:00 for the Arctic or 02:00 for the Antarctic. The APP covers the north polar region (Arctic) from 48.4 degrees northward, and the south polar region (Antarctic) from -53.2 degrees southward.