Sea surface temperature products are produced routinely from the AVHRR instrument at global, regional, local, and coastal coverage.
This image is an example of a global product produced at 50 km resolution, available twice weekly, from NOAA-14 on 21 December 1999.
A strong heat signature (red) and an ash plume (blue haze extending from hot spot) associated with eruptions of the Mount Etna volcano in northeastern Sicily. Lava had been fountaining and flowing down the west flank of the mountain in irregular intervals over six days. Hot spots in mainland Italy were associated with wildfires.
Vegetation condition products are generated from the AVHRR instrument. The red color delineates the areas with severe vegetation stress; the colors from yellow to blue indicate fair to favorable conditions. These images compare the vegetation health conditions from 1999 (top) to 1998 (bottom).
AVHHR calibration & validation
Prior to delivery the instrument goes through a lengthy calibration campaign using a variety of external calibration targets at ambient and cryogenic temperatures. During flight the instrument goes through periodic internal calibration.
The scanning mirror uses deep space view and an internal scan position as calibration reference. Those facilities (view to space and on-board black body targets) are used for the primary calibration of the IR channels (3B, 4 and 5), that occurs at each scan cycle.
Last update: 28 June 2006