The Advanced Very High Resolution Radiometer (AVHRR) instrument package flies aboard the NOAA Polar Orbiter series of satellites. This series commenced with TIROS-N, launched in October 1978, and is continuing an uninterrupted history with the ongoing use of NOAA 12, 16 and 17. The satellites fly at about 833 km (518 miles) above the Earth and circumnavigate the planet approximately every 102 minutes. ION has been continuously receiving the AVHRR stream of data since August, 1993, and claims one of the most comprehensive, long-term collections of this data over the western and high Arctic.

For GINA users, the continuous, real-time, High Resolution Picture Transmission (HRPT) portion of the AVHRR data stream is the most commonly requested. Some of the projects AVHRR assists are: volcano monitoring, weather research and operations, sea ice studies, forest fire spread and smoke monitoring, large area vegetation mapping and vigor determination, sea surface temperature calculation, ocean turbidity and surface circulation, and Arctic camp logistics. To support these applications and research interests, the scanning system returns data in five spectral band widths with a resolution (at nadir) of approximately 1.1 km (.68 mile). The band widths of the five channels (in micrometers are:

1. 0.58 - 0.68 (red)
2. 0.725 - 1.10 (near-infrared)
3. Channel 3
A 1,58 - 1.64 (near-infrared)
B 3.55 - 3.93 (middle infrared)
4. 10.30 - 11.30 (thermal infrared)
5. 11.50 - 12.50 (thermal infrared)

The GINA receiving station is located on the roof of the Geophysical Institute (C.T. Elvey Building) at the University of Alaska Fairbanks.

For a detailed description of the Polar Orbiter systems, please go to: http://www2.ncdc.noaa.gov/docs/intro.htm.