In this article, you will learn-
The exceptionally skilled AVHRR
AVHRR stands for Advanced Very High-Resolution Radiometer.
“Very high resolution” is somewhat of a misnomer. This is because its spatial resolution is in reality exceptionally coarse at 1.1 km.
So the “exceptionally high resolution” alludes to its day fleeting goals and return to times.
Because of its high temporal resolution, AVHRR offers services in monitoring wildfires, flooding risk, and even volcanic eruptions.
AVHRR spectral bands and specifications
The Advanced Very High-Resolution Radiometer is a multispectral sensor with six spectral bands.
This includes red, thermal, mid, and near-infrared bands. But over time, their spectral ranges have varied.
For example, AVHRR/3 channel characteristics are as follows:
|Band 1||Red||0.58-0.68||Urban, vegetation, snow/ice, daytime clouds|
|Band 2||Near IR||0.725-1.00||Vegetation, land/water boundaries, snow/ice, flooding|
|Band 3A||Mid IR||1.58-1.64||Vegetation, snow/ice detection, dust monitoring|
|Band 3B||Thermal||3.55-3.93||Surface temperature, wildfire detection, nighttime clouds, volcanic eruptions|
|Band 4||Thermal||10.30-11.30||Surface temperature, wildfire detection, nighttime clouds, volcanic eruptions|
|Band 5||Thermal||11.5-12.50||Sea surface temperature, water vapor path radiance|
AVHRR uses and applications
Because of AVHRR’s fast return to times, it has a few observing applications. For instance, AVHRR monitors vegetation change, active wildfires, flooding risk, and even volcanic eruptions.
AVHRR is the backbone for the 1km global land cover product.
The AVHRR land spread item separates backwoods types, grass, bush, cropland, and water.
By using its red and NIR band, AVHRR applies the normalized difference vegetation index (NDVI).
On account of its high return to time, it’s equipped for checking vegetation change every day.
Other remote detecting applications and uses from AVHRR incorporate estimating provincial soil dampness, environmental change, physiographic features.
40+ year history of AVHRR data
From NOAA-6 to NOAA-19, NOAA Polar-Orbiting Environmental Satellite (POES) satellites have been the essential bearer of AVHRR. Be that as it may, there have been different satellites furnished with Advanced Very High-Resolution Radiometer.
For instance, Television and Infrared Observation Satellite (TIROS) was the first to utilize AVHRR in 1978. The 4-channel radiometer on TIROS was later supplanted with the 5-channel AVHRR/2.
At last, MetOp-An and B have been propelled with this sensor. Right up ’til the present time, AVHRR still gathers satellite imagery of our evolving planet. That makes it over 40 years AVHRR has been in a circle making it one of the longest-running sensors.
Satellites equipped with AVHRR
The table below lists all of the satellites that have carried the AVHRR instrument.
|Satellite||Launch Day||End Mission|
|Television and Infrared Observation Satellite (TIROS)||October 1978||January, 1980|
|NOAA-6||June 1979||November, 1986|
|NOAA-7||June 1981||June, 1986|
|NOAA-8||March 1983||October, 1985|
|NOAA-9||December 1984||May, 1994|
|NOAA-10||September 1986||September, 1991|
|NOAA-11||September 1988||September, 1994|
|NOAA-12||May 1991||December, 1994|
|NOAA-14||December 1994||May 2007|
|NOAA-16||September 2000||June 2014|
|NOAA-17||June 2002||April 2013|