Meterological Satellites

METEROLOGICAL SATELLITES:

Meteorological satellites designed specifically to assist. in weather predictionand monitoring, generally incorporate sensors that have very coarse spatial resolution compared to land-oriented systems. These satellites, however, afford a high frequency global coverage. USA has launched a multiple series of meteorological satellites with a wide range of orbit and sensing system designs. The first of these series is called the NOAA, an acronym for National Oceanic and Atmospheric Administration. These satetlites are in near-polar, sunsynchronous orbits similar to those of 'Landsat and IRS'. In contrast, another series of satellites which are of essentially meteorological type, called Geostationary Operational Environmental Satellite (GOES) series and Meteosat operated by European Space Agency, are geostationary, remaining in a constant relative position over the equator.

1 NOAA SATELLITES

Several generations of satellites in the NOAA series have been placed in orbit.The satellites NOAA-6 through NOAA-10 contained Advanced Very High Resolution Radiometer (AVHRR). The even-numbered missions have daylight (7.30 A.M.) north-to-south equatorial crossing and the odd-numbered missions have night time (2.30 A.M.) north-to-south equatorial crossing. The basic characteristics of these missions and the AVHRR instrument are listed in Table 4.8. Apart from routine climatological analyses, the AVHRR data have been used extensively in studies of vegetation dynamics, flood monitoring, regional soil moisture analysis, dust and sandstorm monitoring, forest wild fire mapping, sea surface temperature mapping, and various geological applications, including observation of volcanic eruptions, and mapping of regional drainage and physiographic features.

Details of NOAA Satellite and AVHRR Sensor

Characteristics of Satellite

2 GOES SATELLITES

The GOES programme is a cooperative venture between NOM and NASA. The Geo-stationary Operational Environmental Satellites (GOES) are part of a global network of meteorological satellites spaced about 70 o longitude apart around the world. The GOES images are distributed in near real-time for use in local weatherforecasting. They have also been used in certain large area analyses such as regional snow cover mapping.

3 NIMBUS SATELLITES

This is one of the ocean monitoring satellites launched in October 1978. This satellite carries the Coastal Zone Colour Scanner (CZCS) designed specifically to measure ocean parameters. The details of the six bands in which the CZCS operates and the characteristics of NIMBUS-7 satellite are presented in Table 4.10 The CZCS has been used to measure sea surface temperatures, detection of chlorophyll and suspended solids of near-shore and coastal waters.