Weather Satellites
The world's first meteorological satellite, was launched from Cape Canaveral on April 1, 1960. Named TIROS for Television Infrared Observation Satellite, it demonstrated the advantage of mapping the earth's cloud cover from satellite altitudes. TIROS showed clouds banded and clustered in unexpected ways. Sightings from the surface had not prepared meteorologists for the interpretation of the cloud patterns that the view from an orbiting satellite would show.
TIROS was a polar orbiting satellite. Polar orbiting satellites (POES) continued to be used today and offer the advantage of daily global coverage, by making nearly polar orbits roughly 14.1 times daily. Since the number of orbits per day is not an integer, the orbital tracks do not repeat on a daily basis. Currently in orbit we have morning and afternoon satellites, which provide global coverage four times daily.
The geostationary (GOES) satellites were placed in orbit beginning in 1966. Unlike POES satellite, GOES satellites orbit at an altitude of 22,236 miles (35,786 km). At this distance the satellite completes one orbit of the earth in 24 hours. The net result is the satellite appears stationary, relative to the earth. This allows them to hover continuously over one position on the surface. Because they stay above a fixed spot on the surface, they provide a constant vigil for the atmospheric "triggers" for severe weather conditions such as tornadoes, flash floods, hail storms, and hurricanes.
There are advantages and disadvantages to each kind of orbit.
Advantages | Disadvantages | |
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Polar Orbits |
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Geostationary orbits |
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