Weather Satellite

views updated May 23 2018

Weather satellite

The first attempt to look at Earth's weather from space occurred early in the space program of the United States. In 1959, Vanguard II was launched with light-sensitive cells able to provide information about Earth's cloud cover. Unfortunately, the satellite tumbled in orbit and was unable to return any information. Explorer VI, also launched in 1959, was more successful and transmitted the first photographs of Earth's atmosphere from space.

In 1960, the United States launched the first experimental weather satellite, TIROS 1. The acronym for Television and Infra Red Observation Satellite, TIROS 1 televised over 22,000 photos before it failed six weeks later. It detected potential hurricanes days before they could have been spotted by any other means. It watched the spring breakup of the ice in the St. Lawrence River and helped forecast weather for the Antarctic bases. TIROS 1 also used infrared detectors to measure the amount of heat radiated by the earth's surface and the clouds . Later versions of TIROS improved upon the original with television cameras that provided direct, real-time readouts of pictures to simple stations around the world. In 1970, ITQS-l was launched with the capability of not only direct-readout, automatic picture transmission but also the ability to store global images for later transmission and processing. Another successful series was called NOAA after the National Oceanic and Atmospheric Administration. Some of these satellites were placed in geostationary orbit (moving at the same speed as Earth) and thus were able to continuously observe one area . This helped in the detection of severe storms and tornadoes and provided real-time coverage at an earlier stage of cloud and frontal weather movements. Other TIROS-type satellites, such as NIMBUS (1960s) and NOAA-9 (1980s1990s), are in polar orbit, where their infrared sensors measure temperatures and water vapor over the entire globe.

Several GOES (Geostationary Operational Environmental Satellites) also cover the western and eastern hemispheres. These satellites are able to provide weather reports for places that have not been covered very well in the past: ocean regions, deserts, and polar areas. They also trace hurricanes, typhoons, and tropical storms, in the process save many lives. Their data are used to produce state-of-the-art charts showing sea-surface temperatures, information useful to the shipping and fishing industries. New satellites that probe Earth's atmosphere by day and night in all weather are being developed in many countries. Since the weather satellite is now an established tool of meteorologists all over the world, both developed and developing nations will continue to rely on these crafts.

See also Weather forecasting methods; Weather radar

Weather Satellites

views updated Jun 27 2018


WEATHER SATELLITES are robotic spacecraft that observe changes in terrestrial weather patterns. Their forecasting sharply reduces deaths from hurricanes and other violent weather. The first weather satellite, TIROS I, was launched in 1960 and functioned only eighty-nine days. TIROS (an acronym for Television and Infrared Observation Satellite) recorded television images of cloud patterns below, enabling meteorologists to track the movement of weather patterns and fronts. Weather satellites have since grown much more durable and can register more data, including wind speeds, atmospheric and surface temperatures, water temperatures, wave heights, and height of the polar ice caps. The U.S. government operates separate weather satellite programs for civilians and the military.

Weather satellites fall into two types. A geostationary satellite remains parked over a given point of the earth's equator, keeping continuous watch over a large portion of the earth from an altitude of 22,000 miles. A polarorbiting satellite flies at about 500 miles in an orbit that carries it nearly over the earth's north and south poles. This satellite views a much smaller portion of Earth than a geostationary satellite but can make more detailed observations. The U.S. government typically has maintained two geostationary satellites and two polar-orbiting satellites in orbit at all times, but satellite weather forecasting ran into a snag in 1989, when the GOES-6 failed in orbit. A replacement, GOES-8, was to have been launched on a space shuttle mission, but the Challenger shuttle explosion interrupted all shuttle launches. The replacement was further delayed until 1994 by technical problems. To fill the gap a European weather satellite was repositioned over the Atlantic Ocean to provide coverage of the eastern United States.


Burroughs, William J. Watching the World's Weather. New York: Cambridge University Press, 1991.

Hubert, Lester F. Weather Satellites. Waltham, Mass.: Blaisdell Pub. Co., 1967.

VincentKiernan/h. s.

See alsoHurricanes ; Meteorology ; Space Program .

weather satellite

views updated May 08 2018

weather satellite A satellite that senses the state of the atmosphere, e.g. by photographing cloud distribution, or by using infrared photography to record cloud temperature as an indication of the height of the cloud tops.