Visible-infrared Spin-Scan Radiometer (VISSR) Atmospheric Sounder (VAS)
provides visible, infrared, and sounding measurement of the Earth, including the
presence of water vapor. Primary data from this instrument are used to estimate
cloud top temperatures, sea surface temperatures, and precipitation; determine the
vertical structure of the atmosphere; study weather systems; and observe severe
weather outbreaks. VISSR allows for both day and night cloud cover imagery.
Imaging in the visible portion of the spectrum has a resolution of 0.9 km, and in
the infrared (IR) portion a resolution of 6.9 km. These images, together with images
received from polar-orbiting satellites, are processed on the ground and then
radioed back up to GOES for broadcast in graphic form as WEFAX. The VAS instru-
ment can produce full-Earth disk images every 30 minutes, 24 hours a day.
Space Environment Monitor (SEM)
measures the condition of the Earth’s magnetic field, solar activity and radiation
around the spacecraft, and transmits these data to a central processing facility. SEM
instruments measure the ambient magnetic field vector, solar X-ray flux, and the
charged particle population. SEM sensors are designed to provide direct measure-
ment of the effects of solar activity in such a manner that data will be available in
real time for use in the generation of advisory or warning messages, and for fore-
casting and operational research.
Data Collection System (DCS)
gathers and relays environmental data made by sensors placed on various objects
(both mobile and stationary at various locations). Examples of environmental data
obtained from these sites include precipitation, river heights, ocean currents and
temperatures, water pH, wind speed and direction, and barometric pressure.
