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The three most common types of satellite images are:
The names of these different images refer to what part of the electromagnetic spectrum the satellite sensors are sampling. It turns out that the atmosphere is transparent to different types of radiation in certain areas of the spectrum. These areas are called atmospheric windows or channels. Satellite radiometers can “see” in a wide range of electromagnetic radiation windows. The two most widely used atmospheric windows are the visible (0.6 microns) and infrared (10 to 12 microns) channels. When we study the upper troposphere we also use the water vapor channel, which includes radiation between 6.5 and 6.9 microns. Water vapor and high clouds absorb radiation in this spectral region so that the surface of the earth and low clouds are nearly obscured in water vapor images. Scientist combine information provided from all three types of images to forecast the weather, monitor forest fires, ice flows, ocean currents, and long term climate patterns from the unique global perspective that only satellites can provide. In this module, you will learn:
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