| All objects emit radiation in amounts related to their temperature and their ability to emit radiation.
An infrared (IR) instrument provides information on the temperature of land, water, and clouds by measuring
the infrared radiation emitted from surfaces below the satellite. The radiant energy measured by infrared radiometers
is converted to a temperature. In infrared images, cold objects are white and hot surfaces appear black.
Explore the properties of infrared satellite images by clicking on this hands-on activity. IR imagery can be used to distinguish low clouds from high clouds. Low clouds are relatively warm and appear gray in satellite IR images. Thick cold clouds, like the tops of thunderstorms, appear bright white. An obvious advantage of IR satellite images over visible images is that IR images are available day and night. The best way to become familiar with common IR images is by looking at them!
Continue to the next page
Go back to the previous page |