Satellite Meteorology

For Grade 7-12

5

Satellite Images

Infrared Satellite Images

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.

Distinguish Cloud Features in Infrared Satellite Images

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! Please proceed to next page to explore the properties of infrared satellite images.

This Satellite Meteorology Course was developed at the Cooperative Institute for Meteorological Satellite Studies (CIMSS) located within the Space Science and Engineering Center (SSEC) at the UW-Madison. Funding was provided by the Wisconsin Space Grant Consortium (WSGC) and NOAA/NESDIS.