How Do Satellite Photos Work?

Most of the time, what you're seeing is not simply a photograph from space.SEATTLE - Satellite photos are a staple of TV weathercasts. But most of the time, what you're seeing is not simply a photograph from space. Otherwise, you'd only be able to see the clouds during the daylight hours.

Instead, to show clouds anytime, the most common satellite photos use infrared technology, which uses temperature instead of visible light to "see."

Since the atmosphere gets colder as you rise in altitude, the satellite can not only detect the cooler clouds from the warmer ocean and land areas day and night, but they can discern high clouds from low clouds. Tall, storm clouds have colder tops, so they usually come out white, while warmer, lower clouds like fog come out looking darker.

Visible-light satellite photos are useful in detecting fog and low clouds. But as mentioned earlier, they only work during the day.

For More Information:

KOMO Satellite Photos: www.komotv.com
Visible Satellite of Washington (daylight hours only) -- www.atmos.washington.edu.