Questions about Clouds
7. What do infrared
satellite images show?
- Most things on earth emit infrared radiation (which is invisible),
continuously. This includes clouds, ice and snow, the ocean surface, land
surfaces, people, tables and chairs, cars, food, etc.
- The hotter a thing is, the more infrared radiation it
emits.
- Weather satellites orbiting the earth high above the equator can
record infrared radiation emitted by various features of the earth.
We can use computers to construct images of the (otherwise invisible) emitted
infrared radiation.
- In one version of such infrared satellite images, the coldest
features are shown in the lightest shades of gray and the warmest
features are shown in the darkest shades of gray. (Sometimes the
coldest features are shown in different colors to make them even easier to
spot. The image below is an example.)
- The tops of the deepest clouds tend to be much colder
than the earth's surface or lower clouds, so they typically show up as the
lightest features (or colored features) on infrared images, rivaled
only by snow and ice surfaces in the Arctic and Antarctic.
In this exercise you'll explore and try to characterize some
of the shapes and patterns of the deep, cold-topped clouds that are most visible
on global infrared satellite images and that can produce precipitation.
