A. A way of determining cloud thickness and altitude.
B. A way of distinguishing between wet and dry clouds.
C. A way of identifying clouds suitable for cloud seeding.
D. A way of distinguishing between “new” and “old” clouds.
Infrared satellite technology works by sensing the temperature of infrared radiation being emitted into space from the earth and its atmosphere. Basically, all objects (including water, land, and clouds), radiate infrared light. However, our eyes are not “tuned” to see this kind of light, so we don’t notice it. Weather satellites not only sense this infrared light, but they can also sense the temperature of the infrared emissions.
Visible satellite images can be thought of as photographs of the earth from space. Since they are like a photograph, they are dependent on visible light (brought by the sun). As a result, visible satellite pictures only work during daylight hours. This is the greatest drawback to using visible imagery. Also, since a visible satellite picture is basically a photograph, thicker clouds (which reflect the most sunlight) show up very bright, while thinner clouds (like cirrus) are hard to distinguish.