Main types of satellite images: Water vapour
A water vapour image is also taken with infrared energy, but at a slightly different wavelength.
Here instead of seeing clouds, we see “clouds” of water vapour. Water likes to absorb and emit energy at a certain infrared wavelength (6 to 7µm) and by measuring that wavelength of energy, meteorologists can detect areas of high and low moisture in the mid- and upper levels of the atmosphere.
The darker the area, the drier it is.
The image above shows the water vapour in the higher parts of the atmosphere. Jet streams commonly show up as dark lines in these types of image. In the bright white areas there is enough water vapour to form clouds.