Climate of extremes - Antarctica: Global Science from a Frozen Continent - page 121

Figure 4.17 Map of Antarctic precipitation distribution. (Credit: Matthew Higgins, Cooperative

Institute for Research in Environmental Sciences, University of Colorado)

The relative measure of humidity used by meteorologists, known simply as
relative humidity, indicates how much water vapour is in the atmosphere relative
to the maximum amount of water vapour the atmosphere could contain at that
temperature. The relative humidity can be viewed as being similar to the fuel gauge
in a car. When the relative humidity is 0% the atmosphere is completely dry, and
corresponds to the car is fuel gauge indicating that the fuel tank is empty. When the

relative humidity is 100% the atmosphere is said to be saturated and it contains
the maximum amount of water vapour possible. In this situation fog or clouds will
form. This situation corresponds to the fuel gauge indicating that the fuel tank is full.
The relative humidity can change if either the amount of water vapour in the

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