Climate Zones

The climate zones of the planet play a major role in the weather of any specific locale. The role is not causal, since a climate is assigned on the basis for the local weather patterns, but the climate assignment of a certain area will give you a reasonable expectation for the weather in a given area. For example Phoenix, Arizona is classified as a warm desert climate.

What does that mean? Well the Warm desert climate zone is dry; this is calculated by comparing the evapotranspiration threshold of an area with its annual rainfall. Evapotranspiration is the amount of possible evaporation from open water sources (rivers, lakes) combined with the water loss from plants in an area. If the annual rainfall is less than half of the evapotranspiration threshold, then an area is considered a desert climate.

The two major considerations in the assignment of climate zones are annual precipitation, and temperature. For example, in tropical climates, the annual precipitation is extremely large, and the temperature is fairly consistent (and consistently hot!). In arctic climates, the precipitation has a large variance, but the temperature is consistently cold.