how many temperature or heat zones the earth has been divided?

Answer 1

the earth has been divided into three temperature or heat zones

Answer 2

There are more than three.

Answer 3

Heed drwls's answer. There are more than three:

http://www.google.com/search?hl=en&source=hp&biw=1366&bih=643&q=how+many+temperature+zones+on+earth&oq=how+many+temperature+zones+on+earth&aq=f&aqi=&aql=&gs_sm=e&gs_upl=15575l31292l0l31977l57l55l7l21l21l1l348l5040l0.5.10.5l20l0

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