Calorie demand and climate

[Gerard Rundell]

(Possible repeat of previous message, which seems not to hav been 
sent)

I am trying to find out how calorie requirement varies with climate.
 Specifically I want to know what the normal daily calorie 
requirement for an adult male, an adult female, and a child of 10 
would be in a temperate climate (e.g. UK) and a tropical one (e.g. 
Southern Africa).  What causes the variation?

Sorry if the last version got through and I simply cannot find it 
now.  Thanks very much to anyone who can help :-)