How do you think a regions geography influenced industrial growth?

Have you ever noticed that the countries with the hottest temperatures tend to be poor, while the colder countries tend to be richer? You can see this but looking at the maps below; the map on the left colors countries according to income per capita, while the map on the left shows average temperature. There are some exceptions to this rule, but the correlation is striking. Surely this is no coincidence; there must be something about climate which influences economic growth.