The global warming has caused massive droughts that have led to conflicts and famines.

It is primarily farming land, and the massive drought in the Southeastern United States has decimated crops, venturing half a crop yield from 2000.

Additionally a massive drought occurs at the same instance causing over 300,000 Somalians to perish.

In John Vidal's report (22 July) on the famine in east Africa, he says the massive drought appeared "as if out of nowhere".

China unintentionally played a role in the Arab Spring due to the effects of a winter wheat crop failure and a massive Chinese drought that occurred in January 2011.

This massive drought led the Chinese to buy wheat on the international market, henceforth doubling prices and leading to civil unrest in Egypt - the world's largest wheat importer.

Although the Russians were able to grow grain as far north as the Arctic Circle, a massive drought began east of the Rocky Mountains.

The Dust Bowl was a series of dust storms caused by a massive drought that began in 1930 and lasted until 1941.

A couple of degrees is not dramatic, Hurricanes or massive drought are.

During ancient times, however, the technology had yet to be developed and they did not have the proper scientific abilities to adapt to extreme changes like massive drought.