Since 1895, wrote Tim Worstall for Forbes, only the extraordinary droughts of the 1930s and 1950s have covered more land area than the current drought.

FORBES: Beneath a Parched Surface, the Great Midwest Drought of 2012 Doesn't Go Social

Extreme droughts currently cover about 2% of the world's land area, and that is going to spread to about 10% by 2050.

BBC: Man with dead camel in desert. Image: Jim Loring/Tearfund