A recent article and photo in the New York Times ( god only knows why this wasn't big news here in Australia) highlights how land clearing can affect rainfall patterns. The rabbit proof fence that was built across part of Western Australia in the early 20th century to try and keep the rabbits out of farmland has inadvertently highlighted stark differences between the way native vegetation and cleared farmland affect rainfall patterns.
The sky on the side of the fence with the native vegetation is rich with rain producing clouds, where as on the farmland side, the sky is clear.
Scientists are not entirely clear why this has happened, but it highlights how important sustainable farming practices are to such an arid country as Australia.
The lesson, clear all the land of native vegetation and the rain goes away!