Why and how are rainfall patterns changing?
As a result of global warming, the world’s climate is changing and its effect is being felt the world over. And one of the most important parameters of climate is rainfall. Just as there is a direct relationship between climate and agriculture, so is there one between rainfall and agriculture. So when rainfall patterns change, its effect is directly felt on cropping patterns worldwide. Again, as a result of depletion of the ozone layer, there will be more heat trapping gases in the atmosphere, which, according to climate models, will shift rainfall/precipitation patterns in two major ways. The first shift is in strengthening the current patterns, which means the wet regions would get wetter and dry regions would get drier. This is because warmer air as a result global warming traps more water vapour, and scientists predict that this additional water will fall in the already wet parts of the earth. The second shift is due to changes in atmospheric circulation, because of which storm tracks [the narrow zones in seas and oceans along which storms travel, driven by prevailing winds] would move away from the equator and towards the poles.