There is a significant rain shadow effect east of the Rockies. One prime example is Denver. Over the course of a year it would typically receive ~20 inches of rain, but many locations to the west of the continental divide receive as much as 40 inches of rain a year. (It's important to note that the rain shadow effect only impacts storms and winds traveling against the mountains. If a storm travels south to north, the effect is severely diminished and can result in a situation where the lee side of the mountains receives more rainfall than the wind side of the mountains.
Well if you are adding sides to something then that makes that object HAVE to go bigger. That will affect the area. So making it bigger by forcing more sides onto a object.This way making you area getting bigger. Hope that helped. :) :) :) :).
<span>Waters in the eastern Pacific steadily gets warmer
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El Nino is caused by the periodic shift in wind speed and direction in the tropical eastern Pacific which leads to changes in sea Surface temperatures.