The recycling ratio is a diagnostic measure of the potential for interactions between land surface hydrology and regional climate.
The recycling ratio for the entire world is one, and for a single point is zero.
A precipitationshed is the upwind ocean and land surface that contributes evaporation to a given, downwind location's precipitation.
In much the same way that a watershed is defined by a topographically explicit area that provides surface runoff, the precipitationshed is a statistically defined area within which evaporation, traveling via moisture recycling, provides precipitation for a specific point.
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