Climate and Rivers

Abstract

Climate, described here using the Köppen-Geiger classification, plays a dominant role in determining the total flow, interannual variability, seasonal regime, extremes of high and low flow of rivers, and the nature of river channels. Mean annual runoff is the product of the climatic water balance which in arid areas is dominated by losses to evapotranspiration and the runoff component increases as climate becomes more humid. Arid and semiarid regions with little runoff occupy nearly one third of the continents. Below about 600. mm of annual precipitation, there is a strong negative correlation between annual precipitation and the variability of annual runoff. The distribution of runoff throu..