Analysis on potential effects of global climate change on natural runoff in the Yellow River Basin

Abstract

Water scarcity is one of the most challenging issues in natural resources at present and in future,especially in arid and semi-arid regions.In the Yellow River Basin,rapid growths of population,urbanization,and industrialization have caused ever-increasing competition for water.Any kind of changes in water resource caused by global climate change will have significant implications to such a water shortage basin.This study was conducted to evaluate the potential effects of global climate change on the mean natural annual runoff in the Yellow River Basin under different climatic scenarios of HadCM3 GCM based on the evaporation ratio function of the aridity index,which considers both climate and soil surface characteristics.Six sub-basins were divided based on the runoff producing properties.The mean precipitation and evaporation of 1961-1990 of each sub-basin were obtained based on 56 stations within and around the Yellow River Basin.The future changes in climate were the relative changes between baseline(1961-1990) and different periods(2006-2035,2036-2065,2066-2095) generated by GCM model.The delta change method was to get the climate change for each station.Simulations using HadCM3 A2 and B2 scenarios indicated that the changes in annual runoff varied from region to region within the range of-48.0% to more than 203%.In general,the potential changes in annual runoff decreased from east to west.For the Yellow River Basin,the mean annual runoff increased up to 5.0%,11.7%,and 8.1% for the A2 scenario,and the changes were 7.2%,-3.1%,and 2.6% for B2 scenario by the year of 2020,2050 and 2080,respectively.