Assessing future discharge of the river Rhine using regional climate model integrations anda hydrological model

Climate Research

W. P. A. van Deursen¹  M. V. Shabalova¹  T. A. Buishand¹ 

关键词: Climate change impact;    Regional climate model;    Climate change scenarios;    Rhine discharge;    Extreme river flows;   

DOI  :  10.3354/cr023233

来源: Inter-Research Science Publishing

【 摘 要 】

ABSTRACT: Climate change scenarios based on integrations of the Hadley Centre regional climate model HadRM2 are used to determine the change in the flow regime of the river Rhine by the end of the 21st century. Two scenarios are formulated: Scenario 1accounting for the temperature increase (4.8°C on average over the basin) and changes in the mean precipitation, and Scenario 2 accounting additionally for changes in the temperature variance and an increase in the relative variability of precipitation.These scenarios are used as input into the RhineFlow hydrological model, a distributed water balance model of the Rhine basin that simulates river flow, soil moisture, snow pack and groundwater storage with a 10 d time step. Both scenarios result inhigher mean discharges of the Rhine in winter (approx. +30%), but lower mean discharges in summer (approx. -30%), particularly in August (approx. -50%). RhineFlow simulations also indicate that the variability of the 10 d discharges increasessignificantly, even if the variability of the climatic inputs remains unchanged. The annual maximum discharge increases in magnitude throughout the Rhine and tends to occur more frequently in winter, thus suggesting an increasing risk of winter floods.This is especially pronounced in Scenario 2. At the Netherlands-German border, the magnitude of the 20 yr maximum discharge event increases by 14% in Scenario 1 and by 29% in Scenario 2; the present-day 20 yr event tends to reappear every 5 yr in Scenario1 and every 3 yr in Scenario 2. The frequency of occurrence of low and very low flows increases, in both scenarios alike.

【 授权许可】

Unknown