13064

11932

كارشناسي ارشد

مديريت منابع آب

اصفهان: دانشگاه صنعتي اصفهان، دانشكده عمران

۱۳۹۶

ده، [۹۸]ص.: مصور، جدول، نمودار

آزاده احمدي

اميد بزرگ حداد، محمدحسين گل محمدي

1396/09/25

كتابنامه

عمران

مهندسي عمران

ID11932

Evaluating the impacts of climate change on the occurrence ofmeteorological and hydrological droughts considering the uncertainty of GCM models and emission scenarios the case study of Karkheh basin Niloofar Salimian niloofar s69@gmail com June 21 2017 Department of Civil Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor A Ahmadi aahmadi@cc iut ac ir AbstractIn recent decades the climate change phenomenon has caused changes in thehydrological cycle of the earth Therefore studying the effects of this phenomenon ondifferent parts of the hydrological cycle and predicting its effects on occurrence of extremephenomena such as drought is necessary In the present study the performance of 24 GCMmodels was analyzed using a multivariable statistical approach including one variablemean standard deviation coefficient of variation Mann Kendall test Kolmogorov Smirnov test and multivariate test of the main component analysis and the superior modelswere selected for the study area Then the large scale monthly time series of precipitationand temperature were extracted for the future period of 2020 2049 from the selectedmodels under three scenarios RCP2 6 RCP4 5 and RCP8 5 The precipitation changescenarios and the temperature change are introduced into the LARS WG downscalingmodel after the interpolation to the meteorological stations coordinates The daily timeseries of precipitation and temperature are obtained for the future period of the consideredstations The results indicate that rainfall will not change significantly and the temperatureof the whole basin will increase by an average of about 1 C The simulated precipitationand temperature values are considered as inputs of the IHACRES hydrologic model Then the monthly time series of discharge are simulated for the future The simulated runoffvalues represent a 15 reduction in average annual runoff and the highest runoff variationswere reported in April In the following the SPI and SRI index respectively formeteorological droughts and hydrological droughts were calculated using simulatedprecipitation and discharge time series for each model and scenario The Bayesianapproach is used to model uncertainty in drought simulation A binomial distribution isconsidered for each class of drought indices according to each model scenario combinationand the final probability distribution for the occurrence of each class is obtained in terms ofthe total model scenario in the form of beta distribution In the following the presentedapproach in this research is applied to the Karkheh basin and its results are presented Theresults show that the occurrence probability of near normal conditions for anymeteorological and hydrological droughts in Karkheh basin is 60 for all studied stations with a variation of 1 3 In addition the relatively humid and moderate drought conditionswith an occurrence probability about 10 after normal conditions have the most probable occurrence Keywords Climate change Multi criteria approach Drought Uncertainty Bayesian approach

آزاده احمدي

اميد بزرگ حداد، محمدحسين گل محمدي