Regional Climatic Variability And Its Influence On Hydrology And Water Resources In Yongding River Basin Of Zhangjiakou

Regional climatic variability and its influence on hydrology and water resourcesbecomes a research hotspot in both domestic and overseas now. Global warming in the pastand it affects on water resources system are solid facts without question. Study on theregional climate change‘s difference and quantify the effects of climate change to the waterresources system is of great significance to us.The paper takes Yongding River basin of Zhangjiakou as the study field. In the thesis,on the basis of hydrographical and meteorological data, the variation features oftemperature，precipitation and runoff such as change trend, abrupt changes and variationperiod are studied by some mathematical methods: Sliding average method, multiplesmoothing (a five-points span), residual mass curve, linear variability, the cumulative filtermethod, the wavelet wave analysis and Mann-Kendall jump. The climate change modeland the method of optimal parameter calibration are expounded. Using the climate changemodel–STAR, the paper gets the results of regional climate simulation under differenttemperature rising situations. The paper studies on the influence of climate change on thesocial water consumption and water resource system such as runoff through simulationrecursive algorithms, multiple regression method and fuzzy optimization neural networkmodel. At last, the paper establishs mathematical model of WRCC (Water ResourcesCarrying Capacity) and gets the WRCC under different climate change scenarios. Theresearch results indicate that:(1)The paper analyzes the changing characteristics of natural annual runoff series oftypical hydrologic stations(Xiangshuipu, Chaigoupu, Shixiali and Qianjiashawa). Thenatural annual runoff series of all the typical station show downtrend. The abrupt changingyear for the stations (Xiangshuipu, Chaigoupu and Shixiali) is1986,1998, and1990. ForQianjiashawa, it hasn’t the abrupt changes. The variation period for the typical hydrologicstation (Xiangshuipu, Chaigoupu, Shixiali and Qianjiashawa) is21a,28a,21a and21a.(2)The annual average temperature was increased significantly in past50years, andthe changing rate of the annual average temperature was0.44℃/10a. At the same time, theprecipitation was decreased slightly, the linear trend coefficient was-3.84/a. Especially forthe summer precipitation, the decreasing trend was significantly. Using Mann-Kendalljump, the paper finds that for the climate station Zhangjiakou, Huailai, Yuxian and thecompositive station the abrupt changing year is1982,1990,1994and1990. For yearprecipitation, the abrupt year is2001,1997,2001and2001. Periodic analysis by using thewavelet transform and wavelet variances analysis finds that for Zhangjiakou, Huailai,Yuxian and the compositive station the variation period is27a.(3)The paper describes the structure, the principle and the usage of STAR (StatisticalRegional Climate Model). On the basis of introduce of STAR, optimal parametercalibration is expounded and the main parameters are determined: blocklength=9,tol_jd=20, tolerance=0.2and no_sim=1000. Especially, the parameter “blocklength”, therecommended value is12, but for the research area in the paper the suitable value is9.(4)The paper use the STAR model to predict the future regional climate under threefuture climate scenarios: high temperature rising situation, the changing rate of the annual average temperature is0.7℃/10a; moderate temperature rising situation, the changingrate of the annual average temperature is0.5℃/10a; low temperature rising situation, thechanging rate of the annual average temperature is0.3℃/10a. Following the climatewarming, there is a decreasing tendency in the regional precipitation, especially in summerprecipitation. The region will become warmer in the future, especially the averageminimum temperature increasing obviously.and the temperature of the winter will growmore obviously than other seasons’temperatures.(5)The paper studies on the influence of climate change on the social waterconsumption. The results show that As precipitation increasing,the supplying agriculturalwater increases and As annual average temperature increasing, the annual averagelife-water quantity for one person increases.(6)The paper studies on the influence of climate change on the quantity of regionalwater resources. The results show that the the quantity of regional water resources showdecreasing tendency under different future climate scenarios in the future. For hightemperature rising situation, the decrease rate of the water resources is230×104m3/a;mo4derate temperature rising situation, the decrease rate of the water resources is160×104m3/a; low temperature rising situation, the decrease rate of the water resources is112×10m3/a.(7)The paper studies on the influence of climate change on the runoff using simulationrecursive algorithms, multiple regression method and fuzzy optimization neural networkmodel. The results show that the effect of simulation for runoff of fuzzy optimizationneural network model is better than other results. For the training data of the fuzzyoptimization neural network model is natural annual runoff under moderate temperaturerising situation, the result of the model for future natural annual runoff is under moderatetemperature rising situation. Using the correction coefficient from the simulate results frommultiple regression method and fuzzy optimization neural network model, the paper getsthe natural annual runoff under different future climate scenarios.(8)For the climate warming has a large impact on the social consumption of water andregional hydrology and water resources, climate change will influence the regionalWRCC(water resources carrying capacity). The paper establishs mathematical model ofWRCC and gets the WRCC under different climate change scenarios. The results show that:As annual average temperature increasing, the WRCC of regional is decreasing. Generallyspeaking, the WRCC of Yongding river basin in Zhangjiakou is under overloading status.