全球气候变化背景下,极端水文气象事件发生的频率和强度都受到了直接影响,研究气候变化对极端水文气象事件的影响对防灾减灾和工程设计等至关重要。采用了联合国政府间气候变化专门委员会(IPCC)第四次评估报告中给出的A1B、A2和B1三种温室气体排放情景,选用大气环流模式Had-CM3,利用随机天气发生器LARS-WG生成逐日气象资料,结合P-Ⅲ型曲线和线性矩方法分析计算了钱塘江流域21世纪中叶的设计暴雨情况。结果表明:LARS-WG天气发生器在钱塘江流域有较好的模拟效果;在A1B和B1情景下,钱塘江流域各站点不同重现期下的设计暴雨值基本呈增大趋势,其中A1B情景下杭州站百年一遇的设计暴雨值为209.14mm,比基准期增大11.0%。
Climate change affects the frequency and intensity of extreme hydrological events, e.g. extreme storm in a very direct way. Studying these effects caused by climate change will provide great support for disaster mitigation and engineering design. This paper ap- plied the LARS-WG weather generator to simulate synthetic weather data under the AIB, A2 and B1 emission scenarios from Intergovern- mental Panel on Climate Change (IPCC) using the results of General Circulation Model HadCM3. Based on the L-moments approach, de- sign storms of different return periods were calculated for the Qiantangjiang River Basin in 2055s using the P-III distribution function. The final results show that the LARS-WG weather generator has good capability in simulating synthetic weather data in the Qiantang River Basin and the maximum bias between observed and simulated design storms of 200a return period is 8.52%, occurring at the Shengxian Station. The design storms of different return periods tend to increase under the A1B and B1 scenarios, while decline under the A2 scenar- ios at the most stations. And design storm of 100a return period at the Hangzhou Station will be 209.14mm under the AIB scenarios, l 1 percent larger than that in the baseline period. The biggest increase and decrease of the design storm of 100a return period is 39.54% and 42.79%, occurring at the Jinhua Station under the B1 scenarios and Tianmushan station under the A2 scenarios respectively.