基于PRECIS模式对珠江流域降水的模拟与分析

Simulation and analysis of future precipitation along the Pearl River Basin based on PRECIS model

该文使用区域气候模式PRECIS的A1B情景,模拟1961-1990年珠江流域降水平均值、区域分布和概率分布,并对订正方法的效果进行了检验,检验结果表明PRECIS模式模拟的结果与观测值接近,对模拟结果进行概率订正后模拟结果得到了改善。在模式效果可信的基础上,对珠江流域2021-2050年降水量进行了模拟和分析,模拟结果表明未来时段珠江流域的降水总体稍微增加,珠江流域全年下游降水增多,上游降水减少,降水的波动性增加,未来降水量趋于两极化,可能导致极端多雨和极端少雨事件的增加,更易导致干旱和洪涝的发生;未来珠江流域降水在时空分布上将更加不均匀,即冬季和春季南部沿海降水增多,北部降水减少;夏季和秋季北部降水增多,南部降水减少。

The mean,regional distribution and probability distribution of precipitation in the Pearl River Basin from 1961 to 1990 were simulated by using the A1 B scenario of PRECIS model.The results show that the simulation results of PRECIS model are close to the observed values,and the simulation results are improved after the probabilistic correction of the simulation results.On the basis of the credible model,the precipitation of the Pearl River Basin from 2021 to 2050 were simulated and analyzed.The simulation results show that the precipitation of the Pearl River Basin increases slightly in the future.the volatility of precipitation increases,precipitation in the Pearl River Basin increased in the downstream and precipitation decreased in the upstream,and the future precipitation tends to be polarized,it may lead to the increase of extreme rainy and extreme rainless events,which is more likely to lead to drought and flooding;in the future,precipitation in the Pearl River basin will be more uneven in time and space,that is,precipitation in the southern coast in winter and spring increases,precipitation in the north decreases;during the summer and autumn,the precipitation increased in the north and precipitation decreased in the south.