Numerical Simulation and Evaluation of a New Hydrological Model Coupled with GRAPES  

作　　者：郑子彦 张万昌 徐精文 赵琳娜 陈静 严中伟 

机构地区：[1]Key Laboratory of Regional Climate-Environment Research for East Asia,Institute of Atmospheric Physics,Chinese Academy of Sciences [2]University of the Chinese Academy of Sciences [3]Center for Earth Observation and Digital Earth,Chinese Academy of Sciences [4]College of Resources and Environment,Sichuan Agricultural University [5]National Meteorological Center,China Meteorological Administration

出　　处：《Acta meteorologica Sinica》2012年第5期653-663,共11页

基　　金：Supported by the National Basic Research and Development (973) Program of China (2010CB951404);National Natural Science Foundation of China (40971024);China Meteorological Administration Special Public Welfare Research Fund (GYHY200706001 and GYHY200906007)

摘　　要：Hydrological processes exert enormous influences on the land surface water and energy balance, and have a close relationship with human society. We have developed a new hydrological runoff parameteriza- tion called XXT to improve the performance of a coupled land surface-atmosphere modeling system. The XXT parameterization, which is based upon the Xinanjiang hydrological model and TOPMODEL, includes an optimized function of runoff calculation with a new soil moisture storage capacity distribution curve （SMSCC）. We then couple XXT with the Global/RegionM Assimilation Prediction System （GRAPES） and compare it to GRAPES coupled with a simple water balance model （SWB）. For the model evaluation and comparison, we perform 72-h online simulations using GRAPES-XXT and GRAPES-SWB during two torrential events in August 2007 and July 2008, respectively. The results show that GRAPES can reproduce the rainfall distribution and intensity fairly well in both cases. Differences in the representation of feedback processes between surface hydrology and the atmosphere result in differences in the distributions and amounts of precipitation simulated by GRAPES-XXT and GRAPES-SWB. The runoff simulations are greatly improved by the use of XXT in place of SWB, particularly with respect to the distribution and amount of runoff. The average runoff depth is nearly doubled in the rainbelt area, and unreasonable runoff distributions simulated by GRAPES-SWB are made more realistic by the introduction of XXT. Differences in surface soil moisture between GRAPES-XXT and GRAPES-SWB show that the XXT model changes infiltration and increases surface runoff. We also evaluate river flood discharge in the Yishu River basin. The peak values of flood discharge calculated from the output of GRAPES-XXT agree more closely with observations than those calculated from the output of GRAPES-SWB.Hydrological processes exert enormous influences on the land surface water and energy balance, and have a close relationship with human society. We have developed a new hydrological runoff parameteriza- tion called XXT to improve the performance of a coupled land surface-atmosphere modeling system. The XXT parameterization, which is based upon the Xinanjiang hydrological model and TOPMODEL, includes an optimized function of runoff calculation with a new soil moisture storage capacity distribution curve （SMSCC）. We then couple XXT with the Global/RegionM Assimilation Prediction System （GRAPES） and compare it to GRAPES coupled with a simple water balance model （SWB）. For the model evaluation and comparison, we perform 72-h online simulations using GRAPES-XXT and GRAPES-SWB during two torrential events in August 2007 and July 2008, respectively. The results show that GRAPES can reproduce the rainfall distribution and intensity fairly well in both cases. Differences in the representation of feedback processes between surface hydrology and the atmosphere result in differences in the distributions and amounts of precipitation simulated by GRAPES-XXT and GRAPES-SWB. The runoff simulations are greatly improved by the use of XXT in place of SWB, particularly with respect to the distribution and amount of runoff. The average runoff depth is nearly doubled in the rainbelt area, and unreasonable runoff distributions simulated by GRAPES-SWB are made more realistic by the introduction of XXT. Differences in surface soil moisture between GRAPES-XXT and GRAPES-SWB show that the XXT model changes infiltration and increases surface runoff. We also evaluate river flood discharge in the Yishu River basin. The peak values of flood discharge calculated from the output of GRAPES-XXT agree more closely with observations than those calculated from the output of GRAPES-SWB.

关 键 词：coupled model GRAPES XXT 

分 类 号：P334[天文地球—水文科学]