NCAR湖泊子模型对东太湖湖-气交换的离线模拟及评估

摘要

Accurate lake-air land surface process is important for simulation and prediction of weather and cli-mate. Seasonal changes of water plant characteristics in the east Taihu Lake were analyzed to adjust the extinction coefficient, eddy diffusion coefficient and roughness length in the NCAR lake sub-model;the observed data of east Lake Taihu BFG No. 1 platform on January, April, July, October of 2012 was used to drive offline lake model and evaluate the NCAR lake sub-model on sensible heat flux, latent heat flux, lake surface temperature and friction ve-locity in different seasons. The results show that, the simulation results using turned parameters have been im-proved in four seasons, especially, the root mean square error ( RMSE) of simulated and observed sensible heat flux reduces from 12. 37 W·m-2 to 9. 7 W·m-2 , the RMSE of latent heat flux reduces from 50. 19 W·m-2 to 31. 48 W·m-2 , the RMSE of lake surface temperature decreases from 1. 03 ℃ to 0. 62 ℃, and the RMSE of fric-tion velocity decreases from 0. 23 m·s-1 to 0. 10 m·s-1.%准确的湖泊-大气陆面过程方案对天气气候的模拟和预测十分重要。通过对内陆浅水湖泊太湖东部不同季节水生植物特征进行分析,调整了NCAR湖泊子模型的消光系数、湍流扩散系数及粗糙度等参数；利用东太湖避风港1号观测平台2012年1、4、7、10月的观测数据驱动离线湖模式,评估了NCAR湖泊子模型对不同季节感热通量、潜热通量、湖表温度及摩擦速度的模拟性能。结果表明,参数调整后的NCAR湖泊子模型的模拟结果在4个季节都有了不同程度的改善,其中感热通量模拟值与观测值的均方根误差由12．37 W·m－2减小到9．7 W·m－2,潜热通量由50．19 W·m－2减小到31．48 W·m－2,湖表温度由1．03℃减小到0．62℃,摩擦速度由0．23 m·s－1到0．10 m·s－1。