利用WRF(V3.3.1)模式及其同化系统,根据不同地面观测要素同化对模式侧边界条件和初始条件引起的改变设计数值模拟方案,详细分析了WRF模式初始和侧边界条件的改变对四川盆地东部强降水模拟的敏感性影响.结果显示,WRF模式对初始和侧边界条件改变的敏感度均较明显,对地面温度变化的敏感度要高于对地面风场变化的敏感度.相对湿度场、风场和垂直速度场,均体现为高层比低层更敏感,而温度场则体现为低层比高层更敏感.在模拟时段内,侧边界条件的改变对模拟结果带来的不确定性影响随时间的增加逐渐增加,初始条件改变对模拟结果带来的不确定性影响随时间增加而逐渐减小.%By the use of the WRF (V3. 3.1) model and the assimilation system, experiments are carried out with the numerical simulation scheme designed on the different boundary and initial conditions with the different assimilated element observation. The sensitivity impact analysis of the WRF model boundary conditions on the simulation of the heavy rainfall happened in the eastern Sichuan Basin is discussed. The results show that the WRF model is sensitive to the change of initial and boundary conditions. The change caused by the assimilation of ground temperature is more sensitive than that caused by the assimilation of the ground wind field. The sensitivities to the upper-level relative humidity, wind, and vertical velocity are bigger than those to the lower-level. During test, the sensitivities to lower temperature and unstable energy are bigger than those to the upper. The sensitivities caused by boundary conditions increase with time. The sensitivities caused by initial conditions decrease with time.
展开▼
