应用新一代中尺度预报模式WRF模式及其3DVar同化系统,针对江苏地区2009年6月14日飑线过程进行了多普勒雷达资料的同化试验研究,在对雷达资料进行严格质量控制的基础上,设计一系列尺度化因子优化调整及同化频率的敏感性试验。试验结果表...应用新一代中尺度预报模式WRF模式及其3DVar同化系统,针对江苏地区2009年6月14日飑线过程进行了多普勒雷达资料的同化试验研究,在对雷达资料进行严格质量控制的基础上,设计一系列尺度化因子优化调整及同化频率的敏感性试验。试验结果表明:同化后初始场得到不同程度改善,适当的尺度化因子设定,能够有效改进对模式初始场中700 h Pa风场和850 h Pa温度场以及组合反射率因子等要素的分析,进而改善短时降水预报和风暴的垂直结构配置;并且同化频率越高,对初始场的组合反射率因子分布与观测更为接近,短时降水预报越准确。展开更多
Initialization and initial imbalance problem were discussed in the context of a three-dimensional variational data assimilation system of the new generation"Weather Research and Forecasting Model". Several o...Initialization and initial imbalance problem were discussed in the context of a three-dimensional variational data assimilation system of the new generation"Weather Research and Forecasting Model". Several options of digital filter initialization have been tested with a rain storm case. It is shown that digital filter initialization, especially diabatic digital filter initialization and twice digital filter initialization, have effectively removed spurious high frequency noise from initial data for numerical weather prediction and produced balanced initial conditions. For six consecutive intermittent data assimilation cycles covering a 3-day period, mean initialization increments and impact on forecast variables are studied. DFI has been demonstrated to provide better adjustment of the hydrometeors and vertical velocity, reduced spin-up time, and improved forecast variables quantity.展开更多
文摘应用新一代中尺度预报模式WRF模式及其3DVar同化系统,针对江苏地区2009年6月14日飑线过程进行了多普勒雷达资料的同化试验研究,在对雷达资料进行严格质量控制的基础上,设计一系列尺度化因子优化调整及同化频率的敏感性试验。试验结果表明:同化后初始场得到不同程度改善,适当的尺度化因子设定,能够有效改进对模式初始场中700 h Pa风场和850 h Pa温度场以及组合反射率因子等要素的分析,进而改善短时降水预报和风暴的垂直结构配置;并且同化频率越高,对初始场的组合反射率因子分布与观测更为接近,短时降水预报越准确。
基金National Natural Science Foundation of China (40675020)
文摘Initialization and initial imbalance problem were discussed in the context of a three-dimensional variational data assimilation system of the new generation"Weather Research and Forecasting Model". Several options of digital filter initialization have been tested with a rain storm case. It is shown that digital filter initialization, especially diabatic digital filter initialization and twice digital filter initialization, have effectively removed spurious high frequency noise from initial data for numerical weather prediction and produced balanced initial conditions. For six consecutive intermittent data assimilation cycles covering a 3-day period, mean initialization increments and impact on forecast variables are studied. DFI has been demonstrated to provide better adjustment of the hydrometeors and vertical velocity, reduced spin-up time, and improved forecast variables quantity.
