Simulation Study On Multi-source Wind Data Of Low Layer Wind Field At Coastal Areas

The WRF mesoscale numerical model and its three dimensional variational data assimilation system were applied to simulate the low layer wind field at Jiangsu coastal areas.For a start,sparse the multi-source wind fused data, the next,three experiments include control experiment (without assimilation data), sensitive experiment (with assimilation of QuikSCAT) and multi-source wind experiment (with assimilation of a plurality of satellite ground multi-source wind fused data) were conducted, and the comparison between modeled data and situ data were analyzed. The simulation results of the three test schemes for wind elements were evaluated, and the best scheme was applied to the gale process.The results of simulated wind on low layer wind field at this region at April and July in 2008 showed that: the multi-source wind fused data has a high resolution so it needs to be sparse first, best sparse resolution was noted. The effect on the simulation of wind field differed according to the assimilation of the different types of wind data, compared to the FNL forecast directly, assimilation of wind data improves initial fields; according to the hourly export data form the analysis fields, the assimilation experiment was inferior to the control experiment,but a limit to wind direction. After investigating the effect of the sensitive experiment and multi-source wind experiment,the multi-source wind experiment were chosen.Based on the understanding of the assimilation effect of multi-source data simulation,one typhoon gale occurred at July 29-31, 2008, and the other cold wave occurred at December 21-22, 2008, the two gales were conducted by the multi-source wind experiment respectively. For the simulation study of the typhoon "fenghuang", the test results showed that the multi-source wind experiment successfully simulated the development process of typhoon,at Jiangsu coastal areas. However,the simulated precipitation was not accurate. For the simulation study of cold wave, the mode accurately simulated the distribution of wind speed and the movement of the strong wind, and the simulated maximum values slightly less than the actual measurement. The results of the two simulation test results were problematic in the time evolution of wind speed,and the simulation results were ahead of the actual observations.