Cases Study On Doppler Radar And Satellite Cloud Motion Wind Data Assimilation

Herein main purpose is study on CINRAD (Chinese Next Generation Weather Radar) and satellite data assimilation in the application of the examples analysis. Based on data of NCEP, CINRAD net, FY-2D meteorological satellite, remote sensing observations assimilaton are studied and analyzed with diagnosis, numerical simulation and theories.By means of ARPS-3DVar and ADAS (ARPS Data Analysis/Assimilation System), CINRAD observations are assimilated only with NCEP reanalysis data for the forecast of a rainstorm occurred in July 2009, and 2010 No.3 Typhoon Chanthu. Results show that meteorological element fields are improved observably by assimilation experiments. And more assimilation times lead to better wind field, water vapor field and the like, which are closer to observations insitu, especially for water vapor field, leading to the fact that short-time precipitation simulation is also closer to observations. Thereinto radar radial velocity data improve mostly upon initial wind field with obvious mesoscale structures. The corresponding assimilation experiment improves effectively on water vapor field, causing clear water vapor center, just in actual rainstorm center. After one hour integral, reflectivity data's role on wind field is clear and mesoscale structure can be simulated continually, similarly with radial velocity data assimilation experiment. For radial velocity data, followed with the beginning of one hour integral, radial velocity data assimilation experiment appears water vapor centers with great values, wherever these are not concerned with actual condition. It is showed that reflectivity data assimilation experiments are briefly marked on improving forecast fields than that of radial velocity.Typhoon Morakot is a case to study FY-2D satellite observations indirect assimilation experiments. CMW (Cloud Motion Wind) data from TCFM Tracking Cloud with Combined Fourier Phase Analysis and Maximum Correlation) method data are assimilated into numerical model. CMW data from TCFM method assimilation experiment adjusts effectively on initial vertical wind field, resulting intense ascent motions at eyewall of the typhoon, whatever in lower, middle or upper levels, lasting for hours. These ascent motions are just at the center of modeled water vapor fields, which leading to severe storm and rainfall at eyewall of typhoon Morakot. It is presented that indirect assimilation experiment of CMW data from TCFM method improves effectively not only on vertical velocity field but for precipitation.