Abstract:Using the realtime Doppler weather radar, boundary layer wind profiler radar, and automatic weather station data, the characteristic structure evolution in the 4th landing of supertyphoon Ramasun on the Guangxi coastal is studied. The results show that the typhoon eye area had characteristics of low atmospheric pressure, weak wind speed, dry and warm air, in which atmospheric pressure showed funnelshaped changes; the typhoon eye area maintained a round shape during typhoon landing, with a radius of 30 km, a typical strong typhoon structure. In addition, the large value area of the radial velocity in radar exhibited an asymmetrical feature with the right quadrant larger than the left quadrant. The error of surface measurements is only 5.4 m/s; the horizontal wind field of wind profiler radar can reflect the vertical structure accurately and intuitively in different parts of the typhoon. Wind direction had experienced a “northeasteastsoutheastsouth” change process, and the overall characteristics of wind speed increased first and then decreased. Moreover, the vertical speed, atmospheric refractive index,structure constant (C2n) can well reflect the variation of typhoon structure, typhoon clouds and airflow; wind direction was consistent in two types of weather radar wind field products, but in VWP products wind speed was smaller than that from wind profiler radar. When there are invalid data in VWP products, wind profiler radar products can be used as complementary.