Nowcasting typhoon circulation using Doppler radar - the ground-based VTD (GBVTD) technique

Recently, Lee et al. (1993) proposed a Velocity Track Display (VTD) technique to extract primary hurrican circulations using data from a single airborne Doppler radar with just one penetration through the hurricane center. The motivation of this study is to propose a Ground-Based VTD (GBVTD) technique which uses the ground-based Doppler radar data to extract the primary circulations of a hurricane in near real-time. In this preliminary analysis, we have shown that the GBVTD technique is able to extract the primary circulation of a typhoon using data from a single ground-based Doppler radar in real time. The GBVTD technique can not only resolve the tangential velocities of a typhoon but also can resolve the mean radial velocity structure. With the real-time GBVTD products, it is possible to continuously monitor the typhoon structure with a ground-based Doppler radar. The ability to track the mean inflow/ outflow structure can be a valuable piece of information toward forecasting the typhoon intensity.