Abstract:
The SWV (southwest vortex) is known for its strong ability to cause disasters and extensive influence, making it crucial to understand its rainfall mechanisms and climate characteristics. The objective identification algorithm based on grid data is one of the important basic contents in SWV research. The local disturbance caused by high spatial resolution grid data and the influence of topography on the integrity of SWV circulation are the main reasons for the low identification accuracy of existing algorithms. In this paper, a new objective identification method for SWV based on a 700-hPa wind field is proposed. This method can overcome the adverse effects of local disturbances and terrain occlusion without pre-processing (e.g., smoothing) of identification data and significantly improve the accuracy of identifying SWV centers. The improved tracking algorithm can recognize new SWVs and prevent wrong connections between old and new SWV centers, resulting in increased objective SWV tracking. Evaluation results show that the average identification hit rate, missing report rate, and false alarm rate of the new method are 85.71%, 14.29%, and 11.7%, respectively. In the area east of 104°E, where terrain effects are not intense, the identification hit rate is more than 90%, with the missing report and false alarm rates being lower than 10%. This improved recognition accuracy and higher computational efficiency make the new method highly suitable for scientific research and professional applications.