Abstract:

Weather radar plays an important role in meteorological services such as nowcast and quantitative precipitation estimation due to its high spatiotemporal resolution, large detection range and wide network coverage. Radar echoes included the precipitation, insect and bird echoes, but non-meteorological echoes such as insect and bird echoes were usually removed as noise in the current meteorological operations, resulting in wasted information. In this paper, the authors constructed the identification algorithm of precipitation, insect and bird echoes based on fuzzy logic algorithm using the dual polarization weather radar data from Lianyungang, evaluated the identification effect of the algorithm, and analyzed the identification results of precipitation echoes, insect echoes, bird echoes as well as their mixed scenarios, aiming to provide a foundation for aerial biological monitoring. The results showed as follows: (1) the accuracy (ACC) of precipitation echoes and biological echoes were improved from 0.90 and 0.88 to 0.95 and 0.94, respectively, after adding post-processing to the identification results of the fuzzy logic algorithm. (2) In the results of classifying biological echoes into insect echoes and bird echoes by fuzzy logic algorithm, the ACC was 0.96, the true positive rate (TPR) was 0.94, the true negative rate (TNR) was 0.98, and the heidke skill score (HSS) achieved 0.92. The radar echo identification algorithm constructed in this paper is able to identify precipitation echoes, insect echoes, bird echoes and their differences very well.

Key words: Fuzzy logic, Dual polarization weather radar, Echoes identification, Precipitation echoes, Insect and bird echoes