关键词: C波段雷达, 对流频数, 秦岭, 大巴山区, 对比

Abstract: Based on the radar data in Hanzhong from June to August during 2013-2017 and the convective zone on constant altitude plan position indicator by using discrimination method, the characteristics of convective activities were analyzed during the warm season in and around Hanzhong areas. The results show that the high frequency areas of convective activities were mainly located in the Daba mountains, the southeastern foothills of the Qinling mountains and the transitional zone of the eastern QinlingDaba mountains around Hanzhong city, the highest convective frequencies and the widest areas were in the Daba mountains, followed by the southeastern foot of the Qinling mountains and the transitional zone of the Qinling and Daba mountains, and convective frequency was least in the western part of the Hanzhong basin. The convective activity was most in July and least in June, and convective frequency and convective areas showed obvious diurnal variation. The locations of convective high frequencies areas were highly correlated with mountainous terrain features. The high convection frequencies areas in the Daba mountains nearly coincided with terrain heights, while the high value areas in the southeastern foothills of the Qinling mountains were located on mountain slopes. The convection extension height was mostly below 7 km, with the highest proportion at a height of 4 to 5 km. Based on the reanalysis data, it was found that the convective instability energy maintained a high value center in the eastern part of the Sichuan basin in July and August, which was very close to the Daba mountains in the north of it, and it may be one of the contributing factors to the persistence of the local high convective region.

Key words: Key words: C-band radar, convection frequency, the Qinling mountains, the Daba mountains area, comparison