热带气象学报2024，Vol.40Issue(3)：397-410,14.DOI:10.16032/j.issn.1004-4965.2024.036
相似台风"纳沙"和"海鸥"在雷州半岛产生的降雨差异及其可能机制研究
Rainfall Difference on Leizhou Peninsula Between Similar Typhoons Nesat and Kalmaegi and Their Possible Mechanisms
摘要
Abstract
This study examined the differences in rainfall characteristics and possible mechanisms behind such differences for two typhoons,Nesat(1117)and Kalmaegi(1415),which followed similar paths over the Leizhou Peninsula(LP).Utilizing data from conventional meteorological stations,regional automated weather stations,radar observations,and ERA5 reanalysis,the present study analyzed the distinct patterns of rainfall induced by these typhoons.The results showed that the total rainfall and maximum rainfall of Typhoon Nesat were 1.5 and 2.4 times higher than those of Typhoon Kalmaegi,respectively.The total rainfall of Typhoon Nesat included both rainfall from the typhoon circulation and the typhoon trough,while Typhoon Kalmaegi only had rainfall from the typhoon circulation.The major reasons for such differences were as follows:after the landfall of Typhoon Nesat,the South Asian High and the Subtropical High broke into the eastern and western parts,resulting in a strong high-level divergence over the LP area,and the southwesterly and southeasterly currents converged into the southerly at the low level.Meanwhile,the frontal area facilitated the intrusion of cold air from 850 hPa and below into the typhoon trough of Typhoon Nesat,and the baroclinic effect intensified convection.After the weakening of the typhoon circulation,the low-level convergence in the LP area strengthened again,which in turn created favorable conditions for rainfall and led to the intensification of rainfall in the typhoon trough.By contrast,after Typhoon Kalmaegi made landfall,the LP region was affected by the enhancement and southward movement of the South Asian High and the Subtropical High,and the low-level convergence in the LP area quickly changed to divergence after the weakening of the typhoon circulation.The downward airflow inhibited the development of convection,resulting in minimal rainfall formation in the typhoon trough.Moreover,it was also found that the topography of the LP affected the location of typhoon rainfall centers,which were usually identified on the windward slopes southeast of the LP's three peaks.These results may facilitate the forecasting and diagnosis of typhoon rainfall affecting the LP.关键词
雷州半岛/相似台风/降雨差异/影响机制/台风环流Key words
Leizhou Peninsula/similar typhoon/rainfall difference/impact mechanism/typhoon circulation分类
天文与地球科学引用本文复制引用
吴德平,张琼雄,钟谢非,涂石飞,宋清涛..相似台风"纳沙"和"海鸥"在雷州半岛产生的降雨差异及其可能机制研究[J].热带气象学报,2024,40(3):397-410,14.基金项目
国家自然科学基金重大项目(72293604) （72293604）
广东省气象局科学技术研究项目(GRMC2020OM39) （GRMC2020OM39）
气象风险与保险联合开放实验室开放基金项目(2023F005) （2023F005）
广东海洋大学科研启动经费资助项目(060302032304)共同资助 （060302032304）
