2021年10月南海北部上层细结构对台风“圆规”的响应分析  

Analysis of upper ocean fine structure response to typhoon Kompasu in the northern Nanhai Sea in October 2021

作　　者：李佳昊 王桂华 王喜冬 陈志强 LI Jiahao;WANG Guihua;WANG Xidong;CHEN Zhiqiang(College of Oceanography,Hohai University,Nanjing 210098,China;Department of Atmospheric and Oceanic Sciences,Fudan University,Shanghai 200082,China)

机构地区：[1]河海大学海洋学院,江苏南京210098 [2]复旦大学大气与海洋科学系,上海200082

出　　处：《海洋通报》2022年第4期411-417,共7页Marine Science Bulletin

基　　金：国家重点研发计划重点专项(2019YFC1510100)。

摘　　要：基于水下滑翔机观测资料,分析了2021年10月南海北部上层海洋细结构强度及类型对台风“圆规”的响应特征。在细结构强度响应方面,受台风“圆规”影响,次表层盐度升高,温度降低,最大降温幅度可达3℃,温跃层中上部细结构显著增强。“圆规”影响期间温度、盐度细结构强度最大值深度均约为50 dbar,温度、盐度细结构强度最大值在台风过境后分别移至温跃层上部和中部。结果表明,“圆规”通过加强海洋上层混合促进了“共变型”细结构的生成。台风中心过境时,Ekman抽吸引起的上升流对温跃层产生了水团入侵的效果,从而使“侵入型”细结构瞬时增多;台风过境后,“侵入型”细结构强度迅速衰减,“共变型”细结构在温跃层内减弱,而在200-400 dbar深度范围内继续加强,表示该层海水混合继续加强。由此表明,南海北部上层细结构的强度和类型变化对台风“圆规”响应显著。Based on the in-situ data from an underwater glider deployed in the Northern Nanhai Sea(NSCS),the strength and characteristic response of fine structure to the typhoon Kompasu in October 2021 are investigated.In the aspect of strength response,after the typhoon passing,the temperature and salinity in the subsurface decreased and increased separately,the maximum decreased temperature amplitude is about 3℃.The fine structure was significantly strengthened below the mixed layer,and the enhanced part was mainly concentrated in the middle and upper thermocline layer.During the effect of Kompasu,the maximum depth of the strength of temperature and salinity fine structure were both at about 50 dbar.Further,the maximum depth of strength of temperature and salinity fine structure respectively moved to the top and middle of thermoclines after the Kompasu passing.The result shows that,the Kompasu promoted the formation of co-variant fine structure by strengthening the mixing in the upper layer.When the typhoon center passed through,the Ekman pumping induced upwelling has an effect on thermocline such as through water mass invasion,which leads to the rapid increase of intrusive fine structure.After the passage of Kompasu,the intrusive fine structure recovered rapidly,and the co-variant fine structure weakened in the thermocline but continued to strengthen at the range of 200-400 dbar,which promoted the subsurface mixing.The results indicate that the strength and type of upper ocean fine structure are significantly responsive to typhoon Kompasu in the northern Nanhai Sea.

关 键 词：细结构 台风 水下滑翔机 南海 

分 类 号：P732.6[天文地球—海洋科学] P731