摘要
利用AVISO提供的中尺度涡数据集,对1993-2019年间安达曼海中尺度涡的涡旋特征、运动规律及其季节变化机制进行统计分析。结果显示,27年间安达曼海共出现中尺度涡328个,其中反气旋涡(171个)多于气旋涡(157个),主要分布在中西部盆地深水区。涡旋平均寿命为46.4d,平均半径为111.8 km,平均振幅为4.7 cm,平均最大转速为24.8 cm/s,平均移动速度为15.0 cm/s,反气旋涡的平均半径、振幅和转速均大于气旋涡,而移动速度小于气旋涡。涡旋的半径、振幅和最大转速在其生命周期中都经历了先增大后减小的过程,移动速度则先减小后增大。在季节变化方面,反气旋涡和气旋涡性质冬夏对比呈现“跷跷板”现象,即夏季气旋涡比反气旋涡更多更强更大,冬季则反气旋涡更多更强更大;涡旋分布位置,夏季从北向南呈“气旋-反气旋-气旋”的极性反转交替分布,冬季则与之相反。动力机制分析显示,背景流场涡度可能影响安达曼海涡旋极性交替分布,正(负)涡度背景流利于气旋(反气旋)涡存在。涡旋能量变化机制显示,风强迫是安达曼海涡旋主要能量来源,风场能量输入与涡旋动能的季节变化吻合。
Using mesoscale eddy trajectory product from 1993 to 2019 provided by the AVISO,this study analyzes the climatology characteristics and seasonal variations of mesoscale eddies in the Andaman Sea(AS).The results show that a total of 328 mesoscale eddies were generated in the AS during the past 27 years,of which anticyclonic eddies(AEs)(171)were more than cyclonic eddies(CEs)(157).The eddies are mainly distributed in the deep waters of the central and western basin of the AS.The average life span of total eddies is 46.4 days,with average eddy radius of 111.8 km,average amplitude of 4.7 cm,rotating and propagating speeds of 24.8 cm/s and 15.0 cm/s,respectively.The AEs have large radius,amplitude,and rotating speed than CEs,but smaller propagating speed.During the eddy life,the composite radius,amplitude,and rotating speed of eddies all increase in the generation stage and then decrease in dissipation stage,while the eddy propagation speed has opposite trend.For the seasonal variation,the comparison of AEs to CEs shows seesaw phenomena in winter and summer,CEs are stronger and larger than AEs in summer,but weaker and smaller in winter.The distribution of AEs and CEs also shows seasonal polarity reversal,a‘CEs-AEs-CEs’pattern from north to south in summer,but a reversed‘AEs-CEs-AEs’pattern in winter.Dynamic analysis showed that the vorticity of background current may affect the alternating distribution pattern of mesoscale eddies in the AS,in which positive(negative)vorticity favors CEs(AEs).The energy analysis shows that wind forcing is dominant in the eddy kinetic energy(EKE)variation,and the seasonal wind work is coherent to the EKE variation in the AS.
作者
林圳涛
谢玲玲
黄润琪
白鹏
Lin Zhentao;Xie Lingling;Huang Runqi;Bai Peng(Laboratory of Coastal Ocean Variation and Disaster Prediction,College of Oceanology and Meteorology,Guangdong Ocean University,Zhanjiang 524088,China;Guangdong Key Laboratory of Climate,Resource and Environment in Continental Shelf Sea and Deep Ocean,Zhanjiang 524088,China;Key Laboratory of Space Ocean Remote Sensing and Application,Ministry of Natural Resources,Beijing 100081,China)
出处
《海洋学报》
CAS
CSCD
北大核心
2023年第4期1-16,共16页
基金
国家自然科学基金(42276019,41776034)
广东省高等学校创新团队项目(2019KCXTF021)
广东省冲一流专项资金项目(231419012,231819002)
广东海洋大学科学博士启动基金(R18001)。
关键词
安达曼海
中尺度涡
统计特征
季节变化
极性反转
Andaman Sea
mesoscale eddy
statistical features
seasonal variation
polarity distribution reversal
作者简介
林圳涛(1998-),男,广东省揭阳市人,主要从事物理海洋学研究。E-mail:1397454768@qq.com;通信作者:谢玲玲(1983-),女,教授,博士,主要从事物理海洋学研究。E-mail:xiell@gdou.edu.cn。
