海洋科学2024，Vol.48Issue(12)：27-43,17.DOI:10.11759/hykx20240403002
热带西北太平洋中尺度涡要素研究
Study of mesoscale eddy features in the tropical Northwest Pacific Ocean
摘要
Abstract
Mesoscale eddies in the tropical Northwest Pacific play a significant role in shaping the tempera-ture-salinity structure of seawater and influencing marine fishery resources.To explore the relationship between mesoscale eddies and changes in the environmental flow field,satellite altimeter data from 1993 to 2021 were ana-lyzed.A geometric feature-based method was used to identify and track mesoscale eddies in the region.The study area(2°N-20°N)was divided into three regions(A,B,and C)from north to south,with the axes of the North Equatorial Current(NEC)and North Equatorial Countercurrent(NECC)serving as dividing lines.The spatiotem-poral distribution characteristics of mesoscale eddy features in each region were then examined.The results show that mesoscale eddies within the study area are predominantly short-period cyclonic eddies with a period of≤28 days,making up 92.18%of the total eddy population.Eddies with radii ranging from 30 to 100 km and amplitudes between 1 and 3 cm account for 73.66%and 75.56%,respectively.The correlation coefficient between the mean radius and mean amplitude of mesoscale eddies is 0.65,indicating a significant positive correlation.Furthermore,the number,lifecycle,amplitude,and propagation distance of mesoscale eddies in region A surpass those in regions B and C.In regions B and C,the formation of anticyclonic eddies occurs approximately 4 months and 1 month ahead of the Oceanic Niño Index,respectively,with correlation coefficients of-0.35 and-0.53.A strong correlation is observed when the flow field intensities of the NEC and NECC change simultaneously.In contrast,no significant correlation is found in region A.These findings suggest that the interannual variability of mesoscale eddy abun-dance,NEC,NECC,and eddy kinetic energy in regions B and C is significantly influenced by the El Niño-Southern Oscillation(ENSO).During El Niño events,both the NEC and NECC strengthen,leading to decreases in sea sur-face temperature and sea surface height,while wind stress and mean ocean kinetic energy increase.Eddy kinetic energy is further amplified through the absorption of energy from the flow field.In contrast,during La Niña events,eddy kinetic energy returns to baseline levels.As a result,ENSO exerts a substantial influence on upper ocean dy-namics in the tropical Northwest Pacific,with the periodic fluctuations in upper oceanic flow fields serving as a major driver of interannual variability in mesoscale eddies in this region.关键词
热带西北太平洋/中尺度涡/时空特征/ENSO/涡动动能Key words
tropical Northwest Pacific/mesoscale eddy/spatiotemporal characteristics/ENSO/eddy kinetic energy分类
海洋科学引用本文复制引用
苏日昇,魏永亮,唐泽艳,袁新哲..热带西北太平洋中尺度涡要素研究[J].海洋科学,2024,48(12):27-43,17.基金项目
国家自然科学基金项目(41976174,41606196) （41976174,41606196）
农业农村部全球渔业资源调查监测评估(公海渔业资源综合科学调查)项目(D-8025-23-1002)National Natural Science Foundation of China,Nos.41976174,41606196 （公海渔业资源综合科学调查）
Project on the Survey and Monitor-Evaluation of Global Fishery Resources sponsored by Ministry of Agriculture and Rural Affairs,No.D-8025-23-1002 （）
