Persistent mixing bursts in the equatorial Pacific thermocline induced by persistent equatorial waves
作者机构:School of Mathematics and PhysicsQingdao University of Science and TechnologyQingdao 266100China Key Laboratory of Ocean Circulation and WavesInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laoshan LaboratoryQingdao 266237China
出 版 物:《Journal of Oceanology and Limnology》 (海洋湖沼学报(英文))
年 卷 期:2024年第42卷第2期
页 面:492-510页
核心收录:
学科分类:0710[理学-生物学] 07[理学] 0707[理学-海洋科学]
基 金:Supported by the National Natural Science Foundation of China(NSFC)(No.41730534) the Laoshan Laboratory Science and Technology Innovation Program(No.LSKJ 202202502) the NSFC(Nos.41976012,42090044) the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB42000000)
主 题:interior turbulent mixing layer(ITML) weakly sheared layer(WSL) Equatorial Undercurrent(EUC)core occurrence probability seasonality
摘 要:A recent study by Liu et al.(2020)suggested that due to the saturation of equatorially trapped planetary waves with different dynamical types,temporal periods,meridional and baroclinic modes,complex layer structures of vertical velocity shear and hence turbulent mixing could frequently occur in the thermocline of the eastern equatorial *** investigated the occurrence of the interior turbulent mixing as indicated by shear instabilities,above the Equatorial Undercurrent(EUC)core at three equatorial sites along 140°W,170°W,and 165°E,respectively,based mainly on data from the Tropical Atmosphere and Ocean(TAO)mooring *** found that turbulent mixing bursts persisted in the thermocline of all three ***,the interior turbulent mixing layers(ITMLs)could occur in probability of approximately 68%,53%,and 48%at the three sites,*** overall occurrence probability shows obvious and similar biannual variations at 140°W and 170°W,which is higher in boreal from late summer to winter and lower in ***,the ITMLs are primarily located above the EUC core and prevail in deeper(shallower)layers from late summer to winter(spring).Most ITMLs(70%)lasted for hours to 3 days,and a few of them(15%)for more than 7 *** thicknesses of ITMLs were concentrated between 15 and 55 *** 165°E,the vertical distribution of ITML occurrence probability was different from that at 140°W and 170°W,as it did not show a preference for depths;the durations of ITMLs are short(also from hours to several days)and their thicknesses were between 5 and 25 *** properties,particularly the high occurrence probability,and short durations demonstrated the persistence of thermocline mixing in the western to eastern equatorial Pacific thermocline and confirmed the generation mechanism by persistent equatorial waves as well.