基于2007—2018年Argo数据分析全球混合层和障碍层时空特征  

Temporal and Spatial Characteristics of Global Mixed Layer Depth and Barrier Layer Thickness Based on Argo Data from 2007 to 2018

作　　者：于瑶 吴松华[1,2] Yu Yao;Wu Songhua(Department of Marine Technology, College of Information Science and Engineering, Ocean University of China, Qing-dao 266100,China;Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266237, China)

机构地区：[1]中国海洋大学信息科学与工程学院海洋技术系,山东青岛266100 [2]青岛海洋科学与技术试点国家实验室,山东青岛266237

出　　处：《中国海洋大学学报（自然科学版）》2021年第12期123-132,共10页Periodical of Ocean University of China

基　　金：国家重点研究发展计划项目(2016YFC1400904);山东省支持青岛海洋科学与技术试点国家实验室重大科技专项项目(2018ASKJ01-07-03)资助。

摘　　要：为了进一步认识上层海洋中混合层和障碍层的时空变化特征。本文基于Argo(Array for real-time geostrophic oceanography)海洋观测网2007—2018年的温盐数据,使用差值法计算了全球海洋混合层深度(Mixed layer depth,MLD)和障碍层厚度(Barrier layer thickness,BLT),讨论了二者的月均值、季节均值和年均值的空间分布特征和形成机制。研究表明,全球海洋的混合层普遍在夏季浅、在冬季深,随季节变化的特征显著。北半球混合层变化幅度较大,大西洋混合层比同纬度的太平洋深;赤道海区混合层较浅;南半球混合层呈纬向带状分布,60°S附近大洋海域存在显著的深混合层带,南极大陆与该深混合层带之间的海域混合层常年较浅。全球障碍层呈“哑铃状”分布,两半球的高纬度海区是障碍层高发区,障碍层不仅厚且持续时间长,以半年为周期变化,南大洋60°S附近海域显著的厚障碍层带随季节变化;南半球中低纬度海区长期存在障碍层,障碍层冬厚夏薄,且厚度大部分不超过40 m。It is essential to fully understand the temporal and spatial changes of the mixed layer and barrier layer to further analyze the relationship between the ocean movement and to understand of the physical and chemical elements of the ocean.This paper uses the Argo(Array for real-time geostrophic oceanography)oceanographic network data from 2007 to 2018 to calculate the global mixed layer depth(MLD)and the barrier layer thickness(BLT)by threshold method.The temporal and spatial characteri-stics and formation mechanism of monthly,seasonal and annual average data of MLD and BLT are discussed in this paper.It is prominent that the MLD of global ocean varies with the seasons,and is genera-lly shallow in summer and deep in winter.In the northern hemisphere,the MLD varies greatly,and the MLD of the North Atlantic is deeper than that of the North Pacific at the same latitude.The MLD is shallow in the equatorial regions.The MLD of the southern hemisphere shows a zonal band distribution.There is a significant deep mixed zone in the ocean band near 60°S.The MLD in the sea between the Antarctica and the deep mixed zone is shallow.It is found that the profile of the global BLT distribution is just like a dumbbell.The high latitude ocean area of the two hemispheres is a common occurrence area of the barrier layer.The barrier layer is not only thick but also lasts for a long time,and presents a hal-fyear cyclical change.There is a significant thick barrier zone in the sea area near 60°S in the Southern Ocean,and it changes with seasons.In the middle latitude and low latitude of south hemisphere,barrier layer exists for a long time,which is thick in winter and thin in summer,and the BLT of most areas does not exceed 40 m.

关 键 词：ARGO 混合层深度 障碍层厚度 时空变化 

分 类 号：P731.1[天文地球—海洋科学]