基于Argo资料的吕宋岛以东海域水团特征分析

基于中国Argo实时资料中心发布的2004年1月至2017年12月Argo全球温盐资料,运用直线定位法和隶属关系,对吕宋岛以东海域(120°~140°E,10°~30°N)水团进行分析,划分出北太平洋次表层水团(NPSSW)和北太平洋中层水团(NPIW)的分布范围。次表层水团位于50~220 m深度,分布在10°~28°N范围内,温度16.61~27.60℃,盐度34.68~35.14,核心范围春夏季较大,秋冬季较小。中层水团位于280~900 m深度,分布在10~30°N范围内,温度3.67~16.55℃,盐度34.11~34.67,核心范围季节变化较弱,整体位于18°N以北。次表层与中层水团核心温盐具有一定的年际变化特征,次表层水团与气候变化相关性较好,核心温度和盐度均存在4 a的变化周期;而中层水团与气候变化相关性较差,核心温度和盐度则分别具有3.5 a和3 a的变化周期。

Characteristics of the Water Mass to the East of the Luzon Island Based on Argo Data

Based on the Argo profiles from January 2004 to December 2017 released by the Argo Real-time Data Center of China,the water masses in the region of 120°-140°E and 10°-30°N,to the east of the Luzon Island in the northwestern Pacific Ocean,were analyzed using the linear positioning method and membership relationship,and the distribution of North Pacific subsurface water mass and North Pacific intermediate water mass were determined.The subsurface water mass locates at depth of 50-220 m between 10°-28°N with temperature of 16.61-27.60℃and salinity of 34.68-35.14 and its core area is larger in spring and summer but smaller in autumn and winter.The intermediate water mass locates at depth of 280-900 m between 10°-30°N,with the temperature of 3.67-16.55℃and salinity of 34.11-34.67,and its core area has little seasonal variation and in the north of 18°N.The core temperature and salinity of both water masses show interannual variations.In the subsurface layer,both the core temperature and salinity have four-year variation period and good correlation with climate change indices.In the intermediate layer,the interannual variation period of the core temperature is 3.5 years,but for the core salinity the period is 3 years,both have poor correlations with the climate change indices.