The region between a shallow mixed layer and a deep isothermal layer resulting from salinity stratification is called a barrier layer (BL). Since BLs hinder the surface heat and momentum exchange with the ocean subsurface, they play an important role in air‐sea interaction. Synoptic features and formation of BLs and associated temperature inversions (TIs) in the Eastern Pacific Fresh Pool (EPFP) were investigated using shipboard observations. BLs and TIs were found in the high‐precipitation EPFP, a frontal transition zone (FTZ) and in the sea surface salinity (SSS) front during a 2016 boreal summer cruise. During a 2017 boreal autumn cruise, BLs and TIs were found from the southern part of the EPFP to the SSS front. The BLs in the SSS front and the FTZ were meridionally displaced from the precipitation maximum during both the 2016 and 2017 cruises. Freshening and cooling by tilting of both the isohalines and isotherms of the SSS front occurred via Ekman and geostrophic flow during both cruises, and also within the EPFP during 2016. The SSS front was a dominant contributor to the density gradient in the horizontal plane. A high dissolved oxygen content observed within BLs confirmed that the surface flow plays an important role in the BL and TI formation through the tilting process. Patchy distribution of freshening and cooling by tilting implies an intermittent BL and TI formation with short time scales.

中文翻译：

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SPURS-2野战期间东太平洋的上层海洋分层

由盐分分层产生的浅混合层和深等温层之间的区域称为阻挡层（BL）。由于BL阻碍了与海表层的地表热量和动量交换，因此它们在海气相互作用中起着重要的作用。使用船上观测资料，对东太平洋淡水库（EPFP）中BL的天气特征和形成以及相关的温度反转（TIs）进行了调查。在2016年的夏季北方航行期间，在高降水量EPFP，额叶过渡带（FTZ）和海面盐度（SSS）前缘发现了BL和TI。在2017年的秋季秋季航行中，发现了从EPFP南部到SSS前沿的BL和TI。在2016年和2017年的航行中，SSS前缘和自由贸易区的BL均经子午线偏离了最大降水量。在两次航行期间以及2016年期间，通过Ekman和地转流使SSS锋面的等咸线和等温线倾斜，从而使其变凉和冷却。此外，2016年在EPFP内也是如此。SSS锋面是水平面密度梯度的主要贡献者。在BL内观察到的高溶解氧含量证实，表面流在倾斜过程中在BL和TI的形成中起着重要作用。通过倾斜使新鲜和冷却的斑点分布意味着具有短时间尺度的间歇性BL和TI形成。在BL内观察到的高溶解氧含量证实，表面流在倾斜过程中在BL和TI的形成中起着重要作用。通过倾斜使新鲜和冷却的斑点分布意味着具有短时间尺度的间歇性BL和TI形成。在BL内观察到的高溶解氧含量证实，表面流在倾斜过程中在BL和TI的形成中起着重要作用。通过倾斜使新鲜和冷却的斑点分布意味着具有短时间尺度的间歇性BL和TI形成。