Temperature, salinity, density and dissolved oxygen profiles from the World Ocean Database and Argo floats in the eastern South Pacific over the 1928-2018 period

in situ ocean vertical profiles of temperature, salinity, density and dissolved oxygen concentration in the eastern south pacific were obtained over the period 1928-2018 from the world ocean database 2013 (18th september 1928 to 29th june 2015), the international argo program (23th november 2007 to 21st february 2018), and argo profiles available from the chilean community (31th october 2005 to 26th may 2011). only quality controlled data were selected. the wod2013 database is a compilation of profiles from ocean stations (osd), some profiling floats not present in the argo database (pfl), and ctd-o data (conductivity-temperature-depth-oxygen) obtained from several oceanographic cruises focused on the characterization of water-masses distribution from the mesoscale to regional-basin scales. using wod2013 and argo data, the vertical variability of the oxygen minimum zone (omz) in the eastern south pacific (esp; 0-40°s) was characterized in terms of the influence exerted by anticyclonic intra-thermocline eddies (ites), subsurface intensified mesoscale features frequently generated in the coastal upwelling zone off peru and chile. the unique lens-shape signature that ites leave on temperature, salinity and dissolved oxygen vertical distributions was used as a proxy to assess their influence on the vertical omz boundaries and thickness. correlation analyses were performed between anomalous depth (and vertical displacements) of oxyclines and isopycnals/isotherms, together with an objective eddy detection method based on satellite altimetry to identify the location of such profiles (i.e. outside or inside eddies of cyclonic and anticyclonic nature). results indicate that most of the vertical fluctuations in the climatological omz take a lens-shape signature, and that those at mesoscale are largely due to ites. ites are a main driver of the upper oxycline variability in the coastal band and the coastal transition zone (3-10° from the coast) and also beyond it at mid-latitudes (12-26°s). the influence of ites on the upper and lower oxycline variability is mostly found within the horizontal (offshore) climatological boundary of the omz, suggesting that ites play a role in the omz offshore extension.

自1928年至2018年，通过对世界海洋数据库2013年版（自1928年9月18日至2015年6月29日）、国际Argo计划（自2007年11月23日至2018年2月21日）以及智利社区提供的Argo资料（自2005年10月31日至2011年5月26日）进行综合，获取了东南太平洋地区的现场海洋垂直温度、盐度、密度及溶解氧浓度剖面数据。仅选取了经过质量控制的资料。WOD2013数据库汇集了来自海洋观测站（OSD）、部分未在Argo数据库中出现的浮标剖面（PFL）以及来自数个专注于从中尺度至区域海域尺度水团分布特征表征的海洋学航次中获得的CTD-O（电导率-温度-深度-氧）数据。利用WOD2013和Argo数据，对东南太平洋（ESP；0-40°S）的氧亏损区（OMZ）的垂直变化进行了描述，并分析了反气旋性中层环流涡漩（ITES）的影响，这些涡漩是秘鲁和智利沿岸上升流区中常见的中层加强特征。以ITES在温度、盐度及溶解氧垂直分布上留下的独特透镜状特征作为其影响OMZ垂直边界和厚度的代理。通过对异常深度（及垂直位移）的氧跃层和等密度线/等温线的相关性分析，以及基于卫星测高的客观涡漩检测方法，确定了此类剖面的位置（即位于气旋性或反气旋性涡漩之外或之内）。结果表明，大多数气候学OMZ的垂直波动呈现透镜状特征，其中中尺度波动主要归因于ITES。ITES是沿海带和沿海过渡带（距海岸3-10°）以及中纬度（12-26°S）上氧跃层变率的主要驱动因素。ITES对上下氧跃层变率的影响主要在OMZ的横向（离岸）气候边界内，这表明ITES在OMZ离岸扩展中发挥着作用。