西南黄海2018年夏季溶解氧分布特征及其影响因素的初步分析

Distribution and potential drivers of dissolved oxygen in the southwestern Yellow Sea in summer 2018

利用2018年夏季在西南黄海的现场调查资料,分析了海温、盐度和溶解氧(dissoloved oxygen,DO)分布特征。海区西侧的江苏沿海有明显的冷水带,冷水带对应表层较高的DO浓度。在海区南侧的长江口附近,盐度由南向北升高,上部海水DO浓度高,下部海水DO浓度低。综合现场观测数据、CCMP(Cross Calibrated Multi-Platform)海面风场遥感数据、AVHRR(NOAA-Advanced Very High Resolution Radiometer)海表温度遥感数据、SMAP(Soil Moisture Active and Passive)海表盐度遥感数据,初步分析了DO的影响因素:夏季偏南风产生从黄海向江苏沿海的上升流,可能有利于形成冷水带和DO高值区;长江冲淡水主要在海水上部向西南黄海扩展,它对水动力的影响及携带的营养盐是形成上层DO高值和底层缺氧现象的重要原因。

The distribution of temperature,salinity and dissolved oxygen(DO)in the southwestern Yellow Sea is analyzed based on in situ observations in Augustand September 2018.The in situ data demonstrate an obvious coldwater zone along the Jiangsu Coast in the west of the study area,where the surface DO had slightly higher concentration.In the south of the study area close to the Yangtze River Estuary,the salinity increased from south to north,and the concentration of dissolved oxygen in the upper layer is markedly higher than that in the lower layer.Based on the observation data,CCMP data,and remote sensing data of sea surface temperature and salinity(AVHRR and SMAP),the possible drivers of dissolved oxygen are analyzed preliminarily.Upwelling from the Yellow Sea to the Jiangsu Coast is initiated by the southerly wind in summer,may account for the cold water and the high concentration of DO in this area.The Changjiang Diluted Water(CDW)mainly extends to the southwest Yellow Sea,where the eutrophic conditions may be responsible for the high DO in the upper layer and hypoxia in the bottom layer.