2021—2023年夏季珠江口及毗邻海域水文特征的时空变化  

Summer hydrological variations during 2021−2023 in the Pearl River Estuary and its adjacent areas

作　　者：郭绍敬 张小波 常景龙 张守文 季轩梁 苗润乔 李建东 朱学明 GUO Shaojing;ZHANG Xiaobo;CHANG Jinglong;ZHANG Shouwen;JI Xuanliang;MIAO Runqiao;LI Jiandong;ZHU Xueming(School of Marine Sciences,Sun Yat-sen University,Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai),Zhuhai 519082,China;National Marine Environmental Forecasting Center,Ministry of Natural Resources,Beijing 100081,China)

机构地区：[1]中山大学海洋科学学院,南方海洋科学与工程广东省实验室(珠海),广东珠海519082 [2]国家海洋环境预报中心,北京100081

出　　处：《热带海洋学报》2025年第1期108-121,共14页Journal of Tropical Oceanography

基　　金：南方海洋科学与工程广东省实验室(珠海)自主科研项目(SML2023SP219);国家自然科学基金项目(42176029)。

摘　　要：利用2021—2023年夏季珠江口及毗邻海域现场调查资料,分析了夏季水文要素的时空变化及其影响因素。研究表明:夏季温盐均表现为东北—西南走向的空间分布特征,但三年调查期间的量值变化显著。平均海表温度2021年最低, 2022年最高;底层海温2021年最高, 2022和2023年依次减小。2022年强径流导致冲淡水向外扩展范围广,海表盐度明显低于2021和2023年;底层盐度2023年最高, 2021和2022年依次减小。中、底层温盐变化与台风过境及陆架低温高盐水入侵有关。2021年台风Lupit过境后垂向温盐混合均匀可直达海底,层结减弱。观测期间陆架水上溯至伶仃洋,在此形成低温区和显著盐度锋面。2022和2023年陆架水入侵依次增强,中、底层海温(盐度)依次降低(增大)。2023年强上升流抑制珠江口冲淡水向陆架扩散,导致陆架海表盐度高于前两年。底层温盐随潮汐而变化,涨潮时高盐冷水向岸运动导致温度下降、盐度升高,退潮时则反之。海表温度与气温具有较好正相关关系,随气温变化明显。Using in-situ data collected by summer cruises during 2021-2023,summer hydrological variations and their influencing factors were studied.The results show that the summer temperature and salinity were charactered by northeast-southwest distribution pattern,while variations in values were significant during the investigation.Mean sea surface temperature(SST)was lowest in 2021 but highest in 2022.Bottom temperature was highest in 2021,but moderate in 2022 and lowest in 2023.Strong runoff caused a significant outward expansion of diluted waters,sea surface salinity(SSS)was strikingly lower in 2022 than those in 2021 and 2023.Bottom salinity was highest in 2023,moderate in 2021 and lower in 2022.Temperature and salinity variations in the middle and low layers were related to the passage of typhoons and invasion of shelf cold and saline water.Those vertical temperature and salinity observed after Typhoon Lupit passed in 2021 mixed homogeneously,weakening stratification.Bottom shelf water intruded into the Lingding Bay,forming a low-temperature zone and apparent salinity front.Middle and bottom temperature(salinity)decreased(increased)owing to the enhanced bottom shelf water intrusion in sequence in 2022 and 2023.In 2023,strong upwelling inhibited the expansion of diluted water seaward to increase SSS over the shelf higher than those in 2021 and 2022.Bottom temperature and salinity varied with the tide,in which the shoreward movement of cold and saline water tended to decrease temperature and increase salinity during flood tide,while the opposite occurred during ebb tide.The positive correlation between SST and air temperature suggested that SST varied with air temperature.

关 键 词：珠江口 水文要素 时空变化 陆架水 向岸风 

分 类 号：P731[天文地球—海洋科学]