2015年冬季南黄海水文特征及海-气CO2通量分析

Hydrological features and air-sea CO2 fluxes of the Southern Yellow Sea in the winter of 2015

摘要:

基于2015年冬季在南黄海海域现场观测获得的CTD和CO₂等数据，分析了该海域海-气CO₂通量，探讨了该海域冬季温、盐度和表层CO₂分压（pCO₂）等要素的分布特征及其影响因素。结果表明：冬季南黄海西侧海域受黄海沿岸流的影响，呈现低温、低盐的特征，南黄海中部受黄海暖流影响，呈高温高盐特征；南黄海靠近沿岸海域水体垂直混合强烈，温盐垂直分布较为均匀。南黄海海域表层pCO₂平均值为（385.34±43.62）μatm。表层pCO₂分布具有明显的区域差异，海区中部pCO₂整体上大于近岸，因受长江冲淡水与黄海沿岸流的水平及垂直混合作用，长江口北部局部区域最高通量达27.81 mmol/（m²·d），但总体表现为大气碳汇，平均通量达（-2.47±3.91）mmol/（m²·d）；山东半岛东南部海域较高的pCO₂受控于温度，同时与黄海沿岸流带来的高碳酸盐等水体的混合有关，表现为大气碳源，平均通量为（0.11±0.80）mmol/（m²·d）。整个调查海域平均通量为（-2.24±3.74）mmol/（m²·d），表现为大气CO₂的碳汇。

Abstract:

This paper summarized the characteristics of the temperature, salinity,surface CO₂ partial pressure (pCO₂) and sea-air CO₂ flux based on the in-situ CTD, CO₂ and others data in the South Yellow Sea during the winter of 2015. The results indicated that the west coast of the Yellow Sea was low temperature and low salt, affected by Yellow Sea Coastal Current. The central part of the southern Yellow Sea was high temperature and high salt, affected by the Yellow Sea Warm Current. In the coast, it was well mixed with generalized temperature and salinity in vertical. The average value of surface pCO₂ was (385.34±43.62)μatm. The distribution of surface pCO₂ had obvious regional differences. In the central sea, the pCO₂ was larger than that of the nearshore. Due to horizontal and vertical mixture of the Yangtze River water and the Yellow Sea Coastal Current, the northern part of the Changjiang River Estuary was atmospheric carbon sink where the maximum flux was 27.81 mmol/ (m²·d). However,overall regional average flux was (-2.47±3.91)mmol/ (m²·d) The higher pCO₂ in the southeastern of Shandong Peninsula controlled by the cold water, correlated to mixture of the high carbonate water brought by the Yellow Sea Coastal Current and the average flux was (0.11±0.80)mmol/ (m²·d). The winter mean flux in the Southern Yellow Sea was (-2.24±3.74)mmol/ (m²·d),which was carbon sink of the atmospheric CO₂.