Analysis on characteristics of CO2 fluxes across the air-sea interface of the Yangtze Estuary and adjacent sea in late winter 2016
CHENG Tian-yu1,2, GAO Guo-ping1,2, HU Deng-hui1,2, HUANG Ju1, ZHANG Chun-ling1,2
1. College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China;
2. Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai 201306, China
Abstract：Based on the survey at the Yangtze Estuary and adjacent sea in March 2016,regional distributions of the surface water partial pressure of CO2 and relevant parameters were analyzed,air-sea CO2 fluxes were estimated and physical processes of CO2 source/sink distribution were discussed.Results showed that the surface pCO2 in survey area ranged from 321~575 μatm, generally exhibiting high values at the inner shelf,whereas low values off the shore.Until the end of winter,the distribution of surface pCO2 had been dominated by the mixing between the estuarine water (low temperature,low salinity,high pCO2 ) and the shelf water in the East China sea(high temperature,high salinity,low pCO2),while vertical mixing had little effect on it.The Yangtze Estuary and adjacent sea also served as a weak sink of atmospheric CO2,with a -4.43±7.41 mmol/m2/d average air-sea CO2 flux.In the sight of regional carbon sink intensity,its level in the Changjiang Diluted Water was nearly in balance with that in the atmosphere.The Yellow Sea-East China Sea Mixing Water and Taiwan Warm Current Water were moderate/strong sink of the atmospheric CO2,becoming a major contributor to the ocean absorbed CO2 during winter.
CHENG Tian-yu,GAO Guo-ping,HU Deng-hui et al. Analysis on characteristics of CO2 fluxes across the air-sea interface of the Yangtze Estuary and adjacent sea in late winter 2016[J]. Marine Environmental Science, 2018, 37(2): 264-273.
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