白令海BR断面海-气CO2通量及其参数特征

通过对2008年夏季白令海大气和海水pCO2连续观测资料,结合BR断面上站位水体垂直采样测量,对白令海不同海区pCO2的分布特征及其与理化参数的关系进行了初步研究,结果表明,将白令海划分为4个具有不同CO2吸收能力的海区,其中陆坡流区碳通量高达-18.72 mmol/(m2·d),是海盆北区的近2倍,比海盆南区高一个量...

Air-sea CO2 flux and its related parameters over BR Section of the Bering Sea

Underway measurements of surface seawater and atmospheric partial pressure of CO₂(pCO₂)along BR Section in the Bering Sea were conducted during the 3^rd Chinese national arctic research expedition (CHINARE-2008) in July 2008. CO₂ system parameters were detected from discrete water column sampling stations as well. The latitudinal distributions of pCO₂in the Bering Sea and its relationships with physical and chemical parameters were discussed. According to the CO₂ uptake capacity, the Bering Sea was divided into 4 regions, Bering shelf region (BS), Bering slope current region (BSC), northern Bering Basin Region (NBB) and southern Bering basin region (SBB). The air-sea CO₂ fluxes of the BSC is up to -18.72 mmol/(m²·d), which is two times as much as that of northern basin and one order of magnitude higher than that of southern basin. pCO₂ in the northern basin and slope increases with temperature, showing a positive correlation. However, the relationship between pCO₂ in the slope and southern basin and temperature was indistinct, suggesting that temperature was not the dominant controlling factor there.pCO₂ in the northern basin and shelf exhibited a positive correlation with salinity, indicating that pCO₂ was mainly affected by mixing of water masses, whereas indistinct relationship existed in the southern basin and slope. The main reason of higher pCO₂ in the southern basin is well-mixed water masses with higher temperature; more saline, higher total dissolved inorganic carbon (DIC) and total alkalinity(TA).On the contrary, the water masses in the slope were significantly different from those of other regions in the Bering Sea, with obvious lower temperature, fresher, lower DIC and TA, leading to lower pCO₂ in the surface seawater.