Suppressed p CO 2 in the Southern Ocean due to the interaction between current and wind
Suppressed p CO 2 in the Southern Ocean due to the interaction between current and wind
复制标题
DOI：
10.1029/2021jc017884
复制
发表时间：
2021-11
期刊：
影响因子：
--
通讯作者：
K. Kwak;Hajoon Song;J. Marshall;H. Seo;D. McGillicuddy
中科院分区：
文献类型：
--
作者：
K. Kwak;Hajoon Song;J. Marshall;H. Seo;D. McGillicuddy
南大洋是吸收人为活动产生的二氧化碳的重要区域，由于大量的中尺度弯曲和涡旋，南大洋具有强烈的表面流。这些特征与风相互作用并改变从大气到海洋的动量传递。虽然已知这种相互作用会减少动量转移，但它们对海气碳交换的影响仍不清楚。利用1/20 °物理-地球化学耦合模式，研究了海流-风相互作用对南大洋表层碳浓度和海气碳交换的影响。流-风相互作用降低了冬季海洋表面CO2分压（pCO2），主要是北方亚南极锋以南。它还减少了夏季的pCO2，表明吸收增强，但没有达到冬季损失的程度。因此，净释气的CO2被认为是减少了约17%时，包括流-风相互作用。这些变化是垂直混合和Ekman辐散共同作用的结果。溶解无机碳（DIC）的预算分析表明，削弱垂直混合的气流-风的相互作用减少了从下面的碳供应，特别是在冬季。较弱的风应力还降低了夏季次表层DIC浓度，从而影响冬季碳的垂直扩散通量。我们的研究表明，忽略南大洋的海流-风相互作用可能会高估冬季的二氧化碳释气。
The Southern Ocean, an important region for the uptake of anthropogenic carbon dioxide (CO 2 ), features strong surface currents due to substantial mesoscale meanders and eddies. These features interact with the wind and modify the momentum transfer from the atmosphere to the ocean. Although such interactions are known to reduce momentum transfer, their impact on air-sea carbon exchange remains unclear. Using a 1/20° physical-biogeochemical coupled ocean model, we examined the impact of the current-wind interaction on the surface carbon concentration and the air-sea carbon exchange in the Southern Ocean. The current-wind interaction decreased winter partial pressure of CO 2 ( p CO 2 ) at the ocean surface mainly south of the northern subantarctic front. It also reduced p CO 2 in summer, indicating enhanced uptake, but not to the same extent as the winter loss. Consequently, the net outgassing of CO 2 was found to be reduced by approximately 17 % when including current-wind interaction. These changes stem from the combined effect of vertical mixing and Ekman divergence. A budget analysis of dissolved inorganic carbon (DIC) revealed that a weakening of vertical mixing by current-wind interaction reduces the carbon supply from below, and particularly so in winter. The weaker wind stress additionally lowers the subsurface DIC concentration in summer, which can affect the vertical diffusive flux of carbon in winter. Our study suggests that ignoring current-wind interactions in the Southern Ocean can overestimate winter CO 2 outgassing.