The CO2 uptake by the Southern Ocean (<35°S) varies substantially on all timescales and is a major determinant of the variations of the global ocean carbon sink. Particularly strong are the decadal changes characterized by a weakening period of the Southern Ocean carbon sink in the 1990s and a rebound after 2000. The weakening in the 1990s resulted primarily from a southward shift of the westerlies that enhanced the upwelling and outgassing of respired (i.e., natural) CO2. The concurrent reduction in the storage rate of anthropogenic CO2 in the mode and intermediate waters south of 35°S suggests that this shift also decreased the uptake of anthropogenic CO2. The rebound and the subsequent strong, decade-long reinvigoration of the carbon sink appear to have been driven by cooling in the Pacific Ocean, enhanced stratification in the Atlantic and Indian Ocean sectors, and a reduced overturning. Current-generation ocean models generally do not reproduce these variations and are poorly skilled at making decadal predictions in this region.

中文翻译：

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可变的南方海洋碳汇。

南部海洋（<35°S）吸收的二氧化碳在所有时间尺度上都有很大变化，并且是全球海洋碳汇变化的主要决定因素。年代际变化尤为强烈，其特征是1990年代南大洋碳汇减弱的时期和2000年之后的反弹。1990年代的减弱主要是由于西风的南移，这增强了呼吸道的上升和放气（即，自然）CO2。在35°S以南的中部和中间水域，人为二氧化碳的储存速率同时降低，这表明这种转变也降低了人为二氧化碳的吸收。碳汇的反弹以及随后长达十年之久的强劲复苏，似乎是由太平洋的降温驱动的，加强了大西洋和印度洋地区的分层，并减少了倾覆。当前一代的海洋模型通常不会重现这些变化，并且在该地区进行年代际预测方面的技能很差。