Improved winter data coverage of the Southern Ocean CO2 sink from extrapolation of summertime observations
Improved winter data coverage of the Southern Ocean CO2 sink from extrapolation of summertime observations
复制标题
根据夏季观测结果推断，改善了南大洋二氧化碳汇的冬季数据覆盖范围
DOI：
10.1038/s43247-022-00592-6
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发表时间：
2022
影响因子：
7.9
通讯作者：
Mackay N
中科院分区：
文献类型：
--
作者：
Mackay N
南大洋是一个重要的人为CO2汇，但它是观测最少的海洋盆地之一，因此在CO2通量重建中存在很大的不确定性。最近的一项尝试是利用南极极锋以南的夏季地下观测数据，对历史上稀疏的冬季采样进行“伪”冬季地表pco2观测。在这里，我们提出了南大洋二氧化碳汇的估计，该估计结合了基于机器学习的制图方法和一组更新的伪观测，与历史数据集相比，该方法将区域冬季数据覆盖率提高了68%。我们的研究结果证实了冬季覆盖度的提高对重建的影响不大，略微增强了2000年代的吸收趋势。在调整了地表边界层温度效应后，我们发现2004-2018年极锋以南的平均碳汇为- 0.16±0.07 PgC /年，35°S以南的平均碳汇为- 1.27±0.23 PgC /年，与大气数据的独立估计一致。
The Southern Ocean is an important sink of anthropogenic CO2, but it is among the least well-observed ocean basins, and consequentially substantial uncertainties in the CO2flux reconstruction exist. A recent attempt to address historically sparse wintertime sampling produced ‘pseudo’ wintertime observations of surface pCO2using subsurface summertime observations south of the Antarctic Polar Front. Here, we present an estimate of the Southern Ocean CO2sink that combines a machine learning-based mapping method with an updated set of pseudo observations that increases regional wintertime data coverage by 68% compared with the historical dataset. Our results confirm the suggestion that improved winter coverage has a modest impact on the reconstruction, slightly strengthening the uptake trend in the 2000s. After also adjusting for surface boundary layer temperature effects, we find a 2004-2018 mean sink of −0.16 ± 0.07 PgC yr−1south of the Polar Front and −1.27 ± 0.23 PgC yr−1south of 35°S, consistent with independent estimates from atmospheric data.