Lee Huiji, Noh Kyung-Min, Oh Ji-Hoon, Park So-Won, Shin Yechul, Kug Jong-Seong
School of Earth and Environmental Sciences, Seoul National University, Seoul, South Korea.
Princeton University/Atmospheric and Oceanic Sciences Program, Princeton, NJ, USA.
Nat Commun. 2025 Apr 3;16(1):3199. doi: 10.1038/s41467-025-57724-7.
The ocean is a crucial sink for anthropogenic CO emissions, yet its future response remains uncertain. Here, using the Community Earth System Model (CESM2) under different CO emission rates, we find a pronounced weakening of ocean CO uptake in the Subpolar North Atlantic (SPNA), distinct from the global response. Initially, the SPNA is an effective CO sink, but due to the contraction of deep convection, the uptake decreases and the oceanic pCO exceeds the global average. Recognizing the importance of regional ocean circulation in CO uptake, we identify a nonlinear relationship between environmental conditions and uptake response, revealing consistent thresholds for the emergence of uptake weakening. These findings are also reproduced in the Coupled Model Intercomparison Project Phase 6, confirming their robustness. Overall, the distinct uptake response reflects the key role of regional dynamics in regulating the CO budget and geochemical environment, which is important for regional CO mitigation strategies.
海洋是人为碳排放的一个关键汇，但它未来的响应仍不确定。在此，我们使用不同碳排放率下的社区地球系统模型（CESM2），发现在北极亚极地地区（SPNA）海洋对二氧化碳的吸收明显减弱，这与全球响应不同。最初，SPNA是一个有效的二氧化碳汇，但由于深层对流的收缩，吸收量减少，海洋pCO超过全球平均水平。认识到区域海洋环流在二氧化碳吸收中的重要性，我们确定了环境条件与吸收响应之间的非线性关系，揭示了吸收减弱出现的一致阈值。这些发现也在耦合模型比较计划第6阶段中得到了重现，证实了它们的稳健性。总体而言这种独特的吸收响应反映了区域动力学在调节碳预算和地球化学环境中的关键作用，这对区域碳减排战略很重要。
