Interhemispheric Contrasts of Ocean Heat Content Change Reveals Distinct Fingerprints of Anthropogenic Climate Forcings
Interhemispheric Contrasts of Ocean Heat Content Change Reveals Distinct Fingerprints of Anthropogenic Climate Forcings
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DOI：
10.1029/2023gl102741
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发表时间：
2023-08
影响因子：
5.2
通讯作者：
Jia‐Rui Shi;S. Wijffels;Young‐Oh Kwon;S. Xie
中科院分区：
文献类型：
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作者：
Jia‐Rui Shi;S. Wijffels;Young‐Oh Kwon;S. Xie
近几十年来，温室气体(GHGs)和人为气溶胶(AAs)都推动了地球能源失衡的重大变化。然而，当使用全球或半球平均时，它们各自在海洋热含量(OHC)变化中的指纹一直很难分离和检测。基于模式识别分析，我们发现，由于大气和海洋环流系统的南移，在历史的OHC变化中，AAS驱动了20°-35°纬度带内的半球间不对称。这种强迫模式不同于温室气体诱导的模式，后者主导着高纬度地区的不对称性。此外，研究还发现，这种重要的气溶胶强迫OHC趋势模式只能在分析的20年或更长时间的周期内捕捉到，包括1975-1990年。利用这些不同的时空特征，我们表明，海洋观测中气溶胶气候强迫的指纹可以与更强的温室气体诱导信号和内部变率区分开来。
During recent decades, both greenhouse gases (GHGs) and anthropogenic aerosols (AAs) drove major changes in the Earth's energy imbalance. However, their respective fingerprints in changes to ocean heat content (OHC) have been difficult to isolate and detect when global or hemispheric averages are used. Based on a pattern recognition analysis, we show that AAs drive an interhemispheric asymmetry within the 20°‐35° latitude band in historical OHC change due to the southward shift of the atmospheric and ocean circulation system. This forced pattern is distinct from the GHG‐induced pattern, which dominates the asymmetry in higher latitudes. Moreover, it is found that this significant aerosol‐forced OHC trend pattern can only be captured in analyzed periods of 20 years or longer and including 1975–1990. Using these distinct spatiotemporal characteristics, we show that the fingerprint of aerosol climate forcing in ocean observations can be distinguished from both the stronger GHG‐induced signals and internal variability.