Earlier this year, scientists released research findings that suggested an accelerated weakening of Atlantic overturning circulation was likely associated with an optimal salinity fingerprint. 

The Atlantic meridional overturning circulation (AMOC) is a crucial ocean current system that significantly regulates the Earth's climate. Scientists have been trying to understand how human activities, such as the release of greenhouse gases and aerosols, are affecting the AMOC in the long term. However, due to the complexities of the ocean and limited direct measurements, detecting these changes has been challenging.

The recent study has provided evidence that the AMOC has likely weakened at an accelerated rate since the 1980s, primarily due to human-induced factors. This weakening can be seen through the buildup of salt in the South Atlantic, which serves as a fingerprint of the AMOC changes. Interestingly, this signal could be more evident in the North Atlantic due to the interference of natural climate variability.

The study indicates that as human activities continue to impact the environment, the weakening of the AMOC might worsen in the coming decades; this could lead to significant climate impacts globally, affecting weather patterns, sea levels, and ecosystems.

Overall, understanding the AMOC's response to human-induced changes is crucial for predicting and preparing for future climate shifts; by understanding their potential consequences, we can implement strategies to mitigate the impact of anthropogenic forcing on the Earth's climate system.

Zhengyu Liu, Max Thomas Professor of Climate Dynamics and Atmospheric Sciences Program Director at The Ohio State University's Department of Geography, co-authored the study. Liu is also a principal investigator at the Byrd Center.

Read more about this research, published in the journal Nature Communications.

Liu recently shared with Heatmap his thoughts on using climate models, predictions and uncertainties when it comes to weakening the AMOC over time. Read more about Why It's So Hard to Predict a Climate Tipping Point.