A recent study published in the journal Nature Communications has raised fears of a possible collapse of the Atlantic Meridional Circulation (AMOC), a crucial ocean system responsible for transporting warm water to the North Atlantic. The study indicates that unless drastic emission reductions are made, the AMOC could collapse between 2025 and 2095, with a central estimate in 2057. This alarming scenario could lead to a 5-10 degree drop in European temperatures with catastrophic consequences. The Conversation interviewed physicist Peter Ditlevsen and statistician Susanne Ditlevsen to shed light on the findings and address misconceptions surrounding the collapse.
Misconceptions and clarifications:
Susanne Ditlevsen recognizes that there can be confusion between Gulf Stream and AMOC because they are sometimes referred to interchangeably. However, she emphasizes that terminology is not the main issue. The critical issue is the potential collapse of the warm water current, whether it is called AMOC or Gulf Stream. It is important to clarify this distinction so that predictions are not considered unreasonable.
Probability and risk assessment:
The confidence interval of the study, covering the period from 2025 to 2095, has been misrepresented in some media. Ditlevsen explains that the probability of collapse is not evenly distributed over this interval. While collapse by 2025 is unlikely, the central estimate of 2057 poses the greatest risk if greenhouse gas emissions continue at current levels. There is uncertainty in estimating extreme probabilities, but the main conclusion is that there is a significant and potentially underestimated risk of an earlier collapse than previously thought.
Implications for Europe:
If the AMOC collapses in 2057, there will be serious implications for Europe’s climate. Peter Ditlevsen emphasizes that the collapse is likely to happen quickly and stop within a few decades. Such a sudden disruption of ocean currents will lead to a significant temperature drop in Europe, which could be between 5 and 10 degrees Celsius. Such a dramatic change would have devastating effects on ecosystems, agriculture and human livelihoods.
Experts’ opinions:
Dr. Levke Caesar, a climatologist at Maynooth University, warns that the destruction of the AMOC would disrupt the global climate system and lead to regional climate change far beyond Europe. She explains that the AMOC acts like a conveyor belt, redistributing heat and influencing weather patterns around the world. Its destruction would set off a chain reaction of climate shifts affecting precipitation patterns, sea ice formation and ocean circulation.
Professor Stefan Rahmstorf, head of Earth System Analysis at the Potsdam Institute for Climate Impact Research, emphasizes the urgent need to reduce greenhouse gas emissions to reduce the risk of AMOC collapse. He argues that the consequences of such a collapse would be comparable to a “climate bomb” and would have far-reaching and unpredictable effects on the stability of the global climate.
Conclusions:
A potential collapse of the Atlantic meridional circulation poses a significant threat to European climate stability. While there is uncertainty in estimating the exact timing of this collapse, the central estimate of 2057 emphasizes the urgency of drastic emission reductions. The consequences of an AMOC collapse would extend beyond Europe and impact global weather patterns and ecosystems. It is crucial for policy makers and individuals alike to take urgent action to reduce greenhouse gas emissions and secure the future of our planet.
