The Earth's core flow is slowing down and may soon collapse: scientists have debunked this theory (photo).

71% of the Earth's surface is covered by water and is influenced by the ocean and its movements. In the Atlantic Ocean, there exists a system of interconnected currents known as the Atlantic Meridional Overturning Circulation (AMOC), which transports water throughout the global ocean. This system is driven by a combination of winds and ocean density, and prior research has indicated that it is slowing down and may soon face complete collapse—such an event would plunge the planet into climatic chaos, reports PHYS.org.

The Earth's key current not only distributes heat, moisture, and nutrients from the ocean but also regulates the climate and weather patterns on Earth. As the climate crisis looms over the planet and the atmosphere heats up, many scientists are concerned that freshwater from melting polar ice sheets could significantly disrupt, if not destroy, the AMOC. Previous studies have also confirmed this theory, revealing that a decline in AMOC would have severe consequences for Earth's climate, while its total collapse would be truly catastrophic.

However, research into the long-term future remains uncertain. In a new study, a team of scientists from the Woods Hole Oceanographic Institution chose not to focus on what awaits us in the future but instead quantitatively assessed the past. According to the team, this approach will help understand the direction in which we are headed.

The results of the new study suggest that the AMOC has been slowing down over the last 60 years. In simple terms, the scientists' findings indicate that the Earth's key current is currently more stable than previously thought.

According to co-author of the study, freelance physical oceanographer and associate professor at the University of Georgia, Nicholas Fucale, their conclusions suggest that the Atlantic overturning has not yet decreased. Nevertheless, the scientists acknowledge that this does not predict the future; it merely indicates that the expected changes have not yet occurred.

At the same time, the team's findings contradict previous work. For instance, in a 2018 study, researchers claimed that the AMOC had decreased over the past 70 years. Notably, that earlier study relied on sea surface temperature measurements to understand how the AMOC had changed. However, in the new research, scientists found that sea surface temperature is not as reliable an indicator as previously believed.

In the new study, the researchers utilized new data from the Coupled Model Intercomparison Project (CMIP), Earth climate models developed by the World Climate Research Program. A total of 24 different models were used, and the scientists discovered that the most recent available data on sea surface temperature inaccurately reconstructs the AMOC.

Next, the researchers examined another measure: air-sea heat fluxes, which represent the exchange of heat from the ocean to the atmosphere. Essentially, the stronger the AMOC, the more heat is released from the ocean into the atmosphere over the North Atlantic.

The authors derived this AMOC proxy using CMIP models and then applied it to observational data. The best data on surface heat fluxes over the North Atlantic were obtained from reanalysis products, which incorporate direct observations into the model, similar to how weather forecasts operate. The scientists focused on two reanalysis datasets covering the period since the late 1950s to reconstruct the AMOC.

The results clearly indicate that the AMOC is more stable than previously thought. In simple terms, this could mean that the Earth's key current is actually further from a tipping point than previously believed. At the same time, the scientists acknowledge that the Earth's key current will indeed slow down in the future—there is no mystery about that; however, whether the flow will collapse remains a subject of debate. Now, the scientists believe that humanity still has time to take action.