In a shocking discovery, a study has found that the circulation of the Atlantic Ocean is heading towards a tipping point that could have severe implications for both the climate system and humanity. The scientists behind the research have expressed their concern about the forecasted rapid collapse once this tipping point is reached. However, it remains uncertain when exactly this tipping point will occur.

Using computer models and historical data, the researchers have developed an early warning indicator for the breakdown of the Atlantic meridional overturning circulation (Amoc) - a crucial system of ocean currents that plays a significant role in global climate regulation. Their findings indicate that Amoc is already on track towards an abrupt shift, which has not been observed in over 10,000 years.

Amoc, which includes a part of the Gulf Stream and other powerful currents, acts as a marine conveyor belt, carrying heat, carbon, and nutrients from the tropics to the Arctic Circle. This process helps distribute energy around the Earth and moderates the impact of human-induced global heating. However, the system is being weakened by the accelerated melting of Greenland's glaciers and Arctic ice sheets. The influx of freshwater obstructs the sinking of saltier, warmer water from the south, further eroding Amoc's stability.

Previous research has revealed that Amoc has declined by 15% since 1950 and is currently in its weakest state in more than a millennium. Speculations about an approaching collapse have sparked debates, with varying opinions on its severity. Last year, one study suggested that a tipping point could happen between 2025 and 2095, while the UK Met Office deemed large, rapid changes in Amoc as "very unlikely" in the 21st century.

However, the new paper published in Science Advances has broken new ground by examining warning signs in the salinity levels of the southern extent of the Atlantic Ocean, between Cape Town and Buenos Aires. By simulating changes over a 2,000-year period using computer models of global climate, the researchers have discovered that a gradual decline in Amoc can lead to a sudden collapse in less than 100 years, with catastrophic consequences.

The study's findings provide a clear answer regarding the possibility of an abrupt shift in Amoc. The researchers warn that this news is devastating for both the climate system and humanity. Previously, the tipping point of Amoc was considered to be a theoretical concept that would disappear once the full climate system and its feedbacks were taken into account.

The consequences of an Amoc collapse are mapped out in the study as well. Regions in the Atlantic would experience a rise in sea levels of up to a meter, leading to the flooding of many coastal cities. The Amazon rainforest would face a reversal of its wet and dry seasons, potentially pushing it beyond its own tipping point. Global temperatures would become more erratic, and the southern hemisphere would heat up while Europe experiences a dramatic cooling and decreased rainfall. However, these changes would occur 10 times faster than the current trend, making adaptation nearly impossible.

The lead author of the paper, René van Westen from Utrecht University, expressed surprise at the speed at which this tipping point could occur and emphasized its devastating impact. While it is still uncertain when this collapse will take place, the changes it brings will be irreversible on human timescales.

"We are moving towards it. That is kind of scary," said van Westen. "We need to take climate change much more seriously."

This study serves as a stark reminder of the urgency for action to mitigate climate change and its potential consequences on our planet and future generations. The findings emphasize the need to prioritize efforts to reduce greenhouse gas emissions and address the alarming degradation of the Earth's climate system.