Scientists warn that the Atlantic Meridional Overturning Circulation (AMOC), including the Gulf Stream, is weakening and could potentially collapse within the next 50 to 100 years, a much sooner timeline than previously thought.

The risk of a collapse is now considered imminent, with estimates suggesting a 70% chance of stopping under current emission scenarios and even a 25% chance at low emission levels.

Such a collapse would drastically alter global weather patterns, increasing extreme weather events and shifting precipitation, especially in the tropics and Southern Hemisphere.

Even if the AMOC weakens significantly, models suggest some residual heat transport would continue at only 10-20% of current levels, but this would still have major climate implications.

The AMOC is currently at its lowest level in 1600 years due to increased greenhouse gases, with recent data showing the weakest circulation in the past 1000 years since 2004.

Observations over the last 5-10 years confirm a trend of weakening circulation, raising concerns about a potential full stop by the end of the century.

While some studies dispute the likelihood of a complete collapse within this century, there is a consensus that a substantial weakening is imminent and could have severe environmental and societal impacts.

The probability of collapse has increased from less than 10% to as high as 25%, emphasizing the urgent need for immediate emission reductions to prevent catastrophic outcomes.

A collapse could cause regional climate changes such as rapid cooling in parts of Europe and North America, shorter growing seasons, and even expansion of Arctic ice to regions like the English Channel.

Severe climate impacts from a collapse include displacement of the tropical rainfall belt, extreme winter cooling, summer droughts in Western Europe, and sea level rise of approximately 50 centimeters.

Recent studies indicate the weakening of the AMOC since 2004, with the current state being the weakest in the past millennium, highlighting the accelerating pace of change.

Modeling extending the timeline to 2300-2500 years suggests a 'point of no return,' after which the collapse could be inevitable, occurring 50-100 years later.

Climate change accelerates the weakening of the AMOC through increased freshwater input from melting ice, reduced salinity, and decreased temperature gradients, which hinder the sinking of dense water in the North Atlantic.