The Atlantic Meridional Overturning Circulation is weakening and may be approaching a critical tipping point, according to recent scientific observations [1, 2].
This slowing of the AMOC matters because the current regulates global heat distribution. A collapse could trigger drastic temperature shifts across Europe and alter sea levels along the U.S. East Coast, affecting cities like New York City and regions such as Florida [4, 5].
Researchers publishing in Science Advances in April 2026 reported that the current is slowing at various locations across the Atlantic [3]. The study utilized buoy measurements taken at four latitudes in the western Atlantic to track these changes [4].
Climate scientists, including Professor Stefan Rahmstorf, said the AMOC is now weaker than it has been in at least a millennium [1]. Observations reported up to spring 2026 indicate that the circulation is failing to move warm surface water northward as efficiently as in previous eras [2].
The weakening is driven by rising global temperatures and an increase in freshwater input from melting glaciers [1, 3]. This influx of freshwater reduces the salinity and density of the surface water, preventing it from sinking and driving the conveyor-belt motion of the current.
Scientists said the system is moving closer to a collapse than previously estimated [5]. The loss of this circulation would disrupt the transport of heat from the tropics toward the North Atlantic, a process essential for maintaining the temperate climate of Western Europe.
“The AMOC is now weaker than it has been in at least a millennium”
The potential collapse of the AMOC represents a systemic risk to global climate stability. Unlike gradual warming, a tipping point implies a rapid, non-linear shift that could permanently alter agricultural viability in Europe and accelerate coastal flooding in the US. The alignment of buoy data with long-term climate models suggests that the window for preventative action is narrowing as freshwater runoff from polar ice continues to disrupt ocean salinity.
