Gulf Stream Could Disappear Within Two Years
Starting from 2025 and extending throughout the 21st century, the Atlantic Gulf Stream, a crucial regulator of the Northern Hemisphere's climate, could completely vanish. This alarming scenario emerges much earlier than previously anticipated, though not all scientists are in agreement.
Live Science reports on this concerning development.
The Gulf Stream is a component of the Atlantic Meridional Overturning Circulation (AMOC), transporting warm waters from the tropics northward and vice versa. The potential disappearance of this current could trigger rapid temperature drops, ecosystem disruptions, and storms across the planet. The disruption of this circulation might cause temperatures in Europe and North America to plummet by 5 degrees Celsius over a decade.
The window for a potential collapse of the Atlantic Meridional Overturning Circulation could open as soon as 2025 and extend throughout the century.
"The tipping point, if we continue greenhouse gas emissions at the current rate, is much earlier than we expected," stated co-author of the study, Susanne Ditlevsen.
However, oceanographers and climate experts have noted that the study comes with a degree of uncertainty, suggesting that the situation might not be as dire as predicted by the researchers. In the near future, scientists plan to update their model and narrow down the forecast window.
The currents within the Atlantic Ocean function as an expansive global conveyor, transporting oxygen, nutrients, carbon, and heat across the Earth. Warm southern waters, saltier and denser, flow northward, cool down, and sink in higher latitudes, releasing heat into the atmosphere. This process then leads the cooled water to drift southward, warm up once again, and repeat the cycle. However, climate change has been slowing down this flow. The influx of fresh water from melting ice has reduced the water's density and salinity, while recent studies revealed that the current is at its weakest in over a thousand years.
The region near Greenland, where the southward-flowing waters submerge (known as the North Atlantic subpolar gyre), borders an area experiencing record-low temperatures, while surrounding seas are experiencing elevated levels, forming a cold-water "blob" that is continually expanding.
The last time the AMOC switched modes was during the last ice age, resulting in a temperature increase of 18 to 27 degrees Fahrenheit (10 to 15 degrees Celsius) near Greenland over a decade. If it were to shut down, the temperature in Europe and North America could drop by 9 degrees Fahrenheit (5 degrees Celsius) over the same timeframe.
Direct measurements of AMOC strength have only been available since 2004. To analyze the flow's changes over an extended period, researchers examined surface temperature records from the subpolar circulation between 1870 and 2020, a system they believe contributes to the "robustness" of the AMOC circulation. Integrating this data into a statistical model, researchers evaluated the weakening of the oceanic current's strength and stability through its increasing year-to-year fluctuations.
The model's outcomes left researchers concerned, confirming their conclusions that the window for a potential collapse of the system could open as soon as 2025.