Gulf Stream Nearing ‘Day After Tomorrow' Tipping Point
Scientists say the increased melting of arctic freshwater is causing an imbalance in the salinity of seawater, and this could lead to plummeting temperatures in the north.
POTSDAM, GERMANY — A team of scientists who study the world’s ocean currents say the increased melting of arctic freshwater is causing an imbalance in the salinity of seawater in the north Atlantic.
They say this could lead to a very sudden shutdown of the current that carries warm water to the planet’s northern reaches, causing a sudden and dramatic drop in temperatures in North America and Europe, as well as disastrous food shortages worldwide. Here are the details:
The Guardian reports that climate scientists have detected warning signs of the collapse of the Gulf Stream, one of the planet’s main potential tipping points. The research found “an almost complete loss of stability over the last century” of the currents that researchers call the Atlantic meridional overturning circulation, or AMOC.
The currents are already at their slowest point in at least 1,600 years, but the new analysis shows they may be nearing a shutdown.
Such an event would have catastrophic consequences around the world, severely disrupting the rains that billions of people depend on for food in India, South America and West Africa, while increasing storms and lowering temperatures in Europe.
The AMOC is driven by dense, salty seawater sinking into the Arctic Ocean, but the melting of freshwater from Greenland’s ice sheet is slowing the process down earlier than climate models suggested.
The analysis was based on 'fingerprints' the AMOC leaves in surface temperature and salinity patterns. It showed a 'critical threshold' is being reached beyond which the system may collapse.
While some scientists are sounding the alarm, others sound less certain. David Thornalley of University College London, whose work showed the AMOC is at its weakest point in 1,600 years, said: “These signs of decreasing stability are concerning. But we still don’t know if a collapse will occur, or how close we might be to it.”
NEXT ON TOMONEWS
‘Dead Zone’ Growing, Killing Oregon’s Sea Crabs