germtheory — 4 years ago(August 06, 2021 01:48 PM)

Climate crisis: Scientists spot warning signs of Gulf Stream collapse
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 (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; increasing storms and lowering temperatures in Europe; and pushing up the sea level off eastern North America. It would also further endanger the Amazon rainforest and Antarctic ice sheets.
The complexity of the AMOC system and uncertainty over levels of future global heating make it impossible to forecast the date of any collapse for now. It could be within a decade or two, or several centuries away. But the colossal impact it would have means it must never be allowed to happen, the scientists said.
They say it can happen faster than expected.
Boer’s research, published in the journal Nature Climate Change, is titled “Observation-based early-warning signals for a collapse of the AMOC”. Ice-core and other data from the last 100,000 years show the AMOC has two states: a fast, strong one, as seen over recent millennia, and a slow, weak one. The data shows rising temperatures can make the AMOC switch abruptly between states over one to five decades.
When the movie was released they were not worried about a one to five decade time scale.
The type of global climate change that happens in the movie – where global warming diverts warm ocean currents and plunges the world abruptly into a new ice age – could possibly happen in real life, "but it would take many, many decades or even a century or more," said Susan Lozier, the Truman and Nellie Semans/Alex Brown & Sons Associate Professor of Earth and Oceans Sciences at Duke's Nicholas School of the Environment and Earth Sciences.