Gulf stream could collapse as early as 2025, study suggests | Climate crisis | The Guardian
▻https://www.theguardian.com/environment/2023/jul/25/gulf-stream-could-collapse-as-early-as-2025-study-suggests
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Prof Niklas Boers, from the Potsdam Institute for Climate Impact Research in Germany, revealed the early warning signs of Amoc collapse in 2021. “The results of the new study sound alarming but if the uncertainties in the heavily oversimplified model [of the tipping point] and in the underlying [sea temperature] data are included, then it becomes clear that these uncertainties are too large to make any reliable estimate of the time of tipping.”
Prof David Thornalley, at University College London, UK, agreed the study had large caveats and unknowns and said further research was essential: “But if the statistics are robust and a relevant way to describe how the actual Amoc behaves, then this is a very concerning result.”
Dr Levke Caesar, at the University of Bremen, Germany, said using sea surface temperatures as proxy data for the strength of the Amoc currents was a key source of uncertainty: “We only have direct observational data of the Amoc since 2004.”
The extrapolation in the new analysis was reasonable, according to Prof Tim Lenton, at the University of Exeter, UK. He said the tipping point could lead to a partial Amoc collapse, for example only in the Labrador Sea, but that this would still cause major impacts. Divlitsen said he hoped the debate would drive new research: “It’s always fruitful when you do not exactly agree.”
Prof Stefan Rahmstorf, at the University of Potsdam, Germany, said: “There is still large uncertainty where the Amoc tipping point is, but the new study adds to the evidence that it is much closer than we thought. A single study provides limited evidence, but when multiple approaches have led to similar conclusions this must be taken very seriously, especially when we’re talking about a risk that we really want to rule out with 99.9% certainty. Now we can’t even rule out crossing the tipping point in the next decade or two.”