Yes, my mistake.
DB2
An AMOC shutdown or even a substantial weakening would significantly impact the global economy and add fuel to the current complex political landscape. We don’t want it to happen. The previous IPCC report concluded it is very unlikely this century. Their argument is based on the spread of estimates of AMOC shutdown in the graph below, showing shutdown vs. temperature change. We’re likely to blow through 2ºC warming around mid-century. The SSP2-4.5 Intermediate Scenario projects 2.1°C–3.5°C by 2100. The IPCC graph then says at 3°C warming we’re starting to reach a 10% probability of a “Substantial Weakening”.
The concern is that the recent studies suggest the likelihood might be higher than previously estimated. Just how unknown is the AMOC shutdown unknown? Look how broad the uncertainty is in the graph above. Look how close we are to the thresholds. Add some more uncertainty to the uncertainty and the likelihood can easily be 20%-30% instead of 10%.
I like to ask, “Do you feel lucky?” At 10%, I think, yeah, I feel lucky. At 25%, with the stakes this high, not so much.
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