the crazy thing is, we have very little concrete evidence of what the fuck will happen, no one's ever taken the climate for a ride like this. we're literally unprecedented in the annals of disaster lol.

but the source for that was:

There is a consensus the AMOC keeps northern and western Europe warmer than it would be otherwise,[17] with the difference of 4 °C (7.2 °F) and 10 °C (18 °F) depending on the area.

https://en.wikipedia.org/wiki/Atlantic_meridional_overturning_circulation