The thing people really have to understand about climate change is how unprecedented the impact of many of the changes coming are. I mean if you look at a globe you should immediately see that most of Europe is North of the United States. The reason it's comfortable to live there an agriculture is possible is the Gulf Stream.

But forget the Gulf Stream, you should learn more about the Atlantic meridional overturning circulation (AMOC)[0], which also could be shut down. There is geological evidence that such a shut down would turn the Atlantic ocean anoxic, literally turning the ocean toxic.

This isn't some wacky, doomer fantasy scenario, this has happened multiple times in Earth's history when CO2 levels and temperatures have risen and been responsible for multiple mass extinction events[1]. It's also worth pointing out that the AMOC is already showing evidence of weakening [2]

A good overview of this paleontologist Peter Ward's Under a Green Sky.

0. https://en.wikipedia.org/wiki/Atlantic_meridional_overturnin...

1. https://en.wikipedia.org/wiki/Anoxic_event

2. https://www.science.org/doi/10.1126/sciadv.aaz4876