"Penn and Deutsch looked at the consequences of several scenarios, from global warming remaining at the minimum expectation to high emission scenarios that would result in 32 degrees Fahrenheit of warming during the next three hundred years."<p>32 degrees Fahrenheit (17.8 degrees Celsius) is far beyond what the latest IPCC report considers likely. The AR6 report gives the likely Equilibrium Climate Sensitivity (eventual temperature increase from doubling of CO2) as 2.5-4.0 C. The response to CO2 is roughly logarithmic, so the effect of each doubling is about the same. So 17.8 Celsius corresponds to between 4.5 and 7.1 doublings. Current CO2 levels are less than double pre-industrial levels, and it is very, very unlikely that we will ever get to 4.5 doublings.
> Their research, published today in Science, warns that failing to reduce fossil fuel emissions will set Earth’s oceans on track for a mass extinction within the next 300 years.<p>Within the next 300 years, we hopefully will be able to terraform Mars. We should also have technology to be able to suck carbon out of the atmosphere. We may also be at the point where we can build and deploy massive solar shields in space. Trying to predict catastrophe 300 years in the future is very naive.
Isn't one already happening, on land and in the oceans?<p>I don't think we need to wait 300 years and for a bunch more warming, the future is already here.