

It’s important to remember that science is inherently conservative and doubly so for climate change Erring on the Side of Least Drama.
If you read any of the IPCC reports you’ll note they are very careful to not really provide any death estimates or anything. However, one can attempt to extrapolate a risk model from those descriptions from that we can analyze key takeaways from the WG2 report 1
The report found that climate impacts are at the high end of previous estimates
3.3 billion people about 40% of the world population, now fall into the most serious category of “highly vulnerable” ___ 1 billion people face flooding.
Based on the existential risk model, that’s 3.3 billion currently facing some level of existential risks. If the impacts remain “at the high end of previous estimates”, which they very likely will, then that’s >3.3 Billion potential deaths.
^1: using Wikipedia summary because the report is 3675 pages long and ain’t nobody got time for that^
Reference to the war of 1812, it was still ~50 years before Canada slipped the British leash but there’s some weird nationalist revisionist history surrounding it.