Ketan is correct here. For all the optimism in the slides I shared yesterday, we are not moving at the speed required to stay below 1.5C of warming. Staying below 2C of warming is still doable, but requires concerted action. I would place our current path as 2-2.5C. 1/n
https://twitter.com/KetanJ0/status/1479444489634729987
As @Peters_Glen pointed out yesterday, 1.5C is, if not mathematically impossible, certainly extremely implausible from a policy standpoint.
https://twitter.com/Peters_Glen/status/1479031770557427716?t=x1elzdSdJWm4md_vKjrUxA&s=192/n
Even net zero by 2050 looks daunting (though within our power to achieve). If I were to look at our technical & policy progress, I see us being able to achieve something close to SSP 4-3.4: Cutting emissions in half by 2050, and to zero by 2080. Worst case- IMHO is SSP2-4.5. 3/n 
SSP2-4.5 has emissions not even peaking until 2040, and dropping 75% by 2100. (Yellow line.) We can do better than that. 4/n
Where does that put us in warming? SSP4-3.4 leads to about 2.2C of warming, plus or minus some tenths of a degree. SSP2-4.5 (what I consider a worst case) leads to ~2.7C of warming, plus or minus. (Both are on the right graph.) 5/n
So that's where I see our current trajectory. Somewhere between 2.2 - 2.7C of warming (with uncertainty on top of that). I believe we can bend that curve even further, and close to 2C, with concerted effort. 2C itself is bad, in a myriad of ways. But we can survive it. 6/n
At the end of the day, there's a huge amount of work to do to decarbonize our civilization and halt warming. Technology provides us an incredible tool, but it's one we have to harness through policy and economics. We've bent the climate curve already. And we have much more to do.
(A number of these charts on climate SSPs extracted from this helpful thread by @hausfath
https://twitter.com/hausfath/status/1181707604935888897?s=20)
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