To say "the remaining carbon budget for 1.5°C is 440 GtCO₂" [add favorite number] is highly misleading

Taking a narrow 67–33% range, the value is 230–670 GtCO₂, but full range (left) could be −1000 - 2000 GtCO₂... (yes, could be negative or huge)

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https://t.co/T9GvpoH0l8

When I wrote "studies ranging from −100 to about 800 GtCO₂" back in 2018 I was being very conservative (there were no full uncertainty analyses then) https://t.co/KhyA1rYpDJ

Good to see papers (now) being much more explicit about the uncertainty & range...

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I have problems with the remaining carbon budgets presented as a single number, instead of a range. Is there any other climate variable presented as a one-sided probability? The ECS, eg, is presented as a range.
https://t.co/KhyA1rYpDJ

Good to see the authors use ranges!

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The uncertainties on remaining carbon budgets are huge. Let that sink in.

There is a decent chance the remaining carbon budget for 1.5°C is negative... (ie, too late)

[The uncertainties here are 33-66%, IPCC would usually take "likely" which is more like 16-84%]

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Many of these issues were discussed by me https://t.co/KhyA1rYpDJ & @Oliver_Geden https://t.co/Kj7heJTALN

Back in 2016 I raised many of the same issues: https://t.co/bjOnjQWOqc

[I guess I should publish articles & not commentaries, as perhaps people would read them...]

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