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Paper 1: "[E]xisting infrastructure will emit ~658GtCO₂ ... more than the entire remaining carbon budget [for] 1.5°C"
Paper 2: "[I]f carbon-intensive infrastructure is phased out at the end of its design lifetime ... there is a 64% chance [warming] remains below 1.5°C"
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Paper 2: "[I]f carbon-intensive infrastructure is phased out at the end of its design lifetime ... there is a 64% chance [warming] remains below 1.5°C"
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Paper 1: nature.com/articles/s4158…
Paper 2: nature.com/articles/s4146…
Why do these papers get different answers, basically, carbon budgets & non-CO₂?
@chrisroadmap explains here
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Paper 2: nature.com/articles/s4146…
Why do these papers get different answers, basically, carbon budgets & non-CO₂?
@chrisroadmap explains here
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Short answer: But, it is all within uncertainties...
I think the way carbon budgets are often expressed, "66% chance below X°C" hides the uncertainty, much better to show the range of outcomes (as is done for the ECS, etc)
rdcu.be/bHT2C
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I think the way carbon budgets are often expressed, "66% chance below X°C" hides the uncertainty, much better to show the range of outcomes (as is done for the ECS, etc)
rdcu.be/bHT2C
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You can't express a probability distribution with one number, you need at least two numbers (e.g., the mean & standard deviation).
It is better to say the carbon budget for 1.5°C is 420-840GtCO₂ (33-66%), then to say it is 66% chance below 420GtCO₂.
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It is better to say the carbon budget for 1.5°C is 420-840GtCO₂ (33-66%), then to say it is 66% chance below 420GtCO₂.
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Scenarios that are 66% below 2°C in MAGICC are actually below 1.5°C in FAIR (both Simple Climate Models).
While these uncertainties are beyond carbon budgets and relate to non-CO₂, it is a useful reminder that carbon budgets will go up & down as models are improved.
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While these uncertainties are beyond carbon budgets and relate to non-CO₂, it is a useful reminder that carbon budgets will go up & down as models are improved.
5/5
