THREAD
There is a new comment out calling for the use of more extreme scenarios.
I agree with many arguments made, the problem is, the literature is full of extreme scenarios...
(this thread is a little tongue-in-check, but also serious)
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rdcu.be/b1OcE
There is a new comment out calling for the use of more extreme scenarios.
I agree with many arguments made, the problem is, the literature is full of extreme scenarios...
(this thread is a little tongue-in-check, but also serious)
1/
rdcu.be/b1OcE
IAMs depend "on the appearance in a puff of smoke of a carbon-sucking fairy godmother" nature.com/news/talks-in-…
Nearly all scenarios have extreme negative emissions, perhaps we could have something more 'normal'?
science.sciencemag.org/content/354/63…
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Nearly all scenarios have extreme negative emissions, perhaps we could have something more 'normal'?
science.sciencemag.org/content/354/63…
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Scenarios seem rather keen on coal (this was the start of the RCP8.5 debate).
Even those consistent with 2°C can have rather extreme coal, even a return to coal (with CCS). I don't know, but I would call a return to coal rather extreme?
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Even those consistent with 2°C can have rather extreme coal, even a return to coal (with CCS). I don't know, but I would call a return to coal rather extreme?
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Scenarios love CCS, to a rather extreme level. 10, 20, 30 GtCO₂/yr CCS is not unheard of. This figure is CCS in scenarios that exceed 3°C of warming! Imagine CCS for 1.5°C or 2°C...
There are a few scenarios without CCS, they are the exception (extremes), not the rule.
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There are a few scenarios without CCS, they are the exception (extremes), not the rule.
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Most scenarios implement global carbon prices, harmonised, globally. This means there is rather disruptive changes, for example, with coal declining ~80% by 2030 *globally*.
I would call a global uniform carbon price in 2020 rather extreme, but that is standard fair.
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I would call a global uniform carbon price in 2020 rather extreme, but that is standard fair.
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Not a day goes past in my timeline when someone doesn't point out that renewable costs are way off in most models
@NB_pik also points out that models are not so good on integration costs & other aspects either
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@NB_pik also points out that models are not so good on integration costs & other aspects either
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I could go on at infinitum.
Basically, most days I feel like I am screaming into an empty void: Can. We. Please. Have. Some. Normal. Scenarios.
Now there is a call for *more* extreme scenarios?
Ok, now to where I agree with the paper...
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Basically, most days I feel like I am screaming into an empty void: Can. We. Please. Have. Some. Normal. Scenarios.
Now there is a call for *more* extreme scenarios?
Ok, now to where I agree with the paper...
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There are many big gaps in the literature.
Most models seem rather weak on demand modelling. Most mitigation happens on the supply side, not the demand side. The LED scenario fills that gap (one scenario).
rdcu.be/bPgJr
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Most models seem rather weak on demand modelling. Most mitigation happens on the supply side, not the demand side. The LED scenario fills that gap (one scenario).
rdcu.be/bPgJr
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Models are very conservative on population assumptions (not many outliers).
GDP growth is very high compared to history, no degrowth scenarios (also see doi.org/10.31235/osf.i…)
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GDP growth is very high compared to history, no degrowth scenarios (also see doi.org/10.31235/osf.i…)
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While I agree with the authors that there is a need to explore extremes (& that should be supported & encouraged), I also think that the modelling community has an outlier problem that it has yet to dealt with.
Glass half full, glass half empty?
rdcu.be/b1OcE
10/10
Glass half full, glass half empty?
rdcu.be/b1OcE
10/10
