Increasingly scenario users are interested in 'where we are heading' as a baseline, rather than no climate policy scenarios (light grey) & SSP5-85 (RCP85).
Current policies may take the world to ~3.2°C (10-90% range 2.3-4.4°C due to climate uncertainties), which is much less than >5°C in SSP5-85.
The bold lines are from the NGFS scenarios used by financial institutions for 'stress testing', the thin lines are from IPCC SR15.
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Another organisation that has been doing work on 'where we are heading' is the @climateactiontr, which has quite consistent numbers as the NGFS (though quite different methods).
* NGFS is based on modelling
* CAT is more a statistical approach
The IEA has been doing 'where we are heading' type scenarios for years, and what we used in our commentary nature.com/articles/d4158…
Though, the IEA gets flak for this. The solar critiques are aimed at this scenario. Some users don't like 'where we are heading' scenarios...
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An important policy-relevant community is those "who want better predictions about what might happen in the world as a whole" nature.com/articles/d4158…
Which is sort of obvious, but still needs Nature commentaries to make the obvious point(s) nature.com/articles/d4158…
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Which brings me to @HectorPollitt's point, 'will anything change'?
Well, slowly at best. After 10 years of complaining, IAMs are only now starting to incorporate more critical thinking on CDR (for example).
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We are certainly seeing a shift away from "no climate policy" baselines, certainly in the energy system modelling community. I think there will be at least a 5-10 year lag in the climate modelling community (& there are other reasons for using SSP5-85).
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This question is ambiguous: "How high above pre-industrial levels do you think average global temperature will rise between now and 2100?"
* ...pre-industrial... between "now and 2100"?
* Where we are currently heading or where we could head? This is largely a policy question?
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One of the key arguments that Norway uses to continue oil & gas developments, is that under BAU it is expected that oil & gas production will decline in line with <2°C scenarios, even with continued investment.
Let's look closer at these projections & reality...
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Here is the projections from the 2003 report from the petroleum agency.
In reality (tweet 1) there was a dip around 2010, but production is now up around 250 million cubic again.
The forecast was totally & utterly WRONG!
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In 2011 there was a forecast for an increase in production to 2020, but then a decline. This is probably since they started to put the Johan Sverdrup field on the books.
The increase in production was way too low, again, they got it wrong.
CO2 emissions by fossil fuel:
* We thought coal peaked in 2014. No, & up another 1.1% in 2023
* Oil up 1.5%, on the back of a 28% increase in international aviation & China, but oil remains below 2019 level. 🤞
* Has the golden age of gas come to an end thanks to Russia?
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By top emitters:
* China up 4.0% & a peak this year would be a surprise
*US down 3.0%, with coal at 1903 levels
* India up 8.2%, with fossil CO2 clearly above the EU27
* EU27, down 7.4% with drops in all fuels
* Bunkers, up 11.9% due to exploding international aviation
Is the new @DrJamesEHansen et al article an outlier, or rather mainstream?
At least in terms of the key headline numbers, it seems rather mainstream, particularly if you remember most headline key numbers have quite some uncertainty!