With the recent @IEA World Energy Outlook 2019 release we can compare how the IEA reference case outlooks for carbon emissions stack up against the IPCC reference scenarios - are we far off track from avoiding warming >2˚C? Thread: 1/11 
The IEA scenarios project developments in the global energy system through 2040 so we can look at CO2 emissions from energy and industry in that year across the sets of scenarios used for IPCC assessments. Thread: 2/11
Notably, the IEA Current Policies Scenario (CPS) is falling into the lowest range of the IPCC 5th Assessment projections from about 10 years ago, and the IEA Stated Policies Scenario (SPS) is lower than all the IPCC reference case ranges. Thread: 3/11
The IPCC 5th Assessment scenario database included some illustrative RCP8.5, RCP6.0 and RCP4.5 scenarios - how do the IEA scenarios stack up against those? The IEA CPS is tracking under RCP4.5, and the IEA SPS is well below RCP4.5. Thread: 4/11
With this in mind, it is fair to say that the global energy system today, as modeled by IEA, is tracking much closer to 2˚ of warming this century than previously thought. Thread: 5/11
RCP4.5 is generally thought to exceed 2˚, but expected to lead to less than 2.5˚ of warming this century. Thread: 6/11
Why are the recent IEA scenarios projecting much lower CO2 emissions than IPCC scenarios? One clue is in the composition of the global energy system. Thread: 7/11
Here’s a plot of the IEA reference scenario outlooks for global coal in 2040 vs. IPCC scenario ranges. The IEA reference cases are lower than 90% of all the IPCC scenarios, and the IEA SPS is lower than 95% of the IPCC scenarios. Thread: 8/11
The IEA reference scenarios are showing lower outlooks for CO2 emissions and global coal use than IPCC scenarios, including those in the SSP database informing the upcoming IPCC 6th Assessment. Is the IEA outlook possibly more accurate? Thread: 9/11
As my co-author and I argued here sciencedirect.com/science/articl… and here iopscience.iop.org/article/10.108… the energy-economy models used to create these IPCC scenario ranges are biased toward unrealistically favorable economics for high-carbon energy projects. Thread: 10/11
Conclusion: IEA scenarios are a more realistic projection of the global energy system’s current ‘baseline’ trajectory; showing we are far from RCP8.5 & RCP6.0. World currently tracking between RCP4.5 & lower climate change scenarios - consistent with 1.5˚ to 2.5˚C. Thread: 11/11
Thread Appendix: If we truly are so far off-track from RCP8.5 will that scenario be prominently featured alongside other scenarios in the next IPCC Assessment in a way that implies equal likelihood among all the scenarios?
