An Appeal to UN IPCC

 

Dear reader, if you have the ability to influence the UN IPCC, please help. There are too many emission data sources and versions publicly available today. Some of them are more highly ranked than others by search engines, yet they may not utilise the same methodology as the latest IPCC reports and thus, simply cannot offer the needed coherency and consistency when addressing carbon mitigation calls by the IPCC.

 

Even worse, I have discovered that the latest IPCC AR6 reports have decided to use a slightly different emission dataset methodology compared to the previous AR5 reports, including how the emission data sources are compiled, as well as the GWP-100 values for conversion of non-CO2 gases. I am simply exhausted trying to keep up with the changes! The latest AR6 Annex II (Part III) that details these subtle methodology changes is still subject to final edits so I will not elaborate at this point.

 

I found this out the hard way. I hope no one else has to. This is very damaging to the world even as one already struggles to fight climate change. Emissions are always tracked to a baseline year but literally everyone in the world now is possibly using a different methodology and will be a disaster for the good people trying to reconcile the Global Carbon Budget.

 

To solve this problem, the IPCC must come out with its own public visualisation tool for world emissions from perhaps 1970 onwards, conforming to its own methodology, available for everyone to use. There can be and should be no room for a second source moving forward to put a stop to global confusion.

Emissions Data used by UN IPCC AR5 WG3 report (Year 2010)

(To aid coherency and consistency, core historic data presented throughout the IPCC AR5 reports uses the same sources and applied the same methodologies and standards.)

 

• CO2 emissions from fossil fuel combustion are taken from IEA (2012c). IEA Data Services
• Remaining CO2 and non-CO2 GHG emissions are taken from EDGAR (JRC / PBL, 2013). EDGAR website
• Following general scientific practice, 100-year Global Warming Potential Values (GWPs) from the IPCC Second Assessment Report (SAR) (Schimel et al., 1996) are used as the index for converting GHG emissions to common units of CO2-eq emissions in EDGAR. The lower GWP-100 values as defined by SAR are used in AR5 reports despite upward revisions made to the GWP-100 values with every assessment report update since SAR. GHG Protocol GWP-100.
• Full UN IPCC mapping of emission sectors to sources in A.II.9.1

Overview of Carbon dioxide removal (CDR) methods and their estimated ranges of costs and potentials in 2030 by UN IPCC AR6 WG3 report (Year 2022)

 

In general, one may use the figure below to quickly see all the Carbon dioxide removal (CDR) methods (referred to as “Mitigation options” in the figure) available in one’s own sector, as identified by the UN IPCC in their AR6 WG3 Report. 

 

Source: IPCC AR6 WG3 Report.

 

Focus on the mitigation options that have long horizontal bars, as these options are already known to carry the highest potential contribution for net emission reductions.

 

The error bars display the full ranges of the estimates for the total mitigation potentials. 

 

Sources of uncertainty for the cost estimates include assumptions on the rate of technological advancement, regional differences, and economies of scale, among others. Those uncertainties are not displayed in the figure.

 

(note this section on mitigation options is marked as “subject to copyedit” in IPCC AR6 WG3 Report, as of 14 Apr 2022)