How do we measure greenhouse gas emissions? Part 2

Now we know about GWPs and CO2e, where did that global greenhouse gas emissions figure of 54.59 Gt of CO2e come from? And more importantly, how can we have confidence that it is an accurate figure? Before we get into the details take a look at this short video from the United Nations Environment Programme.

The key point is that a country’s total greenhouse gas emissions are calculated bottom up - information on the types of activity in a country’s economy is are combined with data on the emissions typically produced by those activities to arrive at an estimate. The International Panel on Climate Change (IPCC) provides guidelines on how those calculations should be made so that they are comparable between countries.

Under the original United Nations Framework Convention on Climate Change (UNFCCC), a country’s obligation to report their greenhouse gas emissions varied depending on their status as a developed or developing country. Developed countries were required to report their greenhouse emissions annually, while developing countries were only required to report every three or four years. These reports could be reviewed by the UNFCCC.

The Paris Agreement introduces an enhanced transparency framework which will require all countries to include their greenhouse gas emissions in a Biennial Transparency Report from the end of 2024. In theory more data is a good thing, however there are concerns that developing countries lack the capacity to reliably report their emissions.

A 2021 investigation by the Washington Post claimed that countries were underreporting their emissions to the tune of 8.5-13.3 billion tonnes a year, a material amount that would mean the scale of the challenge we face is even bigger than we thought.

There clearly are challenges in ensuring the data submitted by countries is as accurate as possible, but one thing is certain regardless, greenhouse gas emissions need to start going down fast - and as we will see in the next post they are still going up.