20 March, 2026

Amid the number crunching and reduction pathways, it’s important to keep sight of the ultimate value of GHG measurement and management: to minimise harm to the delicate balance of life on earth. 

Understanding the long and complex causal chain between human activities that release emissions and the harm that’s created by them is a hugely important part of this endeavour. And herein lies both the strength of emissions accounting (an attempt to quantify the impact of these activities) but also its weakness (the reduction of a lot of complexity into a simple output). 

This relies on assumptions, and one of the most significant of these is the equivocation of the variety of GHGs into a single metric, CO2e, which converts GHGs into the equivalent impact of CO2 over a 100-year timescale. Understanding the issues with this gets technical quickly (see this this blog post  for a good rundown) but in short: while CO2 lasts thousands of years in the atmosphere, methane is broken down in only twelve. By focusing on the longer timescale, we mask the short, intense impact of methane and other ‘superpollutants’ in the shorter term. Then there’s also the fact that the 100 year timescale is far from aligned with business decision-making. 

This has been a topic of debate among the scientific community, but it hasn’t filtered through to corporate emissions management. Or not yet.  

There’s no simple answer for how to better reflect the varied impact of different emissions in either calculation or management. But it is clear that we need to better understand how to treat superpollutants, particularly in energy, waste and agriculture. So we’re very pleased to see the launch of the Super Pollutant Action Alliance, which will build on research and existing coalitions to embrace this nuance and look forward. Surely an essential step for a more complete and effective response to GHGs. 

By Patrick Bapty