Normally, when we talk about the climate impact of a material, we are talking about ‘carbon equivalent emissions’. CO2e is a measurement that normalises different emissions types like methane, nitrogen and carbon dioxide into one measurement, but it’s important to understand how each of these greenhouse gases contribute individually, because they function differently. The methane associated with rearing cattle and sheep in fashion supply chains for leather and wool is caused by enteric fermentation, the process where these ‘ruminant’ animals digest food through multiple stomachs. As a result, they breathe out, pass and belch methane into the atmosphere.
Vogue: How much does fashion need to reduce its methane footprint by, and how much time does it have to do so?
According to Nasa, 30 per cent of global warming since the Industrial Revolution is due to methane emissions specifically. Our calculations show that the fashion industry’s current estimated methane footprint is 8.3 million tonnes per year. The Global Methane Pledge, which has been endorsed by over 150 countries as well as the United Nations, states that we must cut methane emissions by 30 per cent before 2030 in order to curb the worst of the climate crisis and align with the Paris Agreement. That’s compared to a 2020 emissions baseline, so we are five years in.
However, until now, there has been no estimated methane footprint of the fashion industry. That means that, as the fashion industry has grown, it is likely that its methane footprint has too, so we may need to reduce methane by even more than a third, but we simply don’t have the data to support that. At an absolute minimum though, we need a 30 per cent reduction within the next five years to meet this target. That’s very little time to make such a big change, but science isn’t interested in what is practical for businesses. What we can say is that every brand has an obligation to put every effort into aligning with the Global Methane Pledge.
Methane mitigation is an emergency brake against the climate crisis that we must pull now, so that we give ourselves more time to continue slashing carbon dioxide emissions, reducing water inefficiencies and so on.
Vogue: This is fashion’s first methane footprint. How did you go about calculating it, and were there any challenges or limitations?