HMN 2025: How Inconsistent reporting by corporations results in underestimation of methane’s local weather affect

Companies around the globe are underestimating their complete greenhouse fuel footprints due to inconsistent accounting requirements for methane emissions, finds a brand new study by researchers from UCL and Imperial College London.

The new study, published in Nature Communications, discovered that methane emissions are being underreported by at the least the equal of between 170 million and three.3 billion tons of carbon over a decade, relying on the metric utilized in calculating the shortfall.

This implies that annually, on common, corporations around the globe have doubtlessly underestimated their carbon footprint by as a lot in complete because the annual carbon emissions of the UK in 2022. This represents a major methane emissions hole that would value between $1.6 billion (£1.3 billion) and $40 billion (£32 billion) to repair.

Lead Author Dr. Simone Cenci (UCL Bartlett School of Environment, Energy & Resources) mentioned, “The cumulative emission hole now we have documented on this work exhibits how essential it’s to standardize the reporting of methane emissions. Methane is a potent greenhouse fuel and step one in the direction of correctly addressing its impact on local weather is to make it possible for it is accounted for correctly.

“Adopting a worldwide commonplace is in precept straightforward for corporations because it primarily solely requires the adjustment of some conversion components when calculating their greenhouse fuel footprint. However, it requires international coordination as corporations are at present usually topic to fragmented rules.”

Methane is a potent greenhouse fuel that contributes to international warming at ranges akin to carbon dioxide. Though methane is emitted in a lot smaller portions than carbon dioxide, it is extra environment friendly at trapping warmth within the ambiance. However, methane can also be short-lived within the ambiance, with a half-life of solely about 10 years versus 120 years for carbon dioxide.

How a lot complete warmth a greenhouse fuel traps is known as its Global Warming Potential (GWP) and measured in CO₂ equal items, or the quantity of carbon dioxide fuel that may trigger the identical quantity of warming. Because of methane’s brief lifespan, the conversion to CO₂ is just not simple and debate persists about how greatest to signify it by way of carbon dioxide.

If methane’s affect is calculated over 20 years (GWP-20), it is about 80 occasions stronger than carbon dioxide as a result of that is the timeframe earlier than most of it has dissipated. However, gauged over 100 years (GWP-100) extra of the methane has damaged down so it is solely about 28 occasions as potent.

For corporations estimating and reporting their greenhouse fuel footprint, this lack of harmonization could cause confusion and inaccuracies, as there is no legally binding steerage or consensus for which commonplace to make use of.

In this study, the researchers compiled and analyzed methane emissions from a pattern of two,846 consultant corporations throughout a variety of financial sectors and international locations. They discovered the conversions utilized by the businesses are largely inconsistent with the rules of most present carbon accounting requirements that suggest the identical GWP-100 metric as the newest Intergovernmental Panel on Climate Change (IPCC) Assessment Report.

To see how a lot methane emissions may be underreported, the crew substituted the businesses’ varied accounting conversions with the usual GWP-100 system prompt by the IPCC. Over the ten years from 2014 to 2023, methane emissions have been underreported by the equal of about 170 million tons of carbon dioxide.

When they harmonized all reporting to the stricter GWP-20 commonplace, advocated by some local weather scientists and utilized in some US jurisdictions, they discovered that over the identical decade, methane emissions had been underestimated by the equal of about 3.3 billion tons of carbon dioxide.

The crew additionally analyzed the financial value of correcting the underrepresented carbon footprints. Based on carbon costs from emission buying and selling schemes throughout the globe, the cumulative value to corporations over the review’s ten years would complete about $1.6 billion (£1.3 billion) to align all international corporations with the GWP-100 commonplace, and about $40 billion (£32 billion) to align with the stricter GWP-20 commonplace. Companies within the vitality, utilities and materials sectors would face the most important prices as a result of they’re the most important industrial emitters of methane.

The authors word that even with their prompt corrections, complete methane emissions are nonetheless being underestimated, as their calculations solely centered on emissions instantly produced by the businesses they analyzed. Other downstream emissions, similar to that which come from bought merchandise, weren’t included, and are probably vital contributors as nicely, notably within the vitality sector.