Hydrogen emissions from leakage, venting and purging leads to global warming, new research confirms. To take advantage of the potential benefits of switching from fossil fuel systems to hydrogen, we need to keep emissions at a minimum, and doing so will depend on the development of new instruments that can detect even small leaks, allowing us to minimize them in the future.

A new paper published this summer in the journal Communications Earth and Environment uses five different climate models that show consistent results on hydrogen’s global warming potential at the 20, 100, and 500 year ranges. These results align with other recent studies.

In the new study, six groups of scientists reached the conclusion that hydrogen has 12 times the warming power of CO2 pound for pound over 100 years after release. It’s even more powerful in the first 20 years, when it packs more than 35 times the climate warming of CO2.

Hydrogen in the atmosphere behaves differently than CO2. While it doesn’t trap heat itself, the roughly one quarter of hydrogen emissions that isn’t taken up by microbial activity in soils leads to a chain of chemical reactions in the atmosphere that increase the amounts of other potent short-lived GHGs (methane, ground level ozone and upper atmosphere water vapor). These warming impacts are short-lived, both because hydrogen’s lifetime is short, and because its indirect effects through increasing GHG amounts only last a few decades. Thus, it’s important to evaluate its warming impacts on both short- and long-term warming potential timescales.