A multi-model assessment of the Global Warming Potential of hydrogen

• Published in: Communications earth & environment Vol. 4; no. 1; pp. 203 - 12
• Main Authors: Sand, Maria, Skeie, Ragnhild Bieltvedt, Sandstad, Marit, Krishnan, Srinath, Myhre, Gunnar, Bryant, Hannah, Derwent, Richard, Hauglustaine, Didier, Paulot, Fabien, Prather, Michael, Stevenson, David
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group 07.06.2023; Springer Nature; Nature Portfolio
• Subjects: Atmospheric chemistry; Atmospheric models; Chemical reactions; Climate change; Climate change mitigation; Fossil fuels; Global warming; Greenhouse effect; Greenhouse gases; Hydrogen; Hydrogen production; Hydroxyl radicals; Methane; Ozone; Photochemicals; Sciences of the Universe; Stratosphere; Water vapor
• ISSN: 2662-4435; 2662-4435
• DOI: 10.1038/s43247-023-00857-8

Abstract With increasing global interest in molecular hydrogen to replace fossil fuels, more attention is being paid to potential leakages of hydrogen into the atmosphere and its environmental consequences. Hydrogen is not directly a greenhouse gas, but its chemical reactions change the abundances of the greenhouse gases methane, ozone, and stratospheric water vapor, as well as aerosols. Here, we use a model ensemble of five global atmospheric chemistry models to estimate the 100-year time-horizon Global Warming Potential (GWP100) of hydrogen. We estimate a hydrogen GWP100 of 11.6 ± 2.8 (one standard deviation). The uncertainty range covers soil uptake, photochemical production of hydrogen, the lifetimes of hydrogen and methane, and the hydroxyl radical feedback on methane and hydrogen. The hydrogen-induced changes are robust across the different models. It will be important to keep hydrogen leakages at a minimum to accomplish the benefits of switching to a hydrogen economy.