ARCHER2 Calendar February 2025

Modelling hydrogen deposition: assessing climate impacts of interactive methane and hydrogen

Dr Megan Brown, Yufus Hamied Department of Chemistry, University of Cambridge

Atmospheric hydrogen indirectly contributes to climate change by extending the lifetime of methane and increases the production of other greenhouse gases. Hydrogen lifetime in the atmosphere is poorly constrained; two main ways it is destroyed is by chemical reactions (30%) and soil uptake from microbes (70%). The soil uptake has a large uncertainty (+/-60%), and is important for determining the proportion of hydrogen emissions which cause chemical feedbacks impacting methane. We implemented a two-layer soil deposition scheme into a global climate model (Unified Model) to capture the seasonal and global distribution of atmospheric hydrogen. This figure shows the global hydrogen uptake from the final year of a 20-year simulation which has been run on ARCHER2, with an underlayer of topography. We've combined this soil uptake scheme with interactive methane to further understand the impact of hydrogen on methane and its potential greenhouse gas effects.

This image was published on the February page of the ARCHER2 2025 printed calendar.