Hammes et al. (2025): Soil processes govern alkalinity and cation retention in enhanced weathering for carbon dioxide removal
Jens S. Hammes, Jens Hartmann, Johannes A. C. Barth, Tobias Linke, Ingrid Smet, Mathilde Hagens, Philip A. E. Pogge von Strandmann, Tom Reershemius, Bruno Casimiro, Arthur Vienne, Anna A. Stoeckel, Ralf Steffens and Dirk Paessler, IN: EGUsphere, https://egusphere.copernicus.org/preprints/2025/egusphere-2025-5402/
Avoiding the most damaging consequences of climate change will almost certainly require pairing rapid emission cuts with large-scale carbon dioxide removal (CDR). Among the proposed CDR pathways, enhanced weathering (EW) accelerates natural mineral dissolution to convert atmospheric CO₂ into long-lived bicarbonate and carbonate reservoirs. Despite the many reported data from EW experiments, large uncertainty remains about the realisable CDR potential of applying rock materials to agricultural land. One of the relevant sinks for CO₂ is the transfer to bicarbonate alkalinity, and various EW studies have reported a wide range of results for this process. Intercomparison of these data is problematic due to the different experimental set-ups, environmental conditions as well as combinations of rock materials and soil types. In order to assess and compare the realisable CDR potential of various EW combinations, a large greenhouse experiment was set up in which 4 different soil types (7 different soil batches) were treated with 13 different feedstock materials.