Measuring and Modeling of Methane Emissions from Thermokarst Ponds in the Arctic

Project A1 builds on the combination of strong expertise in both empirical field and laboratory measurements and dynamic Earth system modelling. Within her PhD project, A1-participating researcher Zoé Rehder investigated the methane emission dynamics of thermokarst ponds in Siberian permafrost landscapes. Based on an extensive field dataset, she identified the key processes that determine methane concentrations in various pond types (Rehder et al., 2021). Joint work of Zoé Rehder with A1-PhD student Lutz Beckebanze applied eddy covariance measurements of land-atmosphere methane fluxes and showed that the shorelines of ponds can be hotspots of methane emissions (Beckebanze et al., 2022). Based on the empirical data analysis, Zoé Rehder designed, established and validated the new process model MeEP. MeEP simulations under warming scenarios show that strong increases of methane emissions from arctic permafrost landscapes have to be expected, especially due to indirect effects of warming on the ponds’ methane turnover through enhanced plant productivity (Rehder et al., in prep.).