Data from: Degassing emissions in a temperate hydropower reservoir driven by seasonal stratification patterns but highly sensitive to discharge variability

Hydropower reservoirs contribute to methane (CH4) and carbon dioxide (CO2) emissions, as do all aquatic ecosystems. Unique to hydropower reservoirs are degassing emissions that occur when deepwater intakes move water with high CH4 and CO2 concentrations through turbines, leading to release of these gases. However, very few studies from hydropower reservoirs have empirically measured seasonal variability in degassing fluxes of both CH4 and CO2. We collected monthly data to calculate degassing emissions in temperate Douglas Reservoir (Tennessee, USA) from 2023-2024. This data collection include monthly measurements of CH4 and CO2 gas concentrations in the forebay and tailwater, monthly discharge corresponding to sampling dates, calculated CH4 and CO2 degassing emissions, as well as ancillary sonde and water chemistry taken at the surface and bottom of the reservoir forebay.