Nitrous oxide and methane concentrations and air-sea fluxes in undersampled areas of the Mediterranean basin

This dataset provides a one-year time series of monthly surface water concentrations of nitrous oxide (N2O) and methane (CH4), along with ancillary biogeochemical variables (temperature, salinity, and dissolved oxygen). Sampling was conducted at eight coastal stations distributed across the Mediterranean littoral, including sites in Spain, Morocco, Lebanon, and Turkey, to capture longitudinal and seasonal variability. Dissolved gas concentrations were determined by static headspace equilibration followed by gas chromatography analysis. Additionally, the dataset includes calculated monthly air-sea gas fluxes (F) derived from the bulk parameterization (Wanninkhof, 2014). This dataset serves as a supplement to the manuscript: de la Paz et al. (submitted to ESSD, 2026). For detailed information regarding sensor calibration, analytical precision, and flux calculation parameters, please refer to the aforementioned publication.