Continuous δ13C-CH4 and δ2H-CH4 measurements in the atmosphere - data gathered at Lamezia Terme (Calabria, Southern Italy) in 2025

This dataset features the results of a measurement campaign performed between October 10th 2025 and November 7th 2025 at the CNR-ISAC Lamezia Terme (code: LMT) laboratory (Lat: 38.8774 N; Lon: 16.2364 E; Inlet elev.: 6 m AGL), relying on an extraction system built by Utrecht University, coupled to a DeltaV Isotope ratio mass spectrometer (IRMS). This takes up to 6ml of air and concentrates this cryogenically on HayeSepD, after it is converted to H2 or CO2 for the δ2H or δ13C measurements, respectively. Brass & Röckmann (2010: https://doi.org/10.5194/amt-3-1707-2010) described this system in detail. Application of this system can be found, for example, in van Es et al. (2025: https://doi.org/10.1029/2024JD043015), and comparable datasets can be found on the ICOS Data Portal (https://meta.icos-cp.eu/objects/dl8G9tfEqA6vEdySMXdA9vTa). The IRMS system at LMT measured CH4 (ppm) mole fractions, δ13C-CH4 (‰, VPDB) and δ2H-CH4 (‰, VSMOW). The results of the experimental campaign are aggregated on a hourly basis.