Automated calibration of laser spectrometer measurements of δ O and δ H values in water vapour using a Dew Point Generator.

Rationale: Continuous measurement of stable O and H isotope compositions in water vapour requires automated calibration for remote field deployments. We developed a new low-cost device for calibration of both water vapour mole fraction and isotope composition.

Methods: We coupled a commercially available dew point generator (DPG) to a laser spectrometer and developed hardware for water and air handling along with software for automated operation and data processing.