AN 20 - Exceptional Reproducibility from a Picarro Isotopic Water Analyzer

The ability to measure the δ¹⁸O and δD isotopic content of water has long relied on cumbersome methods that require well equipped laboratories, highly qualified technicians and frequently calibrated instruments. The advent of commercial analyzers based on Wavelength Scanned Cavity Ringdown Spectroscopy (WS-CRDS) for isotopic water measurements has opened up new possibilities for mobile laboratory and field deployable isotopic instruments. For these environments the consistency or reproducibility of data over days of operation provides tremendous savings in calibration time and effort and, perhaps more importantly, provides confidence in data collected in challenging environments. In this application note we present data from two runs of the same sample set that were measured on two consecutive days without any instrument calibration during or between the runs. The results of this study clearly confirm that the reproducibility of the Picarro system is very high and will enable additional methods development for faster and more robust studies.