Open-path measurement of stable water isotopologues using mid-infrared dual-comb spectroscopy
Daniel I. Herman,Griffin Mead,Fabrizio R. Giorgetta,Esther Baumann,Nathan A. Malarich,Brian R. Washburn,Nathan R. Newbury,Ian Coddington,and Kevin C. Cossel
Daniel I. Herman
Spectrum Technology and Research Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States of America
Department of Physics, University of Colorado Boulder, Boulder, Colorado 80309, United States of America
Griffin Mead
Spectrum Technology and Research Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States of America
Fabrizio R. Giorgetta
Spectrum Technology and Research Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States of America
Department of Physics, University of Colorado Boulder, Boulder, Colorado 80309, United States of America
Esther Baumann
Spectrum Technology and Research Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States of America
Department of Physics, University of Colorado Boulder, Boulder, Colorado 80309, United States of America
Nathan A. Malarich
Spectrum Technology and Research Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States of America
Brian R. Washburn
Spectrum Technology and Research Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States of America
Department of Physics, University of Colorado Boulder, Boulder, Colorado 80309, United States of America
Nathan R. Newbury
Spectrum Technology and Research Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States of America
Ian Coddington
Spectrum Technology and Research Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States of America
Measurements of the isotope ratio of water vapor provide information about the sources and history of water vapor at a given location, which can be used to understand the impacts of climate change on global water use. Here, we demonstrate a new method for measuring isotope ratios over long open-air paths, which can reduce sampling bias and provide more spatial averaging than standard point sensor methods. We show that this new technique has high sensitivity and accuracy.
Measurements of the isotope ratio of water vapor provide information about the sources and...