Articles | Volume 16, issue 22
https://doi.org/10.5194/amt-16-5697-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-16-5697-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
| 
28 Nov 2023
Research article | Highlight paper |
| 28 Nov 2023
| 28 Nov 2023
Ground-to-UAV, laser-based emissions quantification of methane and acetylene at long standoff distances
National Institute of Standards and Technology, Spectrum Technology and Research Division, Boulder, CO 80305, USA
Eleanor M. Waxman
National Institute of Standards and Technology, Spectrum Technology and Research Division, Boulder, CO 80305, USA
Eli Hoenig
National Institute of Standards and Technology, Spectrum Technology and Research Division, Boulder, CO 80305, USA
Daniel Hesselius
Integrated Remote and In-Situ Sensing (IRISS), University of Colorado, Boulder, CO 80305, USA
Christopher Chaote
Integrated Remote and In-Situ Sensing (IRISS), University of Colorado, Boulder, CO 80305, USA
Ian Coddington
National Institute of Standards and Technology, Spectrum Technology and Research Division, Boulder, CO 80305, USA
Nathan R. Newbury
National Institute of Standards and Technology, Spectrum Technology and Research Division, Boulder, CO 80305, USA
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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.
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This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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Most methane emissions during the life cycle of beef cattle occur during the grazing phase. Measuring methane in grazing systems is difficult due to the high mobility and low density of animals. This work investigates if dual-comb spectroscopy can measure methane emissions from small cattle herds. An enhancement of 10 nmol mol-1 methane above the atmospheric background was measured, equivalent to 20 head located 60 m away. The calculated methane flux was within 5 % of the actual release rate.
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
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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.
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This paper describes data collected by uncrewed aircraft operated by the University of Colorado Boulder and Black Swift Technologies during the Lower Atmospheric Profiling Studies at Elevation – A Remotely-piloted Aircraft Team Experiment (LAPSE-RATE) field campaign. This effort was conducted in the San Luis Valley of Colorado in July 2018 and included intensive observing of the atmospheric boundary layer. This paper describes data collected by four aircraft operated by these entities.
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Executive editor
As the Editor states does this manuscript describe application of long-path absorption spectroscopy to detection of gas leak plumes. The technique uses an unmanned aerial vehicle (UAV) carrying a retroreflector as the endpoint of the absorption path, which allows for rapid discovery of plume location and quantification of plume cross section for emissions rate determination. The technique works at a safe standoff distance and through the use of the UAV doesn't need two fixed end locations. It would be of interest to many seeking to find and quantify gas leaks, which is important for safety and minimizing greenhouse gas and reactive gas emissions.
As the Editor states does this manuscript describe application of long-path absorption...
Short summary
Measurements of the emission rate of a gas or gases from point and area sources are important in a range of monitoring applications. We demonstrate a method for rapid quantification of the emission rate of multiple gases using a spatially scannable open-path sensor. The open-path spectrometer measures the total column density of gases between the spectrometer and a retroreflector mounted on an uncrewed aerial vehicle (UAV). By scanning the UAV altitude, we can determine the total gas emissions.
Measurements of the emission rate of a gas or gases from point and area sources are important in...
