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Joseph T. Hodges, Oleg L. Polyansky, Katarzyna E. Bielska, Melanie C. Ghysels, Lorenzo Lodi, N Zobov, Jonathan Tennyson
The atmospheric concentration of carbon dioxide (CO2), with its consequences for the greenhouse effect and climate change, is being closely monitored by a variety of space-borne and ground-based remote sensing experiments. These experiments require a
D Lisak, A. Cygan, D Bermejo, J L. Domenech, Joseph T. Hodges, Ha Tran
The Hartmann-Tran profile (HTP), which has been recently recommended as a new standard in spectroscopic databases, is used to analyze spectra of several lines of H$_2$O diluted in N$_2$, SF$_6$, and in pure H$_2$O. This profile accounts for various
Vladimir L. Orkin, Eric L. Fleming, Christian George, Dwayne E. Heard, Charles H. Jackman, Michael J. Kurylo , Abdelwahid Mellouki , J B. Burkholder
The atmospheric loss processes of N2O and CH4, their estimated uncertainties, lifetimes, and impacts on ozone abundance and long-term trends are examined using atmospheric model calculations and updated kinetic and photochemical parameters and uncertainty
Joshua A. Gordon, Ryan D. Davis, Sara Lance, Margaret A. Tolbert
The development and characterization of a long working-distance optical trap to analyze a diverse range of particle phase transformations and crystal growth processes is described. Utilizing an upward propagating Gaussian beam and a down-ward propagating
This publication provides guidelines for conducting radiometric calibrations of electro-optical (EO) sensors. It is intended for use by managers, technical oversight personnel, scientists, and engineers as a reference for planning and successfully
Aaron N. Johnson, Joey T. Boyd, Eric Harman, Mohammad M. Khalil, Jacob E. Ricker, Christopher J. Crowley, Rodney A. Bryant, Iosif I. Shinder
The amount of CO 2 emitted from a coal-fired power plant (CFPP) is measured by continuous emissions monitoring systems (CEMS) permanently installed in the exhaust smokestack. Both the CO 2 concentration and the bulk flow are continuously measured by CEMS
David A. Long, Szymon S. Wojtewicz, Charles E. Miller, Joseph T. Hodges
We present new high accuracy measurements of the (30012)←(00001) CO¬2 band near 1575 nm recorded with a frequency-agile, rapid scanning cavity ring-down spectrometer. The resulting spectra were fit with the partially correlated, quadratic-speed-dependent
Vincent T. Sironneau, Hong Lin, Zachary Reed, Joseph T. Hodges
We present a cavity ring-down spectrometer which was developed for near-infrared measurements of laser absorption by atmospheric greenhouse gases. This system has several important attributes that make it possible to conduct broad spectral surveys and to
A natural gas burner has been used as a precise and accurate source for generating large quantities of carbon dioxide (CO2) to evaluate emissions measurements at near-industrial scale. Two methods for determining carbon dioxide emissions from stationary
The absorption spectrum of ethane was measured by frequency-stabilized cavity ring-down spectroscopy over the wave number range 5950-5967 cm-1. Spectra are reported for both pure ethane acquired at pressures near 3 Pa and ethane in air at pressures ranging
Lucy J. Carpenter, Stefan Reimann, Andreas Engel, Stephen Montzka, James B. Burkholder, Cathy Clerbaux, Bradley Hall, Shari A. Yvon-Lewis, Donald R. Blake, Marcel Dorf, Geoffre S. Dutton, Paul J. Fraser, Lucien Froidevaux, Fran?ois Hendrick, Jianxin Hu, Ashley Jones, Paul B. Krummel, Lambert J. Kuijpers, Michael J. Kurylo, Qing Liang, Emmanuel Mahieu, Jens M?hle, Simon O?Doherty, Keiichi Ohnishi, Vladimir L. Orkin, Klaus Pfeilsticker, Matt Rigby, Isobel J. Simpson, Yoko Yokouchi
Changes in the global atmospheric abundance of a substance are determined by the balance between its emissions and removal. Declines observed for ozone-depleting substances (ODSs) controlled under the Montreal Protocol are due to global emission reductions
We discuss developments at NIST towards improving the passive microwave brightness temperature standard. By reducing uncertainty we can provide a better calibration for improved congruency between future weather and climate monitoring radiometers. We
Thinh Q. Bui, David Long, Agata Cygan, Vincent T. Sironneau, Daniel Hogan, Priyanka M. Rapusinghe, Mitchio Okumura
Frequency-stabilized cavity ring-down spectroscopy (FS-CRDS) was used to study CO2 lineshapes in the (20013)←(00001) band centered near 2.06 um. Two rovibrational transitions were chosen for this study to measure non-Voigt collisional effects for air