Download or read book First Trace Gas Measurements Using Fourier Transform Infrared Solar Absorption Spectroscopy at the University of Toronto Atmospheric Observatory written by Aldona Wiacek and published by . This book was released on 2006 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt: A systematic study showed that the effect of several different layering schemes (implicit retrieval constraints) on the retrieved vertical profile is less than 5% for N2O and HF, and less than 2% for NO, NO 2, CH4 and HCl; however, retrieved profiles of H2O showed differences up to 13% when the layering scheme was varied. A maximum tropospheric layer thickness of 0.8 km is inferred for accurate H2O retrievals. A new high-resolution (0.004 cm-1) research-grade Fourier transform spectrometer was installed at the University of Toronto Atmospheric Observatory (TAO), and commissioned in October 2001. TAO fills a coverage gap in North America in the Network for the Detection of Atmospheric Composition Change (NDACC), and was accepted as a Complementary Station in March 2004 as a direct result of work presented in this thesis. Finally, the usefulness of Fourier Transform InfraRed (FTIR) observations for studying different regions of the atmosphere was demonstrated by (1) documenting a limited sensitivity of ground-based measurements to mesospheric-lower thermospheric concentrations of NO, (2) correlating anomalously high stratospheric HCl, HF and O3 concentrations derived at TAO with the passage of a polar air filament above Toronto, and (3) showing very good agreement between monthly mean abundances of tropospheric CO between January 2002--September 2003 and spatially coincident MOPITT satellite measurements. Trace gas concentrations are derived using an existing Optimal Estimation Method (OEM) retrieval algorithm implemented at TAO as part of this work. A set of prior constraints necessary for retrievals of vertical profiles of trace gases using the OEM approach was optimized, and includes a priori volume mixing ratio profiles suited to TAO's location, and the prior and measurement noise covariances. A three-year time series of O3, NO. NO2, HCl, HF, N2O and CH4 (exhibiting the known seasonal cycles) was submitted to the NDACC database for long-terra monitoring, trend detection, and satellite validation purposes. A quantitative retrieval characterization was performed whereby the averaging kernels, weighting functions, measurement, smoothing and temperature error covariances of the retrievals of these seven gases were calculated. The degrees of freedom for signal ranged from 1.10 for NO2 to 4.12 for N2O.

Download or read book Handbook of Humidity Measurement Volume 1 written by Ghenadii Korotcenkov and published by CRC Press. This book was released on 2018-03-15 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first volume of The Handbook of Humidity Measurement focuses on the review of devices based on optical principles of measurement such as optical UV, fluorescence hygrometers, optical and fiber-optic sensors of various types. Numerous methods for monitoring the atmosphere have been developed in recent years, based on measuring the absorption of electromagnetic field in different spectral ranges. These methods, covering the optical (FTIR and Lidar techniques), as well as a microwave and THz ranges are discussed in detail in this volume. The role of humidity-sensitive materials in optical and fiber-optic sensors is also detailed. This volume describes the reasons for controlling the humidity, features of water and water vapors, and units used for humidity measurement.

Download or read book Assessment of Trace Gas Observations from the Toronto Atmospheric Observatory written by Jeffrey Ryan Taylor and published by . This book was released on 2008 with total page 542 pages. Available in PDF, EPUB and Kindle. Book excerpt: A high-resolution infrared Fourier Transform Spectrometer (FTS) has been operational at the Toronto Atmospheric Observatory (TAO) since May 2002. An optimal estimation retrieval technique is used to analyse the observed spectra and provide regular total and partial column measurements of trace gases in the troposphere and stratosphere as part of the Network for the Detection of Atmospheric Composition Change. The quality of these results were assessed through two ground-based validation campaigns, comparisons with three satellite instruments, and comparison with a three-dimensional chemical transport model.The two ground-based campaigns involved two lower-resolution FTS instruments: the University of Toronto FTS and the Portable Atmospheric Research Interferometric Spectrometer for the Infrared. The first campaign took place over the course of four months and is the longest side-by-side intercomparison of ground-based FTS instruments, to date. The second campaign was more focused and involved all three instruments measuring over a two-week period. Simultaneous measurements of O3, HCl, N2O, and CH4 were recorded and average total column differences were all

Download or read book Measurements and Data Analysis from a Balloon borne Fourier Transform Spectrometer written by Debra Wunch and published by . This book was released on 2007 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2007 with total page 924 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Precision Measurement of Atmospheric Trace Gases Using Fourier Transform Infrared Spectroscopy written by Michael Brian Esler and published by . This book was released on 1997 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1995 with total page 962 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book On line Measurement of the Infrared Spectra of Gas Chromatographic Eluents written by Peter R. Griffiths and published by . This book was released on 1976 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technical Support for the Measurements of Atmospheric Gas Constituents Final Report written by and published by . This book was released on 1996 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Quantitative gas analysis using Fourier transform infrared spectroscopy written by and published by . This book was released on 1979 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Atmospheric Measurements of Trace Pollutants written by and published by . This book was released on 1982 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Quantitative Detection of Trace Gas Species in the Atmosphere Using LED Broadband Cavity Enhanced Absorption Spectroscopy written by Anna Marie Hollingsworth and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A broadband version of cavity enhanced absorption spectroscopy (BBCEAS) has been applied to measure the ambient concentrations of reactive trace gases, particularly nitrogen dioxide (NO2) in the polluted urban environment and molecular iodine (I2) in the marine boundary layer. The spectrometer's light source, a light emitting diode (LED), enables absorption spectra of gas samples to be acquired over 50 nm bandwidths at visible and nearultraviolet wavelengths. Differential optical absorption spectroscopy (DOAS) is then applied to unambiguously identify and quantify the various absorbers present in the samples. Especially difficult operating conditions were encountered during the instrument's first field deployment onboard the research vessel RRS Discovery. As a result, the instrument did not achieve the I2 detection limits it had demonstrated in laboratory testing and was unable to detect any I2 signal in the mid-Atlantic Ocean during the Reactive Halogens in the Marine Boundary Layer Experiment. However, iodine was detected around many night-time low tides during the BIOFLUX II campaign at the Mace Head Atmospheric Research Station in County Galway, Ireland. The maximum I2 concentration of 608 pptv (parts per trillion by volume) correlated with the campaign's lowest tide, and is three times greater than any previous report of atmospheric I2 concentrations. The BIOFLUX observations support current understanding that coastal I2 derives from seaweed (particularly kelp species) exposed to air around low tide. LED-BBCEAS measurements of NO2 made on the University campus during the Leicester Air Quality Measurement Project are compared with data from two chemiluminescence instruments. The need to closely co-locate instruments during comparisons of the various techniques is discussed, and evidence of a possible interference in the chemiluminescence measurements has been found.

Download or read book Analysis of Natural Gas by Fourier Transform Infrared Spectroscopy written by and published by . This book was released on 1996 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: A fast experimental protocol was established for the simultaneous determination of methane, ethane, propane, and butane in nitrogen from Fourier transform infrared (FT-IR) spectra. The method is based on correlations established between known gas compositions and their FT-IR spectra. The spectra were collected in the region of 4,000 to 400/cm through KBr windows in a 100-mm pathlength gas sample cell operating at 100, 300, 500, 700, and 1,000 mm Hg pressure. Correlation between blending partial pressure or GC-based analysis and FT-IR data produced squared correlation coefficients (R2) in excess of 0.98. Total required analytical time is less than 2 minutes. jg p3.

Download or read book Fourier Transform Infrared Spectrometry written by Peter R. Griffiths and published by John Wiley & Sons. This book was released on 2007-03-16 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt: A bestselling classic reference, now expanded and updated to cover the latest instrumentation, methods, and applications The Second Edition of Fourier Transform Infrared Spectrometry brings this core reference up to date on the uses of FT-IR spectrometers today. The book starts with an in-depth description of the theory and current instrumentation of FT-IR spectrometry, with full chapters devoted to signal-to-noise ratio and photometric accuracy. Many diverse types of sampling techniques and data processing routines, most of which can be performed on even the less expensive instruments, are then described. Extensively updated, the Second Edition: * Discusses improvements in optical components * Features a full chapter on FT Raman Spectrometry * Contains new chapters that focus on different ways of measuring spectra by FT-IR spectrometry, including fourteen chapters on such techniques as microspectroscopy, internal and external reflection, and emission and photoacoustic spectrometry * Includes a new chapter introducing the theory of vibrational spectrometry * Organizes material according to sampling techniques Designed to help practitioners using FT-IR capitalize on the plethora of techniques for modern FT-IR spectrometry and plan their experimental procedures correctly, this is a practical, hands-on reference for chemists and analysts. It's also a great resource for students who need to understand the theory, instrumentation, and applications of FT-IR.

Download or read book Collaborative Study of Analysis of High Resolution Infrared Atmospheric Spectra Between NASA Langley Research Center and the University of Denver written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-25 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Langley-D.U. collaboration on the analysis of high resolution infrared atmospheric spectra covered a number of important studies of trace gases identification and quantification from field spectra, and spectral line parameters analysis. The collaborative work included: Quantification and monitoring of trace gases from ground-based spectra available from various locations and seasons and from balloon flights. Studies toward identification and quantification of isotopic species, mostly oxygen and Sulfur isotopes. Search for new species on the available spectra. Update of spectroscopic line parameters, by combining laboratory and atmospheric spectra with theoretical spectroscopy methods. Study of trends of atmosphere trace constituents. Algorithms developments, retrievals intercomparisons and automatization of the analysis of NDSC spectra, for both column amounts and vertical profiles. Goldman, Aaron Langley Research Center

Download or read book Measurement of Climate relevant Trace Gases Via Infrared Spectroscopy written by Marc Christoph Geibel and published by . This book was released on 2011 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Quantifying Trace Atmospheric Gases Using Open Path FTIR Measurements Combined with a Nonlinear Least Squares Fitting Algorithm written by Thomas C. Connor and published by . This book was released on 2004 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt: