Download or read book Measurement of Atmospheric Transmission Over Long Paths in the Infrared Spectral Region written by U. P. Oppenheim and published by . This book was released on 1984 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Instrumentation built for long path spectroradiometric measurement is described. Preliminary results for atmospheric transmission over a 7 km path are reported. A comparison is made with LOWTRAN computations. (Author).
Download or read book Infrared Atmospheric Transmission written by John N. Howard and published by . This book was released on 1961 with total page 134 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 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Influence of Atmospheric Transmission of Functions on Infrared Measurements in Planetary Atmospheres written by Irmhild Tannhäuser and published by . This book was released on 1967 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Atmospheric Transmission of Infrared Radiation from 2 5 Microns for Slant Paths from 35 000 Feet to the Upper Limit of the Atmosphere a Survey written by and published by . This book was released on 1967 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparison of Atmospheric Transmittance Measurements in the 0 4 0 7micro m 1 3 5 5micro m and 8 12micro m Spectral Regions with MODTRAN Considerations for Long Path Geometries Applicable for Theatre Defense written by and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report results from a contract tasking IARD Institute for Advanced Research and Development as follows: The contractor will investigate atmospheric transmission modelling techniques. During the research, the contractor will take observations by infrared sensors deployed during tropospheric operations to detect objects on the Earth's surface from a manned aircraft or from an unmanned airborne vehicle (UAV) using long, near-horizontal viewing geometries. The contractor will begin by repeating measurements collected during a previous EOARD contract under desert conditions with additional instruments that will enable us to test the predictions of MODTRAN code in the 0.4-0.7 micro-m (the photopic region), and in the 1.3-5.5 micro-m and 8-12 micro-m spectral regions. The measurements proposed would be performed in Israel in the winter, summer and autumn 2000 with an infrared spectroradiometer having both high signal-to-noise ratio and high spectral resolution. The wide range of absolute humidities and air temperatures will help in the validation of the MODTRAN code with special attention to the negative temperature dependence of the water continuum in the 8-12 micro-m spectral region. The spectroradiometer will be adapted to make the measurements in 1.3-3.0 micro-m spectral region without saturation of its detector. An additional spectroradiometer will measure the slant path visibility in the 0.4-0.7 micro-m photopic spectral region. The autumn measurements will be synchronized with slant path visibility measurements that will be done in the framework of MEIDEX experiment on NASA STS-107 (November 2000).
Download or read book Measurements of Trace Constituents from Atmospheric Infrared Emission and Absorption Spectra a Feasibility Study written by and published by . This book was released on 1974 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Review of Atmospheric Transmission Information in the Optical and Microwave Spectral Regions written by and published by . This book was released on 1976 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt: Much information has been generated over a long period of time on the transmission through the atmosphere of radiation of various wavelengths. This report represents an attempt to consolidate some of the available information into a single report. This report addresses five wavelengths each in the optical and microwave regions. Attenuation mechanisms considered are Rayleigh and Mie scattering and absorption by both water vapor and water drops. Atmospheres characterized by visibilities between 0.1 km (fog) and 325 km (clear air) and by rainfalls at rates up to 64 mm/hr are considered. Pertinent formulations and tables are provided to assist in calculating attenuation coefficients characteristic of a wide variety of atmospheres, and the adequacy of the data bases upon which such calculations rest is assessed. A limited amount of information is also provided on the attenuation characteristics of smoke and dust.
Download or read book Transmission of the Atmosphere in the Infra red a Review written by John Nelson Howard and published by . This book was released on 1962 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of High Resolution Infrared Laboratory Spectra of Atmospheric Interest 1981 written by Aaron Goldman and published by CRC Press. This book was released on 2017-11-22 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: The handbook presents spectra to be utilized for the detection and measurement of new constituents in the earth's atmosphere and to obtain data for common minor species with large gas amounts in the absorption cell (such as CH/sub 4/ and N/sub 2/O). These results can be applied in the identification of absorption features in atmospheric spectra determined over long atmospheric paths. The spectra were recorded with Fourier Transform Spectrometers which are more precise than grating spectrometers. Each molecule spectrum was plotted on two scales: a condensed scale covering the range from 75 to 300/cm in one frame, and an expanded view covering 20 or 10/cm per frame. Each plot contains the name of the molecule, chemical formula, the gas pressure, cell length, and estimated resolution of the spectrum.
Download or read book Infrared Continuum Absorption by Atmospheric Water Vapor in the 8 12 Micrometer Window written by and published by . This book was released on 1976 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have carried out a detailed analysis of several long-path-length transmission measurements in the 8 to 12 micrometer atmospheric window in order to determine the extinction coefficient due to the water vapor continuum. Our results indicate that three modifications to the current LOWTRAN atmospheric transmission model are required. The first two corrections are an improved fit to the pure water vapor continuum absorption coefficient and the elimination of the atmospheric broadened continuum term. Finally, and most critically, a strong measured temperature dependence must be included in the water vapor continuum absorption coefficient. For path lengths ranging from 10 to 50 km, failure to incorporate these corrections can lead to errors in the computed transmission ranging from factors of 2 to more than 10,000.
Download or read book Atmospheric Transmission and Weather Measurements written by Willard L. Derksen and published by . This book was released on 1953 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of the NML's participation in Operation TUMBLER-SNAPPER was to measure the transmissivity of the atmosphere and to obtain the temperature, humidity and other weather data which are pertinent in evaluating the results of experiments concerned with the effects of thermal radiation. The atmospheric attenuation of a ground level path indicated serious deviations because of atmospheric boil, dust and refraction effects. Measurement over a slant path, employing a hilltop station and approximating the path of thermal radiation from a nuclear detonation, gave reliable results. Lower transmissivities were found for ultraviolet and infrared wave lengths than for visible light and indicated the need for more complex attenuation relationships especially for spectral energy determinations. The NML transmissometer was operationally successful and was operated unattended in the area at the time of an atom bomb detonation. (Author).
Download or read book Atmospheric Transmission Measurements Using IR Lasers Fourier Transform Spectroscopy and Gas Filter Correlation Techniques written by J. Dowling and published by . This book was released on 1977 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: An extensive measurement system for atmospheric transmission field experiments is described with emphasis on the recent additions of a high resolution, scanning, Fourier interferometer system and a gas filter correlation spectrometer. Results obtained from three concurrent experiments used to generate a data base appropriate to high resolution transmission model validation are displayed. Laser extinction data, high resolution, long path atmospheric transmission spectra, and path integrated water vapor measurements are reported and discussed. Plans for future field experiments utilizing these three measurement techniques plus broadband infrared transmissometer and infrared target signature measurement are discussed.
Download or read book FTIR Measurements of Thermal Infrared Sky Radiance and Transmission written by and published by . This book was released on 1994 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Precise relative measurements of sky continuum and line emission and absorption have been made using FTIR spectroscopy. During conditions of horizontally uniform air composition, measurements of the variation of the spectral radiance with elevation angle sample an air column that varies simply as the cosecant of the elevation angle. In spectral regions that are optically thin, an extrapolation to zero air mass can be used to accurately determine instrumental background. An ambient temperature black body reference furnishes an accurate measurement of the instrumental spectral response. The excess sky emission above instrumental background relative to the local black body reference spectrum thus provides a calibrated sky radiance spectrum. This spectrum can be used to calculate the atmospheric transmission. As a test, transmission spectra have been directly obtained with the full moon as a backlighting source, and are in excellent agreement with the sky radiance derived transmission spectra. For spectral regions dominated by water, the continuum emission has been measured for paths involving the entire atmospheric column. Reasonable agreement with previous laboratory measurement of the continuum strength is obtained.
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 Comparison of Atmospheric Transmittance Measurements in the 3 5 Micrometers and 8 12 Micrometers Spectral Regions With MODTRAN Consideration for Long Path Geometries written by and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radiance measurements conducted during tropospheric operations to detect objects on the Earth's surface from a manned aircraft or from an unmanned airborne vehicle (UAV) will involve long, near-horizontal viewing geometries. The computer code MODTRAN is widely used for the prediction of the propagation of infrared radiation through the lower atmosphere. This program was undertaken by the IARD to test and validate the predictions of the MODTRAN code for the 3-5 micrometer and 8-l2 micrometer spectral regions under semi-arid desert conditions with well defined meteorological parameters.
Download or read book Infrared Radiation in a Real Tropical Atmosphere written by Lee A. Young and published by . This book was released on 1977 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transmission of infrared radiation in the 8-13 and 16.5-21 micrometers spectral regions from 3 km altitude through the atmosphere to outer space has been evaluated. Analysis of tropical radiosonde atmospheric profiles of temperature and humidity shows that fluctuations in the total amount of water vapor above 3 km cause the transmission to vary by amounts from 10% to two orders of magnitude. Fluctuations in the effective temperature or pressure for absorption are shown to be small. The Curtis-Godson approximation is analyzed in detail for this problem. Also, effective parameters describing an atmospheric slant path are formulated for absorption by the water vapor continuum. The total amount of water vapor above 3 km varies chiefly as the trade wind inversion rises above or falls below that altitude; it correlates poorly with the absolute humidity at 3 km. The atmospheric transmission can be obtained in real time from measurements of atmospheric emission. Fluctuations in the effective emission temperature, calculated from radiosonde data, are relatively small. However, further study of the effect of cirrus clouds on the transmission-emission relationship would be desirable. (Author).
