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Robert R. Gamache

Bio: Robert R. Gamache is an academic researcher from University of Massachusetts Lowell. The author has contributed to research in topics: HITRAN & Spectral line. The author has an hindex of 50, co-authored 159 publications receiving 21655 citations. Previous affiliations of Robert R. Gamache include Dartmouth College & National Research Council.


Papers
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Journal ArticleDOI
TL;DR: The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity, and molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth.
Abstract: This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is composed of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity. Moreover, molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth. Of considerable note, experimental IR cross-sections for almost 300 additional molecules important in different areas of atmospheric science have been added to the database. The compilation can be accessed through www.hitran.org. Most of the HITRAN data have now been cast into an underlying relational database structure that offers many advantages over the long-standing sequential text-based structure. The new structure empowers the user in many ways. It enables the incorporation of an extended set of fundamental parameters per transition, sophisticated line-shape formalisms, easy user-defined output formats, and very convenient searching, filtering, and plotting of data. A powerful application programming interface making use of structured query language (SQL) features for higher-level applications of HITRAN is also provided.

7,638 citations

Journal ArticleDOI
TL;DR: The data and features that have been added or replaced since the previous edition of HITRAN are described, including instances of critical data that are forthcoming.
Abstract: Since its first publication in 1973, the HITRAN molecular spectroscopic database has been recognized as the international standard for providing the necessary fundamental spectroscopic parameters for diverse atmospheric and laboratory transmission and radiance calculations. There have been periodic editions of HITRAN over the past decades as the database has been expanded and improved with respect to the molecular species and spectral range covered, the number of parameters included, and the accuracy of this information. The 1996 edition not only includes the customary line-by-line transition parameters familiar to HITRAN users, but also cross-section data, aerosol indices of refraction, software to filter and manipulate the data, and documentation. This paper describes the data and features that have been added or replaced since the previous edition of HITRAN. We also cite instances of critical data that are forthcoming.

1,846 citations

Journal ArticleDOI
TL;DR: In this paper, a new molecular spectroscopic database for high-temperature modeling of the spectra of molecules in the gas phase is described, called HITEMP, which is analogous to the HITRAN database but encompasses many more bands and transitions than HitRAN for the absorbers H2O, CO2, CO, NO and OH.
Abstract: A new molecular spectroscopic database for high-temperature modeling of the spectra of molecules in the gas phase is described. This database, called HITEMP, is analogous to the HITRAN database but encompasses many more bands and transitions than HITRAN for the absorbers H2O, CO2, CO, NO, and OH. HITEMP provides users with a powerful tool for a great many applications: astrophysics, planetary and stellar atmospheres, industrial processes, surveillance, non-local thermodynamic equilibrium problems, and investigating molecular interactions, to name a few. The sources and implementation of the spectroscopic parameters incorporated into HITEMP are discussed.

1,715 citations

Journal ArticleDOI
TL;DR: The HITRAN molecular absorption database as mentioned in this paper contains line parameters for 31 species and their isotopomers that are significant for terrestrial atmospheric studies, including chlorofluorocarbons and other molecular species that are not amenable to line-by-line representation.
Abstract: We describe in this paper the modifications, improvements, and enhancements to the HITRAN molecular absorption database that have occurred in the two editions of 1991 and 1992 The current database includes line parameters for 31 species and their isotopomers that are significant for terrestrial atmospheric studies This line-by-line portion of HITRAN presently contains about 709,000 transitions between 0 and 23,000/cm and contains three molecules not present in earlier versions: COF2, SF6, and H2S The HITRAN compilation has substantially more information on chlorofluorocarbons and other molecular species that exhibit dense spectra which are not amenable to line-by-line representation The user access of the database has been advanced, and new media forms are now available for use on personal computers

1,442 citations

Journal ArticleDOI
TL;DR: The HITRAN compilation consists of several components useful for radiative transfer calculation codes: high-resolution spectroscopic parameters of molecules in the gas phase, absorption cross-sections for molecules with very dense spectral features, aerosol refractive indices, ultraviolet line-by-line parameters and absorptionCross-sections, and associated database management software.
Abstract: This paper describes the status circa 2001, of the HITRAN compilation that comprises the public edition available through 2001. The HITRAN compilation consists of several components useful for radiative transfer calculation codes: high-resolution spectroscopic parameters of molecules in the gas phase, absorption cross-sections for molecules with very dense spectral features, aerosol refractive indices, ultraviolet line-by-line parameters and absorption cross-sections, and associated database management software. The line-by-line portion of the database contains spectroscopic parameters for 38 molecules and their isotopologues and isotopomers suitable for calculating atmospheric transmission and radiance properties. Many more molecular species are presented in the infrared cross-section data than in the previous edition, especially the chlorofluorocarbons and their replacement gases. There is now sufficient representation so that quasi-quantitative simulations can be obtained with the standard radiance codes. In addition to the description and justification of new or modified data that have been incorporated since the last edition of HITRAN (1996), future modifications are indicated for cases considered to have a significant impact on remote-sensing experiments. (C) 2003 Elsevier Ltd. All rights reserved.

1,231 citations


Cited by
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Journal ArticleDOI
01 Apr 1988-Nature
TL;DR: In this paper, a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) is presented.
Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

9,929 citations

Journal ArticleDOI
TL;DR: The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity, and molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth.
Abstract: This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is composed of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity. Moreover, molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth. Of considerable note, experimental IR cross-sections for almost 300 additional molecules important in different areas of atmospheric science have been added to the database. The compilation can be accessed through www.hitran.org. Most of the HITRAN data have now been cast into an underlying relational database structure that offers many advantages over the long-standing sequential text-based structure. The new structure empowers the user in many ways. It enables the incorporation of an extended set of fundamental parameters per transition, sophisticated line-shape formalisms, easy user-defined output formats, and very convenient searching, filtering, and plotting of data. A powerful application programming interface making use of structured query language (SQL) features for higher-level applications of HITRAN is also provided.

7,638 citations

Journal ArticleDOI
TL;DR: A rapid and accurate radiative transfer model (RRTM) for climate applications has been developed and the results extensively evaluated as discussed by the authors, which is performed using the correlated-k method: the k distributions are attained directly from the LBLRTM line-byline model, which connects the absorption coefficients used by RRTM to high-resolution radiance validations done with observations.
Abstract: A rapid and accurate radiative transfer model (RRTM) for climate applications has been developed and the results extensively evaluated. The current version of RRTM calculates fluxes and cooling rates for the longwave spectral region (10–3000 cm−1) for an arbitrary clear atmosphere. The molecular species treated in the model are water vapor, carbon dioxide, ozone, methane, nitrous oxide, and the common halocarbons. The radiative transfer in RRTM is performed using the correlated-k method: the k distributions are attained directly from the LBLRTM line-by-line model, which connects the absorption coefficients used by RRTM to high-resolution radiance validations done with observations. Refined methods have been developed for treating bands containing gases with overlapping absorption, for the determination of values of the Planck function appropriate for use in the correlated-k approach, and for the inclusion of minor absorbing species in a band. The flux and cooling rate results of RRTM are linked to measurement through the use of LBLRTM, which has been substantially validated with observations. Validations of RRTM using LBLRTM have been performed for the midlatitude summer, tropical, midlatitude winter, subarctic winter, and four atmospheres from the Spectral Radiance Experiment campaign. On the basis of these validations the longwave accuracy of RRTM for any atmosphere is as follows: 0.6 W m−2 (relative to LBLRTM) for net flux in each band at all altitudes, with a total (10–3000 cm−1) error of less than 1.0 W m−2 at any altitude; 0.07 K d−1 for total cooling rate error in the troposphere and lower stratosphere, and 0.75 K d−1 in the upper stratosphere and above. Other comparisons have been performed on RRTM using LBLRTM to gauge its sensitivity to changes in the abundance of specific species, including the halocarbons and carbon dioxide. The radiative forcing due to doubling the concentration of carbon dioxide is attained with an accuracy of 0.24 W m−2, an error of less than 5%. The speed of execution of RRTM compares favorably with that of other rapid radiation models, indicating that the model is suitable for use in general circulation models.

6,861 citations

Journal ArticleDOI
TL;DR: The 6S code has still limitations; it cannot handle spherical atmosphere and as a result, it cannot be used for limb observations, and the decoupling the authors are using for absorption and scattering effects does not allow to use the code in presence of strong absorption bands.
Abstract: Remote sensing from satellite or airborne platforms of land or sea surfaces in the visible and near infrared is strongly affected by the presence of the atmosphere along the path from Sun to target (surface) to sensor. This paper presents 6S (Second Simulation of the Satellite Signal in the Solar Spectrum), a computer code which can accurately simulate the above problems. The 6S code is an improved version of 5S (Simulation of the Satellite Signal in the Solar Spectrum), developed by the Laboratoire d'Optique Atmospherique ten years ago. The new version now permits calculations of near-nadir (down-looking) aircraft observations, accounting for target elevation, non lambertian surface conditions, and new absorbing species (CH/sub 4/, N/sub 2/O, CO). The computational accuracy for Rayleigh and aerosol scattering effects has been improved by the use of state-of-the-art approximations and implementation of the successive order of scattering (SOS) algorithm. The step size (resolution) used for spectral integration has been improved to 2.5 nm. The goal of this paper is not to provide a complete description of the methods used as that information is detailed in the 6S manual, but rather to illustrate the impact of the improvements between 5S and 6S by examining some typical remote sensing situations. Nevertheless, the 6S code has still limitations. It cannot handle spherical atmosphere and as a result, it cannot be used for limb observations. In addition, the decoupling the authors are using for absorption and scattering effects does not allow to use the code in presence of strong absorption bands.

2,955 citations