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51. Use of arm measurements to improve radiative transfer models used in climate models

Author

Bergstrom, Robert W, Kinne, S, Toon, O. B, Westphal, Doug, Clough, Tony, and Mlawer, Eli

Subjects
Meteorology And Climatology
Abstract

The demands of accurate predictions of radiative transfer for climate applications are well-documented. While much effort is being devoted to evaluating the accuracy of the GCM radiative transfer schemes, the problem of developing accurate, computationally efficient schemes for climate models still remains. This paper discusses our efforts in developing accurate and fast computational methods for global and regional climate models.

Published
1995

54. Use of SAPHIR and GMI for intercalibration of polar orbiting passive microwave water vapor sounders

Author

Payne, Vivienne, Wilheit, Thomas, Wang, James, Jones, W., Datta, S., Santos-Garcia, Adrea, Brogniez, Hélène, Clain, Gaëlle, Luo, M., Moncet, Jean-Luc, Mlawer, Eli, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Texas A&M University [College Station], Science Systems and Applications, Inc. [Lanham] (SSAI), University of Central Florida [Orlando] (UCF), SPACE - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Atmospheric and Environmental Research, Inc. (AER), and Cardon, Catherine

Subjects
[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [PHYS.PHYS.PHYS-AO-PH] Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2014

55. Determination of Near-IR Water Vapor Self Continuum from Observations

Author

Mlawer, Eli, Gombos, Daniel, Alvarado, Matthew, Cady-Pereira, Karen, Payne, Vivienne, Chase, Alison, and Michalsky, Joseph

Subjects
Remote Sensing and Radiative Transfer
Abstract

There is still significant uncertainty in the strength of water vapor continuum absorption in the windows between near-infrared water vapor bands. Many radiation codes obtain their water vapor continuum absorption coefficients from the MT CKD continuum model, which derives its near-infrared values from a water vapor line-shape function that has been constrained by continuum measurements in other spectral regions. A number of recent laboratory studies have shown that the strength of the near-IR self continuum in the MT CKD model is too low, but these laboratory studies disagree with each other by more than an order of magnitude. At the high end of the range of measured strengths, the self continuum absorbs a significant amount of solar radiation, so it is crucial that other observational studies are performed to establish the actual strength of this absorption source. We describe here an analysis of measurements from a solar FTS in Lamont, OK, part of the Total Carbon Column Observing Network (TCCON). Thirteen periods on individual days in 2012 were identified as being reasonably stable with respect to aerosol optical depth and precipitable water vapor. For each period, the FTS measurements, coincident measurements from a Normal Incidence Multi-Filter Radiometer (NIMFR) at the DOE ARM site, and calculations from the Line-By-Line Radiative Transfer Model (LBLRTM) were used to obtain aerosol optical depths in window regions from 8000-20000 cm−1, which were then extended to lower wavenumbers through a generalized Angstrom relationship. In windows between 4000-7000 cm−1, these aerosol optical depths, and the LBLRTM optical depths without any self continuum, were subtracted from FTS-derived total optical depths. The self continuum absorption coefficients that were derived from this procedure were at the low end of the recent laboratory studies, but higher than the current version of MT CKD. The implications of the results of this study with respect to the absorption of solar irradiance will be discussed. &nbsp

Published
2014
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56. MULTISPECTRUM ANALYSIS OF THE OXYGEN A-BAND

Author

Drouin, Brian, primary, Wishnow, Edward, additional, Robichaud, David, additional, Mlawer, Eli, additional, Hodges, Joseph, additional, Devi, V., additional, Benner, D., additional, Yu, Shanshan, additional, Sung, Keeyoon, additional, Payne, Vivienne, additional, Oyafuso, Fabiano, additional, Guillaume, Alexander, additional, Crawford, Timothy, additional, Cich, Matthew, additional, and Brown, Linda, additional

Published
2016
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60. Improvement of the Simulation of Cloud Longwave Scattering in Broadband Radiative Transfer Models.

Author

GUANGLIN TANG, PING YANG, KATTAWAR, GEORGE W., XIANGLEI HUANG, MLAWER, ELI J., BAUM, BRYAN A., and KING, MICHAEL D.

Subjects
GENERAL circulation model, CLOUDS, ENERGY budget (Geophysics), RADIATIVE transfer, DISCRETE ordinates method in transport theory
Abstract

Cloud longwave scattering is generally neglected in general circulation models (GCMs), but it plays a significant and highly uncertain role in the atmospheric energy budget as demonstrated in recent studies. To reduce the errors caused by neglecting cloud longwave scattering, two new radiance adjustment methods are developed that retain the computational efficiency of broadband radiative transfer simulations. In particular, two existing scaling methods and the two new adjustment methods are implemented in the Rapid Radiative Transfer Model (RRTM). The results are then compared with those based on the Discrete Ordinate Radiative Transfer model (DISORT) that explicitly accounts for multiple scattering by clouds. The two scaling methods are shown to improve the accuracy of radiative transfer simulations for optically thin clouds but not effectively for optically thick clouds. However, the adjustment methods reduce computational errors over a wide range, from optically thin to thick clouds. With the adjustment methods, the errors resulting from neglecting cloud longwave scattering are reduced to less than 2W-22 for the upward irradiance at the top of the atmosphere and less than 0.5W-22 for the surface downward irradiance. The adjustment schemes prove to be more accurate and efficient than a four-stream approximation that explicitly accounts for multiple scattering. The neglect of cloud longwave scattering results in an underestimate of the surface downward irradiance (cooling effect), but the errors are almost eliminated by the adjustment methods (warming effect). [ABSTRACT FROM AUTHOR]

Published
2018
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62. Ozone depletion by hydrofluorocarbons

Author

Hurwitz, Margaret M., primary, Fleming, Eric L., additional, Newman, Paul A., additional, Li, Feng, additional, Mlawer, Eli, additional, Cady-Pereira, Karen, additional, and Bailey, Roshelle, additional

Published
2015
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63. RRTMGP: A High-Performance Broadband Radiation Code for the Next Decade

Author

ATMOSPHERIC AND ENVIRONMENTAL RESEARCH INC LEXINGTON MA, Mlawer, Eli, ATMOSPHERIC AND ENVIRONMENTAL RESEARCH INC LEXINGTON MA, and Mlawer, Eli

Abstract

The radiation calculations needed for climate simulations require many independent and complicated calculations, and are therefore an inviting target for new computing architectures such as Many- Integrated-Cores (MICs) and Graphical Processing Units (GPUs). We are developing RRTMGP ( P stands for parallel ), a modern version of the radiation code (RRTMG) used by many climate models, directed at the current generation of vector- and cache-based computational architectures. This code will retain the high accuracy of RRTMG, but is being developed from scratch to make it more flexible and amenable to optimization across a wide range of platforms. The objective is a single wellmaintained, well-documented, and efficient radiation code that can be used by the modeling community for a diverse range of applications across a wide range of computing facilities. RRTMGP will exhibit profound improvements in speed for GPU and vector CPU machines and lesser, but still valuable, speed-ups on other CPU-based platforms relative to the current version of the code.

Published
2014

65. The Continual Intercomparison of Radiation Codes: Results from Phase I

Author

Oreopoulos, Lazaros, primary, Mlawer, Eli, additional, Delamere, Jennifer, additional, Shippert, Timothy, additional, Cole, Jason, additional, Fomin, Boris, additional, Iacono, Michael, additional, Jin, Zhonghai, additional, Li, Jiangnan, additional, Manners, James, additional, Räisänen, Petri, additional, Rose, Fred, additional, Zhang, Yuanchong, additional, Wilson, Michael J., additional, and Rossow, William B., additional

Published
2012
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68. Evaluation of radiation scheme performance within chemistry climate models

Author

Forster, Piers M., primary, Fomichev, Victor I., additional, Rozanov, Eugene, additional, Cagnazzo, Chiara, additional, Jonsson, Andreas I., additional, Langematz, Ulrike, additional, Fomin, Boris, additional, Iacono, Michael J., additional, Mayer, Bernhard, additional, Mlawer, Eli, additional, Myhre, Gunnar, additional, Portmann, Robert W., additional, Akiyoshi, Hideharu, additional, Falaleeva, Victoria, additional, Gillett, Nathan, additional, Karpechko, Alexey, additional, Li, Jiangnan, additional, Lemennais, Perrine, additional, Morgenstern, Olaf, additional, Oberländer, Sophie, additional, Sigmond, Michael, additional, and Shibata, Kiyotaka, additional

Published
2011
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78. The Continual Intercomparison of Radiation Codes (CIRC): A New Standard for Evaluating GCM Radiation Codes.

Author

Oreopoulos, Lazaros, Mlawer, Eli, Delamere, Jennifer, and Shippert, Timothy

Subjects
*ATMOSPHERIC radiation, *RADIATION chemistry, *RADIATIVE transfer, *ELECTROMAGNETIC measurements, *ELECTROMAGNETIC waves, *HEAT radiation & absorption
Abstract

The Continual Intercomparison of Radiation Codes (CIRC) is intended as an evolving and regularly updated permanent reference source for GCM-type radiative transfer (RT) code evaluation that will help in the improvement of radiation parameterizations. CIRC seeks to establish itself as the standard against which code performance is documented in scientific publications and coordinated joint modeling activities such as GCM intercomparisons. A feature that distinguishes CIRC from previous intercomparisons is that its pool of cases is largely based on observations. Atmospheric and surface input, as well as radiative fluxes used for consistency checks with the reference line-by-line calculations come primarily from the Atmospheric Radiation Measurement (ARM) Climate Research Facility measurements and satellite observations compiled in the Broadband Heating Rate Profile (BBHRP) product. Additional datasets beyond BBHRP such as measurements from ARM field campaigns and spectral radiances from the AERI instrument are also used to complete the set of desired cases and to ensure the quality of the input. For Phase I, launched in June, CIRC aims to assess the baseline errors of GCM RT codes and therefore provides test cases that evaluate performance under the least challenging conditions, i.e, well-understood clear-sky and homogeneous, single-layer overcast liquid cloud cases. [ABSTRACT FROM AUTHOR]

Published
2009
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79. Atmospheric longwave irradiance uncertainty: Pyrgeometers compared to an absolute sky-scanning radiometer, atmospheric emitted radiance interferometer, and radiative transfer model calculations

Author

Philipona, Rolf, primary, Dutton, Ellsworth G., additional, Stoffel, Tom, additional, Michalsky, Joe, additional, Reda, Ibrahim, additional, Stifter, Armin, additional, Wendung, Peter, additional, Wood, Norm, additional, Clough, Shepard A., additional, Mlawer, Eli J., additional, Anderson, Gail, additional, Revercomb, Henry E., additional, and Shippert, Timothy R., additional

Published
2001
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84. Reviewing atmospheric radiative transfer modeling: new developments in high- and moderate-resolution FASCODE/FASE and MODTRAN

Author

Anderson, Gail P., primary, Kneizys, F. X., additional, Chetwynd, Jr., James H., additional, Rothman, Laurence S., additional, Hoke, Michael L., additional, Berk, Alexander, additional, Bernstein, Lawrence S., additional, Acharya, Prabhat K., additional, Snell, Hilary E., additional, Mlawer, Eli, additional, Clough, Shepard A., additional, Wang, Jinxue, additional, Lee, Szu-Chia, additional, Revercomb, Henry E., additional, Yokota, Tatsuya, additional, Kimball, L. M., additional, Shettle, Eric P., additional, Abreu, Leonard W., additional, and Selby, John E. A., additional

Published
1996
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87. Reviewing atmospheric radiative transfer modeling: new developments in high- and moderate-resolution FASCODE/FASE and MODTRAN.

Author

Anderson, Gail P., Kneizys, F. X., Chetwynd Jr., James H., Rothman, Laurence S., Hoke, Michael L., Berk, Alexander, Bernstein, Lawrence S., Acharya, Prabhat K., Snell, Hilary E., Mlawer, Eli, Clough, Shepard A., Wang, Jinxue, Lee, Szu-Chia, Revercomb, Henry E., Yokota, Tatsuya, Kimball, L. M., Shettle, Eric P., Abreu, Leonard W., and Selby, John E. A.

Published
1996
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90. The HITRAN2020 molecular spectroscopic database

Author

Gordon, Iouli, Rothman, Laurence S, Hargreaves, Robert, Hashemi, Robab, Karlovets, Ekaterina, Skinner, Frances, Conway, Eamon, Hill, Christian, Kochanov, Roman, Tan, Yan, Wcislo, Piotr, Finenko, Artem, Nelson, Kyle, Bernath, Peter, Birk, Manfred, Boudon, Vincent, Campargue, Alain, Chance, Kelly, Coustenis, Athena, Drouin, Brian, Flaud, Jean-Marie, Gamache, Robert R, Hodges, Joseph, Jacquemart, David, Mlawer, Eli, Nikitin, Andrey, Perevalov, Valery, Rotger, Maud, Tennyson, Jonathan, Toon, Geoofrey, Tran, Ha, Tyuterev, Vladimir, Adkins, Erin, Baker, Ashley, Barbe, Alain, Can��, Elisabetta, Cs��sz��r, Attila, Egorov, Oleg, Fleisher, Adam, Fleurbaey, Helene, Foltynowicz, Aleksandra, Furtenbacher, Tibor, Harrison, Jeremy, Hartmann, Jean-Michel, Horneman, Veli-Matti, Huang, Xinchuan, Karman, Tijs, Karns, Joshua, Kassi, Samir, Kleiner, Isabelle, Kofman, Vincent, Kwabia, Fridolin, Lee, Timothy, Long, David, Lukashevskaya, Anastasia, Schwenke, David, Lyulin, Oleg, Makhnev, Vladimir, Matt, Wyatt, Massie, Steven, Melosso, Mattia, Mikhailenko, Semen, Mondelain, Didier, Muller, Holger, Naumenko, Olga, Perrin, Agnes, Polyansky, Oleg, Raddaoui, emna, Raston, Paul, Reed, Zachary, Rey, Michael, Richard, Cyril, Tobias, Roland, Sadiek, Ibrahim, Starikova, Evgenia, Sung, Keeyoon, Tamassia, Filippo, Tashkun, Sergey, Auwera, Jean Vander, Vasilenko, Irina, Vigasin, Andrey, Villanueva, Geronimo, Vispoel, Bastien, Wagner, Georg, Yachmenev, Andrey, and Yurchenko, Sergey

Subjects
3. Good health
Abstract

Journal of quantitative spectroscopy & radiative transfer 277, 107949 (2021). doi:10.1016/j.jqsrt.2021.107949, The HITRAN database is a compilation of molecular spectroscopic parameters. It was established in the early 1970s and is used by various computer codes to predict and simulate the transmission and emission of light in gaseous media (with an emphasis on terrestrial and planetary atmospheres). The HITRAN compilation is composed of five major components: the line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, experimental infrared absorption cross-sections (for molecules where it is not yet feasible for representation in a line-by-line form), collision-induced absorption data, aerosol indices of refraction, and general tables (including partition sums) that apply globally to the data. This paper describes the contents of the 2020 quadrennial edition of HITRAN. The HITRAN2020 edition takes advantage of recent experimental and theoretical data that were meticulously validated, in particular, against laboratory and atmospheric spectra. The new edition replaces the previous HITRAN edition of 2016 (including its updates during the intervening years).All five components of HITRAN have undergone major updates. In particular, the extent of the updates in the HITRAN2020 edition range from updating a few lines of specific molecules to complete replacements of the lists, and also the introduction of additional isotopologues and new (to HITRAN) molecules: SO, CH$_3$F, GeH$_4$, CS$_2$, CH$_3$I and NF. Many new vibrational bands were added, extending the spectral coverage and completeness of the line lists. Also, the accuracy of the parameters for major atmospheric absorbers has been increased substantially, often featuring sub-percent uncertainties. Broadening parameters associated with the ambient pressure of water vapor were introduced to HITRAN for the first time and are now available for several molecules.The HITRAN2020 edition continues to take advantage of the relational structure and efficient interface available at www.hitran.org and the HITRAN Application Programming Interface (HAPI). The functionality of both tools has been extended for the new edition., Published by Elsevier, New York, NY [u.a.]

92. Development and recent evaluation of the MT_CKD model of continuum absorption.

Author

Mlawer EJ, Payne VH, Moncet JL, Delamere JS, Alvarado MJ, and Tobin DC

Abstract

Water vapour continuum absorption is an important contributor to the Earth's radiative cooling and energy balance. Here, we describe the development and status of the MT_CKD (MlawerTobinCloughKneizysDavies) water vapour continuum absorption model. The perspective adopted in developing the MT_CKD model has been to constrain the model so that it is consistent with quality analyses of spectral atmospheric and laboratory measurements of the foreign and self continuum. For field measurements, only cases for which the characterization of the atmospheric state has been highly scrutinized have been used. Continuum coefficients in spectral regions that have not been subject to compelling analyses are determined by a mathematical formulation of the spectral shape associated with each water vapour monomer line. This formulation, which is based on continuum values in spectral regions in which the coefficients are well constrained by measurements, is applied consistently to all water vapour monomer lines from the microwave to the visible. The results are summed-up (separately for the foreign and self) to obtain continuum coefficients from 0 to 20 000 cm(-1). For each water vapour line, the MT_CKD line shape formulation consists of two components: exponentially decaying far wings of the line plus a contribution from a water vapour molecule undergoing a weak interaction with a second molecule. In the MT_CKD model, the first component is the primary agent for the continuum between water vapour bands, while the second component is responsible for the majority of the continuum within water vapour bands. The MT_CKD model should be regarded as a semi-empirical model with strong constraints provided by the known physics. Keeping the MT_CKD continuum consistent with current observational studies necessitates periodic updates to the water vapour continuum coefficients. In addition to providing details on the MT_CKD line shape formulation, we describe the most recent update to the model, MT_CKD_2.5, which is based on an analysis of satellite- and ground-based observations from 2385 to 2600 cm(-1) (approx. 4 μm).

Published
2012
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