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Thomas P. Charlock and Timothy L. Alberta

Results from a temporally intensive, limited area, radiative transfer model experiment are on-line for investigating the vertical profile of shortwave and longwave radiative fluxes from the surface to the top of the atmosphere (TOA). The CERES/ARM/GEWEX Experiment (CAGEX) Version 1 provides a record of fluxes that have been computed with a radiative transfer code; the atmospheric sounding, aerosol, and satellite-retrieved cloud data on which the computations have been based; and surface-based measurements of radiative fluxes and cloud properties from ARM for comparison.

The computed broadband fluxes at TOA show considerable scatter when compared with fluxes that are inferred empirically from narrowband operational satellite data. At the surface, LW fluxes computed with an alternate sounding dataset compare well with pyrgeometer measurements. In agreement with earlier work, the authors find that the calculated SW surface insolation is larger than the measurements for clear-sky and total-sky conditions.

This experiment has been developed to test retrievals of radiative fluxes and the associated forcings by clouds, aerosols, surface properties, and water vapor. Collaboration is sought; the goal is to extend the domain of meteorological conditions for which such retrievals can be done accurately. CAGEX Version 1 covers April 1994. Subsequent versions will (a) at first span the same limited geographical area with data from October 1995, (b) then expand to cover a significant fraction of the GEWEX Continental-Scale International Project region for April 1996 through September 1996, and (c) eventually be used in a more advanced form to validate CERES.

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Mark. A. Miller and Anthony Slingo

The Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) was recently developed to enable collection of detailed climate data in locations not currently sampled by ARM's five fixed sites. The AMF includes a comprehensive suite of active and passive remote sensors, including cloud radar, that sample the atmosphere in a narrow column above its location. Surface radiation, aerosols, and fluxes are also measured and there is an ancillary measurement facility to help quantify local gradients. The AMF is deployed at no cost to the principal investigator or institution for periods from six months to one year on the basis of an international proposal competition judged by a nonpartisan board. The proposal to ARM that led to the initial international deployment of the AMF in Niamey, Niger, was titled “Radiative Atmospheric Divergence Using the AMF, GERB Data, and AMMA Stations (RADAGAST).” This paper provides a description of the instruments that compose the AMF, its charter, a description of its deployment in support of RADAGAST, and examples of data that have been collected in Africa.

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Shunlin Liang, Jie Cheng, Kun Jia, Bo Jiang, Qiang Liu, Zhiqiang Xiao, Yunjun Yao, Wenping Yuan, Xiaotong Zhang, Xiang Zhao, and Ji Zhou

temporally variable conversion factor determined from the GEWEX-SRB V3.0 radiative flux products, in which DSR and PAR are provided separately. The accuracy of this method is comparable to that of the previous version of the product. Cai et al. (2014) demonstrated that the GLASS PAR product can produce better estimations of terrestrial GPP over China by comparing it with several other incident radiation products. Broadband albedo. Land surface albedo describes the ratio of the upward to downward flux

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E. Carmack, I. Polyakov, L. Padman, I. Fer, E. Hunke, J. Hutchings, J. Jackson, D. Kelley, R. Kwok, C. Layton, H. Melling, D. Perovich, O. Persson, B. Ruddick, M.-L. Timmermans, J. Toole, T. Ross, S. Vavrus, and P. Winsor

first-year ice here than in the multiyear ice domain ( Melling et al. 2005 ). Ridged and multiyear ice. A quasi-equilibrium thickness for thermally conditioned multiyear ice is attained when the cold-season accretion of ice by conductive flux (which is inversely proportional to ice thickness) is matched by warm-season ablation due to radiative and oceanic fluxes (which are independent of its thickness) and, historically, is about 3 m for an average seasonal cycle of climatic forcing in the High

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A. J. Illingworth, H. W. Barker, A. Beljaars, M. Ceccaldi, H. Chepfer, N. Clerbaux, J. Cole, J. Delanoë, C. Domenech, D. P. Donovan, S. Fukuda, M. Hirakata, R. J. Hogan, A. Huenerbein, P. Kollias, T. Kubota, T. Nakajima, T. Y. Nakajima, T. Nishizawa, Y. Ohno, H. Okamoto, R. Oki, K. Sato, M. Satoh, M. W. Shephard, A. Velázquez-Blázquez, U. Wandinger, T. Wehr, and G.-J. van Zadelhoff

EarthCARE, a joint ESA–JAXA satellite to be launched in 2018, will provide global profiles of clouds, aerosols, and precipitation properties together with derived radiative fluxes and heating rates. The Earth Clouds, Aerosol and Radiation Explorer (EarthCARE) satellite is a joint mission by the European Space and Japanese Aerospace Exploration Agencies scheduled for launch in 2018. Data from its cloud profiling radar, with Doppler capability, high-spectral-resolution lidar, and multispectral

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Eric J. Jensen, Leonhard Pfister, David E. Jordan, Thaopaul V. Bui, Rei Ueyama, Hanwant B. Singh, Troy D. Thornberry, Andrew W. Rollins, Ru-Shan Gao, David W. Fahey, Karen H. Rosenlof, James W. Elkins, Glenn S. Diskin, Joshua P. DiGangi, R. Paul Lawson, Sarah Woods, Elliot L. Atlas, Maria A. Navarro Rodriguez, Steven C. Wofsy, Jasna Pittman, Charles G. Bardeen, Owen B. Toon, Bruce C. Kindel, Paul A. Newman, Matthew J. McGill, Dennis L. Hlavka, Leslie R. Lait, Mark R. Schoeberl, John W. Bergman, Henry B. Selkirk, M. Joan Alexander, Ji-Eun Kim, Boon H. Lim, Jochen Stutz, and Klaus Pfeilsticker

species, meteorological conditions, and radiative fluxes were included ( Table 1 ). Instruments were chosen based on proven techniques and size/weight accommodation on the Global Hawk. The very dry conditions present in the tropical tropopause region (H 2 O mixing ratios as low as ≃1 ppmv) represent a significant challenge for accurately measuring water vapor. Large, unresolved discrepancies between past water vapor concentrations measured with different instruments ( Oltmans and Rosenlof 2000

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Manfred Wendisch, Andreas Macke, André Ehrlich, Christof Lüpkes, Mario Mech, Dmitry Chechin, Klaus Dethloff, Carola Barrientos Velasco, Heiko Bozem, Marlen Brückner, Hans-Christian Clemen, Susanne Crewell, Tobias Donth, Regis Dupuy, Kerstin Ebell, Ulrike Egerer, Ronny Engelmann, Christa Engler, Oliver Eppers, Martin Gehrmann, Xianda Gong, Matthias Gottschalk, Christophe Gourbeyre, Hannes Griesche, Jörg Hartmann, Markus Hartmann, Bernd Heinold, Andreas Herber, Hartmut Herrmann, Georg Heygster, Peter Hoor, Soheila Jafariserajehlou, Evelyn Jäkel, Emma Järvinen, Olivier Jourdan, Udo Kästner, Simonas Kecorius, Erlend M. Knudsen, Franziska Köllner, Jan Kretzschmar, Luca Lelli, Delphine Leroy, Marion Maturilli, Linlu Mei, Stephan Mertes, Guillaume Mioche, Roland Neuber, Marcel Nicolaus, Tatiana Nomokonova, Justus Notholt, Mathias Palm, Manuela van Pinxteren, Johannes Quaas, Philipp Richter, Elena Ruiz-Donoso, Michael Schäfer, Katja Schmieder, Martin Schnaiter, Johannes Schneider, Alfons Schwarzenböck, Patric Seifert, Matthew D. Shupe, Holger Siebert, Gunnar Spreen, Johannes Stapf, Frank Stratmann, Teresa Vogl, André Welti, Heike Wex, Alfred Wiedensohler, Marco Zanatta, and Sebastian Zeppenfeld

energy fluxes and sea ice dynamics. Table 1. Examples of major campaigns focused on atmospheric and surface processes performed in the Arctic; the list is not complete. These past campaigns generally highlighted the important role that clouds can—and do— play in that changing system and in the manifestation of Arctic amplification. However, there is still a basic lack of understanding of the interplay between aerosol particles, clouds, and surface properties, as well as turbulent and radiative

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D. H. Bromwich, A. B. Wilson, L. Bai, Z. Liu, M. Barlage, C.-F. Shih, S. Maldonado, K. M. Hines, S.-H. Wang, J. Woollen, B. Kuo, H.-C. Lin, T.-K. Wee, M. C. Serreze, and J. E. Walsh

the climate-model-ready update to the global climate model (GCM) version of the Rapid Radiative Transfer Model (RRTMG) for longwave (LW) and shortwave (SW) radiation ( Clough et al. 2005 ; Iacono et al. 2008 ). Different from ASRv1, however, we implement the new subgrid-scale cloud fraction interaction with radiation that allows for more realistic shortwave and longwave, improving additional weather parameters ( Alapaty et al. 2012 ; Zheng et al. 2016 ). The Noah LSM ( Chen and Dudhia 2001 ) and

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J. T. Kiehl and Kevin E. Trenberth

The purpose of this paper is to put forward a new estimate, in the context of previous assessments, of the annual global mean energy budget. A description is provided of the source of each component to this budget. The top-of-atmosphere shortwave and longwave flux of energy is constrained by satellite observations. Partitioning of the radiative energy throughout the atmosphere is achieved through the use of detailed radiation models for both the longwave and shortwave spectral regions. Spectral features of shortwave and longwave fluxes at both the top and surface of the earth's system are presented. The longwave radiative forcing of the climate system for both clear (125 W m−2) and cloudy (155 W m−2) conditions are discussed. The authors find that for the clear sky case the contribution due to water vapor to the total longwave radiative forcing is 75 W m−2, while for carbon dioxide it is 32 W m−2. Clouds alter these values, and the effects of clouds on both the longwave and shortwave budget are addressed. In particular, the shielding effect by clouds on absorption and emission by water vapor is as large as the direct cloud forcing. Because the net surface heat budget must balance, the radiative fluxes constrain the sum of the sensible and latent heat fluxes, which can also be estimated independently.

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Bruce A. Wielicki, Bruce R. Barkstrom, Edwin F. Harrison, Robert B. Lee III, G. Louis Smith, and John E. Cooper

Clouds and the Earth's Radiant Energy System (CERES) is an investigation to examine the role of cloud/radiation feedback in the Earth's climate system. The CERES broadband scanning radiometers are an improved version of the Earth Radiation Budget Experiment (ERBE) radiometers. The CERES instruments will fly on several National Aeronautics and Space Administration Earth Observing System (EOS) satellites starting in 1998 and extending over at least 15 years. The CERES science investigations will provide data to extend the ERBE climate record of top-of-atmosphere shortwave (SW) and longwave (LW) radiative fluxes. CERES will also combine simultaneous cloud property data derived using EOS narrowband imagers to provide a consistent set of cloud/radiation data, including SW and LW radiative fluxes at the surface and at several selected levels within the atmosphere. CERES data are expected to provide top-of-atmosphere radiative fluxes with a factor of 2 to 3 less error than the ERBE data. Estimates of radiative fluxes at the surface and especially within the atmosphere will be a much greater challenge but should also show significant improvements over current capabilities.

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