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Behnjamin J. Zib, Xiquan Dong, Baike Xi, and Aaron Kennedy

–land model uses an experimental version of the NCEP Global Forecast System (GFS) that includes an updated prognostic cloud condensate scheme ( Moorthi et al. 2001 ), revisions to the solar radiative transfer model ( Hou et al. 2002 ), and a Rapid Radiative Transfer Model (RRTM) developed at Atmospheric and Environmental Research for longwave radiative transfer ( Mlawer et al. 1997 ). Cloud liquid water is a prognostic quantity from which cloud fraction is diagnosed. Clouds are also assumed to be maximum

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Franklin R. Robertson and Jason B. Roberts

verification for the COARE algorithm . J. Climate , 16 , 571 – 591 . Frierson , D. M. W. , D. Kim , I.-S. Kang , M.-I. Lee , and J. Lin , 2011 : Structure of AGCM-simulated convectively coupled Kelvin waves and sensitivity to convective parameterization . J. Atmos. Sci. , 68 , 26 – 45 . Fu , Q. , K. N. Liou , M. C. Cribb , T. P. Charlock , and A. Grossman , 1997 : Multiple scattering parameterization in thermal infrared radiative transfer . J. Atmos. Sci. , 54 , 2799

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Derek J. Posselt, Andrew R. Jongeward, Chuan-Yuan Hsu, and Gerald L. Potter

distributed among all cloudy subcolumns. This assumption is valid if the cloud can be assumed to be horizontally uniform across the grid box. Grid boxes containing a mix of deep convective cores and stratiform anvil may have a highly nonuniform distribution of cloud mass, and we explore the sensitivity of the output to the assumed subgrid cloud mass distribution later in section 5 . Calculation of broadband longwave and shortwave radiative fluxes is performed using the Fu–Liou radiative transfer model

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Michele M. Rienecker, Max J. Suarez, Ronald Gelaro, Ricardo Todling, Julio Bacmeister, Emily Liu, Michael G. Bosilovich, Siegfried D. Schubert, Lawrence Takacs, Gi-Kong Kim, Stephen Bloom, Junye Chen, Douglas Collins, Austin Conaty, Arlindo da Silva, Wei Gu, Joanna Joiner, Randal D. Koster, Robert Lucchesi, Andrea Molod, Tommy Owens, Steven Pawson, Philip Pegion, Christopher R. Redder, Rolf Reichle, Franklin R. Robertson, Albert G. Ruddick, Meta Sienkiewicz, and Jack Woollen

Aqua . The assimilation of radiance data requires a forward radiative transfer model (RTM) as the observation operator, to calculate the model-equivalent radiances, and the corresponding Jacobian to calculate the influences in model space of the radiance increments calculated from the analysis. For this, the GSI is coupled to the Community Radiative Transfer Model (CRTM; Han et al. 2006 ; Chen et al. 2010 ). The CRTM employs the compact version of Optical Path Transmittance (OPTRAN) ( McMillin et

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Franklin R. Robertson, Michael G. Bosilovich, Junye Chen, and Timothy L. Miller

discontinuities further we turn first to monthly mean statistics of observation-minus-forecast (OMF) and observation-minus-analysis (OMA) residuals for the various AMSU-A channels of the NOAA polar orbiting suite. Simulated radiances based on the model 6-h forecast and analyzed fields are generated using the forward observation operator of the Community Radiative Transfer Model (CRTM) ( Han et al. 2006 ). The difference between the monthly mean values of OMF and OMA residuals, in turn, provides an estimate of

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Aaron D. Kennedy, Xiquan Dong, Baike Xi, Shaocheng Xie, Yunyan Zhang, and Junye Chen

aerosols on radiative transfer in NARR also need to be improved. Given that NARR is based on the NCEP Eta Model, this is consistent with Hinkelman et al. (1999) , who found that the Eta Model had an average excess of 50 W m −2 for SW-down, with approximately half of this bias attributed to deficient extinction. The comparisons between MERRA and ARM agree much better than those between NARR and ARM, as shown in Fig. 11 and listed in Table 2 . However, there are a few exceptions. MERRA has larger

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Michael G. Bosilovich, Franklin R. Robertson, and Junye Chen

discussion on the primary water and energy transfer processes, as well as recent quantitative assessments of various observational data and uncertainties. Even though the top of the atmosphere (TOA) radiative fluxes likely have the smallest uncertainties (order 5thinsp;W m −2 bias and, perhaps, an order of magnitude smaller in precision), refining this observational record is still an active area of research ( Loeb et al. 2009 ). Validating the observed water cycle observations through global balance

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Michael A. Brunke, Zhuo Wang, Xubin Zeng, Michael Bosilovich, and Chung-Lin Shie

accurate radiative transfer model . J. Atmos. Sci. , 44 , 859 – 876 . Saha , S. , and Coauthors , 2010 : The NCEP Climate Forecast System reanalysis . Bull. Amer. Meteor. Soc. , 91 , 1015 – 1057 . Schlüssel , P. , L. Schanz , and G. Englisch , 1995 : Retrieval of latent heat flux and longwave irradiance at the sea surface from SSM/I and AVHRR measurements . Adv. Space Res. , 16 , 107 – 116 . Schulz , J. , P. Schlüssel , and H. Grassl , 1993 : Water vapor in the

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Mark Decker, Michael A. Brunke, Zhuo Wang, Koichi Sakaguchi, Xubin Zeng, and Michael G. Bosilovich

large updates. Satellite radiances are directly assimilated while accounting for variational bias correction through the use of the Joint Center for Satellite Data Assimilation (JCSDA) community radiative transfer model. Unlike other reanalysis products, MERRA also assimilates instantaneous rain rate (precipitation) observations though the use of Special Sensor Microwave Imager (SSM/I) and the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) measurements. A key difference between

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Yonghong Yi, John S. Kimball, Lucas A. Jones, Rolf H. Reichle, and Kyle C. McDonald

.25° horizontal resolution (latitude × longitude) with 55 vertical levels. The new GEOS-5 system incorporates information from many modern Earth observations, including SSM/I radiances, Atmospheric Infrared Sounder (AIRS) radiances and scatterometer-based wind retrievals, and is expected to improve over existing reanalysis products. Moreover, GEOS-5 primarily assimilates satellite raw radiance values using the Community Radiative Transfer Model (CRTM) rather than satellite retrievals employed by GEOS-4

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