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Robert Paul d'Entremont and Gary B. Gustafson

, plans call for the SERCAA model to replace the current U.S. Air Force (USAF) operational cloud analysis model, the Real-Time Nephanalysis (RTNEPH), in the summer of 2002. In the coming years, archived cloud analyses from this model will offer an alternative global cloud record for climate studies. As such, it is important to document and describe the retrieval technique in order to better understand and use its cloud products. The RTNEPH operates on two-channel data, generally obtained from Defense

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L. S. Rose, J. A. Stallins, and M. L. Bentley

. Multicity comparisons spanning a range of climates would provide insight into how background aerosol loads interact with urban influences ( Van Den Heever and Cotton 2007 ). Although flash events with weak synoptic forcing were examined in our study, strongly forced convection may also be affected by the urban environment ( Niyogi et al. 2006 ). Other causal factors to consider include cloud-base heights, cloud vertical development, precipitation rates and reflectivities, all interrelated parameters

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Hector Chikoore and Mark R. Jury

( Anyamba 1992 ) detected a 40–50-day oscillation and a more dominant 20–35-day oscillation in OLR anomalies over the tropical western Indian Ocean, with eastward propagation linked to the tropical MJO. Many studies have described interannual rainfall variability over southern Africa and its remote forcing, but intraseasonal characteristics have received less attention. The objective of this paper is to establish the intraseasonal spatial distribution and temporal variability of rainfall and

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Y. C. Sud, G. K. Walker, V. M. Mehta, and William K-M. Lau

drag, and a few new upgrades to land surface and cloud dynamical and microphysical processes. This version of the GCM has two recent additions that are significant. One is the prognostic cloud-radiative forcing (CRF) invoked through the use of the microphysics of clouds with relaxed Arakawa–Schubert scheme (McRAS) ( Sud and Walker, 1999a ; Sud and Walker, 1999b ; discussed in section 2.1 ). This upgrade is particularly relevant for assessing the influence of interactive clouds. The second upgrade

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Brandon J. Vogt

1. Introduction and background Lightning attachment to the ground is “one of the least understood and most poorly documented processes of the cloud-to-ground lightning discharge.” ( Rakov and Uman 2003 , p. 137). Whereas much of research on lightning attachment theory has taken place in a research domain dominated by laboratory-based numerical modeling, controlled simulation, and monitoring of individual lightning strikes at specialized field facilities, this paper uses remotely

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Walter N. Meier, James A. Maslanik, Charles W. Fowler, and Jeffrey R. Key

1. Introduction The polar regions play an important role in the global climate due in part to the effects of sea ice and cloud cover on albedo and energy transfer. Turbulent heat fluxes during winter and solar energy absorbed by the ocean in summer are controlled largely by the open-water area and lead fraction in the ice pack, while radiative fluxes are regulated primarily by solar insolation, cloud properties, and surface albedo/emissivity. Efforts to gain a better understanding of these

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Arindam Samanta, Bruce T. Anderson, Sangram Ganguly, Yuri Knyazikhin, Ramakrishna R. Nemani, and Ranga B. Myneni

radiative forcing ( Cess et al. 1996 ), which is a measure of the impact of clouds upon the top-of-atmosphere (TOA) radiation balance. The net effect of clouds is to cool the simulated climate system ( Kiehl et al. 2006 ), with increased cooling under warmer climates and reduced cooling under colder climates ( Figure 2b ). Overall, though, the cloud radiative forcing adjusts quasi-linearly with surface temperature as well. Clear-sky feedbacks can be estimated using the approach in Forster and Taylor

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Bharat Rastogi, A. Park Williams, Douglas T. Fischer, Sam F. Iacobellis, Kathryn McEachern, Leila Carvalho, Charles Jones, Sara A. Baguskas, and Christopher J. Still

1. Introduction Low-lying stratocumulus clouds and fog have been known to modify biophysical and ecological properties in a variety of ecosystems in differing climates. These include montane cloud forests in the tropics, which are dependent on frequent and prolonged immersion in the cloud layer ( Still et al. 1999 ), as well as in temperate regions such as the Appalachian Mountains in northeastern America, where the shift from low elevation deciduous to high elevation coniferous forests is

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Peiyun Zhu, Susan J. Cheng, Zachary Butterfield, Gretchen Keppel-Aleks, and Allison L. Steiner

.agrformet.2008.05.014 Alton , P. B. , P. R. North , and S. O. Los , 2007 : The impact of diffuse sunlight on canopy light-use efficiency, gross photosynthetic product and net ecosystem exchange in three forest biomes . Global Change Biol. , 13 , 776 – 787 , . 10.1111/j.1365-2486.2007.01316.x Andrews , T. , J. M. Gregory , P. M. Forster , and M. J. Webb , 2012 : Cloud adjustment and its role in CO 2 radiative forcing and climate

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J. Marshall Shepherd

spacecraft) for Houston, Texas, indicates that urban landscapes are far from homogeneous and simple ( Figure 8 ). Also, many of these studies did not specifically focus on the linkages of the forcing mechanisms to precipitation processes and often used minimal or simple cloud microphysical parameterizations. Recent modeling results by the author have employed a modified version of the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model ( Grell et al

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