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P. R. Field, A. Gettelman, R. B. Neale, R. Wood, P. J. Rasch, and H. Morrison

first comparison between composite satellite and composite model output of midlatitude cyclones using the European Centre for Medium-Range Weather Forecasts model. In this study we use a cyclone-relative compositing approach to assess the ability of the Community Atmosphere Model, version 3 (CAM3) to accurately represent the spatial structure of midlatitude cyclones and their dependence upon their thermodynamic and dynamic environment. Previous comparisons of satellite data and global model output

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Daehyun Kim, Adam H. Sobel, Eric D. Maloney, Dargan M. W. Frierson, and In-Sik Kang

Center for Atmospheric Research (NCAR)], in which the same configurations are used except for one parameter in the cumulus parameterization. The Tokioka modification ( Tokioka et al. 1988 ), which suppresses convective plumes with entrainment rates less than a threshold that varies inversely with planetary boundary layer (PBL) depth, is implemented in AM2 and SNU with different threshold values. In that modification, the threshold value is defined as μ min = α / D , where D is the depth of the

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J. Boé and L. Terray

shown that an important part of the changes in winter precipitation for the Iberian Peninsula can be explained by the modification of the occurrence frequency of a few weather types (WTs). Others studies have come to a similar conclusion [see, e.g., Paredes et al. (2006) , regarding March precipitation in Spain and Portugal]. The causes of the changes in LSC over Europe remain unclear. It is not known whether these changes simply are due to natural climate variability ( Stephenson et al. 2000 ) or

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William D. Collins

the European Center for Medium–Range Weather Forecasts (ECMWF) reanalysis (ERA), the solar absorption is increased by modifications to the parameterization of shortwave radiative transfer ( Wild et al. 1998a ; Wild et al. 1998b ). The spectral resolution of the shortwave calculations is reduced to two bands for visible and near-infrared wavelengths. The same code is used in the ECMWF/Hamburg (ECHAM) GCM, version 4. The coarse spectral resolution can introduce spurious cloud absorption ( Slingo

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M. Georgescu

for nearly one-third of the 15 million additional state inhabitants ( California Department of Finance 2013 ). Modification of large swaths of existing California landscapes to urban areas raises regional climate concerns for future residents. Fig . 1. Landscape representation for (a) Control (using ICLUS as 2000 urban representation) and (b) ICLUS_A2 denoting 2100 urban expansion. Urban environments, perhaps the most evident expression of land-use and land-cover change, are recognized as major

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F. Justino, A. S. Silva, M. P. Pereira, F. Stordal, D. Lindemann, and F. Kucharski

primarily induced by changes in the configuration of the astronomical forcing (e.g., Scherer et al. 2008 ). Recently, the influence of the atmospheric CO 2 concentration in leading the onset of the Antarctic glaciation has also been explored ( DeConto and Pollard 2003 ). DeConto et al. (2007) argued that once ice sheets are established, seasonal sea ice distribution is highly sensitive to astronomical forcing and ice sheet geometry due to modification of the regional temperature and low-level winds

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Julio T. Bacmeister, Michael F. Wehner, Richard B. Neale, Andrew Gettelman, Cecile Hannay, Peter H. Lauritzen, Julie M. Caron, and John E. Truesdale

successes and shortcomings of CAM runs at high resolutions (for climate studies) of 25 km. The paper is organized as follows. Section 2 describes the model configurations, experimental setups, and verification data used in this study. Modifications made to the model configurations for high-resolution runs are explained. Section 3 examines top-of-the-atmosphere radiation fluxes and their sensitivities to resolution. Section 4 discusses basic model climatologies of several key simulation parameters

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Ramon A. Quintana-Gomez

( HIMAT 1993 ). Other sources of data such as the World Weather Records 1941–60 (1966) and the Great Britain Meteorological Office’s Reséau Mondial 1910–34 ( Great Britain Meteorological Office 1957 ) were also used. A network of 41 stations was chosen for initial evaluation, and based on the amount of missing data, 14 stations were retained for homogeneity testing ( Table 1 ). The data for these stations were then subjected to the Alexandersson’s (1986 , 1995) test of homogeneity, prior to

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Roman Brogli, Nico Kröner, Silje Lund Sørland, Daniel Lüthi, and Christoph Schär

apply the sequential factor separation method ( Schär and Kröner 2017 ). This means that CCLM’s lateral boundaries are modified by adding or removing a part of the climate change signal simulated by the GCMs and analyzing the effect of this specific contribution in the RCM simulations. Following Kröner et al. (2017) , we add a modification to the lateral boundaries of a simulation of the CTRL period, and additionally, we remove the same modification from the lateral boundaries of a SCEN simulation

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Barry D. Keim and James F. Cruise

1990 over a 76.2-mm threshold recorded at Covington, Louisiana ( Keim 1996 ). Data can also be truncated on other criteria such as exceedences of two or three standard deviations ( Ratcliffe et al. 1978 ) or by partial duration series, among others. With the Covington storm data, trends are investigated after partitioning the data into three synoptic weather types; fronts, tropical disturbances, and air masses. Use of this classification scheme for storms is well documented in the literature (i

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