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Peter Vogel, Peter Knippertz, Andreas H. Fink, Andreas Schlueter, and Tilmann Gneiting

most recent days for which data are available at the initialization time. We use a local neighborhood approach with n = 500 training days such that for each TRMM pixel its past 500 forecast–observation-pairs as well as the forecast–observation-pairs of eight adjacent grid boxes are used for training data composition. Near coasts the eight nearest grid boxes that belong to the land–sea class of the original point are considered. Parameter estimation is then based on CRPS minimization over the

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Stephan Rasp, Tobias Selz, and George C. Craig

second moment can be expressed in terms of the normalized variance or in terms of the unnormalized standard deviation b. Previous tests of the CC06 theory So far, few studies have directly tested the assumptions and predictions of CC06. Cohen and Craig (2006) used a convection-permitting model in a radiative–convective equilibrium setup with different large-scale forcing and vertical wind shear strengths and found that p ( m ) was well approximated by an exponential distribution for all settings

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Joël Arnault, Thomas Rummler, Florian Baur, Sebastian Lerch, Sven Wagner, Benjamin Fersch, Zhenyu Zhang, Noah Kerandi, Christian Keil, and Harald Kunstmann

objectives, including the models used, the ensemble strategy, the observational validation dataset, and quantitative metrics, is detailed in section 2 . Results are given in section 3 , and a summary and perspective are finally provided in section 4 . 2. Method a. Modeling approach: WRF and WRF-Hydro setups The WRF Model ( Skamarock and Klemp 2008 ) and the hydrologically enhanced version of WRF, that is, WRF-Hydro ( Gochis et al. 2015 ), are used to simulate the regional land–atmosphere system over

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Hilke S. Lentink, Christian M. Grams, Michael Riemer, and Sarah C. Jones

3). So, when ET takes place over the ocean, the structure of the storm is changing from an almost axisymmetric warm-core cyclone into a frontal cold-core cyclone with extratropical characteristics such as a broadening low-level wind field. Although ET is most common over the ocean ( Evans et al. 2017 ), the transition can take place near land and orography, like Japan, New Zealand, or the U.S. East Coast. When recurving TCs are close to a coastal mountainous area, enhanced precipitation is often

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Tobias Selz

background spectrum and thus likely involve a climatological component. For example, orography and the land–sea distribution may hinder the largest planetary waves from freely evolving. In addition the ICON simulations have fixed sea surface temperatures. d. Comparison to simulations with a deterministic convection scheme A second set of simulations has been performed using the ICON model but this time in its standard setup with the deterministic TB convection scheme ( Bechtold et al. 2001 ). With this

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Tobias Selz, Lucas Fischer, and George C. Craig

. 1999 ), increasing exponents with height ( Tjemkes and Visser 1994 ; Kahn et al. 2011 ), boundary layer versus free troposphere ( Cho et al. 2000 ; Pressel and Collins 2012 ), and anisotropic scaling ( Lovejoy et al. 2010 ). The implications of the different observed exponents for the existence of universal power laws are not clear, since the data used in each case are limited, and the results may not be comparable. It is, however, interesting to consider whether distinct physical mechanisms may

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Andreas Schlueter, Andreas H. Fink, Peter Knippertz, and Peter Vogel

. Quart. J. Roy. Meteor. Soc. , 132 , 195 – 212 , . 10.1256/qj.04.153 Tseng , W.-L. , H.-H. Hsu , N. Keenlyside , C.-W. J. Chang , B.-J. Tsuang , C.-Y. Tu , and L.-C. Jiang , 2017 : Effects of surface orography and land–sea contrast on the Madden–Julian oscillation in the Maritime Continent: A numerical study using ECHAM5-SIT . J. Climate , 30 , 9725 – 9741 , . 10.1175/JCLI-D-17-0051.1 Tulich , S. N

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Kirstin Kober and George C. Craig

of moisture and temperature in the atmosphere determines the amount of CAPE and is influenced by several processes, especially in the atmospheric boundary layer. Soil type, land use, orography, and elevation are important because they define properties of the interaction between the land surface and the atmosphere. Several processes contribute to create variability in a convective boundary layer. The heating of surfaces with different heat conduction properties by the sun causes turbulent eddies

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Thomas Engel, Andreas H. Fink, Peter Knippertz, Gregor Pante, and Jan Bliefernicht

, 95 years, 1919–2014) (for locations see Fig. 1a ). While for Dakar only one rain gauge was available to the authors for the extreme event in August 2012, 42 additional stations with more than 80% of daily rainfall observations during the period 1983–2010, and thus including the September 2009 event, were available for Burkina Faso. These Burkinabe data were collected in the framework of the West African Science Service Center on Climate Change and Adapted Land Use (WASCAL) project ( www

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Mirjam Hirt, Stephan Rasp, Ulrich Blahak, and George C. Craig

inhibition layer. Because boundary layer turbulence parameterizations typically only represent the mean mixing caused by subgrid eddies in a deterministic way, models can exhibit biases caused by an incorrect coupling between subgrid processes and resolved convection. In particular, this has been observed in the Consortium for Small-Scale Modeling (COSMO) model, which we are using in this study ( Keil et al. 2014 ; Baldauf et al. 2011 ; Craig et al. 2012 ). This inconsistency becomes particularly

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