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Gang Zhang, Kerry H. Cook, and Edward K. Vizy

heat of water vaporization, q is the specific humidity, g is the gravity acceleration, and z is the geopotential height. MSE increasing with altitude indicates a stable atmosphere. Analysis of the MSE allows one to distinguish between the roles of temperature and moisture variations in changing atmospheric stability properties. MSE analysis is widely used in studying instability associated with rainfall (e.g., Pu and Cook 2012 ; Neupane and Cook 2013 ). Figure 8a displays profiles of MSE

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Lisa Hannak, Peter Knippertz, Andreas H. Fink, Anke Kniffka, and Gregor Pante

occasionally grow deep enough to produce significant precipitation. Through the strong contrast in brightness to the underlying densely vegetated areas, the low clouds have a substantial impact on the radiation balance at the surface and therefore determine the diurnal cycle of the planetary boundary layer (PBL) (e.g., Gounou et al. 2012 ). Related changes in surface gradients of equivalent potential temperature may have an impact on larger scales. For example, Zheng and Eltahir (1998) showed that the

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Gang Zhang, Kerry H. Cook, and Edward K. Vizy

other parameterizations remain in the model. Most relevant to the production of rainfall, these parameterizations include schemes for determining heat, moisture, and momentum transport from the planetary boundary layer (PBL) and calculations of the cloud microphysics. As described in section 3 , two sensitivity simulations using different PBL and cloud microphysics schemes are used to evaluate the dependence of the default simulation on these parameterizations. Here we note that results shown in

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Kerry H. Cook and Edward K. Vizy

physical processes of the precipitation changes that are responsible for those reductions. 3. Model simulations and evaluation The National Oceanic and Atmospheric Administration (NOAA)/National Center for Atmospheric Research (NCAR) Weather Research and Forecasting (WRF; Skamarock et al. 2005 ) regional model, version 3.1.1, is used with 32 vertical levels, 90-km horizontal resolution, and a time step of 3 min. The top of the atmosphere is set at 20 hPa. Figure 2 shows the full model domain with

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Wassila M. Thiaw and Vadlamani B. Kumar

predictability for this time range. This includes the realization of a better representation of the MJO in numerical weather and climate models ( Rashid et al. 2011 ) and the recent acceleration of the development of tools to monitor and predict the MJO and its impacts on the global climate. The MJO is a coupled ocean–atmosphere planetary wavenumber-1 to -3 pattern that propagates from west to east around the globe ( Madden and Julian 1972 , 1994 ). It exhibits an area of enhanced rainfall activity

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Irenea L. Corporal-Lodangco, Lance M. Leslie, and Peter J. Lamb

. El Niño–Southern Oscillation (ENSO) is a tropical atmosphere–ocean interaction that modifies the thermodynamic and dynamic states that influence the weather and climate system ( Bjerknes 1969 ). Kim et al. (2008) consider it to be the most important planetary-scale phenomenon affecting interannual variations in TC activity in the WNP. The relationship between ENSO and TC activity in the WNP has been explored extensively in previous studies (e.g., Chan 1985 , 2000 ; Dong 1988 ; Lander 1993

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