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Christopher J. Anderson, Raymond W. Arritt, and John S. Kain

have altered the profile of feedback of cloud liquid water and cloud ice in the Kain–Fritsch2 (KF2; Kain 2004 ) parameterization to the grid-resolved variables acted upon by the bulk microphysics parameterization. We have tested the effects of these modifications and their sensitivity to horizontal resolution in a matrix of experimental simulations of the June–July 1993 flood in the central United States. During this period many MCSs were observed over the same region, and they occurred almost

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James B. Polly and William B. Rossow

1. Introduction Cloud processes in extratropical cyclones lie at the intersection of the well-developed theory of dry baroclinic waves and feedbacks on the dynamics by diabatic heating due to radiation and precipitation. The interaction between waves and clouds is a major source of uncertainty in climate and weather prediction ( Bony et al. 2006 ). Baroclinic waves play a key role in the meridional transport of energy and water ( Peixoto and Oort 1992 ), and the effects of cloud heating on

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Chunxi Zhang, Yuqing Wang, Kevin Hamilton, and Axel Lauer

motivated by the desire to provide local-scale climate change projections consistent with global coupled ocean–atmosphere model results (e.g., Mearns et al. 2012 ). This “dynamical downscaling” via regional comprehensive models is also potentially useful for seasonal climate prediction. In addition, retrospective simulations with limited-area models forced by observed boundary conditions could find application in understanding and modeling the finescale dependence of aspects of the local environment

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Clare Webster, Nick Rutter, Franziska Zahner, and Tobias Jonas

) longwave enhancement for (a),(b) the distributed and rail comparison; (c),(d) the stationary distributed and linear comparison; and (e),(f) the linear and rail comparison across the four study periods. Statistical analyses of the three comparisons also showed seasonal variation, particularly in shortwave transmissivity measurements ( Fig. 3 ). Both the mean and the coefficient of variation (CV) of the differences between transmissivity measurements were lowest in the autumn and winter (mean differences

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T. S. Hudson, A. Horseman, and J. Sugier

, since it provides a consistent foundation for the comparison of diurnal, seasonal, and solar cycle variations of virtual ionosphere height and the related effects upon interference minima positions for a lightning detection system, something that has not previously been undertaken. Further to this, a VLF propagation model has now been developed, and is briefly detailed in this paper, that provides additional insight into the location of these minima and can be used to estimate the ionosphere height

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Tony Huiquan Zhang

likely to happen during good weather, and this effect should remain significant with seasonal patterns controlled for. The paper also links resource mobilization theory and political opportunity theory ( McCarthy and Zald 1977 ; Meyer 2004 ; Jenkins 1983 ; Tarrow 2011 ) to the discussion of the weather effects. The speculation is that weather matters more when there are more political opportunities and resources for mobilization are available, considering social movement activists have more

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Christopher J. Cox, Taneil Uttal, Charles N. Long, Matthew D. Shupe, Robert S. Stone, and Sandy Starkweather

the seasonal cycle in CRF found in the literature (refer to section 3b ). In this study, we focus on a single location (Barrow) chosen because of its long surface-based observational record positioned in what may be a significant pathway for advecting energy into the Arctic during the critical time of year for preconditioning the ice. The important spring transition in longwave and shortwave cloud radiative effects is dependent on solar zenith angle and thus latitude. Barrow’s latitude is at the

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Motoki Nagura and Yukio Masumoto

to the equator. Their results agreed well with observations in the upstream region of the island but not in the downstream region. White (1971a) considered both nonlinearity and the rotational effects in his steady barotropic model, in which uniform background zonal flow hits a circular island. He referred to the resulting wake as a Rossby wake to distinguish it from a von Kármán wake ( von Kármán 1911 ). The idea of the Rossby wake is suggestive, but it is unlikely for his theory to be

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Shinya Shimokawa and Tomonori Matsuura

that stable antisymmetric inertial subgyres appeared for some wind stress strengths and can be explained by an analytical modon solution. Thus far, most studies of double gyres using middle-range complexity have been conducted under constant (time independent) wind forcing. In the real atmosphere and oceans, seasonal wind forcing with westerly and trade winds generates subtropical and subpolar gyres arising from western boundary currents and internal currents. Recently, Sakamoto (2006) showed

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Thomas A. Guinn, Daniel J. Halperin, and Christopher G. Herbster

awareness in understanding the magnitude and seasonal variability of altimeter errors resulting from nonstandard temperatures. To help to improve pilot awareness of potential altimeter errors, Guinn and Mosher (2015) created model-based current and forecast “corrected” D -value images to visualize estimated altimeter error resulting from nonstandard temperatures using real-time North American Mesoscale Forecast System (NAM) model output. The traditional D value (or altimeter correction), first

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