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Peter J. Marinescu, Susan C. van den Heever, Max Heikenfeld, Andrew I. Barrett, Christian Barthlott, Corinna Hoose, Jiwen Fan, Ann M. Fridlind, Toshi Matsui, Annette K. Miltenberger, Philip Stier, Benoit Vie, Bethan A. White, and Yuwei Zhang

also vary, particularly in CCN-limited regimes (e.g., Reutter et al. 2009 ), which then may have many subsequent feedbacks on a cloud’s characteristics and evolution (e.g., Twomey 1977 ; Albrecht 1989 ). Typically, the majority of CCN are ingested through the bases of deep convective clouds within the atmospheric boundary layer, although several studies have shown that some fraction of CCN in the middle troposphere can also become entrained within deep convective updrafts, form cloud droplets

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Jie Peng, Zhanqing Li, Hua Zhang, Jianjun Liu, and Maureen Cribb

plain in central China, Yang et al. (2013a , b) found that both orographic precipitation and summer thunderstorms were suppressed by aerosols. Camponogara et al. (2014) also found that rainfall over the La Plata basin was suppressed by aerosols. As a result of rain suppression, clouds made up of smaller droplets may reach higher levels in the atmosphere. Once the freezing level is reached, ice processes begin, and more latent heat is released to invigorate the vertical development of the cloud

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Wojciech W. Grabowski

regime change; this does not apply to the case considered here.) The forcings refer to a prescribed initial meteorological situation (e.g., the sounding), surface sensible and latent heat fluxes, radiative cooling of the atmosphere, and the large-scale advection of temperature and moisture. The latter can be included through realistic lateral boundary conditions [as in typical limited-area numerical weather prediction (NWP) simulations] or through prescribed tendencies imposed over a finite

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Wojciech W. Grabowski and Hugh Morrison

approach because differences between ensemble members are large in the second half of the simulations. For illustration, Fig. 2 shows snapshots of the top of the atmosphere (TOA) albedo for randomly selected D-PRI (left column) and D-POL (right column) simulations for hours 2, 6, and 10. In agreement with the cloud fraction profiles in Fig. 1 (and maps of the liquid plus ice water path in Fig. 2 of G15 ), only shallow and optically thin cumuli are present at hour 2. Because the two simulations

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Yvonne Boose, Zamin A. Kanji, Monika Kohn, Berko Sierau, Assaf Zipori, Ian Crawford, Gary Lloyd, Nicolas Bukowiecki, Erik Herrmann, Piotr Kupiszewski, Martin Steinbacher, and Ulrike Lohmann

1. Introduction The ice phase in clouds remains one of the largest challenges in predicting Earth’s radiative budget accurately ( Boucher et al. 2013 ). In the atmosphere, pure water freezes homogeneously at temperatures below 235 K ( Lamb and Verlinde 2011 ). In mixed-phase clouds, temperatures are warmer, and supercooled water and ice coexist. Here, ice formation is initiated heterogeneously by ice nucleating particles (INPs), which represent only a small fraction of ambient aerosol particles

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Yun Lin, Yuan Wang, Bowen Pan, Jiaxi Hu, Yangang Liu, and Renyi Zhang

significant at 95% under the polluted condition (Pollu runs). Figure 3c and Fig. 4 (the middle three columns) exhibit the dependence of DCC microphysics on aerosol loadings. With AME only, the raindrop mass mixing ratio of the DCC is insensitive to the aerosol concentration, distinct from the shallow cumuli. In our microphysics scheme, graupel below the freezing level are assumed to be completely melted ( Li et al. 2008b ), producing additional rainwater to compensate the loss due to the inhibited

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Jiwen Fan, Yuan Wang, Daniel Rosenfeld, and Xiaohong Liu

1. Introduction Clouds regulate surface precipitation and the atmosphere’s radiative balance, therefore playing a significant role in the climate system. Clouds generally form when air is cooled and becomes supersaturated with respect to water or ice (except funnel clouds). The excess vapor generally cannot form cloud particles spontaneously owing to a high energy barrier, but rather condenses on aerosol particles that serve as either cloud condensation nuclei (CCN) or ice nuclei (IN

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Stacey Kawecki, Geoffrey M. Henebry, and Allison L. Steiner

pools and environmental wind shear ( Rotunno et al. 1988 ). Cold pools are an important aspect of squall-line development and propagation and are defined as evaporatively cooled areas of downdraft air that spread out horizontally underneath a precipitating cloud ( Engerer et al. 2008 ). Their strength is determined by the environment of the middle troposphere, the temperature and humidity stratification ( Alfaro and Khairoutdinov 2015 ), and by microphysical processes within the cloud, such as

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Eyal Ilotoviz, Alexander P. Khain, Nir Benmoshe, Vaughan T. J. Phillips, and Alexander V. Ryzhkov

2D, which simplified the prescription of the background wind profile in the 2D model. The wind speed increased with height from ~10 m s −1 in the lower atmosphere to about 20 m s −1 at levels of 100–200 hPa. In Villingen-Schwenningen, the daily maximum air temperature near the surface reached 22.9°C at 1500 UTC. The value of CAPE calculated using available sounding was comparatively low (from 759 to ~1240 J kg −1 ), but given the temporal and spatial delay and the observed temperature maximum

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