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Linda Schlemmer, Cathy Hohenegger, Jürg Schmidli, Christopher S. Bretherton, and Christoph Schär

for moister and more unstable soundings. The transition from shallow to deep convection also occurred earlier in these cases. The aim of the current study is to investigate the sensitivity of moist convection over land to atmospheric stability and humidity. We extend previous work by using a full set of parameterizations including radiation, boundary layer processes, and a soil model to calculate surface heat and moisture fluxes. This setup allows the study of the coupled land surface

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David G. Dewitt, Edwin K. Schneider, and Anandu D. Vernekar

precipitation, while the anomalyin condensational heating leads to divergence in thisregion and hence a decrease in precipitation. Cook (1994) used a series of idealized flat-landGCM experiments to explore the factors contributingto the east-west asymmetry of precipitation observedover tropical land masses in boreal summer. Cook(1994) found that along the axis of maximum precipitation (the ITCZ) for the idealized land area, the dryconvective adjustment forces low-level conw;rgenceacross the continent

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Xiaoming Sun and Ana P. Barros

. In contrast with the central Himalayas, where land-use and land-cover change (LULCC) has severely reduced the density and connectedness of vegetation, the eastern slopes of the Andes are densely forested; therefore, it is expected that the ET contribution to the atmospheric moisture supply should be significant. This local effect was highlighted by Wei and Dirmeyer (2012) , who conducted a diagnostic study to characterize the local versus remote impacts of soil moisture on precipitation [Eq. (1

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Fuzhong Weng and Quanhua Liu

). For surfaces such as snow, desert, and vegetation, volumetric scattering was calculated using a two-stream radiative transfer approximation. In the case of vegetation, geometrical optics are used since the leaf size is typically larger than the wavelength. For snow and deserts, a dense medium theory was adopted to take into account the coherent scattering by closely spaced particles. Figures 4a and 4b display the emissivity spectra obtained from the land emissivity model ( Weng et al. 2001 ). The

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Wesley Berg, William Olson, Ralph Ferraro, Steven J. Goodman, and Frank J. LaFontaine

1. Introduction The Special Sensor Microwave/Imager (SSM/I), which was initially launched onboard a Defense Meteorological Satellite Program (DMSP) spacecraft in June of 1987, was the first operational sensor for rainfall retrieval using passive microwave technology. SSM/I was also the first sensor with channels at 85 GHz, providing scattering information for land-based retrievals. Rain rate is one of several parameters identified as essential to the mission of the Department of Defense. Prior

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Takao Yoshikane and Fujio Kimura

distribution of sea surface temperature and surface process of land over the Southern Hemisphere. Matthews et al. (1996) indicated that the SPCZ is strongly influenced by the Madden–Julian oscillation (MJO) and explained the formation mechanism of the SPCZ using an idealized numerical model as follows. 1) Convection over the tropical region around Indonesia leads to an upper-tropospheric anticyclone above that region. 2) By interaction with the anticyclone, meandering of the subtropical jet is

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Mónica Zamora Zapata, Joel R. Norris, and Jan Kleissl

moister free-troposphere, and lower sea level pressure (SLP) ( Klein et al. 1995 ; Seethala et al. 2015 ). Research has been less extensive over coastal land, where earlier dissipation has been linked to smaller Bowen ratio (Bo; the ratio between sensible and latent heat fluxes over land) and weaker sea-breeze advection using simple sensitivity analyses ( Ghonima et al. 2016 ; Akyurek and Kleissl 2017 ). Most factors do not contribute independently to cloud dissipation because they are interrelated

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Youtong Zheng, Daniel Rosenfeld, and Zhanqing Li

(24 March, 25 June, and 2 February 2013) are presented. The vertical red lines in the left panels mark the Suomi-NPP satellite overpass time in order to temporally match the land surface temperature retrieved by VIIRS. As denoted by the boxes in the height–time displays of lidar vertical velocity data ( Figs. 2a,c,e ), 1-h Doppler lidar pixels of vertical velocity within 200-m layers were used to calculate the updraft velocity using Eq. (6) . In cloudy conditions, we selected a 2-h (rather than

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T. P. Barnett, L. Dümenil, U. Schlese, E. Roeckner, and M. Latif

also shows the spatial complexity of the flux fields. The total surface heat balance (S + IR + Qr + Qs)is positive for regions of active snow melt, typically20-40 W m-2 (Fig. 17 ).2 Instead of warming the landsurface, this small positive flux anomaly is used as heatof fusion to melt the snow pack so 'that the land itselfremains cold longer into the seasonal cycle during theD experiments and hence can be thought of as a heatsink. Since less heat is transmitted to the atmospherethe air

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Jefferson R. Snider, David Leon, and Zhien Wang

of this disagreement is broadening by instruments used to make the spectral measurements ( Cerni 1983 ; Politovich 1993 ; Brenguier and Chaumat 2001 ). Using models, Cooper (1989) and Cooper et al. (2013) demonstrated how true spectral broadening can result when parcels entering cloud base at differing updrafts, resulting in differing N , come into contact and become mixed. This mechanism was investigated in studies of cumulus ( Politovich 1993 ; Hudson et al. 2012 ) and in studies of

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