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N. Cubukcu, R. L. Pfeffer, and D. E. Dietrich

and Ginis (1991) , who also studied the effect of the ocean–air interaction on the path of the hurricane. More recently, Bender et al. (1993) found that the ocean response was quicker by about 12 h when they employed a numerical model with higher resolution than the ones used in the earlier studies. Among the aforementioned studies, the only ones dealing with the effect of bottom topography or land–sea contrasts were those by Cooper and Thompson, Tuleya et al., and Tuleya. Cooper and Thompson

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F. J. Robinson, S. C. Sherwood, D. Gerstle, C. Liu, and D. J. Kirshbaum

and land. The solid lines are 2D WRF simulations for the six different soundings (HIRH: green, LOWRH: dark blue, HS01: pink, LS01: orange, HS06: light blue, and HS06: red) vs island area, using (a) Morrison or (b) Thompson microphysics. Fig . 9. Minimum (a) 85-GHz and (b) 37-GHz PCT, and (c) maximum 40-dB Z height vs island/heating area. Here results are averaged over the six initial soundings for the models, and over octaves of island size for the observations. Model means are shown separately

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Zachary R. Hansen, Larissa E. Back, and Peigen Zhou

surface temperature (and heating) over land as compared to over the ocean. We do this through the use of cloud-permitting model (CPM) island simulations, satellite data, and reanalysis data. We show that while the diurnal cycle affects quantities and distributions of large-scale precipitation, it does not impact high-intensity updraft velocity statistics in the CPM simulations, after controlling for large-scale precipitation variations. In contrast, the land–ocean lightning difference in nature

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Yun Lin, Jiwen Fan, Jong-Hoon Jeong, Yuwei Zhang, Cameron R. Homeyer, and Jingyu Wang

1. Introduction Urbanization is an extreme case of land-use change ( Shepherd 2005 ), along with intensive anthropogenic aerosol emissions. Worldwide urban land and population have grown rapidly over the twentieth century. All regions are expected to urbanize further during the coming decades ( Alig et al. 2004 ). In the United States, urban land is projected to increase from 39.5 million ha in 1997 to 70.5 million ha in 2025 ( Alig et al. 2004 ). Urbanization has significant local impacts on

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Denise Stephenson-Graves

Sellers, 1974).The models used by several of these authors approximate the global climate based upon a zonallydefined area grid which longitudinally accounts forthe proportion of land and water in a given zone. Inthis study, a comparison is made between a linearparameterization of emitted longwave (LW) radiation that is currently used in several EBCM and asatellite data representation of the same radiationbudget variable. The LW radiation data used in thisstudy were derived from measurements

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Kenneth R. Knapp and Larry L. Stowe

index (NDVI) and albedo. The NDVI was developed using the AVHRR and has been used by many to characterize the global land cover (e.g., DeFries and Townshend 1994 ). It has also been linked to vegetation characteristics such as leaf area index ( Schuessel et al. 1994 ). Studies have investigated methods to correct the NDVI and other surface features for the atmospheric effects of gaseous absorption and aerosol extinction (e.g., Rahman and Dedieu 1994 ; Mitchell and O'Brien 1993 ; Justice et al

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Shigeki Mitsumoto, Hiromasa Ueda, and Hiroyuki Ozoe

numerical ex periments, It has been confirmed that these numericalmodels can simulate the general features of the LSB,and so they are being used for atmospheric simulationfor actual regions (Anthes and Warner, 1978; Kikuchiet al., 1981). On the other hand, many field observations oflandand sea (or lake) breeze have been carried out, amongwhich the observations at Lake Michigan (Lyons andOlsson, 1973; Keen and Lyons, 1978) illustrate theactual land and sea/lake breeze as a mesoscale phe'nomenon. These

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Kelly Schrieber, Roland Stull, and Qing Zhang

) of 1986. The full flight track duringHAPEX overflew a wide range of land use including evergreen forest, corn, vineyards, pastures, and irrigatedfields over varied topography. The JFDs from these full tracks are found to be quite complex, being frequentlymultimodal with a convoluted perimeter. However, when a full track is broken into segments, each over asubdomain of quasi-homogeneous land use, the resulting segment JFDs are mono-modal with simpler Wpoloy. Such a characterization of ~FDs

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Shiyuan Zhong and J. C. Doran

boundary layer toinhomogeneous surface fluxes. The study was used to extend the results obtained from a field experiment carriedout in spring 1992 in north-central Oregon over a region characterized by warm, dry sagebrush and grasslandsteppe and cooler, irrigated farmland. Characteristic scales of the two prominent land-use types were on theorder of 10 km or more. A series of numerical experiments were carded out to analyze boundary-layer behavioron three days selected for detailed study, to perform a

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Chiel C. van Heerwaarden and Jordi Vilà Guerau de Arellano

cloud formation are sensitive to heterogeneous forcings at the land surface, which depend on the spatial variability of land use, soil moisture content, and topography. Heterogeneous forcings occur over a wide range of scale levels, but the strongest effects on ABL properties are found when the heterogeneities are in the meso- γ scale (2–20 km) ( Mahrt 2000 ) because they modify the horizontal and vertical structure of the ABL by inducing circulations. A consequence is that the effects of

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