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Robert E. Tuleya and Yoshio Kurihara

results ofseveral experiments. The relative influence of the depletion of evaporation and of increased surface roughness in the maintenance and decay of a tropical cycloneupon landfall are discussed in particular. Landfall maybe defined, specifically, as the instant of time when thecenter of a tropical cyclone encounters the coastline.More generally, landfall may be considered to be theprocess of the entire storm system moving over land.In this study the first definition is used primarily,although the

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Kathleen A. Schiro and J. David Neelin

deep-inflow assumption to predict deep convective onset across both land and ocean regions in the tropics using TRMM 3B42 precipitation and ERA-Interim moisture and temperature. Here, we extend the analysis of Schiro et al. (2016 , 2018 ) to provide a detailed examination of variability in moisture vertical structure (regionally, diurnally, and seasonally; section 3 ), its relation to convective onset and convective organization ( section 4 ), the effects of moisture on the conditional

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Alexei Lyapustin, D. L. Williams, B. Markham, J. Irons, B. Holben, and Y. Wang

theoretical and simulation studies ( Lyapustin 2001 ) showed that the window size of 2–5 km quite accurately represents the 1D regime over land under a variety of conditions. In this work, we are using the window of 3 km × 3 km, which was additionally adjusted by trial and error based on real Landsat scenes. Also, below, we refer to q and L as locally averaged quantities. The traditional remote sensing of aerosol and land surface reflectance is based on the independent pixel approximation (IPA), that

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J. E. Kutzbach and B. L. Otto-Bliesner

does notinfluence greatly the results for the African-Eurasian'land mass that are emphasized in Section 4 (Section5 compares experiments with and without the NorthAmerican ice sheet). The 9000 years B.P. sea-iceextent is also set at modern values.3. The low-resolution model A low-resolution model of the general circulationof the global atmosphere is used for the experiment(Otto-Bliesner et al., 1982). The model incorporatesatmospheric dynamics based upon the equations ofmotion. The equations are

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Fei Chen, Thomas T. Warner, and Kevin Manning

the specific location and intensity of this event were determined. The purposes of this study are to 1) define the sensitivity of the intensity and position of the convection in this large-scale environment to local and regional landscape variability, and 2) assess the skill with which this convective event in mountainous terrain can be simulated using a convection-resolving model that employs high-resolution terrain and land surface properties. The objectives are both practical as well as

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L. A. Remer, Y. J. Kaufman, D. Tanré, S. Mattoo, D. A. Chu, J. V. Martins, R.-R. Li, C. Ichoku, R. C. Levy, R. G. Kleidman, T. F. Eck, E. Vermote, and B. N. Holben

MODIS cloud mask product identified as MOD/MYD35 ( Ackerman et al. 1998 ) and meteorological data from the National Centers for Environmental Prediction (NCEP) provide the input for the algorithms. The MOD/MYD35 cloud mask product also supplies the earth’s surface information that identifies whether a pixel is a “land” pixel or a “water” pixel. Although the algorithm inputs the NCEP data, it can run successfully without these supplements by using climatology for first-guess water vapor and ozone

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Weixing Shen, Isaac Ginis, and Robert E. Tuleya

. (1984) differentiated the relative roles of surface evaporation cutoff and increased friction for landfalling hurricanes. All the above numerical investigations used fixed underlying surface conditions. However, hurricane interaction with underlying surface results in changes of the underlying surface characteristics, in particular change of the surface evaporation, the primary energy source for hurricanes. Hurricane intensity is thus effected by surface feedback mechanisms both over land and water

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Yu Du, Richard Rotunno, and Qinghong Zhang

1. Introduction Diurnal variation of the boundary layer winds is a prominent feature of coastal regions, where land–sea temperature gradients exist, or near mountains, where slope flows are prevalent ( Rotunno 1983 ; Stensrud 1996 ; Rife et al. 2010 ). A common feature of these winds is a nocturnal low-level jet (LLJ) that frequently occurs in those regions, such as the Great Plains LLJ, east of the Rocky Mountains ( Bonner 1968 ; Whiteman et al. 1997 ), the California coastal jet ( Burk and

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Jie Tang, Jun A. Zhang, Sim D. Aberson, Frank D. Marks, and Xiaotu Lei

). Besides the abovementioned in situ turbulence observations, Lorsolo et al. (2010) presented a novel technique to calculate turbulent kinetic energy (TKE) in hurricanes using Doppler radar measurements. They found that the largest TKE is located in the PBL of hurricane eyewalls. Turbulence observations over land in TCs are as difficult to obtain as those over the ocean because of the severe environment for an instrument and data system to survive. Almost all the previously reported turbulence

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Xingchao Chen, Fuqing Zhang, and Kun Zhao

), ambient wind (e.g., Qian et al. 2009 ), shoreline curvature (e.g., Baker et al. 2001 ), inland terrain (e.g., Qian 2012 ), atmospheric stability (e.g., Walsh 1974 ), land cover (e.g., Zhang et al. 2005 ), land use (e.g., G. Chen et al. 2015 ), and the urban heat island circulation (e.g., Freitas et al. 2007 ) can also dramatically influence the characteristics of the land and sea breeze. In consequence, the land- and sea-breeze circulations often vary markedly from region to region. Diurnal

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