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Yu Du and Richard Rotunno

; Wood et al. 2009 ; Rahn and Garreaud 2010 ). Using the Cloud Archive User Service (CLAUS) dataset of brightness temperature, Yang and Slingo (2001) found that a strong diurnal signal (convective activity) over land is spread out over the adjacent sea in the tropics probably through gravity waves. The offshore propagation of diurnal wind variation is significant equatorward of 30° latitude ( Gille et al. 2005 ). Mapes et al. (2003) found that a propagation signal (convection) in the Panama

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Ralph R. Ferraro, Eric A. Smith, Wesley Berg, and George J. Huffman

extremely difficult. Hence, most models simulating land surface signatures havebeen based upon those conditions observed from surface-based radiometers or low-flying aircraft measurements (i.e., Wigneron et al. 1993 ; Schmugge 1983 ), both of which are at much higher spatial resolution and not applicable to satellite retrievals. Ferraro et al. (1986) used Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR) measurements at 19 and 37 GHz to classify surface type from passive microwave

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Xingchao Chen, Fuqing Zhang, and Kun Zhao

. (2012) further examines the effect of coastal topography on tropical land–sea-breeze circulations under different environmental mean flow conditions. Using long-term TRMM observations, Sobel et al. (2011) found that diurnal cycles of precipitation over small islands are stronger over the Maritime Continent where the ambient wind is weak than over the Caribbean where the ambient wind is strong. Through idealized simulations, Wang and Sobel (2017) further demonstrate that the large-scale wind

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Kerry H. Cook

from axisymmetric models. Noting that the tropical heating has pronounced longitudinal structure closely tied to the land–sea distribution, this paper compares the physics of the Hadley circulation in the presence and absence of continents. A fully nonlinear general circulation model (GCM) is used, and so baroclinic instability and feedbacks between the atmospheric dynamics and diabatic heating fields are included and land surface temperature responds to the balance of radiative, sensible, and

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Wen-Yih Sun and Isidoro Orlanski

. iagram, with upward motion on the warm side(i.e.; land) of the coast and downward motion onthe cold side (i.e., ocean). The amplitude of the upward motion is the same as that of the downwardAuausx 1981 WEN-YIH SUN AND ISIDORO ORLANSKI i681motion, because the same temperature stratification N~(z, t) is used for both sides. During the night,ascending motion occurs over the

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Barry H. Lynn and Wei-Kuo Tao

) specific humidity, including moist processes. 4. Summary and conclusions A set of relatively high-resolution three-dimensional simulations were produced to investigate the triggering of moist convection over heterogeneous, west-to-east land surface domains. This moist convection was triggered by mesoscale circulations generated by the landscape heterogeneity. We used a Fourier transform to filter the data, and obtain a distribution of mesoscale and turbulent perturbations. These fluctuations were

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Clark Weaver, Arlindo da Silva, Mian Chin, Paul Ginoux, Oleg Dubovik, Dave Flittner, Aahmad Zia, Lorraine Remer, Brent Holben, and Watson Gregg

.87 μ m, we chose a low error covariance value for this channel. Likewise the radiance at the 0.47- μ m channel is given the largest error because the radiance here may be influenced by chlorophyll absorption. We should clarify that the actual radiance values at 0.47 and 0.87 μ m are equally accurate, but that the 0.47 μ m has less useful aerosol information. Over land there are level-2 radiances only for four channels: 0.47, 0.66, 0.87, and 2.13 μ m. However, we are effectively using information

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Patrick C. Taylor

1 describes the magnitude of the variability in the OLR DC , LWCF DC , α DC , and α cld,DC using simple diurnal cycle metrics: namely, diurnal range and local time of the maximum value ( Slingo et al. 2004 ). In terms of diurnal range, the absolute magnitude of the variability is largest over land; however, percentage variability—relative to the mean diurnal range—is significant and exceeds 20% over ocean. The variability in the local time of the maximum value is quantified by considering

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Zhongfeng Xu, Congbin Fu, and Yongfu Qian

changes. In addition, the land surface condition, such as soil, vegetation, and snow, also affects the magnitude of monsoons ( Tzeng and Lee 2001 ; Qian et al. 2003 ; Wu and Qian 2003 ; Xue et al. 2004 ). Yasunari et al. (2006) evaluated the relative roles of the Tibetan Plateau and continental-scale land surface processes (including soil and vegetation) in the Asian monsoon by using an AGCM. Their results showed that the land surface and Tibetan Plateau effects contribute nearly equally to

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Jielun Sun and Jeffrey R. French

et al. 2012 ). b. HOST hypothesis Recently, limitation of MOST was investigated in the atmospheric boundary layer (ABL) over land by Sun et al. (2012 , 2015 , 2016) using observations from a 60-m tower. They found that atmospheric turbulence consists of large coherent eddies that scale with the distance between the observation height and the surface under strong wind conditions, and those large coherent eddies dominate turbulent mixing and cannot be properly described by MOST. As a result

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