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Yongqiang Liu and Roni Avissar

China. They also found that soil moisture has a much stronger persistence than soil temperature. Two types of mechanism contribute to persistence in the land–atmosphere system: (i) external forcings, including the atmospheric dynamics that produce global circulation systems and control precipitation and cloudiness; and (ii) internal forcings, which consist of self-feedbacks and interactions within the system. Considering that GCMs need very large computing resources and account for a large number of

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M. B. Ek and A. A. M. Holtslag

Schemes (PILPS; e.g., T. H. Chen et al. 1997 ; Wood et al. 1998 ; Chang et al. 1999 ); the study by Chang et al. (1999) includes a comprehensive description of the current physics in the CAPS model land surface scheme. In addition, a number of studies have specifically examined land–atmosphere interactions using the CAPS model in a coupled land surface–ABL column mode (e.g., Ek and Mahrt 1994 ; Ek and Cuenca 1994 ; Xinmei and Lyons 1995 ; Cuenca et al. 1996 ; Holtslag and Ek 1996 ). In this

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Shinjiro Kanae, Yukiko Hirabayashi, Tomohito Yamada, and Taikan Oki

. Lett , 29 . 1746, doi:10.1029/2002GL015346 . Koster , R. D. , M. J. Suarez , and M. Heiser , 2000 : Variance and predictability of precipitation at seasonal to interannual timescales. J. Hydrometeor , 1 , 26 – 46 . Koster , R. D. , P. A. Dirmeyer , A. N. Hahmann , R. Ipelaar , L. Tyahla , P. Cox , and M. J. Suarez , 2002 : Comparing the degree of land–atmosphere interaction in four atmospheric general circulation models. J. Hydrometeor , 3 , 363 – 375 . Koster

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Joseph A. Santanello Jr., Christa D. Peters-Lidard, Sujay V. Kumar, Charles Alonge, and Wei-Kuo Tao

1. Introduction Land–atmosphere (L–A) interactions and coupling remain weak links in current observational and modeling approaches to understanding and predicting the earth–atmosphere system. The degree to which the land affects the atmosphere (and vice versa) is difficult to quantify, given the disparate resolutions and complexities of land surface and atmospheric models and the lack of comprehensive observations at the process level ( Betts et al. 1996 ; Angevine 1999 ; Entekhabi et al

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Jianjun Ge, Nathan Torbick, and Jiaguo Qi

Introduction By changing the fluxes of mass and energy between ecosystems and the atmosphere, human modification of the land surface impacts regional and global climate processes ( Pielke et al. 2002 ; Foley et al. 2003 ). Using land–climate modeling techniques, impacts of land-use and land-cover changes on the Earth system can be studied and monitored. Most regional and global atmospheric models developed 20 years ago either ignored or oversimplified the interactions of the atmosphere with

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Paul A. Dirmeyer and Subhadeep Halder

community experiment to understand land–atmosphere coupling processes. GEWEX News , Vol. 23, No. 2, International GEWEX Project Office, Silver Spring, MD, 3–5 . Betts, A. K. , 2009 : Land-surface–atmosphere coupling in observations and models . J. Adv. Model. Earth Syst. , 1 , doi: 10.3894/JAMES.2009.1.4 . Betts, A. K. , Ball J. H. , Beljaars A. C. M. , Miller M. J. , and Viterbo P. A. , 1996 : The land surface–atmosphere interaction: A review based on observational and global modeling

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Marcus Breil and Gerd Schädler

1. Introduction In regional climate models (RCMs) dynamical processes in the atmosphere are described by partial differential equations that are discretized on a numerical grid. However, physical processes evolving on small spatial and temporal scales, such as the land–atmosphere interaction or convection, are not resolved on that grid scale. For this reason, physical parameterizations are used to calculate these subgrid-scale processes and to supply them as quantities that can be used in the

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R. David Baker, Barry H. Lynn, Aaron Boone, Wei-Kuo Tao, and Joanne Simpson

-breeze-initiated precipitation over the Florida peninsula: soil moisture availability, coastline curvature, and early morning land-breeze circulations. Soil moisture may affect convective development by enhancing atmospheric moisture or by modulating the surface temperature to produce mesoscale circulations. Through strong evapotranspiration, wet soil may act as a moisture source for the overlying atmospheric boundary layer, thus increasing the moist static energy of the atmosphere and promoting convective development (e

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M. A. Friedl

concluded that the estimation of surface fluxes at high spatialresolution is problematic because the remotely sensed measurements reflect local land surface conditions, whileland surface fluxes are produced by processes associated with surface-atmosphere interactions occurring oversubstantially larger areas. Because land surface-atmosphere interactions effectively integrate high-frequencyspatial variance in land surface properties, relatively coarse spatial resolution (hundreds of meters to I kin

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Yongkang Xue, Fernando De Sales, Ratko Vasic, C. Roberto Mechoso, Akio Arakawa, and Stephen Prince

. The UCLA AGCM is a state-of-the-art gridpoint model of the global atmosphere extending from the earth’s surface to the top of 1 hPa. The prognostic variables of this AGCM are the horizontal wind, potential temperature, water vapor mixing ratio, cloud liquid water and cloud ice water, planetary boundary layer (PBL) depth, surface pressure, and land surface temperature. Parameterization of the cumulus convection and its interaction with the PBL follows Pan and Randall (1998) . The geographical

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