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Sam I. Outcalt

1972 S A M I. O U T C A L T 1369A Reconnaissance Experiment in Mapping and Modeling the Effect of Land Use on Urban Thermal Regimes $A.~r I. OUTCALTDept. of Geography and Willow Run Laboratories,~ The University of Michigan, Ann Arbor 48104(Manuscript received 31 January 1972, in revised form 9 August 1972)ABSTRACT A simple digital climate simulator was modified for

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Nicolas Schneider, Werner Eugster, and Barbara Schichler

1. Introduction In the context of global warming, a better understanding of the effects of land surface changes on the climate has become more and more important in order to be able to separate the impacts of land-use changes on the regional climate from those of global warming. Stohlgren et al. ( Stohlgren et al., 1998 ), for example, concluded that, on a regional scale, larger-scale temperature changes associated with observed increases in greenhouse gases may be dominated by the effects of

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Fatima Karbou, Elisabeth Gérard, and Florence Rabier

regressions and empirical models ( Weng et al. 2001 ; Grody 1988 ) has been used in NWP and has facilitated the assimilation of AMSU channels over land. The effectiveness of these models depends on the input parameters about the surface, for which a global analysis does not always exist. To date, observations are more intensively used over sea than over land thanks to effective sea emissivity models ( Deblonde and English 2000 ; Guillou et al. 1998 ; Prigent and Abba 1990 ; Guissard and Sobieski 1987

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Camille Birman, Fatima Karbou, and Jean-François Mahfouf

precipitation enhances the low background radiances at the top of the atmosphere. Since microwave instruments are only available on board low-orbiting satellites, they suffer from rather poor temporal sampling. Over oceans, microwave observations have been used to detect precipitating events and to retrieve rain products (e.g., Hilburn and Wentz 2008 ; Funatsu et al. 2007 ). Over land surfaces, rainfall retrieval from microwave radiances can only been achieved through the scattering signal produced at

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John R. Mecikalski, George R. Diak, Martha C. Anderson, and John M. Norman

developed by Anderson et al. (1997) that does not suffer from large data requirement and data processing handicaps; only a modicum of supporting data and computer processing time are necessary to make continental-scale flux evaluations. The Atmosphere–Land Exchange Inversion (ALEXI) model has been designed to mitigate many of the problems encountered in earlier land surface flux estimation methods that employ thermal infrared (TIR) measurements of the surface. Using surface temperature measurements

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Omar V. Müller, Ernesto Hugo Berbery, Domingo Alcaraz-Segura, and Michael B. Ek

from land-use and land-cover changes, either from natural or anthropogenic origin or from climate conditions that affect the vegetation health and its phenology. Abundant evidence based on model simulations has been offered on the impacts of land-cover changes on regional to global climate and will not be reviewed here (see, e.g., Pielke et al. 2007 , and references therein; Mahmood et al. 2010 ). The need for a correct representation of the land surface in models has been discussed for many

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Zhong Zhong, Yuan Sun, Xiu-Qun Yang, Weidong Guo, and Haishan Chen

-called effective roughness length , which represents the integrated frictional effect for different land-use categories. Since the 1980s, many estimation schemes for have been proposed ( André and Blondin 1986 ; Kondo and Yamazawa 1986 ; Taylor 1987 ; Mason 1988 ; Vihma and Savijärvi 1991 ; Wood and Mason 1991 ; Schmid and Bünzli 1995 ; Hasager and Jensen 1999 ; Albertson and Parlange 1999 ; Bou-Zeid et al. 2004 , 2007 ; Zeng and Wang 2007 ; Kanda et al. 2007 ; Jiménez and Dudhia 2012 ; Han et

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Nathalie de Noblet-Ducoudré, Juan-Pablo Boisier, Andy Pitman, G. B. Bonan, V. Brovkin, Faye Cruz, C. Delire, V. Gayler, B. J. J. M. van den Hurk, P. J. Lawrence, M. K. van der Molen, C. Müller, C. H. Reick, B. J. Strengers, and A. Voldoire

1. Introduction Land use–land cover change (LULCC) via deforestation, or via conversion of natural grasslands, occurs principally for urbanization and agriculture. It is a process that probably began with human’s systematic use of fire ~400 000 yr ago ( Williams 2003 ). There is no doubt that LULCC has been geographically extensive ( Defries et al. 1995 ; Ramankutty and Foley 1999 ; Klein Goldewijk 2001 ; Hurtt et al. 2006 ; Pongratz et al. 2008 ; Klein Goldewijk et al. 2011 ; Kaplan et

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Yongkang Xue, Heidi G. Bastable, Paul A. Dirmeyer, and Piers J. Sellers

386 JOURNAL OF APPLIED METEOROLOGY VOLUME35Sensitivity of Simulated Surface Fluxes to Changes in Land Surface Parameterizationsm A Study Using ABRACOS Da/aYONGKANO XUECenter for Ocean-Land-Atmosphere Studies, Calverton, Maryland HEIDI G. BASTABLEInstitute of Hydrology, Wallingfon~ United Kingdom PAUL A. DIRMEYERCenter for Ocean-Land-Atmosphere Studies

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J. A. Wang, L. R. Hutyra, D. Li, and M. A. Friedl

across cities ( Schatz and Kucharik 2014 ). Studies of the UHI typically use point measurements of near-surface air temperature T a or satelliteborne thermal remote sensing to characterize the nature and magnitude of urban–rural temperature differences. In this paper, we refer to UHI specifically in reference to elevated air temperature associated with urban land use, in contrast to the surface urban heat island (SUHI), which represents elevated urban land surface temperature. Remote sensing

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