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Lorenzo Giovannini, Dino Zardi, and Massimiliano de Franceschi

1. Introduction Urban areas are known to display different climatic conditions than the surrounding countryside, primarily associated with the so-called urban heat island (UHI), that is, with higher values of surface air temperature occurring in the city center than in surrounding rural areas. The UHI effect is mainly due to the strong modifications produced in the surface energy budget by urban surfaces covered with artificial materials (buildings, paved roads, etc.). However, another

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Fang Wang, Quansheng Ge, Shaowu Wang, Qingxiang Li, and Philip D. Jones

Report mentioned, most recent attention on urban heat island (UHI) effects has focused upon China ( Hartmann et al. 2013 ). Some studies have indicated that the UHI contribution was large, while some have showed a smaller contribution ( Table 1 ). Some studies looked at individual sites and estimated the UHI effects based on cities of different sizes. For example, Chu and Ren (2005) estimated an urbanization contribution to Beijing’s temperature change to be 71% during 1961–2000 and 49% during 1979

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Juan Declet-Barreto, Kim Knowlton, G. Darrel Jenerette, and Alexander Buyantuev

1. Introduction Exposure to high summertime temperatures is a significant threat to human health, especially in cities, where urban heat islands (UHIs) are elevating temperatures already on the rise from global climate change. Heat-retaining, impervious land covers like paved roadways and unvegetated surfaces and alterations to wind and energetic flows from vertical surfaces of buildings elevate local temperatures in UHIs. These anthropogenic, regional-scale transformations to natural land

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Thomas C. Peterson and Timothy W. Owen

1. Introduction Understanding urban heat island (UHI) contamination in the in situ climate record is a complex task because the results are impacted by a wide variety of factors not related to urbanization. For example, temperature observations are impacted by differing observing times, different instrumentation, and different siting practices, each of which may cause inhomogeneities in space when comparing values from several different stations in and around a town and discontinuities in time

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R. A. Preston-Whyte

AUGUST1970 R. A. PRESTON-WHYTE 571A Spatial Model of an Urban Heat IslandR. A. PRESToN-WItyTEDept. of Geography, University of Natal, Durban, South Africa (Manuscript received 11 March 1970)ABSTRACT Mean temperatures obtained from 28 midday motor traverses in the Durban area during the summerof 1968-69 show the center of the heat island to be displaced away from the central business

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Shaoxiu Ma, Andy Pitman, Jiachuan Yang, Claire Carouge, Jason P. Evans, Melissa Hart, and Donna Green

; Zander et al. 2015 ). The risk of heat stress on urban residents is increasing in some regions because of urbanization, the urban heat island (UHI) effect ( Fischer et al. 2012 ; Oleson et al. 2015 ), and global warming ( Sherwood and Huber 2010 ; Zhao et al. 2015 ). While it is possible that some cities are seeing a decline in heat-related mortality ( Barnett 2007 ; Carson et al. 2006 ; Davis et al. 2003 ; Sheridan et al. 2009 ), the overall trend is toward increasing heat stress on humans

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Humberto R. Silva, Rahul Bhardwaj, Patrick E. Phelan, Jay S. Golden, and Susanne Grossman-Clarke

. In turn, these engineered changes in land surface and supporting urban systems impact the partitioning of surface energy ( Taha 1997 ). This impact is often manifested in micro- and mesoscale modifications to the thermal properties of the surface and atmosphere and can result in rapid change in the urban climate in comparison with adjacent rural regions, known as the urban heat island (UHI) effect (see, e.g., Oke 1987 ; Grimmond 2006 ). Contributions of engineered materials to urban climatology

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Jong-Jin Baik, Yeon-Hee Kim, and Hye-Yeong Chun

meteorological data in the Atlanta area. Their analysis of six precipitation events over the city for nine summer days revealed that the urban heat island induced a convergence zone that initiated three of the convective thunderstorms at different times of the day. A critical review of urban effects on precipitation amount is given by Lowry (1998) . These and other observational studies confirm that cities can initiate convection, split convective storms, change the behavior of convective precipitation, and

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Yeon-Hee Kim and Jong-Jin Baik

Introduction In most big cities, urbanization has produced significant changes in the surface and atmospheric properties that can subsequently result in inadvertent local weather and climate changes ( Changnon 1981 ; Cotton and Pielke 1995 ). The urban heat island (UHI) phenomenon, in which surface air temperature in an urban area is higher than in the surrounding suburbs and rural area, is a feature commonly observed in many cities, and its characteristics have been extensively studied

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Hannu Savijärvi and Stuart Matthews

and Grubiac 1993 ; Reisner and Smolarkiewicz 1994 ) primarily act as mechanical obstacles on the flow. The circulations associated with small islands (5–40 km in diameter) are perhaps the least well known. Studies of these are briefly summarized in section 2 . We have traced two types of linear analytic models for heat islands. The first is for oscillating land and sea breezes (SBs) with no large-scale wind, such as Defant's (1950 ; see also Pielke 2002 ). The second is for steady- state flow

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