Modeling the diurnal variability of effective albedo for cities

Sailor, David J.; Fan, Hongli

doi:10.1016/s1352-2310(01)00452-6

Cited by 91 publications

(56 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…At U1, U2, and S1 the large field of view includes different surface materials, and the complex morphometric configuration (orientations, density, height) results in multiple reflections and shading, which all lower the reflectivity of the surface. The albedo measured in the city centre is significantly lower than values applied in numerical models, which are typically of the order of 15 to 20% for residential neighbourhoods (Sailor and Fan, 2002), suggesting that dense European city centres are better absorbers of K ↓ than most North American city surfaces. Comparably low values of ∼8% were recently reported from a dense urban canopy in Lodz, Poland (Offerle et al, 2003a) and from the city centre of Marseilles, France (Lemonsu et al, 2004).…”

Section: Albedomentioning

confidence: 78%

Energy and radiation balance of a central European city

Christen

Vogt

2004

Intl Journal of Climatology

392

297

View full text Add to dashboard Cite

Results from an experimental network of seven energy balance stations in and around a European city are presented. The network of micrometeorological stations was part of the Basel Urban Boundary Layer Experiment (BUBBLE) carried out in the city of Basel, Switzerland. Three urban sites provided turbulent flux densities and radiation data over dense urban surfaces. Together with a suburban site and three rural reference sites, this network allowed the simultaneous comparison of urban, suburban, and rural energy balance partitioning during one month of summertime measurements. The partitioning is analysed together with long-term data to evaluate the magnitude of the urban flux density modification, and to document characteristic values in their diurnal and yearly course. Simple empirical relations between flux densities and surface characteristics are presented. The energy balance partitioning is addressed separately for daytime and nocturnal situations. All four components of the surface radiation budget are analysed. Moreover, the vertical flux density divergences within the urban canopy layer are discussed.

show abstract

Section: Albedomentioning

confidence: 78%

Energy and radiation balance of a central European city

Christen

Vogt

2004

Intl Journal of Climatology

392

297

View full text Add to dashboard Cite

show abstract

“…From Aida (1982Aida ( ). et al 2002Sailor and Fan 2002) or threedimensional arrays of homogeneous buildings Kanda et al 2005a;Kondo et al 2005) without snow cover and vegetation are theoretically predictable using the surface geometry, the albedo of the individual constituent facets, and the solar position. Measured values of albedo in urban areas range from 0.10 to 0.27, with a mean near 0.15 (see Oke 1987, 1988and Arnfield 2003.…”

Section: Urban Surfaces As the Bottommentioning

confidence: 99%

Progress in Urban Meteorology :A Review

Kanda

2007

Journal of the Meteorological Society of Japan

101

View full text Add to dashboard Cite

This paper reviews the progress made in urban meteorology over the past few decades. The focus is on the impact of urban surfaces on the overlying atmosphere along the conventional meteorological frameworks. Section 1 details the difficulties in generalizing urban surfaces in a meteorological sense because of surface diversity, and considers whether conventional similarity law is applicable. Section 2 describes the characteristics of urban surfaces as the bottom boundary of the atmosphere and includes a discussion of land surface parameters and the resultant surface energy partitioning. Section 3 explains characteristics of the urban atmosphere, including temperature fields, local circulations and rainfall. Section 4 describes recent progress in numerical modeling and promising new technologies, thus revealing a possible future direction for urban meteorological studies.

show abstract

“…One question is whether an appointed albedo value can replace the real varying albedo. According to the findings of Sailor and Fan, a typical albedo value may be better than a dynamic albedo [29]. Offerle et al [10] found that the diurnal variation albedo had little effect on net radiation and that it did not significantly improve the model accuracy (RMSE dropped by only 0.6 W/m 2 ).…”

Section: Narp Limitationsmentioning

confidence: 99%

Modeling the radiation balance of different urban underlying surfaces

Cui

Liu

et al. 2012

Chin. Sci. Bull.

View full text Add to dashboard Cite

An urban net all-wave radiation parameterization scheme is evaluated using annual datasets for 2010 recorded at a Beijing urban observation site. The statistical relationship between observed data and simulation data of net radiation has a correlation coefficient of 0.98 and model efficiency of 0.93. Therefore, it can be used to simulate the radiation balance of Beijing. This study analyzes the variation in the radiation balance for different underlying surfaces. To simulate radiation balance differences, we set four pure land-cover types (forest, grass, roads, and buildings). Keeping all other conditions inputted unchanged, we model the radiation balance by changing the land-cover type. The results show that the effects of different underlying surfaces on radiation differ, and that there is much upward long-wave radiation, accounting for 84.3% of the total radiation energy falling incident on the land surface. The annual averages of net radiation for the four land-cover types are in the range of 38.2-53.4 W/m 2 . The net radiation of the grass surface is minimal while that of the roads surface is maximal. Additionally, with urbanization the net radiation values of common types of land-cover change, such as conversion from forest to roads, grass to roads, and grass to buildings, all have increasing trends, indicating that net radiation usually increases with urban sprawl. Land surfaces interact with the atmosphere through the exchange of water, energy and momentum. Any changes in energy flux between the land and atmosphere will affect the atmospheric thermal conditions and atmospheric circulation. The underlying surfaces (land use/land cover classes) greatly affect the climate according to their physical properties, such as the surface albedo, roughness, and emissivity [1]. The components of the radiation balance, the net radiation in particular, are main components of the land surface energy budget and are important physical and ecological parameters in the land-atmosphere energy exchange and redistribution [2]. The relationship between the type of urban underlying surface and the radiation energy budget is a core issue of urban climate. The effect of the urban land surface energy flux on local climate has been verified in many studies [3]. Therefore, systematic analysis of the urban radiation balance of various underlying surfaces is a basis and prerequisite for urban energy balance studies, and it is also important in understanding change processes of urban energy for different underlying surfaces and local climate caused by urban sprawl [4].The basic characteristic of urban landscape is the spatial heterogeneity of its land surfaces, and differences in landscape composition lead to the nonuniformity of energy transmission and distribution. Urban land surface is a complex physical interface. As surface characteristics change, the thermodynamic and kinetic properties of underlying surfaces can substantially change. All these disturbance factors will result in city-specific climatic characteristics. Most previo...

show abstract

Modeling the diurnal variability of effective albedo for cities

Cited by 91 publications

References 14 publications

Energy and radiation balance of a central European city

Energy and radiation balance of a central European city

Progress in Urban Meteorology :A Review

Modeling the radiation balance of different urban underlying surfaces

Contact Info

Product

Resources

About