Abstract
Study intent Greenery in a high-rise urban environment provides accessible amenity space and moderated microclimate for the local community. At the urban-to-local scale, urban greenery contributes to heat island mitigation; at the microscale, landscape elements moderate pedestrian-level thermal comfort; and at the building scale, nearby trees and facade greening or, vertical greening system (VGS), mediate building heat gain and improve indoor comfort and indoor energy performance without occupying valuable urban land. This chapter synthesizes a series of case-based investigations on the thermal environmental performance of urban greenery at three scales. The first case attempted to understand the local urban effects on the cooling performance of greenery under a simplified LCZ scheme. The second case compared two housing block design strategies to reduce summertime heat gain in outdoor space, i.e., high-albedo pavement and vegetation, particularly trees, through field measurement and numerical simulation. The third case experimentally studied the energy and thermal performance of a double-skin green façade system on an office building. Results and discussion The local urban density and land cover properties have notable effect on the microscale cooling rates of greenery. Tree canopy shading and overall foliage density, qualified by the tree view factor and green plot ratio, respectively, were capable of partly explaining the variation in air temperature reduction. To optimize cooling performance, residential greenery should be integrated into the local green network system. Regarding the two strategies, i.e., albedo and greenery, the second case study reveals that increasing greenery cover, especially tree cover, improves thermal comfort from mid-day till early night. In contrast, increasing ground surface albedo overall worsens the thermal comfort during the day with a marginal benefit at night. At the building scale, the experiment reveals that the double-skin green facades on both south and north façade create a distinctive microclimate in the cavity. The exterior wall surface temperature reduction of the southern facade reached maximally 9 ℃, whereas the interior surface reduced maximally 2 ℃. The resultant indoor thermal and energy improvements by the VGS were evaluated accordingly.
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsReferences
Ali-Toudert F (2005) Dependence of outdoor thermal comfort on street design in hot and dry climate. Meteorological Institute. Feiburg, Freiburg University.
Bowler DE, Buyung-Ali L, Knight TM, Pullin AS (2010) Urban greening to cool towns and cities: A systematic review of the empirical evidence. Landscape Urban Plann 97:147–155
Bruse M, Fleer H (1998) Simulating surface-plant–air interactions inside urban environments with a three dimensional numerical model. Environ Model Softw 13:373–384
Che S, Song Y (2001) Extract of the remote sensing message of urban green space landscape—Shanghai city as the Case Study (in Chinese). Urban Environ Urban Ecol 14:10–12
Eumorfopoulou EA, Kontoleon KJ (2009) Experimental approach to the contribution of plant-covered walls to the thermal behaviour of building envelopes. Build Environ 44:1024–1038
Gao K, Qin J, Song K, Hu Y (2009) Fallen temperature effects at green patches of urban residential areas and analysis of its influence factors. J Plant Resour Environ 18:50–55 (in Chinese, with English summary)
Hoppe P (1999) The physiological equivalent temperature—A universal index for the biometeorological assessment of the thermal environment. Int J Biometeorol 43:71–75
Lee LSH, Jim CY (2017) Subtropical summer thermal effects of wirerope climber green walls with different air-gap depths. Build Environ 126:1–12
Oke TR, Crowther JM, McNaughton KG, Monteith JL, Gardiner B (1989) The micrometeorology of the urban forest. Philos Trans R Soc London Ser B Biol Sci 324:335–349
Perini K, Bazzocchi F, Croci L, Magliocco A, Cattaneo E (2017) The use of vertical greening systems to reduce the energy demand for air conditioning. field monitoring in Mediterranean climate. Energy Build 143:35–42
Shashua-Bar L, Hoffman M (2000) Vegetation as a climatic component in the design of an urban street: an empirical model for predicting the cooling effect of urban green areas with trees. Energy Build 31:221–235
Yang F, Lau SSY, Qian F (2010) Summertime heat island intensities in three high-rise housing quarters in inner-city Shanghai China: Building layout, density and greenery. Build Environ 45:115–134
Yang F, Yuan F, Qian F, Zhuang Z, Yao J (2018) Thermal and energy performance of a double-skin green facade: A case study in Shanghai. sustainable cities and society 39:43–51. https://doi.org/10.1016/j.scs.2018.01.049
Yang F, Lau S, Qian F (2015) Cooling performance of residential greenery in localised urban climates: A case study in Shanghai China. Inter J Environ Technol Manag 18(5/6):478–503
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
Copyright information
© 2020 Springer Nature Singapore Pte Ltd.
About this chapter
Cite this chapter
Yang, F., Chen, L. (2020). Cooling Effects of Urban Greenery at Three Scales. In: High-Rise Urban Form and Microclimate. The Urban Book Series. Springer, Singapore. https://doi.org/10.1007/978-981-15-1714-3_7
Download citation
DOI: https://doi.org/10.1007/978-981-15-1714-3_7
Published:
Publisher Name: Springer, Singapore
Print ISBN: 978-981-15-1713-6
Online ISBN: 978-981-15-1714-3
eBook Packages: Earth and Environmental ScienceEarth and Environmental Science (R0)