Abstract
Heat island effects and their thermal impacts have become a key consideration in the environment of tropical cities. In the face of such conditions, the land use planning and conservation authority of Singapore currently has an on-going island-wide study and plans to manage urban heat at the macro level, but there have been few considerations for the actual thermal environment within these spaces. In tropical climates, solar radiation is the greatest source of heat, and mitigation of solar and terrestrial radiation by landscape design is of utmost importance as compared to other microclimatic factors.
Vegetation and trees in particular have been found to not only intercept direct short-wave solar radiation, but also to reduce reflected short-wave radiation as well as terrestrial radiation in the outdoor environment, through filtering light and radiation with their canopies and providing shade. The micro-scale thermal influence of selected trees was studied during the daytime, comparing characteristics of trees by assessing operative temperature and levels of light infiltration. It was found that canopy density of trees, which determines density of shade, correlates with thermal performance; a tree with a dense canopy can reduce operative temperatures up to 6.3 °C; second, thermal performances ranged widely between surveyed trees. For instance, larger trees remain the most consistent performer throughout the day, even during the hottest time period (12–2 p.m.), where a cool point could be noted. Third, park layouts surveyed demonstrate the critical thermal points of paved area, shaded area, and sun direction.
The thermal performance and cooling function of urban green spaces has known effects in ameliorating not only the spaces themselves but the neighbouring urban blocks too. Studies and findings of this kind have the potential to inform design guidelines and practices, of broad relevance for parks, green belts and other urban spaces, in order to achieve better outdoor environments as well as improved urban microclimates, hence in turn reducing the cooling needs of tropical cities. Whilst the specific design features may be somewhat different, such strategies are equally important for the cities in the hot-dry climates.
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References
Akbari, H. (1992). Cooling our communities: A guidebook on tree planting and light-colored surfacing. Berkeley: Lawrence Berkeley Laboratory.
Balogun, A. A., Morakinyo, T. E., & Adegun, O. B. (2014). Effect of tree-shading on energy demand of two similar buildings. Energy and Buildings, 81, 305–315. https://doi.org/10.1016/j.enbuild.2014.05.046
Bowler, D. E., Buyung-Ali, L., Knight, T. M., & Pullin, A. S. (2010). Urban greening to cool towns and cities: A systematic review of the empirical evidence. Landscape and Urban Planning, 97(3), 147–155. https://doi.org/10.1016/j.landurbplan.2010.05.006
Brown, R. D., & Gillespie, T. J. (1995). Microclimatic landscape design: Creating thermal comfort and energy efficiency. New York: Wiley.
Chen, Y., & Wong, N. H. (2006). Thermal benefits of city parks. Energy and Buildings, 38(2), 105–120. https://doi.org/10.1016/j.enbuild.2005.04.003
Emmanuel, R. (2005). An urban approach to climate-sensitive design: Strategies for the tropics. New York: Spon Press.
Erell, E., Pearlmutter, D., & Williamson, T. (2011). Urban microclimate: Designing the spaces between buildings. London: Earthscan.
Fanger, P. O. (1972). Thermal Comfort. Düisseldorf/New York/London: McGraw Hill Book Company.
Fong, M., & Ng, L. K. (2012). The weather and climate of Singapore (2nd ed.). Singapore: Meteorological Service Singapore.
Hwang, Y. H., & Tan, Y. C. (2013). A study on greenery factors for cooler park connectors in Singapore. The International Journal of the Constructed Environment, 3(1), 1–13.
Hwang, Y. H., Lum, Q. J. G., & Chan, Y. K. D. (2015). Micro-scale thermal performance of tropical urban parks in Singapore. Building and Environment, 94, 467–476. https://doi.org/10.1016/j.buildenv.2015.10.003
International Organization for Standardization. (1994). ISO 7730:1994 Moderate thermal environments: Determination of the PMV and PPD indices and specification of the conditions for thermal comfort. Geneva: ISO.
ISO, I. (1998). 7726, Ergonomics of the thermal environment, instruments for measuring physical quantities. Geneva: International Standard Organization.
Jendritzky, G., & Nübler, W. (1981). A model analysing the urban thermal environment in physiologically significant terms. Meteorology and Atmospheric Physics, 29, 313–326.
Kotzen, B. (2003). An investigation of shade under six different tree species of the Negev desert towards their potential use for enhancing micro-climatic conditions in landscape architectural development. Journal of Arid Environments, 55(2), 231–274. https://doi.org/10.1016/s0140-1963(03)00030-2
Mahmoud, A. H. A. (2011). Analysis of the microclimatic and human comfort conditions in an urban park in hot and arid regions. Building and Environment, 46(12), 2641–2656. https://doi.org/10.1016/j.buildenv.2011.06.025
Mayer, H., & Hoppe, P. (1987). Thermal comfort of man in different thermal environments. Theoretical and Applied Climatology, 38, 43–49.
Ministry of National Development. (2013). Population white paper: A sustainable population for a dynamic Singapore. Retrieved from Singapore http://www.ura.gov.sg/uol/publications/research-resources/plans-reports/Concept%20Plan%202011/land_use_plan_2013.aspx
Monteith, J. L. (1981). Evaporation and surface temperature. Quarterly Journal of the Royal Meteorological Society, 107(451), 1–27.
Müller, N., Kuttler, W., & Barlag, A.-B. (2014). Counteracting urban climate change: Adaptation measures and their effect on thermal comfort. Theoretical and Applied Climatology, 115(1), 243–257. https://doi.org/10.1007/s00704-013-0890-4
National Environment Agency. (2015a). Daily values of meteorological elements in 2014. Singapore: National Environmental Agency. Retrieved from http://www.nea.gov.sg/weather-climate/climate-information/weather-statistics
National Environment Agency. (2015b). Local climatology. Retrieved June 10, 2014, from http://www.nea.gov.sg/weather-climate/climate-information
Nieuwolt, S. (1966). The urban microclimate of Singapore. The Journal of Tropical Geography, 22, 30–37.
Roth, M., & Chow, W. T. L. (2012). A historical review and assessment of urban heat island research in Singapore. Singapore Journal of Tropical Geography, 33(3), 381–397. https://doi.org/10.1111/Sjtg.12003
Shahidan, M. F., Shariff, M. K. M., Jones, P., Salleh, E., & Abdullah, A. M. (2010). A comparison of Mesua Ferrea L. and Hura Crepitans L. for shade creation and radiation modification in improving thermal comfort. Landscape and Urban Planning, 97(3), 168–181. https://doi.org/10.1016/j.landurbplan.2010.05.008
Shashua-Bar, L., & Hoffman, M. E. (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 and Buildings, 31(3), 221–235.
Shashua-Bar, L., Tsiros, I. X., & Hoffman, M. E. (2010). A modeling study for evaluating passive cooling scenarios in urban streets with trees. Case study: Athens, Greece. Building and Environment, 45(12), 2798–2807. https://doi.org/10.1016/j.buildenv.2010.06.008
Tan, C. L., Wong, N. H., & Jusuf, S. K. (2013). Outdoor mean radiant temperature estimation in the tropical urban environment. Building and Environment, 64, 118–129. https://doi.org/10.1016/j.buildenv.2013.03.012
Thorsson, S., Lindqvist, M., & Lindqvist, S. (2004). Thermal bioclimatic conditions and patterns of behaviour in an urban park in Goteborg, Sweden. International Journal of Biometeorology, 48(3), 149.
Urban Redevelopment Authority. (2012). Designing our city: Planning for a sustainable Singapore. In skyline [Supplement]. Singapore: Urban Redevelopment Authority.
Wong, N. H., & Jusuf, S. K. (2010). Study on the microclimate condition along a green pedestrian canyon in Singapore. Architectural Science Review, 53(2), 196–212. https://doi.org/10.3763/asre.2009.0029
Wong, N. H., Chen, Y., Ong, C. L., & Sia, A. (2002). Investigation of thermal benefits of rooftop garden in the tropical environment. Building and Environment, 38, 261–270.
Yang, W., Wong, N. H., & Jusuf, S. K. (2013). Thermal comfort in outdoor urban spaces in Singapore. Building and Environment, 59, 426–435.
Yee, A. T. K., Corlett, R. T., Liew, S. C., & Tan, H. T. W. (2011). The vegetation of Singapore – An updated map. Gardens’ Bulletin Singapore, 63(1&2), 205–212.
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Hwang, Y.H., Lum, Q.J.G., Lim, L.X.C. (2018). Cooling with Green Infrastructures: The Influence of Trees on Thermal Conditions in Tropical Urban Parks. In: Cheshmehzangi, A., Butters, C. (eds) Designing Cooler Cities. Palgrave Series in Asia and Pacific Studies. Palgrave Macmillan, Singapore. https://doi.org/10.1007/978-981-10-6638-2_6
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DOI: https://doi.org/10.1007/978-981-10-6638-2_6
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