Effect of vegetation and waterbody on the garden city concept: An evaluation study using a newly developed city, Putrajaya, Malaysia
Section snippets
Introduction and background information
At present, approximately 3.9 billion of the world population live in urban areas, which is expected to increase rapidly (United Nations, 2014). This could be due to the rapid rural-to-urban migration of people in developing countries (e.g. China, Brazil, India, Indonesia, Nigeria and Mexico). Urban areas occupy < 3% of the Earth surface (Liu et al., 2014) and the increase in the population of urban residents has exacerbated problems (e.g. waste management, increase in energy consumption,
Study area
Putrajaya is located in the Klang Valley region in Southeast Asia at 2°55′00″ N 101°40′00″ E and 25 km south of Kuala Lumpur (Fig. 1) with an approximate area of 49 km2 previously covered by vegetation, that is, rubber and oil palm plantation. To the east, PC is bordered by Bangi, Cyberjaya to the west and Dengkil to the north. Located few degrees north of the equator with an average elevation of 30 m, PC is a typical tropical city. Rainfall averages 2–3 m per year and falls heavily during the
Methodology and model evaluation
In order to assess the performance of the GCC in mitigating the effect of thermal positive feedback (such as UHI) on the urban and surrounding environment induced by urbanisation, a control case (case 1), two different experiments (cases 2 and 3) and an ideal case (non-urban) were successively simulated. Case 1 represents up-to-date ground truth of the city, while cases 2 and 3 represent scenarios with waterbody and vegetation of PC replaced with high-intensity residential urban surfaces,
Results and discussions
Model results and analyses are conducted for d03 only, except otherwise stated. Presented results are averaged over 513 grid cells (Fig. 3a) within PC for a 24-h temporal scale. Fig. 4a shows a graphical representation of reclassified land use and land cover for the three scenarios investigated. Vegetated land use classes were reclassified to greenery, while urban classes were reclassified to urban. Waterbodies and sparsely vegetated regions are left as originally classified. It is worth noting
Conclusions
Coupled WRF/Noah/UCM was used to simulate the urban environment of Putrajaya using a one-way downscaling approach to investigate the effectiveness of the GCC adopted during the development of PC. Simulated results compared well with observational data. Surface energy balance analysis indicates that direct solar radiation predominates urban exchange of momentum, heat and water vapour during daytime. However, exchange of fluxes during night and early hours was controlled by reradiated absorbed
Acknowledgements
The authors would like to thank the Ministry of Science, Technology and Innovation (MOSTI) of Malaysia for providing financial support for this research work. This work is sponsored under contract number 06-02-12-SF0346. The authors also wish to thank the University of Nottingham for access to the University of Nottingham High Performance Computing Facility as part of the numerical calculations. The research work also forms part of The Seven South-East Asian Studies Mission (7SEAS) under the
References (70)
“Garden City” in the tropics? French Dakar in comparative perspective
Journal of Historical Geography
(2012)Urban greening to cool towns and cities: A systematic review of the empirical evidence
Landscape and Urban Planning
(2010)Greener and larger neighbourhoods make cities more sustainable! A 2D urban economics perspective
Computers, Environment and Urban Systems
(2015)- et al.
Effects of urban parks on the local urban thermal environment
Urban Forestry & Urban Greening
(2014) - et al.
The interaction of rivers and urban form in mitigating the Urban Heat Island effect: A UK case study
Building and Environment
(2012) Influence of a large urban park on temperature and convective precipitation in a tropical city
Energy and Buildings
(1990)Urban heat island effect and its impact on boundary layer development and land–sea circulation over northern Taiwan
Atmospheric Environment
(2008)Maringá: A British Garden City in the tropics
Cities
(2011)Effects of green space spatial pattern on land surface temperature: Implications for sustainable urban planning and climate change adaptation
ISPRS Journal of Photogrammetry and Remote Sensing
(2014)Urban environment: Defining its nature and problems and developing strategies to overcome obstacles to sustainability and quality of life
Environmental Pollution
(2011)