Assessing The Microclimate of Green and Less-Green Tropical Landscape Environment Aniza Abu Bakar and Nurhayati Abdul Malek Department of Landscape Architecture, KAED International Islamic University Malaysia Gombak Campus, P.O. Box 10, 50728 Kuala Lumpur MALAYSIA aaniza@iium.edu.my Abstract: - Landscape settings shape the microclimate or thermal performance of the outdoor environment with vegetation and ground surface materials as among the affecting variables. This paper presents the microclimatic impact of landscape settings of two sites with different landscape environment during the wet and dry monsoon seasons of the tropical environment of Malaysia. The study involves field measurement of air temperature, relative humidity and wind environment from 0800hr to 1700hr, conducted on several days of the said monsoon regimes. The results show significant results in terms of the magnitude of air temperature differences between the studied sites, with similar patterns observed on the relative humidity. The wind environment seems to be also affected by the landscape settings. Key-Words: -ground surfaces, microclimate, vegetation 1 Introduction The process of urbanization which involved changes in the natural landscape where more hard surfaces were introduced has led to the urban heat island (UHI) phenomenon among others. This is observed particularly in cities in developing countries, and the majority of these cities lay close to the equatorial line of tropical climates. The UHI further exaggerates the already hot environment of a tropical environment. The role of vegetation in modifying the climate particularly in urban areas is acknowledged following its cooling effect on the evaporation process [1]. Hence, two sites with different landscape setting – green and less-green were identified in this study to see the impact of their landscape component on the microclimate. 2 Urbanization and microclimate modification In hot-humid climate, the people are struggling to live comfortably due to the increment of air temperature that is further exaggerated by the UHI effect where significantly high air temperature in densely built environment is observed as compared to rural temperatures. Significant reduction of natural surfaces including the vegetated surfaces is commonly found in cities following the urbanization. This is among the factors that contributes to the UHI. 2.1 Characteristics of tropical climate of Malaysia There are two main monsoon regimes in Malaysia. The South-West monsoon (dry season) starts from late May or early June, and ends in September. The North-East monsoon (wet season) starts in early November and ends in March. It is observed that high dry bulb temperature and less rain are observed during the dry season, while, on the contrary, low dry bulb temperature, solar radiation and high relative humidity and rainfall are observed during the wet season. In between these two monsoons, which is the inter-season, high solar radiation and low relative humidity is observed. Particularly for Kuala Lumpur, when analysed by the hour, high dry bulb temperature (≥31ºC), high solar radiation (594.4 – 625Wh/m 2 ) and low relative humidity (≤65%) is observed between 1100hr to 1300hr [2]. 2.1.1 Wind environment for tropical regions Wind is an important asset in hot-humid regions. It is needed all year round to cool the streets by removing excess heat, and it is also seen as a potential source to cool the building via cross- Recent Advances in Environment, Ecosystems and Development ISBN: 978-1-61804-301-6 23