Hasanuddin Lamit

Street geometry factors influence urban microclimate in tropical coastal cities: A review

Abstract Urban climatologists have moved smoothly towards urban geometry meso-scales as obstruction between buildings, streets, and urban environment. Urban climatologists and designers have expressed that urban geometry parameters affect urban microclimate conditions. Improper functioning of the geometry factors, particularly air temperature and wind speed, can increase the harshness of climate change and Urban Heat Island (UHI) defects, which are more critical in coastal cities of tropical regions. In this regard, the current study aimed to identify the impact of each street geometry factor on urban microclimate through a critical literature review. The research determined a total of twenty seven (27) factors within three clusters; 1) geometry factors, 2) meteorological factors, and 3) streetscape factors. The content analysis calculated the Depth of Citation (DoC) which refers to the cumulative importance level of each factor. The content analysis resulted air temperature (Ta) (DoC = 18 out of 28) is the most important street geometry factor that should be extensively considered in urban microclimate studies in coastal cities. In contrast, the factors (such as air pollution and traffic load) have received a minimum Doc (1 out of 28). The research has also analyzed the importance level of clusters through an expert input study using Grounded Group Decision Making (GGDM) method. The results show that meteorological cluster (92 %), streetscape cluster (86 %), and geometry cluster (85 %) have to be respectively implemented in urban microclimate studies in coastal cities. The research states there are new approaches have not yet been touched by urban climatologist affecting urban microclimate; included; surface materials, sea-borne dust and sand, user’s satisfaction, user’s thermal adaptive behavior. These approaches can potentially exacerbate UHI effects in coastal cities, which need further research.

Heritage contribution in sustainable city

The concept of sustainability has been an integral part of development work since the late 1970s. Sustainability is no longer a buzzword but a reality that must be addressed by cities all over the world. Increasing empirical evidence indicates that city sustainability is not just related to technical issues, such as carbon emissions, energy consumption and waste management, or on the economic aspects of urban regeneration and growth, but also it covers social well-being of different groups living within increasingly cosmopolitan towns and cities. Heritage is seen as a major component of quality of life, features that give a city its unique character and provide the sense of belonging that lies at the core of cultural identity. In other words, heritage by providing important social and psychological benefits enrich human life with meanings and emotions, and raise quality of life as a key component of sustainability. The purpose of this paper, therefore, is to examine the role that built cultural heritage can play within sustainable urban development.

Effect of the position of the visible sky in determining the sky view factor on micrometeorological and human thermal comfort conditions in urban street canyons

Poor daytime and night-time micrometeorological conditions are issues that influence the quality of environmental conditions and can undermine a comfortable human lifestyle. The sky view factor (SVF) is one of the essential physical parameters used to assess the micrometeorological conditions and thermal comfort levels within city streets. The position of the visible sky relative to the path of the sun, in the cardinal and ordinal directions, has not been widely discerned as a parameter that could have an impact on the micrometeorological conditions of urban streets. To investigate this parameter, different urban streets that have a similar SVF value but diverse positions of visible sky were proposed in different street directions intersecting with the path of the sun, namely N–S, NE–SW and NW–SE. The effects of daytime and night-time micrometeorological variables and human thermal comfort variables on the street were investigated by applying ENVI-met V3.1 Beta software. The results show that the position of the visible sky has a greater influence on the street’s meteorological and human thermal comfort conditions than the SVF value. It has the ability to maximise or minimise the mean radiation temperature (Tmrt, °C) and the physiological equivalent temperature (PET, °C) at street level. However, the visible sky positioned to the zenith in a NE–SW or N–S street direction and to the SW of a NW–SE street direction achieves the best daytime micrometeorological and thermal comfort conditions. Alternatively, the visible sky positioned to the NE for a NW–SE street direction, to the NW and the zenith for a NE–SW street direction and to the zenith for a N–S street direction reduces the night-time air temperature (Ta, °C). Therefore, SVF and the position of the visible sky relative to the sun’s trajectory, in the cardinal and ordinal directions, must be considered during urban street planning to better understand the resultant micrometeorological and human thermal comfort conditions.

A decision support tool for a walkable integrated neighbourhood design using a multicriteria decision-making method

Growing concern about transportation emissions and energy security has persuaded urban professionals and practitioners to pursue non-motorized urban development. They need an assessment tool to measure the association between the built environment and pedestrians’ walking behaviour more accurately. This research has developed a new assessment tool called the Walkable Integrated Neighbourhood Design (WIND) support tool, which interprets the built environment’s qualitative variables and pedestrians’ perceptual qualities in relation to quantifiable variables. The WIND tool captures and forecasts pedestrians’ mind mapping, as well as sequential decision-making during walking, and then analyses the path walkability through a decision-tree-

Urban Heat Island of Putrajaya City in Malaysia

The administrative capital city of Malaysia, Putrajaya, is built on the garden city concept. The Putrajaya planning guidelines for sustainable cities suggested that 37% of the development area should be dedicated to green and open spaces. Further, they stated that 50% of the area for car parks and open spaces must be provided with shade trees and grass. Although the garden city concept was applied, the city still experiences high air temperatures. The purpose of this work is to highlight the recent trends in studies of the heat island and surface temperature conducted in Putrajaya city. The study further highlights findings and suggested solutions for mitigating of the heat island in the city.