The city of Johannesburg contains over 10 million trees and is often referred to as an urban forest. The intra-urban spatial variability of the levels of vegetation across Johannesburg’s residential regions has an influence on the urban heat island effect within the city. Residential areas with high levels of vegetation benefit from cooling due to evapo-transpirative processes and thus exhibit ...

Atmospheric blocking is a long standing structure stalled in the mid-troposphere which is often associated with extreme weather events such as droughts, heatwaves, flood and cold air outbreak. A striking atmospheric blocking is identified to persist over the US during 13–17 August 2007, exacerbating the existing drought over the Southeastern US. This pronounced blocking event not only intensifi...

Globally, there is a rapid development of urban heat island (UHI) detection tools, and their results can be accepted regardless accuracy in measuring the real impact phenomenon. In this study, we investigated various UHI tools analysed findings to better interpret reliability. The current research adopted remote sensing field measurements including those using air temperature monitors thermal i...

With global warming forecast to continue into the foreseeable future, heat waves are very likely to increase in both frequency and intensity. In urban regions, these future heat waves will be exacerbated by the urban heat island effect, and will have the potential to negatively influence the health and welfare of urban residents. In order to investigate the health effects of the urban heat isla...

The urban heat island effect 1 can be detected throughout the year, but it is of particular public policy concern during the summer, because higher surface air temperature is associated with increases in electricity demand for air conditioning, air pollution, and heat stress–related mortality and illness (Rosenfeld et al. 1995; Nowak et al. 2000; Sailor et al. 2002; Hogrefe et al. 2004). In New...

Heat stress is one of the most severe climate threats to human society in a future warmer world. The situation is further exacerbated in urban areas by urban heat islands (UHIs). Because the majority of world’s population is projected to live in cities, there is a pressing need to find effective solutions for the heat stress problem. We use a climate model to investigate the effectiveness of va...

This paper presents a methodology to approximate the urban heat island effect by using a PostgreSQL database and CitySim software, a simulation tool to evaluate urban energy flows. A ground temperature model has been developed for shallow depths (until 4m), which reproduces the phenomena of heat transfer into the ground on an hourly basis. This model is further used to predict the outdoor groun...

Urban heat islands are one of the most critical urban environment heat problems. Landsat ETM+ satellite data were used to investigate the land surface temperature and underlying surface indices such as NDVI and NDBI. A comparative study of the urban heat environment at different scales, times and locations was done to verify the heat island characteristics. Since remote sensing technology has l...

Urbanization is a global problem with demographic trends. The urban heat island plays a dominant role in local climate systems. Despite existing efforts to understand the impacts of multiple urbanization factors on the urban heat island globally, very little is known about the attribution of urban heat island magnitude to urbanization in different locations or developmental phases. In this stud...