Understanding Urban Growth through Heat Islands Using Remotely Sensed Data: Yaounde Case Study, Cameroon

Abstract

Studies in urban dynamics have focused on population growth, urban sprawl and activities expansion to determine, understand and study the phenomenon of urbanization in the world. The methods used in these studies have explore remotely sense data from Global Positioning Systems (GPS), satellite imagery, aerial and ground photography for interpretation, analysis and explanation of urban land use and land cover evolution. This data is often combined with ground observations and other methods in social sciences to understand urban growth. In this article, data is tapped from temperature differences analysis in multi-date satellite images and combined with population statistics, human activities and infrastructure build up to explain the phenomenon of urbanization. The results of the findings will enrich our knowledge in Urban Geography on approaches and methods used in understanding urbanization and its problems. Drawing on case study material from Yaounde in Cameroon, this article examines how remote sensing techniques can help in understanding urban heat island in Yaounde and its negative outcomes on urban population, activity and the environment. As the study shows, urban growth has a direct relation with temperature increase and an inverse relation with vegetation change. Also, Increase in bare surfaces due to deforestation for development and settlement increases surface temperature and vice versa. Vegetation regulates surface temperature by absorbing energy from solar radiation and remission in the form of latent heat through the process of photosynthesis. Analysis of surface temperature increase through remote sensing techniques, urban land use evolution, determinants and implications of Yaounde heat islands constitute the focus of this paper. The implications of rise in surface temperature and relations with urban growth are important for decision making. This knowledge is essential for urban geography research, new methodological approaches to urbanization and policy.