The presence and potential mitigation of Micro-Urban Heat Islands (MUHIs), isolated urban areas within a city that produce “hot spots” for higher than normal temperatures as compared to rural areas or areas of vegetation cover, are an important issue for urban planners. As early as 1995, researchers have attempted to use GIS technology to combine temperature readings with remote imagery to better understand the potential impact of such MUHIs so that such knowledge could be utilized in future plans. Cathy Aniello and her research collaborators performed such a study on an area of Dallas, Texas that contains both new and old neighborhoods as well as tree and vegetation cover and a cleared area around a lake.
The researchers obtained an image of the area and then used an algorithm to pixelate it based on clusters for the different land uses, including tree cover, roads, the lake, and other urban land use. Another algorithm was then used to determine the temperature at each pixel using LANDSAT TM thermal detectors. Using GIS analysis programs they were then able to combine the two into a map of the area that illustrated thermal patterns across the area in a color-coded fashion.
This allowed the researchers to determine that significantly higher temperatures in MUHIs radiated outward whereas tree cover correlated with lower temperatures, and also worked in a radial fashion cooling surrounding areas. This study demonstrates the increased analysis ability that GIS systems provide and the importance of their inclusion in aspects of urban planning.
Aniello, C., Morgan, K., Busbey, A., & Newland, L. (1995). Mapping micro-urban heat islands using LANDSAT TM and a GIS. Computers & Geosciences, 21(8), 965-969.