How Baton Rouge, La., appears to a thermal-image camera.
Recent studies have shown that the urban heat island effect may not be limited to densely populated areas. The Florida Solar Energy Center compared the average temperatures in two Melbourne, Fla. residential subdivisions to a nearby undeveloped nature park. The nature park was heavily wooded, while one subdivision had relatively few trees and a density of 10.1 houses per hectare, and the other a density of only 4.6 homes per hectare and many tall trees. FSEC officials recorded the temperatures at all three sites for one year. While all sites were much cooler than a typical urban area, the results showed the nature park was consistently the coolest. Noticeable temperature differences were recorded between the two subdivisions as well. On average, there was more than a 1-degree C difference between the two sites 93% of the time, with the less-dense housing development consistently cooler.