Links
Urban Heat Island
Everyone knows? Well, I’m quite amazed then, why so many people who live in hot regions
opt for fashionable dark-
This tendency and the loss of vegetation plays a major part in the rapid develoment
of the heat island effect in urban areas. So, should we paint our towns and cities
white? There are many arguments for it, but might seem over-
In the US, around half the population lives in heat islands. The worldwide trend of urbanisation means that the populations of other countries experience the same or even worse adverse heat effects. Los Angeles is a typical example of this trend. Local authorities and government agencies are now evaluating possibilities to, at least, limit the adverse heat island effects.
“Painting the town white” and “cool communities” have become slogans and the bases for intensive sudies. According to one study, a combination of planting trees and lightening the roof and pavement colours could lower the average maximum summer temperatures in Los Angeles by 30C (50F), and reduce the need for mechanical cooling by 18%., saving around US$170 million p.a. in energy costs.
Since excessive heat also triggers ozone production, the result of lower temperature
would also see around 10% less days with smog. The same study goes even one step
further, I quote: “With white roofs, concrete-
Next
Index
Previous
The Oxford dictionary defines albedo as “the proportion of the incident light or radiation that is reflected by a surface…” and it originates from the Latin word albus meaning white or whiteness. The reflectivity has a value and number 1 represents 100% reflectivity, or a very bright surface, and any fraction of 1 tells us that the surface is less reflective, up to the value of 0 which is complete darkness.
Everyone knows that a dark-