Such cool roofs could cut temperatures by roughly 2 6 degrees fahrenheit in california s cities and by 3 2 degrees in cities like washington or new york.
White roofs and global warming.
No matter what the actual contribution of white roofs in reducing the urban heat island effect a reflective roof can grant homeowners temperature reduction and reduced air conditioning costs especially where summers are warm.
The white roof project points outs that nearly 16 000 people died from heat related cause between 1970 and 2004.
The urban heat island can be a killer.
That effect held regardless of global.
Oleson found that even if every city building roof and stretch of urban pavement in the world were painted white it would only delay global warming by 11 years.
By cooling temperatures in the summer white roofs should lessen the need for air conditioning which in turn reduces electricity use greenhouse gas emissions and warming.