Difficulty: Summiteer (Level 3)
Scientists say that white or reflective paint is more effective at cooling cities than covering roofs with solar panels or greenery, and it could offer some relief on hot summer days.
Two studies examined the effect of ‘cool roofing’ and found that using white or reflective coatings could reduce outdoor city temperatures by up to 2 degrees Celsius.
Scientists at University College London used a model of Greater London to test various cooling methods against its hottest days of 2018. The results, published in the journal Geophysical Research Letters, found that if adopted widely, cool roofs could reduce the temperature between 1.2 degrees Celsius to 2 degrees Celsius.
Planting vegetation at street level or installing solar panels provided a much smaller cooling effect at about 0.3 degrees Celsius on average.
