White beats global warming

White may soon be the colour of a new, green world. According to a new study, white paint may help beat global warming. The study conducted by Hashem Akbari of the Lawrence Berkeley National Laboratory, California, US, suggests painting roads and rooftops of buildings white to reflect sunlight to delay global warming.

The idea takes inspiration from the old whitewashed villages in southern Europe and North Africa.

Akbari is now working to launch a campaign to paint the world white and wants the largest cities in the world to initiate a united effort to reflect more solar energy by replacing dark-surfaces like roads and roofs with something more reflecting.

This simple solution could usher in dramatic results as studies have repeatedly shown that buildings with white roofs stay cooler in summer.

The change reduces the amount of heat in built up areas allowing people to switch off air conditioning.

White surfaces dramatically increase the amount of reflected heat reducing the need of air conditioning. Akbari has received support from groups in several US cities including Houston, Chicago and Salt Lake City. Akbari maintains that his plan is more practical than other geo-engineering ideas.

Scientists point out that the plan does not address other aspects of the global warming challenge like growing acidification of oceans as extra carbon dioxe dissolves. But according to Akbari the cooling effect and energy savings in cities would be welcome. He says that the  simple solution would benefit everybody without having to conduct hard negotiations. He adds that the atmosphere would get time to breathe. 

An objection that could be raised would concern the desirabilty of shimmer of white-surfaced roads and streets with reflective roofs. Akbari notes, however, a transition from near-black asphalt to gray would also sufficiently increase the reflection of sunlight. Also materials could be added to darker paints that would reflect more of the infrared light that is currently being bounced back.