英语翻译
Builders have known for many years that white roofs reflect sunlight and lower the cost of air conditioning.But now scientists say they have found a new advantage:slowing global warming.
Hashem Akbari believes that whitening 100 of the world's largest cities could make the influence of the expected emissions smaller over the next ten years.
White buildings and surfaces reflect far more sunlight than dark ones.Reflected sunlight does not increase the greenhouse effect.unlike the heat energy sent out by dark surfaces heated by the sun.
Dr Akbari,of the Lawrence Berkeley National Laboratory,California,also argues that if built-up areas were made white,less heat would stay within them,alliowing people to use their air conditioners less,which use a lot of power.
Dr Akbarihas found out that making 100 of the largest cities white would increase the sunlight reflected by Earth by 0.03%.He believes it would cancel out the warming caused by 44 billion tons of carbon emissions.
"Roofs are going to have to be changed one by one and to make that effort at a very local level,we need to have an organization to make it happen,'says Dr Akbari.
He argues that while the action would not solve the problem of climate,it would slow it.
"We can give the environment time to breathe.'he says.'I just don't see a disadvantage of this idea.It gives everybody advantages and you don't have to make hard efforts to make it happen.'
Akbari and his partners say they will try to persuade the United Nations to organize big cities to change the materials of their roofs.