Satellite imagery shows air pollution rise in tropical ‘megacities’

has used satellites to track air pollution changes in some of the world’s fast-growing tropical cities. Some of these cities will house more than 50 million people by 2050, but there is almost no on-the-ground measurement of what people are breathing.

We are all used to seeing satellite images on television weather forecasts. They are also used routinely to track dust storms including arrival of Saharan dust in the…