As fossil fuel use continues apace and a hotter planet edges closer to passing safety limits, some scientists are exploring a controversial technological stopgap: spraying chemicals into the atmosphere to reflect away some of the sun's warmth.
Deploying the technology, using special planes, would be relatively cheap and simple, costing a few billion dollars a year, its backers say.
And it could — if maintained — hold down global average temperatures, potentially staving off increasingly deadly climate-change impacts such as heat waves, they argue.