Scientists are sucking carbon dioxide from the air with giant fans and preparing to release chemicals from a balloon to dim the sun’s rays as part of a climate engineering push to cool the planet.
Backers say the risky, often expensive projects are urgently needed to find ways of meeting the goals of the Paris climate deal to curb global warming that researchers blame for causing more heatwaves, downpours and rising sea levels.
The United Nations says the targets are way off track and will not be met simply by reducing emissions for example from factories or cars — particularly