Scientists are to copy the effects of a massive volcanic eruption to block the Sun’s rays and combat global warming.
As part of a £2.3million ($3million) experiment partly-funded by Microsoft’s Bill Gates, a team from Harvard University will spray tiny chalk particles into the atmosphere 12 miles above the Earth to reflect some of the Sun’s rays back into space.
They hope this will have a similar effect to an erupting volcano releasing sulphur dioxide. In 1991, Mount Pinatubo erupted in the Philippines, releasing 20million tons of sulphur dioxide. That cooled the planet by 0.5C for 18 months.