Bill Gates wants to spray millions of tonnes of CHALK into the stratosphere

Harvard University experts will send a large balloon 12 miles above the Swedish town of Kiruna and have it drop 2kg of chalk dust into the stratosphere. https://www.dailymail.co.uk/sciencetech/article-9392641/Bill-Gates-wants-spray-millions-tonnes-CHALK-stratosphere.html?ns_mchannel=rss&ns_campaign=1490&ito=1490