“You can’t shade the sun with a finger,” but science and technology might be able to. According to Forbes, Bill Gates is supporting a project to “cool” the Earth by dimming sunlight. Scientists from Harvard University are doing research named “Stratospheric Controlled Disturbance Experiment” (SCoPEx in English) with the goal of accomplishing that sunlight is reflected outside our planet’s atmosphere.
To do this, tones of non-toxic calcium carbonate (CaCO3) would be sprayed into the atmosphere.
According to the project page, “SCoPEx is a research experiment to increase the understanding of stratospheric aerosols that may be significant for solar geo-engineering.” The project will begin conducting tests, which will include the release of a balloon with scientific equipment that will not spray CaCO3 but will serve as a maneuvering test as well as an exploration of communications and operating systems.
“We plan to launch an instrument package around 20 kilometres into the stratosphere using a high-altitude balloon. Once in situ, a modest amount of material (100g 2 kg) will be released to generate a disturbed air mass one kilometre long and one hundred metres wide. Then, using the same balloon, we’ll measure the changes in the disturbed air mass, such as changes in aerosol density, atmospheric chemistry, and light scattering,’ they add.
