Fact check: Bill Gates is not trying to ‘block the sun’s rays’ in the name of climate change

Fact check: Bill Gates is not trying to ‘block the sun’s rays’ in the name of climate change

The claim: Bill Gates is working to block the sun to prevent global warming

Bill Gates’ wealth has allowed him to donate and invest in projects across the globe — it has also made him a frequent target for conspiracy theories. Recently, social media users are claiming Gates is working to block the sun’s rays in order to combat global warming. One example is this April 8 Facebook post, which reads, “Let me get this straight. Bill Gates is working on a way to block the sun’s rays so we prevent global warming. On the other hand we are expected to go to solar powered energy. So how does that work???”

The post is referring to Harvard’s Stratospheric Controlled Perturbation Experiment, which is financially backed by Gates. But this claim, like other reports, misrepresents the nature of the project. The project revolves around the concept of geoengineering, large-scale efforts to reduce the effects of climate change — usually temporarily — on oceans, soils and atmosphere.

At its core, SCoPeX seeks to better understand the efficacy and risks of solar geoengineering. In order to do so, scientists need to determine if there are aerosols that could reduce or eliminate ozone loss without increasing the chance of other risks. The experiment involves launching a high-altitude balloon about 12 miles into the atmosphere, according to its website. A small amount of material is then released to create a “perturbed air mass” about 100 yards wide and a half-mile long. Instruments carried by the balloon monitor that region for changes in aerosol density, atmospheric chemistry and light scattering. In other words, it’s a very small-scale project, far from the climate-altering claims about it that have surfaced on social media.