We’re talking about solar geoengineering, a controversial idea that relies on spreading long-lasting reflective particles into the upper atmosphere to block sunlight and slow global warming. It sounds like science fiction, but philanthropist and Microsoft founder Bill Gates is determined to do so. The goal is to send more than 800 giant planes every day that would release millions of tons of calcium carbonate (a harmless component of limestone) to a height of about 20 kilometers above the surface of the Earth and then spread all of it around the stratosphere (the layer of the atmosphere between the troposphere and the mesosphere).
In theory, this dust would create a giant shield whose particles would reflect the sunlight and return the heat to space, attenuating all the energy that passes through the atmosphere and protecting the Earth from increasing temperatures.
ScoPEX project
The project in question has been baptized as ScoPEX ( Stratospheric Controlled Perturbation Experiment ) and is developed by scientists from the American University of Harvard and will carry out its first contact this year in the city of Kiruna (Sweden).
So is the project moving forward? That’s how it is. After many technical and regulatory disputes, scientists have proposed a test flight in June 2021, although they will not spray CaCO3 into the atmosphere, instead it will be the launch of a research balloon designed to perform as maneuvering and exploration tests of communications and operating systems : you will drop small amounts of chalky dust and observe its effects. The initial test has a cost of 3 million dollars.
“We plan to use a high-altitude balloon to lift an instrument package approximately 20 km into the atmosphere. Once in place, a very small amount of material (100 g 2 kg) will be released to create a disturbed air mass approximately one kilometer long and one hundred meters in diameter. Then we will use the same balloon to measure the resulting changes in the disturbed air mass, including changes in aerosol density, atmospheric chemistry and light scattering, ” the scientists explain.
It is a strange and ingenious solution to try to slow down the amount of radiation that reaches the Earth’s surface and cool the planet , which could repair the ozone layer, since it would react with the molecules that destroy it and the existing holes would be closed.
The main obstacle
The project is not without controversy because no one knows what exactly will happen if all that calcium carbonate is released because the reaction in the atmosphere may be different from the experiments done in the laboratory. What’s more, many scientists are critical of this idea given the possibility of having to face unpredictable risks for making this change artificially on our planet. Could it damage the ozone layer instead of restoring it?
Environmentalists also fear that a “dramatic” change in mitigation strategy will become a “green light” for greenhouse gases to continue to be emitted without any variation in current consumption patterns.
Reference: Harvard University
