In a worst-case scenario, blotting out the sun may be our only hope.
Bill Gates is a man who recently suggested the world should eat 100% synthetic beef, has argued that bitcoin is bad for the planet, co-founded Microsoft, and remains one of the richest people in the world.
He is also very interested in dimming the light from the sun to reduce or delay the effects of climate change, according to a forthcoming study from the Bill Gates-backed Harvard University Solar Geoengineering Research Program — which aims to evaluate the efficacy of blocking sunlight from reaching our planet’s surface.
However, the concept of solar geoengineering sounds dense. What is it, and why do people think it’s necessary to fight climate change?
Bill Gates supports research into creating fine particulates to reflect sunlight
Geoengineering refers generally to technologies capable of changing the Earth’s physical qualities on the most colossal scales possible. For example, cloud seeding involves planes dumping particulate matter to make them transform into rain. There’s also carbon capture, which gathers and stores emissions below the Earth’s surface. But blocking the sunlight has to be the most extreme version yet to see serious scientific consideration.
Recently, the National Academies of Sciences, Engineering, and Medicine (NASEM) released a report pushing for the U.S. government to spend at least $100 million in the pursuit of deeper studies of geoengineering.
There are multiple approaches to ways of blocking sunlight from hitting the surface or atmosphere of Earth — signified under the umbrella term “solar geoengineering.” The most common method involves reflecting sunlight away from the planet via aerosol particles in the atmosphere, but this was a fringe idea until very recently.
This is the catalyzing event for the 2013 film “Snowpiercer,” where Earth has frozen into a lifeless snowball after attempts made to block sunlight went terribly wrong. The mechanism responsible for aerosol solar geoengineering is fairly simple, but, in reality, the physical structure of the particles themselves is more complex.
And, nature might have triggered aerosol solar blocking in the past. The 2010 Icelandic volcano — which blocked the whole sky far into the depths of Europe — was an atmospheric aerosol event. It’s also suspected that the mega-meteor strike that likely doomed the dinosaurs smothered the planet in a rich layer of aerosol dust. Practically any common substance can be reduced to an aerosol — given the right conditions. All it has to do is be small and fine enough to float in the clouds like a gas.
Blotting out the sun could one day become our last hope against climate change
The researchers involved with the forthcoming Harvard project — called the Stratospheric Controlled Perturbation Experiment (SCoPEx), have urged for the study of solar geoengineering, just in case we need to take drastic steps to “hit the brakes” on climate change. Funded by Bill Gates, the study aims to execute exploratory, small-scale experiments in the atmosphere.
“We plan to use a high-altitude balloon to lift an instrument package approximately 20 km (12.42 miles) into the atmosphere. Once it’s in place, a very small amount of material (100 g to 2 kg) will be released to create a perturbed air mass roughly one kilometer long and one hundred meters in diameter,” read a statement on the SCoPEx official web page.
“We will then use the same balloon to measure resulting changes in the perturbed air mass including changes in aerosol density, atmospheric chemistry, and light scattering.”
There is much left to understand about which susbtance should be used for the tests. Calcium carbonate is bountiful and harmless (we use it in Tums medication). But it could have unpredicted effects in the stratosphere. Meanwhile, the NASEM’s prepublication report organized a committee of 16 international scientific experts to develop a gameplan about further studies into geoengineering research.
“Globally, 2015-2019 were the 5 warmest years in the instrumental record,” said Researcher Chris Field, in the NASEM study. “The creation of this study committee is one response to the need for understanding the full range of options for dealing with the climate crisis.”
It’s difficult to say whether blotting out the sun is a bright idea, which is why everyone involved (including Bill Gates himself) is emphasizing a need to merely research the process of filling the atmosphere with aerosol particulates — instead of jumping the climate gun and experimenting on a still-thriving (relatively, surely) civilization.
It’s always good to have a plan B, and if the steps taken by countries, entities, and corporations don’t slow the advance of climate change, something like solar geoengineering may become our last hope.