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Hey citizens of Earth, Trace here.
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Most climate scientists agree that climate change is happening and that humans are to
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blame.
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Greenhouse gasses like carbon dioxide and methane that we've been pumping into the
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atmosphere have been capturing heat from the sun's rays, and average annual temperatures
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have been on the rise since the industrial revolution.
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The common wisdom is we need to drastically cut back the amount of greenhouse gasses we
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emit, but what if instead we just reduced the amount of sunlight we receive so greenhouse
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gasses can't soak up as much heat?
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If that sounds crazy to you, it's probably because it kind of is.
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Projects that would accomplish that would require engineering feats on a global scale,
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hence why it's called “geoengineering.”
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Geoengineering ideas to fight climate change stretch all the way back to 1965 when science
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advisors to President Lyndon B Johnson proposed covering 13 millions square kilometers of
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ocean with reflective particles to bounce 1% of the sun's rays back into space.
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As you can tell by how un-fabulous our oceans are right now, we never ended up glitter bombing
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the Pacific.
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But geoengineering ideas still crop up from time to time, lurking at the fringe of the
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climate change discussion.
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They run the gamut from painting everyone's roof white, to drone ships that make ocean
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clouds brighter, to launching a giant mirror into space.
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All of these plans have one thing in common though: They're all trying to increase the
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Earth's albedo, which is a measure of how much light we reflect back into space, as
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well as the name of my hispanic alter ego.
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There are a lot of reasons none of these ideas have gained any ground though.
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First, as you might imagine, intentionally changing the entire world would be kind of
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expensive.
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And in a time when the scientific community is STILL trying to convince the powers that
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be that climate change is both a real and serious threat, it's going to be hard to
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get those same powers to shell out funding for something crazy like a mirror in space.
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Ironically, the cost of these projects will likely be relatively small compared to fixing
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the damage caused by climate change in the long run.
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Second, these ideas may have side effects that would change the world in unintended
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ways.
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One of the most popular and realistic geoengineering proposals is to release sulfate particles
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into the air, which would combine with water vapor to form aerosols that reflect sunlight.
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Large volcanic eruptions do the same thing and cause temperatures to dip for a few years.
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Unfortunately, these sulfates also react with chlorine in the atmosphere, converting it
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to a form that destroys the ozone layer.
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Basically these geoengineering projects might be like that time you tried to fix your car
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yourself, and it worked for a bit until it broke in a more expensive way.
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But the biggest reason geoengineering still isn't considered the solution to climate
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change is because it doesn't solve the root of the problem, if anything it encourages
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us to never actually fix it.
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We have a hard enough time changing our lifestyles now, and if people learned that we could spray
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sulfates in the atmosphere every few years and we could keep burning coal, oil, and natural
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gas, why would anyone change?
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And if we don't curb the rate we put greenhouse gasses into the atmosphere, then the problem
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will only get worse, and the situations we'll have to engineer our way out of will get more
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extreme.
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Another ambitious geoengineering idea sprung up lately: replenishing arctic ice with millions
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of windmills.
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Jules gets into the details here.
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So knowing the risks and rewards of geoengineering, are you on board or do you think we should
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focus on cutting emissions.
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Let us know in the comments and come back here every day for more.
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Thanks for watching!
