Could injecting diamond dust into the atmosphere help cool the planet?
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Prior research has shown that Earth is at or near a tipping point—warming of the planet has led to changes in global weather patterns that may only grow worse as the planet grows warmer. If true, some argue that the only solution at this point is rapidly finding a way to cool the planet. Some scientists have proposed deploying millions of devices that pull carbon from the air, which could then be sequestered.
The problem with that is, if we have hit a tipping point, removing the carbon will not help—we have to find a way not just to reduce warming, but to actively cool down the planet. The only way to do that, most in the field agree, is to inject aerosols into the atmosphere to reflect sunlight and heat back into space.
The leading candidate for such an endeavor right now is sulfur dioxide. Because it is spewed naturally into the atmosphere by volcanoes, scientists have a pretty good idea of what would happen if humans began injecting it artificially. The downside is that it could cause acid rain around the globe. It could also harm the ozone layer and would likely disrupt weather patterns in the lower atmosphere.
In this new effort, the researchers wondered which sort of material would best serve as a planet cooling medium. To find out, they built a 3D climate model that showed the impact of adding aerosols to the atmosphere. The software also included effects of different aerosols, such as light and heat reflection, how aerosols would eventually settle to the ground, and whether they would clump together in the atmosphere, retaining more heat.
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