Scientists want to spread dust in the upper atmosphere to see if it will stop climate change.
The idea is to dump calcium carbonate, basically chalk dust, into the stratosphere to block some of the sun's rays with the hope of halting the climate from warming.
It's called Stratospheric Aerosol Injection or SAI.
The media calls it Bill Gates' idea, but Gates is only one of many people funding the research and it isn't his idea, it's Harvard's.
The test launch for the project in Sweden was canceled after people complained. But there's likely to be another test in the future because some scientists think this could work, while others say it's a very bad idea.
What Could Possibly Go Wrong? A Lot
A video made by the German science foundation Heinrich-Böll-Stiftung shows how it could all go terribly wrong. It says of Stratospheric Aerosol Injection that "It is unlikely that cooling of the planet could be achieved in a uniform way. SAI would therefore produce regional winners and losers. The total global rainfall would be less. In Asia, SAI could upset the complex system governing the monsoon, on which the water and food supply of 2 billion people depends."
It could also lead to droughts in Africa and flooding in Latin America.
Experts admit they aren't sure what would happen if the sun was dimmed, but we know when it has happened because of natural processes, the result was not good.
A Lesson from 1816
The year 1816 in the United States was called "the year without summer," or "Eighteen hundred and froze to death." Scientists now believe it was a "volcanic winter" created by a huge eruption in the south Pacific. As volcanic ash circled the globe, a strange fog began to appear in the eastern United States and the month of June suddenly saw freezing winter-like temperatures that wiped out crops and livestock and led to famines.
Could the same thing happen from stratospheric aerosol injection? Jens Olaf Pepke Pedersen, Senior scientist at Denmark's National Space Institute doesn't think so.
If it SAI Does Go Wrong, Scientists Think It Would be Reversible
"If it turns out it's a bad idea, it would be easy to stop the experiment," Pedersen said.
But Pedersen also doesn't think manipulating the climate is either good or necessary. Scientists know the earth has warmed one degree since 1900 but admit they don't know the normal earth temperature or if we are simply rebounding from a cold period 200 years ago called Little Ice Age.
And Pedersen says humans and plants both do better in warmer weather than in colder weather.
"There's still more people dying from cold weather than from warm weather," Pedersen said, "The earth has become greener. Even the trees are growing better than they used to."
But if There's No Climate Emergency, Why Bother?
In his new book entitled Unsettled: What Climate Science Tells Us, What It Doesn't, and Why It Matters, Theoretical Physicist Steven Koonin, former Undersecretary of Energy during the Obama Administration, says the weather data itself shows there is no climate emergency.
Koonin says the climate data shows that "Heat waves in the U.S. are now no more common than they were in 1900 and they haven't gone up in 60 years…no global trends in drought or in floods. Greenland's ice sheet isn't melting any more rapidly now than it was eighty years ago. There's no long-term trend in hurricanes over the last hundred years. You wouldn't know that, of course, if you just watched the media."
So Koonin does not think we need to spread dust through the stratosphere.
"It's got a lot of downsides. The most important one is the particles settle out over a couple of years and so you've got to keep putting them up there. We should not think about deploying it unless something really bad happens with the climate," Koonin said.
And Koonin says the good news is that a lot of the bad news you're reading about climate change is wrong.