It’s an idea that sounds like it belongs in the latest science fiction blockbuster.
But spraying millions of tonnes of diamonds into the sky could finally be the solution to global warming that we’ve been searching for.
That’s according to scientists from the Institute for Atmospheric and Climate Science, ETH Zurich, who set out to investigate the effects of spraying various aerosols into the atmosphere to cool Earth.
While previous studies have focused on sulphur dioxide, the researchers found that diamonds would actually be much more effective.
In fact, their models show that shooting five million tonnes of diamond dust into the stratosphere each year could cool our planet by an impressive 1.6°C.
However, in news that will come as no surprise, this would come at a hefty cost.
The researchers predict that such a project would cost nearly $200 trillion (£153 trillion) over the remainder of this century.
It’s an idea that sounds like it belongs in the latest science fiction blockbuster. But spraying millions of tonnes of diamonds into the sky could finally be the solution to global warming that we’ve been searching for (stock image)
Global emissions of greenhouse gases are growing year-on-year – with devasting effects on Earth’s temperature.
Last month was the second-hottest September on record, with the global average air temperature hitting 61.1°F (16.17°C).
What’s more, several months in 2024 have broken records, becoming the hottest ever for that particular month – namely January, February, March, April, May and June.
Climate scientists around the world are frantically looking at various measures to slow this warming – including removing greenhouse gases from the air, and limiting future emissions.
However, in their new study, the team set out to investigate whether we could cool our planet by spraying particles into the air that reflect sunlight – a technique known as stratospheric aerosol injection (SAI).
Most previous SAI research has focused on injecting sulphur dioxide (SO2) into the air – a process that occurs naturally during volcanic eruptions.
However, as the researchers point out in their study, published in Geophysical Research Letters, this is subject to ‘several limitations’.
Not only would sulphur dioxide react to cause acid rain around the globe, but it could also harm the ozone layer and wreak havoc on weather patterns.
The team set out to investigate whether we could cool our planet by spraying particles into the air that reflect sunlight – a technique known as stratospheric aerosol injection (SAI) (stock image)
Instead, the team modelled the effects of spraying six solid substances – diamond, calcite, aluminium, silicon carbide, anatase, and rutile – into the stratosphere.
Their model analysed the effects of each particle over a 45 year time period, including how it would be transported around the world, how it would absorb or reflect heat, and whether or not it would clump.
The results revealed that diamond particles were the best at reflecting heat, while also staying aloft and not clumping.
And because diamonds are inert, they would not react to form acid rain.
‘The resulting side-effects on circulation and climate especially from diamond injections could be substantially reduced compared to SO2, making diamond particles most suitable for SAI from an optical properties perspective among the materials investigated here,’ the researchers explained.
However, to achieve 1.6°C of cooling – enough to stave off the worst consequences of global warming – you’d need a whole load of diamonds.
Speaking to Science, Sandro Vattioni, lead author of the study, revealed that you’d need to spray five million tonnes of diamond particles into the stratosphere every year.
This would cost approximately $200 trillion (£153 trillion).
To put that into perspective, that’s roughly 800 times more than the net worth of Elon Musk, who is currently the richest person in the world!
Based on the findings, it’s highly unlikely that spraying diamonds into the sky will become a reality any time soon.
However, the researchers hope their study will spark further research into SAI alternatives.
‘We suggest further research on agglomeration processes in turbulent aircraft wakes as well as on measurements of optical properties of a variety of potential solid particle materials,’ the team concluded.
