As the urgency to address climate change intensifies, scientists are exploring creative and sometimes far-fetched methods to cool the planet. One such concept involves grinding trillions of dollars worth of diamonds into dust and dispersing it into the atmosphere. While this may sound like science fiction, researchers have taken a serious look at this unusual proposal.
The idea, published in Geophysical Research Letters, suggests that injecting around five million tons of diamond dust into the atmosphere annually could lower global temperatures by nearly 2.9°F (1.6°C) over 45 years. This cooling effect would help keep the planet just under the critical 2.7°F (1.5°C) warming threshold, beyond which the catastrophic effects of climate change become irreversible. However, achieving this would come at a staggering cost of nearly $200 trillion, making it a highly unlikely approach.
This concept falls under the category of solar geoengineering, a field focused on manipulating the Earth’s atmosphere to reflect more sunlight and cool the planet. Specifically, this technique is known as stratospheric aerosol injection. By releasing fine particles like diamond dust into the atmosphere, the particles would reflect sunlight into space, reducing the amount of heat absorbed by the Earth.
The researchers compared the cooling effects of diamond dust with other aerosol candidates, including sulfur. Using a 3D climate model, they simulated the behavior of these particles in the atmosphere, particularly how they coagulated and how long they remained airborne. Pulverized diamonds performed well in both respects: they resisted clumping together, which is crucial to prevent heat from being trapped, and stayed airborne for longer periods.
Additionally, diamonds have the advantage of not causing acid rain, unlike sulfur, which has been more commonly proposed as a solution.
While diamonds excel in the study, sulfur remains the most practical option, primarily because it’s readily available and inexpensive. “It’s basically free,” said Douglas MacMartin, an engineer at Cornell University whose work was cited in the study.
Sulfur’s effects are also easier to observe in real life, thanks to natural experiments like volcanic eruptions, which release sulfur into the atmosphere. MacMartin noted that sulfur would be easier to disperse through aircraft, whereas diamond dust would require far heavier payloads.
“If you ask me today what’s going to get deployed, it’s gonna be sulfate,” MacMartin said.
In other words, while diamonds may provide a fascinating glimpse into future possibilities, the reality is that we’re more likely to rely on practical solutions like sulfur.
However, exploring unconventional ideas like diamond dust is valuable for broadening our understanding of geoengineering’s potential.
“You need to understand the early-stage physics of potential particles to then have the conversations about broader impact, “Shuchi Talati, founder of the Alliance for Just Deliberation on Solar Geoengineering, emphasized.
While the dazzling idea of using diamond dust to cool the planet may not become a reality anytime soon, it represents the kind of innovative thinking needed to confront the global climate crisis.