Spraying diamonds into the atmosphere to cool the Earth? 💎

Sending diamonds into the sky to cool the Earth? That's the bold project some scientists are considering. An improbable solution that warrants consideration.

A group of researchers is exploring an original idea: injecting diamond dust into the atmosphere to fight global warming. This approach is based on solid scientific principles.


Recent studies, published in the journal Geophysical Research Letters, suggest that injecting five million tons (4.5 million metric tonnes) of these particles annually could lower the Earth's temperature by about 1.6°C (2.9°F). Such a reduction could help keep global warming below the critical threshold.

However, achieving this ambition would require a colossal investment and a long-term commitment. In fact, researchers estimate that this operation would need to be carried out every year for around 45 years to maintain these injections, with the total cost reaching no less than 200 trillion dollars.

This project falls within the scope of solar geoengineering, a technique that involves dispersing aerosols into the stratosphere. By reflecting sunlight, these particles could mitigate the planet's warming.

Using a 3D climate model, scientists simulated various aerosols, including diamond and sulfur. The effectiveness of these particles depends on their ability to remain suspended and avoid coagulation, a key factor influencing their impact.

The results show that diamond dust has a distinct advantage: its stability in the atmosphere. Unlike sulfur, it doesn't cause acid rain, a feature that could grant it certain environmental benefits.

However, sulfur remains an option to consider. Easy to transport and disperse, it is a less expensive and well-understood solution due to its behavior during volcanic eruptions. The researchers acknowledge that it might be more practical in the short term.

Ultimately, the idea of spraying diamonds should not overshadow the need to address our greenhouse gas emissions. Geoengineering could be a temporary tool, but the fight against climate change must primarily focus on concrete and sustainable actions.

What is solar geoengineering?

Solar geoengineering is an approach that seeks to alter the Earth's climate by reflecting a portion of sunlight to reduce warming. This can involve injecting aerosols into the stratosphere, thereby blocking a fraction of solar radiation and helping mitigate rising temperatures.

The aerosols used in this technique, such as sulfur dioxide, can have undesirable side effects, including the formation of acid rain or impacts on the ozone layer. Researchers are therefore exploring alternative materials, like diamond dust, which could offer a less harmful solution while maintaining similar efficacy in cooling the planet.

However, these solutions remain temporary and must be complemented by efforts to reduce greenhouse gas emissions.