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September 4, 2025

Dimming the sun, refreezing the ice: VCs flirt with geoengineering

Is there a venture case behind large-scale modification of the planet’s systems? 


Freya Pratty

5 min read

Photo: BALAZS GARDI

Two years ago, a Californian startup, Make Sunsets, pumped a few grams of sulfur dioxide into a series of weather balloons and launched them into the stratosphere.

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Freya Pratty

Freya Pratty is Sifted's associate editor. She covers UK tech and leads Sifted's investigations. Follow her on X , LinkedIn and Bluesky

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