Accelerating rock weathering can help decarbonize the atmosphere

It's a bleak midwinter day at Orrock Quarry in Fife, East Scotland. Steep, jagged cliffs rise above noisy machines that grind an endless stream of freshly quarried rock. A burly man in muddy HiVIS-style work clothes picks up a handful of black dust from a nearby pile. I learn that it is basalt dust, a secondary waste from a quarry, which, despite its unsuitable environment, is the basis of one of the most interesting climate solutions today.

Basalt dust is the feedstock for a new, naturally-based carbon removal technology called enhanced rock weathering (ERW), designed to permanently sequester CO2 in the atmosphere. This is a geological process that has been occurring naturally for millions of years, but several companies are now accelerating it.
"There is incredible momentum around the world in enhanced rock weathering and its uses across a range of different value chains," says Antti Vihavainen, CEO of carbon removal platform Puro.earth. Rock weathering on steroids To combat the harmful effects of climate change, it is necessary to remove some of the billions of tons of CO2 we have been releasing into the atmosphere for decades. The problem with CO2 is that it stays in the atmosphere for hundreds of years, so even if all countries managed to reduce greenhouse gas emissions to zero today, the planet would not cool down, it would just stop warming. The Intergovernmental Panel on Climate Change (IPCC) estimates that we need to remove ten billion tons of CO2 per year by 2050 and 20 billion tons per year thereafter to prevent dangerous climate change.

To this end, a whole range of carbon removal technologies are emerging – from the simple concept of growing trees to giant fans that suck CO2 directly from the air – that scientists and politicians are counting on to remove CO2 from the atmosphere and seal it up.