In a quarry surrounded by the din of heavy machinery Jim Mann crouches down and picks up a handful of tiny black rocks.
“This is my magic dust,” he says with a smile, gently rubbing them between his fingers.
He’s holding pieces of basalt. It’s a hard volcanic rock that is neither rare nor particularly remarkable.
But through a process known as ‘enhanced rock weathering’ it could help to cool our overheating planet.
UN scientists are now clear that reducing greenhouse gas emissions alone won’t be enough to stop dangerous levels of warming. They say there will need to be some carbon dioxide removal – actively taking it out of the atmosphere.
Planting trees is the most natural way of doing this but has its limitations; the CO2 that’s captured is released when the wood rots or burns and there are limits to how widely trees can be planted.
Direct Air Capture (DAC), meanwhile, mechanically sucks CO2 out of the atmosphere and stores it underground; it’s permanent – but does it make…
This article was written by and originally published on www.bbc.co.uk