Scrubbing carbon from sky is new climate gold rush

This summer, Bill Gates huddled in London with representatives of some of the world's wealthiest people, including the Amazon founder, Jeff Bezos, SoftBank founder, Masayoshi Son, and Prince al-Waleed bin Talal of Saudi Arabia.

- DAVID GELLES & CHRISTOPHER FLAVELLE

They were evaluating their joint investments in firms that could help the world combat climate change. Among the businesses in their portfolio, four stood out: They were working to strip carbon dioxide from the atmosphere, for a profit.

The technology, which did not exist until a few years ago, is still unproven at scale. Yet, it has a uniquely alluring appeal. Stripping away some of the carbon dioxide that is heating up the world makes intuitive sense. And with a small but growing number of firms willing to pay for it, investors are jockeying to be first movers in what they believe will inevitably be a big industry that is necessary to help fight global warming. Carbon dioxide removal is the most developed form of what is known as geoengineering, a broad set of speculative technologies designed to manipulate natural systems in order to cool the planet. In the past several years, as climate change has worsened, such ideas have moved from the stuff of science fiction into the mainstream.