Geoengineering solutions could prevent irreversible climate crisis, study finds

Geoengineering could prevent the potentially catastrophic climate-change tipping points that loom just ahead, reports a new Cornell study. Cornell earth system scientist Charles Greene, the lead author of the study published in the September-October issue of Solutions magazine (Vol. No. 5), says time is running out, yet governments have done little to reverse rising carbon dioxide (CO₂) levels. Many scientists warn that to avoid excessive warming, sea level rise and extreme weather, CO₂ in the atmosphere needs to be reduced to 350 parts-per-million (ppm) by the end of this century from the current level of around 390 ppm. If actions aren't taken soon, ocean acidification and greenhouse warming in the atmosphere will reach a tipping point this century that will take more than 1,000 years to reverse, the paper warns. It suggests that one way to reduce atmospheric CO₂ by the end of the century is by setting up fields of air-capture devices that absorb CO₂, very similar to the carbon capture and storage technology being developed for coal plants. The devices would use algal bioenergy as a power source to capture, extract and pipe CO₂ for storage or industrial use. Algae provide a preferred bioenergy source relative to land plants because they are more productive, more efficient in their use of nutrients and do not need to compete with food crops for prime agricultural land, Greene said. The price tag for using this technology over the remainder of the century?