London, UK - The latest wacky weapon to fight climate change is a proposal to install artificial trees which could soak up carbon dioxide.
The suggestion comes from the Institution of Mechanical Engineers (IME). It's not a new idea, but it's the first time it's been put forward as being practical and feasible.
The report envisages devices which, like trees, can remove CO2 from the atmosphere - as air passes through it, CO2 sticks to an absorbent material. The CO2 is then removed and buried underground in the same way as conventional carbon capture and storage (CCS).
"At an estimated cost of $20,000 for each unit, the UK would require 100,000 'trees' (each absorbing ten tonnes of CO2 per day) to capture the entire nation's non-stationary and dispersed emissions," says the report.
Artificial trees are just one part of the IME's (perhaps just a little ambitious) 100-year plan to combat climate change. The team evaluated hundreds of geoengineering ideas, but found just three to be workable in the near future.
The IME also proposes coating buildings with algae, which would soak up CO2 and could then be harvested for biofuel. "The advantage of this proposal is that no additional land is required - therefore it will not affect existing and future food production or other important land uses," says the report.
A third suggestion is to make buildings more reflective - less effective than the other two, says the IME, but still worth doing.
Geoengineering: Giving us the Time to Act is available here.