Geo-engineered Artificial Forests to Capture CO2

A forest made up from thousands of artificial trees could be established as a vast carbon sink, a group of engineers propose in a new report.  They envisage 100,000 man-made trees being planted within the next two decades, and the plan is just one of three similar geo-engineering ventures put forward by representatives of the Institution of Mechanical Engineers. Geo-engineering, they say, is crucial in the fight against climate change.

Speaking to the BBC, Dr Tim Fox, the head author, urged against geo-engineering (deliberate manipulation of physical and/or biological elements of the  Earth System) being considered as a climate change solution in its own right, but said geo-engineering technologies should be deployed in tandem with other mechanisms.

A number of climatologists forecast that the global window to cut back on emissions of carbon dioxide and other greenhouse gases is limited in duration.  Once it shuts, the atmosphere’s total volume of CO2 will push temperatures up to a dangerous level, they say.  On this basis, the Institution of Mechanical Engineers highlight geo-engineering as a stop-gap measure, pending full deployment of permanent emission-reduction efforts.

Geo-engineering the Climate

According to the University of East Anglia’s Nem Vaughan, the report focuses on several different ways of geo-engineering the climate.  One involves directing solar rays away from the earth, another, CCS (carbon capture and storage).  “The first category attempts to cool the planet by reflecting some of the sunlight away”, Vaughan explained, adding: “The problem with this is that it just masks the problem.”

The engineers behind the report analysed a large number of geo-engineering options, concluding that only three were viable and deployable based on present technological limits.  These are artificial forests, small-scale urban carbon sinks and solar reflection technologies.

CO2 Capture

The artificial trees would effectively use a filter to scrub the air of CO2.  The filter would then be emptied and the CO2 put into storage.  According to Dr Fox, artificial trees have the potential to comprehensively outperform natural trees when it comes to CO2 capture.

The small-scale carbon sinks would be attached to buildings and contain algae (the study refers to the technology as ‘algae-based photo bioreactors”).  These would work by scrubbing the air of CO2 when photosynthesis is taking place.

Lastly, there is the idea of mirroring solar rays away from the earth, the best way of doing which would be to add reflective devices to the roofs of buildings, or to factor them into to future construction projects. 

In all instances, the report says, additional research and multi-million pound funding would be required.

“We very much believe that the practical geo-engineering that we are proposing should be implemented and could be very much part of our landscape within the next 10 to 20 years”, Dr Fox concluded.

See also:

Climate Change Geoengineering Could Cause Droughts

Approval for Climate Change Geoengineering Research