By now we've all heard that carbon dioxide is the main culprit behind global warming and that the burning of fossil fuels is the biggest contributing factor to the rise of CO2 in the atmosphere. Reducing our use of fossil fuels has been at the forefront of the fight to combat climate change. The symbols of the green movement—fuel efficient cars, wind turbines, CFL bulbs—are all methods of lowering our carbon footprint.
But some engineers in the UK have been looking at other approaches to the problem. A new report from the Institution of Mechanical Engineers, titled "Geo-engineering: Giving Us the Time to Act?" proposes three plausible technological approaches:
1. Artificial trees
Trees naturally absorb CO2 from the air through photosynthesis and sequester it. Now researchers are looking into the possibility of sequestering CO2 with machines that will do the same thing. Air will pass through the machine and the CO2 will stick to a sorbent material, which is then removed and buried underground.
2. Algae-coated buildings
Like trees, algae also sequesters CO2 through photosynthesis. According to the report, strips of algae can be fitted to the outside of buildings, turning the building into a giant carbon magnet. The algae can then be harvested for biofuel.
3. Reflective buildings
CO2 traps heat from the sun, warming the earth so reducing the amount of CO2 reduces the amount of trapped heat. But what if we could reduce the amount of heat coming in? The report suggests increasing the number of reflective surfaces on earth, starting with reflective rooftops, and bouncing solar radiation back out towards space.
The report's authors state that geo-engineering is not a silver-bullet that will put an end to global warming, but that these techniques can be an important tool in slowing climate change. The technologies proposed can be used in the short term to buy precious time while we figure out how to reduce our dependance on fossil fuel, and lower the amount of CO2 that we are pumping into the air.