Emission control

The notion of global warming was first mooted by French scientist and mathematician Joseph Fourier in 1824 and discovered by John Tyndall in 1860, he and later, Svante Arrhenius, pinned down the mechanisms. It is perhaps deceived wisdom that Arrhenius was the first to suggest that Sweden might once again be able to grow tropical fruit, such as bananas with a little geo-engineering, but Alexander Graham Bell in 1917 suggested that the unchecked burning of fossil fuels would force the very greenhouse effect and global warming we have observed since the Industrial Revolution. The data is there, despite the denialists and those who suggest the infrared spectrum of carbon dioxide is not enough to cause the effect and that atmospheric water vapour is the only relevant factor. I recently wrote of a decade’s worth of evidence that demonstrates once and for all that carbon dioxide is the forcing factor.

That notion of geo-engineering has been discussed at length in recent years, looking at ways of scrubbing out the carbon from polluters such as cars and fossil fuel power stations, sequestration of the gas from the atmosphere, anything to avoid having to actually do anything to reduce our reliance on fossil fuels or to actually cut emissions or offend the oil companies. It seems unlikely that we will give up our power any time soon even in the face of climate change. It could be that carbon sequestration is the only way forward.

Now, scientists in India have modelled the effect of physically removing carbon dioxide from the air. Their non-linear model takes into account particulates, water droplets and many other factors.

The team has applied their model to two possible scenarios. In the first, they assume that carbon dioxide would be removed from the atmosphere through the introduction of aerosols or particulates (calcium oxide) that would sequester carbon dioxide so that it would precipitate out of the atmosphere. The model suggests that greenhouse gases could be eliminated from the atmosphere using this approach. In the second scenario, absorption of carbon dioxide would be carried out by plant photosynthesising species.

Of course the feasibility of such geo-engineering relies on a carbon neutral technology for their implementation and the means to dispose of the precipitate in the first scenario and a sustainable use for the biomass that doesn’t simple regurgitate the greenhouse gas back into the atmosphere through decay or burning.

Shukla, J.B., Chauhan, M.S., Sundar, S. and Naresh, R. (2015) ‘Removal of carbon dioxide from the atmosphere to reduce global warming: a modelling study’, Int. J. Global Warming, Vol. 7, No. 2, pp.270–292.

Author: David Bradley

Award-winning, freelance science writer based in Cambridge, England.