Geoengineering conspiracies Top Trumps continued...

Algae covered buildings: Algae on buildings could be implemented to actively take up CO2 from the atmosphere. Although it may not be majorly effective, it is worth a thought!

Vertical farming: Food production will allow for the production of crops to meet the planets growing food demand, without the requirement for deforestation as less land would be required for food production.

Artificial trees: Artificial trees would capture CO2 from road sides and secreting them into carbon storage facilities. Although this option would not have a major environmental impact, it may be faily cost effective and is quite a realistic option as the artificial trees could be produced from similar environmental concepts currently out there. 

Geoengineering conspiracies Top Trumps

This and the following blog post will attempt to address some of the crazy and borderline conspiracy geoengineering theories that are to be found from all corners of the web, evaluated in a ‘top-trump’ style review of each engineering method, because, well, why not? Each technique will by rated out of 100 points based on its ability to save the planet, it's cost-effectiveness, it's negative impacts and a realism rating - a higher rating being beneficial for each focus.

Ocean Fertilisation: The dumping of nutrients (e.g. Dust Fe) as a carbon removal option with the intention of this increasing productivity amongst microscopic phytoplankton in the oceans thus increasing the oceans carbon uptake.  

Dam the Med: Introducing a dam in the Mediterranean ocean, which could allow warmer water to circulate towards Canada creating increased snowfall and expanding Canada's diminishing Ice sheets.

Flood Death Valley: Flooding below sea-level Death Valley, and other similar localities could help fight rising sea levels

Wrapping Greenland in reflective blankets: Suggested by glacier expert Dr. Jason Box, wrapping Greenland in a reflective blanket would attempt t reflect more of the sun's energy back into space, thus reducing surface temperatures, allowing for greater control of the Earth's Albedo. 

Hmmm.

Giant Space Mirrors...Science-Fiction or Science-Fantastic?

Generic sci-fi poster

Giant space mirrors. They sound like something out of the latest 'end of the world' sci-fi film that will inevitably collide with an asteroid, sending the object hurtling towards Earth to threaten humanities very existence. 

At least, that's what you'd think...

In 2001, American climate scientist Lowell Wood proposed the insertion of ‘giant space mirrors’ into space to the United States government as a strategy to protect Earth from the worsening impacts of climate change. A giant space mirror would attempt to reduce the solar energy the Earth receives by reflecting solar rays back out to space. It is thought that a space mirror system could weaken global insolation from the solar rays at a rate of 1 W m^-2 per decade. This would increase the Earth’s albedo effect whilst balancing out the impact radiative impact of the planet’s ever increasing greenhouse gas emissions.

A theoretical idea of what a space mirror could look like
http://www.nerc.ac.uk/planetearth/stories/302/

Could it help?

The principle reason for the use of space mirrors is that it could have a very positive effect of limiting sea-level rise. Over 634 million people around the world live in an area of low elevation, including 46% of the population of Bangladesh who live within 10m of sea level. Thus, any impact that a geoengineering scheme can have on limiting sea-level rise may be of undeniable assistance to millions on our planet. 

Is it viable?

When assessing the practicality of this notion, one can quickly realise that the insertion of giant space mirrors is flawed. Firstly, Lowell Wood’s proposed space mirror requires a surface area of 600,000 miles². That's over twice the size of the state of Texas! This staggering assessment then leads to the thought of how costly space mirrors may be. The economic viewpoint is examined well by Takanobu Kosugi. His estimates vary depending on how much the planet would need to be cooled by. By 3ᵒC, costs my exceed $240 billion, however by 6ᵒC costs may be up to $1.9 trillion. Kosugi bases these figures too on the fact that mass production of required space parts would lead to reduced costs, a thought that carries no certainty.

To conclude, although it must be admitted that space mirrors would reduce global temperatures, at a cost of $1.9 trillion, they are certainly not a viable option as they do not address other key climate issues such as ocean acidification. Therefore it is with regret that I must label this geoengineering theory as nothing more than a good bit of science-fiction. 

Carbon Capture...Is it a YES or NO?

In the past two weeks, I have posted blog updates arguing critical points in favour (The great potential of Carbon Capture & Storage) of implementing Carbon Capture and Storage (CCS) as well as arguments against (So CCS isn't perfect either?!) this technology form. Here I shall attempt to evaluate the opposing arguments to determine whether this method of geoengineering is a realistic and viable option to tackle the threats posed by climate change.

Firstly, in terms of mere practicality aspect, there can be an excuse for...dare we say it...optimism. The storage potential for CO₂ within accessible geological formations undoubtedly impressive. Jon Gibbins and Hannah Chalmers' work alone which argues that the UK could use this technology to store forty years’ worth of carbon emissions is worthy of governments offering their attention to this concept. When examining this idea, one must also analyse the environmental risks offered by this method to determine whether this advantage is actually worth it at all.

As outlined in 'So CCS isn't perfect either?!', the threats to the environment through ways such as: CO₂ leaking at the surface and creating a risk of asphyxiation amongst those living close to the source, CO₂ leaking into oceans contributing to the production of carbonic acid further enhancing ocean acidification and the contamination of vital groundwater sources that are used to provide fresh drinking water for many. Therefore if we are to proceed with CCS, I believe that a certain criteria should be met to avoid or at the very least minimalise negative environmental impacts that may be caused. Firstly, the materials used to create transport pipelines and storage facilities must be of the highest quality and be constantly analysed for any potential re-occurring maintenance issues. Storage at onshore localities should be very limited, areas that contain diverse ecosystems should be totally avoided. I also believe there should be further collaboration between researchers, industrial companies and policy-makers to ensure that further testing of limiting CO₂ can be done before any amount of carbon is to be stored beneath the sea. If these points met, then CCS may be a viable option.

However, in refutation of the previous argument, to meet this criteria would impose an even greater financial burden for this technology. It is predicted that per tonne of Carbon removed, the cost would be €60-90, which when taking into account the megatons of carbon that would be abated represents a severe economic investment. Such an investment would no doubt require government subsidies to attract companies to undertake CCS.

Is at all worth it? Are we better suited investing or subsidizing ‘greener’ technologies?



To conclude, I believe that CCS is by no means a perfect solution, and requires further development and investment to ensure it would not hinder environmental processes. However, one must realise that currently (as of 29^th November) CO₂ concentration in the atmosphere is at 403.84ppm, the highest concentration of CO₂ in the atmosphere for 650,000 years. It is also clear that as a society, there will not be a decline in fossil fuel use for considerable time. Taking these thoughts into account I believe that there is hope for CCS as a policy. I’d like to point out the ‘Carbon bathtub’ analogy (fig.1). This analogy allows us to identify that even if we were to cut carbon emissions right now, we still have an atmospheric CO₂ and so we require at least some form of removing current CO₂ from the atmosphere. At this current point, a further enhanced CCS method may be a positive option.  





Fig.1 http://ngm.nationalgeographic.com/big-idea/05/carbon-bath