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

So CCS isn't perfect either?!

Like many things in life, a world of safe CCS may be too good to be true.

Carbon capture specialist Udayan Singh highlights the key problem areas for CCS: the safe transportation of CO₂ and precise and secure injections of CO₂ into geological formations. If this method is to be introduced there will be great pressure on the quality and constant maintenance of carbon pipelines and injection, as leaks could cause vast environmental damage and would prove very costly.

The devastation of the Lake Nyos disaster
http://www.emigennis.com/2014/04/06/lake-nyos-disaster-reference-photos/

Forgarty & McCally state that if CO₂ concentrations were to reach 7%, enough carbon would be present in the blood of humans to cause narcosis and eventually asphyxiation. To support their points, they offer the Lake Nyos, Cameroon 1986 case study. 100,000 tonnes of CO₂ was released as an overturn of a volcanic lake (near Lake Nyo, as described by Damel et al) as the bottom part became over saturated with CO­₂, Holloway importantly claimed that this was due to a slow leak of CO₂ from magmatic sources into the lake. The leak resulted in  carbon concentrations of up to 10% in surrounding areas and consequentially over 1700 people died whilst hundreds contracted skin conditions or suffered from memory loss. This volume of CO₂ equates to seven days of CO₂ emissions from a single coal-fired power plant, and shows just how catastrophically dangerous this technique may have the potential to be. Pro-CCS scientists argue that this singular event cannot form the basis for summarising the risks associated with CO₂ leakage from a geological formation, however, as CO₂ is heavier than surrounding air it accumulates readily in depressions such as lakes. Therefore I believe that this case study does provide strong and accountable evidence for the dangers faced by carbon capture, and it insists that serious considerations need to be introduced before CCS is implemented worldwide.

Additionally, another potentially severe environmental risk caused by CCS is the potential for ocean acidification caused by leaked CO­₂. Ocean acidification is caused by carbon dioxide reacting with the ocean to create carbonic acid (CO₂ + H₂O à H₂CO₃). The ocean represents the planets largest carbon sink, an increase in carbonic acid severely threatens carbonate secreting organisms in the ocean and in doing so reduces the oceans capacity for carbon storage and so more CO₂ is released into the atmosphere and in doing so worsening the greenhouse effect. 

Moreover, Forgarty & McCally point out that ocean acidification can cause an increase of contaminant (e.g. Arsenic and lead) leaching which would endanger the lives of countless species. Furthermore, Holloway (1996) argues that as well as oceans, groundwater located (100-200m below the surface) may be contaminated from CO_2­ leakage. CO₂ groundwater contamination may cause increases in water hardness as well as transforming the concentrations of trace elements present in the water and therefore has seriously negative effects on our drinking water aquifers.

Finally, there is much discussion within the scientific regarding induced seismicity caused by the injection of CO₂ into the ground. Environmental scientists Verdon & Stork state that large volumes of CO₂ injected into a geological reservoir increases the pore pressure of the reservoir rock, which increases the chance of rock failure. Holloway importantly argues that this could result in micro-seismicity or activating previous faults which may trigger earth tremors. Seismic events within reservoirs could damage cap rocks, natural springs or open up faults allowing for CO₂ leakage further damages to other parts of the environment, environmental effects described above can impact the plant. 

Through my research into the risks associated with CCS, it is absolutely clear that this climate mitigation method is not perfect, and requires serious evaluation as to whether these risks can be limited or if the method is even viable at all in sight of these concerns. Luckily for you, I’ll be doing this in my next blog post!

The great potential of Carbon Capture & Storage

Carbon emissions reductions

This year, British home secretary Amber Rudd committed the UK to the ‘fifth carbon budget’, which binds the nation to a maximum CO₂ output between the years 2028-2032 of 1,725 MtCO₂e. Currently, it is thought by many that the UK will not meet this target without substantial changes to energy policy. CCS has a potential to account for 17% of necessary the nations carbon emissions reductions, and so would offer great support for the British energy industry as it may mean that there wouldn’t be a need for such a rapid switch to renewable energies which would inevitably be very costly.

Storage potential

There appears to be a vast storage potential for CO₂ within the Earth, but due to the numerous types of geological formations, the planet’s potential is difficult to estimate. Scientist Udayan Singh reports on IPCC suggestions that there may be the opportunity to store 2000Gt of CO₂ within the planets formations. Further investigations into this reveal that between 675-900 Gt of CO₂ could be stored into oil and gas fields, 1000-10,000 Gt of CO_2­ may be contained in saline formations and between 3-200 Gt of CO­₂ within coal beds. Udayan Singh importantly points out that in 2010, annual global CO₂ emissions were less than 34 Gt of CO₂, thus clearly demonstrating that the world can take confidence in this environmental policy. In addition it is also important to note that as our fossil fuel consumption increases, more space in geological formations for CO₂ storage will become readily available.

Key carbon storage examples:  UK & India case studies

In terms of the UK’s personal environmental policy, Jon Gibbins and Hannah Chalmers predict the UK offshore CO₂ storage potential to be at least 20 Gt of CO₂. This type of formation alone could store the UK’s CO₂ emissions for 40 years!

Fig. 1 - A geological map of India, showing the presence of basaltic rocks
as well as highlighting regions of good, limited or fair storage potential
https://hub.globalccsinstitute.com/publications/regional-assessment-potential-co2-storage-indian-subcontinent/22-potential-geological

Researchers Udayan Singh also reveals information regarding the storage potential of India (the world’s third largest CO₂ producer) and combined their research with McGrail et al’s laboratory experiments to conclude that India alone has an incredible potential for CO₂ storage within onshore and offshore saline aquifers (360 Gt) and within Basaltic rock settings (200 Gt). McGrail et al’s tests revealed that the basalts within the region showed fast chemical reactions with CO₂-saturated water, enabling it to produce stable carbonate minerals. When analysing fig 1, one can realise that due to the vast quantities of basaltic rock within India (formed as a result of the Deccan Traps eruptions which produced material that covers 500,000km² of India’s Western provinces), India’s storage potential within this type of geological formation, and future potential after further scientific research into this field is immense.

Another advantage which would result from storing CO₂ within depleted oil and gas fields is that it will allow for the  recovery of further oil and gas that was not initially recovered for a variety of reasons, for example because it was not initially economically viable. CO₂ also has many industrial purposes, and is used in pharmaceutical, fertilizer and beverage carbonation industries (Udayan Singh).

These methods provide further advantages, as pumping CO₂ into oil fields can also help to retrieve more fuels that were not recovered during initial oil exploration. This is due to the fact that CO₂  injection reduces the viscosity of oil, thus improving the ability of oil  to flow up boreholes to the surface.Whilst in basalt formations, CO₂ reacts with the basalt to form carbonate minerals, further adding to the stability of the formation.

Economic incentives

An interesting economic incentive to carbon capturing is the emission trading mechanism, which limits a country to a maximum volume of CO₂ that can be emitted. However if a country to reduce its emissions below the maximum amount, they would be able to use the CO₂ as a commodity which they could then use in trading and thus generate profits from. This offers yet another advantage for Less Economically Developed Countries, who may not otherwise prioritise emission reductions due to their respective financial situations.

Furthermore, the UK government reports that should CCS be fully implemented into power plants that produce electricity for domestic use, energy prices for citizens would decrease by up to £0.02 per Kilowatt hour (Kwh) by 2030 (fig.2). Correlating this to the whole UK population would show significant energy savings nationally. 

Fig. 2 - A chart expressing future energy savings (in pence per Kwh) per year
with CCS implementation.
https://www.tuc.org.uk/sites/default/files/carboncapturebenefits.pdf

Therefore one can conclude by realising that there is a great potential for CCS, with positive practical and economic aspects, what now needs to be decided is whether these positives outweigh negative issues, which will be talked about in the next blog post.