Humans are engineers, even the artists. We humans engineer the surface of the globe; we change the Earth’s climate; and we drive other species into extinction. We do not do this on purpose. It is by-product of our sheer number and the way how we function as society. However, recently we got worried, at least a bit and some of us. We may got it wrong. Our way of living, producing or consuming does not look sustainable for long.
The same kind of policy also was successful on more regional scales. Regulated reduction of sulphur emissions reduced acid rain. Banning of certain pesticides saved birds from extinction. Thus a general experience formed. Regulations to reduce pollution at the sources showed to be a successful policy to improve living conditions. These regulations could be negotiated when they could be combined with a reasonably cheap technology. The intended shift of technology got economically feasible.
|Image Credit: http://www.pbs.org/wgbh/pages/frontline/heat/art/graph3.jpg|
Nowadays we face anthropogenic climate change, because of the massive carbon dioxide emissions from burning coal, gas and oil. In view of human experiences it seems obvious to apply the known mix of regulation and engineering to reduce anthropogenic climate change. Just as air pollution that was causing acid rains has been reduced by cleaner combustion processes; or such as ozone destructing chemical coolants have been replaced by other substances. The common approaches of these and other success-stories were to reduce threat to global or regional earth systems by withholding emission, replacing substances or limiting their use cases. Thus, the successful approach was a technological fix combined with a regulatory measure both targeting the “start of the pipe”.
Unfortunately, targeting mitigation of anthropogenic climate change is more difficult. Applying a “start of the pipe” approach to climate change faces the issue that mankind should reduce inputs where its hurts, namely reducing much the amount of energy that is produced from burning fossil fuels. However, capping burning of fossil fuels would be disruptive for the economic structures or the consumption pattern of many developed and developing industrialised societies. Replacing fossil fuels with other energy sources seem to be difficult, for technical and economic reasons ; notwithstanding "unfavourable power-plays". On the other hand, striving towards “global sustainability” through lesser use of energy would require drastically adjusting the current production and consumption patterns at a global scale. Achieving that seems to be beyond human political skills.
Facing that dilemma, affordable geoengineering looks tempting for some. Contrary to an approach of global sustainability through lesser use of energy, “geoengineering” deploys a “technology fix” to mitigate anthropogenic climate change. The fix aims to modify the earth’s climate system. The modification shall offset the stronger greenhouse effect that is caused by the increased carbon dioxide concentration in the atmosphere. Thus the question arises, whether humans may endeavour to engineer the Earth to counter climate change hazards when they are facing the dilemma that they are not able "to reduce radically energy that is produced from burning fossil fuels"?
|from bellaeacot.worldpress.com [**]|
However the geoengineering technologies that counter climate change by other means than carbon capture at combustion are of a particular nature. They differ from the technological fixes that, combined with negotiated regulatory actions previously have been applied to limit threats to regional and global systems. Most of the proposed geoengineering technologies target other parts of the climate system but the carbon-dioxide input into the atmosphere.
These technologies do not work at the “start of the pipe”. Instead they address either the "end of the pipe", such as re-forestation or ocean-fertilizing technologies or they tackle other parts of the climate system, such as reducing incoming solar radiation through particle injection into the higher atmosphere. Therefore, these geoengineering technologies differ qualitatively from the known success stories of human mitigation of anthropogenic environmental threats. Should these technologies be part of the toolbox to tackle anthropogenic climate change? Should these technologies be perceived referring to their qualitative difference?
“The acceptability of geoengineering will be determined as much by social, legal and political issues as by scientific and technical factors” , conclude Adam Corner and Nick Pidgeon (2010) when reviewing social and ethical implications of geoengineering the climate. In this context of “acceptability” It is to debate that most geoengineering technologies are “end of the pipe technologies”, what involves an additional risk.
|from Space Daily [*]|
[*] http://www.spacedaily.com/reports /2012_Antarctic_Ozone_Hole_Second_Smallest_in_20_Years_999.html
 It seems that carbon capture at power plant would increase production cost increase by 1.5-3.0 $c/kWh excluding cost of transportation and storage (Jeremy David and Howard Herzog, Massachusetts Institute of technology (MIT), Cambridge, MA USA, 6pp. http://sequestration.mit.edu/pdf/David_and_Herzog.pdf)
 Adam Corner and Nick Pidgeon 2010, Geoengineering the climate: The social and ethical implications, Environment Vol. 52.