Memorandum 163
Submission from the Royal Society
1. Geoengineering of the climate covers
a wide range of schemes and technologies. At present there is
no single definition that is universally accepted, although it
typically refers to any large scale intervention or manipulation
of the earth's climate system. Schemes can be categorised in two
forms:
2. Blocking or filtering sunlight. For example,
through dispersing sulphates in the atmosphere, cloud seeding,
or space-based mirrors.
3. Removal of CO2 from the atmosphere. For
example by promoting algae blooms to increase oceanic carbon uptake
(by fertilisation with iron or urea, or through tubes circulating
deep ocean water); capturing of CO2 directly from the air or at
the point of emission (as in carbon capture and storage); promoting
carbon sequestration by terrestrial biological processes such
as forestation, avoided deforestation and changes in agricultural
practices.
4. Apart from point source carbon capture
and storage, forestation and agriculture projects, most of the
schemes are still conceptual and need considerable research and
development to understand the effectiveness of these various technologies
as well as the feasibility. It remains unknown whether any of
these proposed schemes will ever offer any viable solution to
climate change. Research will also be needed to understand and
evaluate the potential wider environmental and social impacts
of these technologies and the risk of unintended consequences.
The diversity of issues and schemes will mean a wide range of
expertise including scientists, engineers, social scientists and
economists, across a number of disciplines, will be required.
5. Potential options for large scale engineering
of the climate are slowly gaining prominence, both in the media
and in parts of Government. The motivation for developing these
schemes is driven by concerns about the continuing rise in atmospheric
concentrations of greenhouse gases and the inadequate global response
to cutting emissions. Furthermore, commercial interests are promoting
some of these projects, driven by the potential to develop credits
in a carbon market.
6. At this stage, with such a wide range
of potential technologies and options, many of which are only
concepts, too little is known to be prescriptive about the role
of engineering in the development of geoengineering. This lack
of knowledge about the potential of the various schemes means
it is too early to make any assumptions about how they will interact
with other responses to climate change.
7. Regulation will be needed for each of
these various technologies and, more immediately, of the research
needed to develop them. Decisions on research and development
must be informed by the best available science and engineering
to minimise the risks of unwanted or unintended environmental
and social impacts. Uncertainties about the potential for these
impacts have already led some international bodies, such as the
Convention on Biological Diversity, to raise concerns about the
development of geoengineering technologies.
8. In response to this lack of reliable
information on the topic, the Royal Society will be launching
a major study of large scale climate engineering in October/November
2008. The working group, which will include scientists and engineers,
will investigate the potential, feasibility and drawbacks of suggested
geoengineering techniques. Consideration will also be given to
the kind of regulatory framework that will be needed for the development
of these technologies.
October 2008
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