GEOENGINEERING – THE PRICE WE MAY HAVE TO PAY?

Engineering Earth 'is feasible'
Pallab Ghosh, 1 September 2009 (BBC News)

["...Geoengineering the climate: Science, governance and uncertainty, from the UK Royal Society, reports]…that many engineering proposals to reduce the impact of climate change are "technically possible"…could be effective…[but] should not divert governments away from their efforts to reduce carbon emissions.

"Suggestions range from having giant mirrors in space [to reflect the Sun's rays away] to erecting giant CO2 scrubbers that would [remove carbon dioxide and] "clean" the air…Ambitious as these schemes seem, the report concluded that many of them potentially had merit, and research into them should be pursued…[but it stated] some of the technology was barely formed and there were [uncertainties about effectiveness, costs and impacts]…One of the technologies…pouring iron filings into the ocean to grow algae…[is too risky and could substantially harm] marine life and freshwater, estuary and coastal ecosystems…"

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"The study stressed that engineering approaches would only have a limited impact, and that efforts should continue to be focused on reducing CO2 emissions…But [called for more]…research and development…[to discover what] low-risk methods can be made available if it becomes necessary…Of the two basic geo-engineering approaches…those involving the removal of carbon dioxide were preferable…[but] too expensive to implement widely…[and work too slowly to be effective]…This included "carbon capture and storage" methods…Of the carbon removal techniques assessed, three were considered to have most potential…1. CO2 capture from ambient air…2. Enhanced weathering…3. Land use and afforestation…

"…[S]olar radiation management methods do not take carbon dioxide out of the atmosphere…[and] may be ineffective in altering shifts in rainfall patterns and storms…[But] could be a faster way to reduce the rate of increase in global temperatures…[S]uggestions include: a giant mirror on the Moon; a space parasol made of superfine aluminium mesh; and a swarm of 10 trillion small mirrors launched into space one million at a time every minute for the next 30 years…[T]hese approaches [make] huge logistical demands…[and could take several decades] to be implemented…But if temperatures rose to such a level where more rapid action needed to be taken, three techniques were considered to have most potential…1. Stratospheric aerosols…2. Space-based methods…3. Cloud albedo approaches…"

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"The report also highlighted an inadequate international legal framework for cross border projects…[and] urged an appropriate international body, such as the UN Commission for Sustainable Development, to establish a method for developing treaties to determine who would be responsible for research that might have global risks and benefits…"

[Professor John Shepherd, researcher, the University of Southampton and Chair of the Royal Society geo-engineering study:] "It is an unpalatable truth that unless we can succeed in greatly reducing CO2 emissions, we are headed for a very uncomfortable and challenging climate future…Geo-engineering and its consequences are the price we may have to pay for failure to act on climate change."