we need to start by being honest about the overwhelming impacts humanity is already having on the Earth system
Green groups reacted with astonished anger earlier this month to news that the Intergovernmental Panel on Climate Change (IPCC) had convened a geoengineering expert group meeting in Lima to propose radical solutions to the climate crisis.
More than 160 environmental groups wrote an open letter to the IPCC decrying what appeared to be a tacit acceptance that manipulation of the natural environment had some part to play in dealing with runaway climate change.
Geoengineering schemes include dumping iron filings into oceans to foster growth of carbon-sequestering algae, blasting mirrors or sulphur dioxide particles into space to deflect sunlight and genetically modifying crops to be whiter and so reflect more heat.
And yet with global carbon emissions increasing, political consensus on mitigation more intractable an issue than ever and unregulated forays into climate manipulation already underway (Richard Branson has endorsed atmospheric carbon-stripping, Bill Gates cloud-whitening), many now concede that environmentalists too will have to come to some accommodation with geoengineering.
Critics counter that no quick-fix solution to climate change exists and may never exist. Meddling further with the environment, they say, will have manifold unforeseen, far-reaching and possibly catastrophic effects. The geoengineering cure, in short, may end up killing the patient.
Is it plan A or B?
The most authoritative paper on the subject, a 2009 report by the Royal Society, concluded that emissions reduction should be the priority of government. Geoengineering was still plan b.
Geoengineering’s two main tranches –solar-radiation management (SRM: deflecting the sun’s rays to cool the earth) and techniques for removing carbon dioxide from the air – should ‘only be considered as part of a wide package of options for addressing climate change’.
However, Mike Childs, Friends of the Earth’s head of climate change, says there is an acceptance among many scientists and ‘a good number’ of NGOs that some lower-risk measures need to be deployed as soon as they can be developed and robust governance is in place – negative emissions technologies like air capture of carbon and storage; measures with an off switch.
‘If it’s possible to deploy these things and stop them if things are going wrong then it’s possible to proceed with more comfort. If they have no way of being stopped easily and risk spiralling out of control, then clearly you have to proceed with extreme caution.’
Criticised for his high-profile conversion to nuclear energy, activist and author Mark Lynas hopes that geoengineering ‘can perhaps be considered a little more rationally’ by greens since it comes with ‘less historical baggage’.
He distinguishes between ‘unintelligent’ geoengineering – polluting the world’s atmosphere – and taking a strategic approach to managing the world properly according to the ‘planetary boundaries’ defined by international science.
‘This may or may not involve direct climatic interventions like putting sulphates in the stratosphere, but we need to start by being honest with ourselves about the overwhelming impacts humanity is already having on the Earth system.’
Mike Childs stresses that no geoengineering project is a magic bullet that will allow the world to continue destroying the environment, but adds: ‘The distance between what scientists say is necessary to try to prevent worst of climate change and what politicians are willing to do is so enormous; you can’t see it being closed fully. But some geoengineering projects – along with extra effort on mitigation – could help close some of that gap.’
Nor is any project as safe and as cost-effective as cutting emissions – and cheap geoengineering measures are assuredly not an option. SRM techniques – including creating clouds or using mirrors to regulate energy from the sun – were panned last year by researchers from Carnegie Mellon and Oxford universities, as well as the UK’s parliamentary Science and Technology Committee (STC), which suggested implementation in one area could severely impact on others, through drought or altered precipitation, and potentially lead to national conflict.
'Foolish' to ignore geoengineering
And yet the STC concluded it would be ‘foolish’ to ignore the potential of geoengineering to reduce or reverse the effects of climate change, provided it was an inclusive project: it recommended UN regulation to prevent countries taking unilateral action.
Marine experts too have also been feeling their way towards a more supportive position. Ways of stripping carbon from the atmosphere had to be urgently researched, a report from the International Programme on the State of the Ocean (IPSO) concluded last month, if dangerously high levels of sea acidification are not to result in mass extinctions. It specifically ruled out iron fertilisation, however, which would lead to more carbon dioxide entering the oceans.
Philip Boyd, a phytoplankton ecologist from New Zealand’s University of Otago, has written a paper ranking geoengineering schemes according to efficacy, cost, risk and rate of mitigation.
He takes a pragmatic view, acknowledging the proliferating number of schemes being mooted in the popular press, but says the green lobby must decide whether researching geoengineering measures is to tacitly approve them – as many perceive the IPCC to have done.
He stops short of condoning any dabbling in the marine environment.
‘All carbon-dioxide removal schemes could potentially knock over sea acidification,’ he says, ‘but they need to be much more fully investigated.’
Is it a distraction?
Atmospheric scientist Ken Caldeira, a world authority on geoengineering from the Stanford Carnegie department of global ecology and a keynote speaker at the IPCC expert meeting in Lima, suggests that geoengineering is already being taken too seriously.
Rather than governments or green groups issuing strong statements of support or condemnation, he recommends adopting a ‘wait and see’ attitude – except where it comes to transforming the world’s energy system into ‘one that does not use the atmosphere as a waste dump’.
‘At this stage ideas of reflecting sunlight away from the Earth to offset greenhouse-gas heating of the planet are appropriate subjects of investigation for climate scientists. But while there is some chance that such approaches could reduce climate risk, and in some circumstances climate damage, they add all kinds of new risk. It is premature to consider sunshade-geoengineering a viable policy option that should be advocated or condemned.’
Teresa Anderson of the Gaia Foundation, a signatory to the IPCC open letter, says there are no geoengineering techniques that aren’t ‘entirely counterproductive in terms of their socioeconomic and environmental impact, and/or completely nuts’.
Environmentalists engaging in the geoengineering debate risk being distracted from the urgent task at hand.
‘Like carbon capture and storage (CCS), these technologies are not there and may never be. They are distant hopes of an unworkable Plan B that are allowing governments to get out of the imperative action they need to take right now.’
Problem, solution, problem...
The solution: volcano replication – injecting sulphur dioxide into the stratosphere, where it reacts to become sulphate aerosol particles that absorb or reflect sunlight
The problem: potential depletion of ozone layer, acid rain, adverse effect on plant photosynthesis
The solution: reflective particles spread on the ocean, as mooted in a 1965 environmental report from US president Lyndon Johnson’s science advisory committee.
The problem: ocean pollution, damage to sea life
The solution: iron fertilisation – dumping iron filings into the sea to promote carbon-sequestering algal blooms and reduce ocean acidification
The problem: algae consumed by other organisms, returning carbon dioxide back to atmosphere
The solution: cloud-whitening – spraying seawater into clouds to increase cloud albedo (reflectance)
The problem: unknown side-effects, including changes to weather patterns and ocean currents
The solution: mirrors in space to deflect sunlight
The problem: expensive and energy-intensive, space debris, difficult to control, would not address ocean acidification
The solution: artificial trees – sucking carbon from the air and sequestering it
The problem: untested carbon-storage technologies, requires energy to power process
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