By Joseph Milton, FT science intern

Simulations run by a team at the University of Bristol suggest that the melting of the Greenland ice sheet could be prevented by reflecting sunlight from the earth’s surface, a geoengineering technique.

Geoengineering offers radical solutions to climate change, involving large-scale alterations to the environment, directly affecting the climate. Discussion of these potentially risky procedures is increasingly common as many scientists reach the conclusion that CO2 emission reduction targets are not being met, and are unlikely to be. The Royal Society recently invited a panel of scientists to look into the subject and produce a report: Geoengineering the climate: science, governance and uncertainty.

The research at Bristol, led by Peter Irvine and published today in Environmental Research Letters, found that the temperature of the planet could be reduced to pre-industrial levels, saving the ice sheet, by reflecting 4.2 per cent of incident sunlight back into space.

But reflecting such a high percentage of sunlight, while doing nothing to reduce atmospheric CO2 levels, could reduce rainfall and change weather patterns, so the team also investigated reflecting 2.5 per cent of sunlight. They found this reduced the undesired side effects, but still cooled the planet enough to avoid the collapse of the ice sheet.

The Bristol team suggest sunlight could be deflected using geoengineering techniques known as solar radiation management. One option is the use of space reflectors – trillions of tiny reflective particles at the Lagrange point, the point in space at which the Earth and the Sun’s gravitational fields cancel each other out.

Professor Peter Cox at the University of Reading, who worked on the Royal Society report, says it might work: “It would be like just turning the sun down a bit.” But obviously there are technical considerations. As Professor Joanna Haigh of Imperial College, another of the report’s authors, points out: “The costs and the timescales involved would be absolutely enormous.” Neither thinks this technique is feasible in the near future.

Another option suggested by the Bristol team involves the addition of sulphate particles to the atmosphere, where they would reflect solar radiation. Prof. Cox says this is more difficult to rule out than he had imagined before the report was written, but Prof. Haigh is less convinced: “Who knows what the knock-on effects would be?” she says.

Solar radiation management is one of two broad categories of geoengineering techniques. The second is carbon dioxide removal, recently suggested as a possible complement to mitigation actions by Rajendra Pachauri, head of the Intergovernmental Panel on Climate Change.

Removing CO2 from the atmosphere would be a better long-term solution to global warming, as it would tackle not just global temperatures but other problems associated with high levels of greenhouse gases too, such as ocean acidification. But it would be very slow to affect the climate. On the other hand, the effects of reflecting sunlight could be seen within a few years.

Peter Irvine stressed that geoengineering should only be regarded as an emergency response: “It is no substitute for reductions in the emission of CO2,” he said.

Clive Cookson

Synthetic biology is one of those futuristic concepts, like nanotechnology and regenerative medicine, which everyone feels is going to be a key technology for the 21st century but few really understand. All are a bit fuzzy in their definition – and practitioners are not clear about how much they are already happening and how much they lie in the future.

In effect, synthetic biology takes genetic engineering beyond the insertion or manipulation of individual genes, which scientists have been doing for 30 years. The idea is to engineer large numbers of genes at the same time to transform micro-organisms – and potentially even create new organisms from scratch – in ways that enable them for example to make previously inaccessible drugs or biofuels.

Britain’s Royal Academy of Engineering draws attention to the potential of synthetic biology in an excellent new report this week. Its message is that a national strategy of research and training in synthetic biology is essential, if the country is not to lose out in the next industrial revolution in the life sciences.

“The UK missed out in the 1970s microchip revolution because the government and decision-makers were not fully informed by experts in the field about its potential,” said Richard Kitney of Imperial College London, lead author of the RAE report, at its launch at the Science Media Centre. “Synthetic biology is destined to become of critical importance to building the nation’s wealth.”

Beyond the UK-oriented call to arms, the report is a good summary of who is doing what in synthetic biology.

The fact that an engineering body has written a report about biology may seem surprising at first – but it turns out that one of the key features of the new field is the application of rigorous engineering principles to the design of biological systems. Moving on from gene replacement on a case-by-case basis, biological engineers are developing standard procedures for designing, modelling, testing and validating methods to make and use synthetic DNA.

No-one will be surprised to learn that the US is well ahead of the rest of the world in both the basic science and the early commercialisation of synthetic biology. The RAE report lists 18 companies active in synthetic biology, of which 14 are based in the US.

Prominent American researchers include Craig Venter, the genomics pioneer, who is on the verge of building a simple microbe from scratch using laboratory chemicals, and Jay Keasling of the University of California Berkeley, who has engineered yeast to make artemisinin, the anti-malarial drug currently extracted from wormwood plants.

The world of research

The science blog is no longer updated but it remains open as an archive.

Clive Cookson, the FT's science editor, picks out the research that everyone should know about, in fields from astronomy to zoology. He also discusses key policy issues, from R&D funding to science education. He'll cover the weird and wonderful, as well as the serious side of science.