4 | NewScientist | 7 April 2012

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SOME schemes to save the Earth just might cost the Earth. Back-of-the-envelope calculations suggest that scaling up proposals to scrub the atmosphere of carbon dioxide would mean creating the biggest industry there has ever been.

You can strip CO2 from the air with chemical filters or by boosting reactions occurring as rocks weather. Colin Axon of Brunel University in Uxbridge, UK, and Alex Lubansky at the University of Oxford estimated what it would take to remove the 30 gigatonnes of CO2 we emit every year.

That would mean processing 75,000 Gt of dry air. Scaling up proposals to filter air would use 180 Gt of clean water per year,

depriving 53 million people of water, on top of the 66 per cent of the world’s population who will face water shortages by 2025.

Enhancing rock weathering is

Cost of carbon fixes no better. It would call for 100 Gt of olivine, a common mineral. This is 12,500 times more than is produced worldwide. To deal with 30 Gt of CO2 we would need to

spread the olivine 1 centimetre thick over 3.6 billion square kilometres of dry land, 1000 times more than Earth has available.

Axon says his calculations are rough. “Still, I’m confident that a CO2 removal scheme would have to be in the order of 1000 times larger than any existing industry.” He presented the estimates at the Planet Under Pressure conference in London last week.

Malaria drug reviewWHY US soldier Robert Bales killed 16 Afghan civilians last month remains a mystery, but his actions have revived a dispute over the use by US forces of an antimalarial drug that can cause psychiatric side effects.

On 20 March – three days after the massacre – the army expedited a review of whether mefloquine was being prescribed properly.

Mefloquine, sold under the trade name Lariam, was developed by the army to prevent malaria resistant to the previous

treatment, chloroquine. In tests the drug caused psychiatric symptoms in nearly a third of cases, sometimes including depression and psychosis.

In a 2009 memo, the US army ordered alternative drugs be used where possible. It also requested that soldiers on the drug suffering anxiety, depression or confusion should stop taking it.

Furthermore, the memo banned mefloquine for soldiers who, like Bales, had recently suffered traumatic brain injury. It is not known whether Bales was taking mefloquine or not.

Bad attitude FROM the assertion of Rick Santorum (pictured) that global warming is a hoax to Rick Perry’s support for intelligent design, the current Republican presidential primaries can seem like a science-free zone.

Far from being a recent phenomenon, such comments reflect distrust in science among US conservatives that has been building in recent decades. So says Gordon Gauchat at the University

–No nuclear for Oldbury–

–Science, schmience–

Fukushima effect rolls onTHE after-effects of Japan’s megaquake and tsunami continue to be felt. Two planned UK power stations have become the latest victims of the anti-nuclear sentiment that followed the crisis at the Fukushima Daiichi power plant last year.

German utility companies RWE and E.ON have pulled the plug on a joint project to build nuclear reactors at Wylfa on the island of Anglesey and Oldbury in Gloucestershire. The firms blame a shortage of cash following the German government’s decision last year to abandon nuclear power.

“There is no doubt that the withdrawal is a symptom of a much wider post-Fukushima effect,” says Gordon MacKerron of the University of Sussex in Brighton, UK.

Italy and Switzerland have also

dropped plans for future plants. And then there’s China’s delay in the construction of new plants pending a safety review. “The longish pause in Chinese ordering is perhaps the most spectacular knock-on effect from Fukushima,” says MacKerron.

The UK’s nuclear ambitions were not stymied by Fukushima. Wylfa and Oldbury were among eight sites chosen for a new generation of reactors. France’s EDF and the Franco-Spanish NuGen remain committed to building UK reactors.

Germany’s decision may not mean a boost for greener energy. “Investment is stalling generally across the energy industry, including the major investment needed for offshore wind projects,” says Sue Ion of the Royal Academy of Engineering in London.

“A CO2 removal scheme would have to be in the order of 1000 times larger than any existing industry”

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