Could a man-ma de ‘volcano’ save the planet?

Don’t scoff. It’s a plan, backed by Bill Gates, that’s just one of the wacky ideas scientists are exploring to stop global warming

CLIMATE-CHANGE activists are once again warning of ecoArmageddon if we don’t mend our global-warming ways.

In a dramatic, opening speech at the UN climate talks in Poland last week, David Attenborough struck a doomsday note when he told delegates: ‘If we don’t take action, the collapse of our civilisations and the extinction of much of the natural world is on the horizon.’

But the truth is we’ve proved pretty resistant to such messages before. We may make a few minor adjustments to our lives, but on the whole we carry on burning planet-warming fossil fuels and releasing greenhouse gases regardless of the dire consequences.

Which is why scientists are formulating a host of ‘geoengineering’ emergency Plan Bs to try to safeguard our planet by manipulating the climate.

They include creating fake volcanic explosions to cloud our skies, moving the Earth further from the Sun — and even shrinking humankind so that we create far fewer greenhouse gases.

The projects sound like the stuff of comic-book fiction, but the science is serious. So could one of these schemes ever seriously come to our rescue?

FAKE VOLCANIC EXPLOSIONS

AN ENGINEERING team partfunded by Bill Gates of Microsoft has announced it is seeking ways to dim the sun by mimicking the effects of a huge volcanic eruption.

The Harvard University scientists hope to prove that by spraying tiny particles into the stratosphere, they could reduce global warming by reflecting some of the Sun’s rays back into space before they hit the Earth.

The experiment aims to replicate what happened naturally in 1991 when Mount Pinatubo erupted in the Philippines and threw 20 million tonnes of sulphur dioxide into the stratosphere.

The solar ray-blocking chemical clouds cooled the planet by about 0.5c for 18 months. If such a reduction were sustained, it could prevent some of the worst effects of climate change, saving Arctic ice and coral reefs, and protecting lowlying communities from floods.

The $3 million ‘stratospheric controlled perturbation experiment’ (Scopex) outlined by the Harvard team and scheduled for early next year, involves sending an airship 12 miles above the south-west United States to release small plumes of up to 1kg of chalk dust (calcium carbonate) to observe how it scatters sunlight and changes the chemistry of the stratosphere. They hope it could prove a ‘remarkably inexpensive’ way of cooling the planet, costing some €2.2 billion a year.

According to David Keith, a member of the team, ‘it would be crazy not to research it’ after the success indicated by computer models.

However, scientists warn that the strategy would disrupt global rainfall, causing drought and famine in large parts of the world. Piers Forster, a professor of climate physics at Leeds University, fears that up to 4.1billion people could be harmed by changes in rain patterns. ‘The most striking example of a downside would be the complete drying-out of central Africa,’ he says.

MAKE THE EARTH MOVE

BELIEVE it or not, shifting Earth to a cooler spot away from the Sun has been seriously considered by Nasa scientists. Even more outlandish is their suggestion that this could be achieved by diverting comets into the direction of our home planet.

Greg Laughlin, a professor of astronomy at Yale University, says scientists could carefully direct a comet or asteroid so that it sweeps just past us — and its gravitational pull would spin Earth further out into the solar system.

‘The technology is not at all farfetched,’ he maintains. ‘It involves the same techniques that people now suggest could be used to deflect asteroids or comets heading towards Earth.

‘We don’t need raw power to move Earth, we just require delicacy of planning and manoeuvring.’

Fellow believers say the plan could add another six billion years to the lifetime of our planet — effectively doubling its working life.

However, critics have attacked the plan in the journal Astrophysics and Space Science, arguing that even a tiny miscalculation would cause a collision so catastrophic that it would destroy all life bar a few microbes.

What’s more, if Earth were pushed from its current position the Moon may be knocked out of orbit, too, drifting off into space, further upsetting our climate by its effect on the ocean currents which regulate the climate (transporting cold water from the poles to the tropics and vice versa) and tides.

BREED TINY HUMANS

AN OXFORD University philosopher has made an even more radical proposal that we should genetically engineer our children to be much smaller, so that they eat less, make fewer demands on the environment and overall emit fewer greenhouse gases.

In 2012, Dr Rebecca Roache also suggested we could genetically modify these mini-humans to be ‘greener’ by making them allergic to meat and perhaps dairy, so that we no longer need to breed and farm cattle (a cow produces around 100kg of methane gas per year — which is 20 times more potent a greenhouse gas than carbon dioxide).

Further, genetic modification could produce babies with lightreflecting eyes like a cat’s. ‘If everyone had cat eyes, you wouldn’t need so much lighting,’ wrote Dr Roache and colleagues in the journal Ethics, Policy and Environment.

They add: ‘Human engineering deserves further consideration in the debate about climate change.’ So bring on the tiny cat-eyed vegan children!