Geoengineering debate causes storm as climate change arguments heat up

11 Feb 2015

Mirroring the effects of volcanic eruptions, manually, is controversial

Two reports into how best to reduce carbon dioxide levels on Earth have claimed that a proposed intervention technique – geoengineering – is not the solution to global warming.

Climate intervention approaches are a hot topic as the planet gradually heats up, destroying the ice caps and making global harvests more and more unpredictable as weather patterns shift further and further from the norm.

Elsewhere, recent research into using biofuels to reduce carbon dioxide emissions fairly ripped that idea to shreds.

The National Research Council in the US has looked at reducing emissions into the atmosphere, as well as manufacturing ways to reduce heat retained from our current levels of sunlight, as a way of halting global warming.

What they discovered is that there’s “no substitute” for “dramatic reductions” in emissions of greenhouse gases.

Two reports, one answer

In the first of the two reports, the National Academy of Sciences looked at carbon dioxide removal and reliable sequestration. It suggests possible approaches to removing carbon dioxide, such as low-till agriculture, reforestation and afforestation, ocean iron fertilisation, and land and ocean-based accelerated weathering.

Nothing controversial there.

The second report, however, titled Reflecting Sunlight to Cool Earth, is about alternative approaches. For example, replicating the effects of volcanic eruptions, which greatly affect the Earth’s temperature.

Global temperatures were reduced by 0.5°C between 1991-1994 when emissions of just 20m tonnes of sulphur erupted out of Mount Pinatubo in the Philippines.

A similar human exercise to curb the warming from a doubling of carbon dioxide concentrations in the air would be “at least an order of magnitude less than the cost of decarbonising the world’s economy”, the report says.

Geoengineering, an answer nobody wants

Changing the fraction of incoming solar radiation that reaches the surface of the Earth is a back to front look at the problem, with many thinking of it as illogical, when reductions are obviously more pertinent – especially considering the warming of the planet is only one issue of our current emission-mad lifestyles.

Other things such as the acidification of oceans would remain unarrested should such projects be undertaken. The results of geoengineering would also never, truly, be fully established without potentially disastrous testing. Public support is not really behind geoengineering, with all tests to date only undergone on computers.

“One attempt in Britain in 2011 to conduct an outdoor test of some of the engineering concepts provoked a public outcry,” reported The New York Times. “The experiment was eventually cancelled.”

The report, according to New Scientist, shifts away from previous works on geoengineering, such as the UK Royal Society’s 2009 study.

“The idea advanced by the Royal Society that albedo modification is some kind of Plan B has largely fallen out of favour,” said Simon Nicholson at the American University in Washington, DC.

Crash and burns

“That scientists are even considering technological interventions should be a wake-up call that we need to do more now to reduce emissions, which is the most effective, least risky way to combat climate change,” said committee chair Marcia McNutt, editor-in-chief of Science and former director of the US Geological Survey. 

“But the longer we wait, the more likely it will become that we will need to deploy some forms of carbon dioxide removal to avoid the worst impacts of climate change.”

One problem with planning for geoengineering is, in future, you won’t know who will engage in their own approaches for their own gains.

Volcanic eruption image via Shutterstock

Gordon Hunt was a journalist with Silicon Republic