Geoengineering worries Aussies

Fiona MacDonald, ScienceAlert 4 Sep 09;

In response to the claim that geoengineering will need to be used if humans can't reduce their emissions, Australian scientists have voiced concern that the consequences may be too dangerous.

A report by the UKs Royal Society released on the first of September evaluated whether using radical geoengineering techniques was a feasible solution to climate change. The conclusion was that, although these techniques are unproven and potentially dangerous, they may be our only hope.

"It is essential that we strive to cut emissions now, but we must also face the very real possibility that we will fail," said Professor John Shepherd, chair of the study, in a Royal Society media release.

"Geoengineering and its consequences are the price we may have to pay for failure to act on climate change," he added.

However, Australian scientists have warned that we should not give up on trying to reduce human emissions as yet, as even as a last resort geoengineering may be too dangerous.

"Geoengineering responses are like the old lady who swallowed a spider to catch the fly, creating a whole set of new problems," said Professor Ian Lowe, President of the Australian Conservation Foundation.

The main types of geoengineering techniques are Carbon Dioxide Removal (CDR) and Solar Radiation Management (SRM).

CDR solutions include CO2 capture, enhanced weathering and afforestation. The Royal Society's report considered these to be the best option for preventing climate change now, as they have fewer uncertainties and risks.

SRM techniques include stopping the Sun's rays reaching Earth, with mirrors or by injecting dust into the upper atmosphere. These were considered more risky by the Royal Society's report and were advised to be used only if temperatures had reached a dangerous level.

Professor John Buckeridge, a professor of Natural Resources Engineering at RMIT University, said we needed to focus on reducing the rampant consumption of natural resources rather than geoengineering.

"Many things that have been done for good reasons, have turned out to be disadvantageous, e.g. introduction of exotic species for “recreation”. Geoengineering has the potential to reap even greater havoc," he said.

However, one scientist believes that the report has accurately assessed the urgency of climate change and the need for action.

Kevin Walsh, an Associate Professor of meteorology from the University of Melbourne, said, "The report correctly concludes that there is no substitute for a concerted campaign to reduce greenhouse gas emissions, while acknowledging that some geoengineering options may be helpful in the future," he said.

In the Royal Society's media release, Professor Shepherd acknowledged that geoengineering methods could have catastrophic consequences similar to those of climate change itself, but added that it was important to develop 'Plan B' now.