This guest post is by Simon Terry, Executive Director of the Sustainability Council of New Zealand. The risk rating on stratospheric sulphate injection went up another notch on the basis of material presented at a recent geoengineering symposium in Australia organised by the Australian Academy of Science, while the existing climate change risks did not get any better. The event made a useful contribution to the understanding down under of so called ‘geoengineering’ and delivered some perspectives that will be useful internationally, including a review of sulphate injection that raised a new issue: is it completely reversible? More on that below.
While not exactly the “southern hemisphere perspective” that was billed (as the contributors barely exceeded Australia’s borders), it nonetheless delivered strong presentations and discussion — partly as a result of most speakers being specialists in the field related to each technique reviewed but not technique proponents themselves.