I am quite curious where they got nitrous oxide from in the first place. It's generally seen as a potential pitfall of OIF I thought, at least how it relates to potential geoengineering schemes.
On Monday, October 8, 2018 at 5:57:29 PM UTC-4, Matthias Honegger wrote: > > > Link to the article online > <https://www.theguardian.com/environment/2018/oct/08/geoengineering-global-warming-ipcc> > > Geoengineering may be used to combat global warming, experts say > > IPCC authors suggest there is high agreement that injection of chemicals > into stratosphere could help limit rises > > > Jonathan Watts, the guardian, 8. Oct. 18 > > > The world may increasingly look to geoengineering in the wake of the > latest UN climate report, which says it could be adopted as a temporary > “remedial measure” if the world heads towards dangerous levels of warming. > The authors of the new 1.5C study by the Intergovernmental Panel on > Climate Change say there is high agreement that the injection of millions > of tonnes of sulphur dioxide or nitrous oxide into the stratosphere could > help limit temperature rises to the most ambitious target of the Paris > accord. > But the authors warn there are major uncertainties about the social, > environmental and ecological impacts, which mean the world would be far > better off if policymakers strengthened natural cooling systems such as > forest cover and accelerated efforts to reduce carbon emissions. > The lengthy document – which was approved at the weekend by all 195 > nations in the UN – mentions several options for man-made interference in > climate systems, including ocean fertilisation, carbon dioxide removal, > marine cloud brightening, cirrus cloud thinning and ground-based albedo > modification. > But it focused most on stratospheric aerosol injection, a technique that > essentially mimics the effect of a volcano by pumping gas into the sky that > turns into aerosols, which reflect part of the sun’s heat. > Although the authors do not include such strategies in their pathways to > 1.5C above pre-industrial temperatures, they raise the possibility that it > could be used as a supplementary measure if this target is missed. > “If mitigation efforts do not keep global mean temperature below 1.5C, > solar radiation modification can potentially reduce the climate impacts of > a temporary temperature overshoot, in particular extreme temperatures, rate > of sea level rise and intensity of tropical cyclones, alongside intense > mitigation and adaptation efforts,” the report observes. > A search for palliatives will be necessary as the world is almost certain > to miss the 1.5C goal. Current national pledges are forecast to lead to at > least 3C of warming by the end of the century – and that is if governments > keep their commitments. > The IPCC is clearly hesitant to endorse such emergency measures in part > because this could allow government leaders to continue pushing problems > into the future, but also because of the immense risks involved. > The report notes that the injection of sulphur dioxide would change > rainfall patterns and weather circulation as well as disrupting > stratospheric chemistry and ice formation. It could also result in more > ultraviolet light exposure, which would have a negative impact on human > health. > Ethical and institutional questions also arise over who would oversee such > operations and which areas would be affected. The report suggests a number > of UN organisations as possible supervisory bodies. But authors also > observe that there are scarcely any laws or regulations to stop any country > that wants to push ahead by itself. The only guideline cited was the > Convention on Biodiversity which states “no climate-related geoengineering > activity that affects biodiversity may take place.” > There are doubts also over effectiveness. While the aerosols might > constrain temperature rises, they would not stop the accumulation of carbon > dioxide in the atmosphere and the acidification of the oceans. What happens > when this “temporary measure” is halted is also an area of concern, as the > planetary system might suddenly be hit by a surge in temperature. > The IPCC says these uncertainties constrain the ability to implement solar > radiation management in the near future. But with the 1.5C target current > on course to be overshot at some point between 2030 and 2052, the urgency > is likely to grow. > Johan Rockström, coauthor of the recent Hothouse Earth study, said the > IPCC report was likely to stimulate discussion of these extreme emergency > measures. > “I think this will raise solar radiation management to the highest > political level. We currently have no framework for this,” he said. “I’m > very scared of this technology but we need to turn every stone now.” > James Hansen said the tipping point in public opinion was more likely to > come at a slightly higher temperature, but by then it may already be too > late. > “2C would force geoengineering on today’s young people. Geoengineering, if > global temperature passes 2C, would start, at the latest, once ice sheet > collapse begins,” he told the Guardian. “Unfortunately, because of the > inertia of the system, geoengineering then would probably be too late to > prevent locking in the eventual loss of coastal cities.” > > Link to the article online > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To post to this group, send email to geoengineering@googlegroups.com. Visit this group at https://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout.
