Solar Geoengineering 'Only Option' To Cool Planet Within Years, UN Says

The United Nations Environment Program (UNEP) is investigating the potentials and dangers of solar geoengineering technologies, stating that these controversial interventions are humanity's 'only option' to quickly cool the planet within years. An anonymous shares an excerpt from a Motherboard article: In a report published by UNEP in February, an independent panel describes what's currently known about so-called solar radiation modification, also called solar geoengineering, and concludes that, despite its great potential, it's not viable or even safe right now. Nonetheless, amid growing calls from governments to find an emergency brake for climate change -- and ongoing, independent efforts to develop solar geoengineering technology -- the UNEP is calling for a full-scale global review of the tech and eventual multinational framework for how it should be governed. The recommendations have some opponents fearing that this amounts to endorsement of adopting the technology -- a move that could create an even worse environmental crisis by messing with intertwined natural climate systems or pulling the focus away from mitigation measures, as well as further widening the inequalities that already exist as a result of climate change.

Solar radiation modification describes a range of technologies that aim to cool our overheated planet by reflecting incoming sunlight back out into space, or making it easier for heat coming off the earth to escape. Blocking out just two percent of sunlight could, according to some estimates, totally offset the warming that comes from doubling the amount of CO2 in the atmosphere from pre-industrial levels. It's a tantalizing prospect, but comes with a raft of issues. For one, as the report notes, the best large-scale evidence we have that it could even work is from volcanic eruptions, where the smog cooled the globe for a couple of years afterwards. Most of the actual research has involved climate modeling, theoretical analyses or cost estimates. Some groups have conducted small-scale indoor experiments of how the tech might work. No one's taken the trials outdoors yet.

Even if we knew more, it's not a be-all-end-all climate solution, said UNEP's chief scientist, Andrea Hinwood. 'SRM technologies, should they be considered at some point in the future, do not solve the climate crisis because they do not reduce greenhouse gas emissions nor reverse the impacts of climate change. The world must be crystal clear on this point,' she said in a UN media release. What solar geoengineering might do though, is buy the planet some time. The UNEP report highlights that even if we fully halted CO2 emissions right now, it could take at least until the end of the century to see a drop in temperature. 'Make no mistake: there are no quick fixes to the climate crisis,' wrote UNEP executive director Inger Andersen in the report. 'Increased and urgent action to slash greenhouse gas emissions and invest in adapting to the impacts of climate change is immutable. Yet current efforts remain insufficient.' Despite firm opposition from some, the message from the UNEP report seems to be to proceed with caution. 'While UNEP is concerned, it is naive to think research will cease and the issues will disappear. We cannot afford to bury our heads in the sand,' said chief scientist Hinwood.

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