A new study recommends implementing solar geoengineering, the practice of injecting particles into the stratosphere to partially block the sun’s rays, to combat climate change.
The report, published in the journal Environmental Research Letters, found that solar geoengineering would cost between $2 and $2.5 billion (€1.76 to €2.2 billion) per year – around $500 billion (€439 billion) is invested annually in green technologies around the globe – and could reduce the rate of global warming. The projected costs anticipate a 15-year programme; and take into account the cost of adding new aircraft annually, crew wages and training, maintenance, insurance, fuel and landing charges.
By injecting millions of tonnes of sulphate particles into the stratosphere, solar geoengineering mimics the climate conditions seen after major volcanic eruptions, which have caused global temperatures to drop in the past. The project would lower global temperatures by 0.1°C per year, with a total temperature drop of 1.5°C after 15 years.
As no aircraft currently exists which would be capable of undertaking payload delivery of the nature and scale required by the principles of solar geoengineering, new aeroplanes would have to be built with a wider wingspan and four engines rather than two. The report said: “Developing a new, purpose-built high-altitude tanker with substantial payload capabilities would neither be technologically difficult nor prohibitively expensive.”
Critics argue that while solar geoengineering could be deployed as an emergency “remedial measure” to address drastic temperature rises, it should not be seen as a primary solution to the problems caused by climate change. They are concerned solar geoengineering could be a distraction, diverting attention and funding from the wider issue of addressing the causes of climate change; and that while artificially adjusting the world’s climate may help arrest global warming, it risks causing droughts and crop damage while failing to address other issues stemming from climate change, such as ocean acidification.