Stratospheric Sulfate Aerosols (geoengineering) - Arguments For The Technique

Arguments For The Technique

The arguments in favour of this approach are:

• Natural process: Stratospheric sulfur aerosols are created by existing atmospheric processes (especially volcanoes), the behaviour of which has been studied observationally. This contrasts with other, more speculative geoengineering schemes which do not have natural analogs (e.g. space sunshade).
• Speed of action: Solar radiation management works quickly, in contrast to carbon sequestration projects such as carbon dioxide air capture which would take longer to have an effect, as the latter relies on removing large amounts of carbon dioxide before they become effective; however, gaps in understanding of these processes exist (e.g. the effect on stratospheric climate and on rainfall patterns) and further research is needed.
• Technological feasibility: In contrast to other geoengineering schemes, such as space sunshade, the technology required is pre-existing: chemical manufacturing, artillery shells, fighter aircraft, weather balloons, etc.
• Cost: The low-tech nature of this approach has led commentators to suggest it will cost less than many other interventions. Costs cannot be derived in a wholly objective fashion, as pricing can only be roughly estimated at an early stage. However, an assessment reported in New Scientist suggests it would be cheap relative to cutting emissions. According to Paul Crutzen annual cost of enough stratospheric sulfur injections to counteract effects of doubling CO₂ concentrations would be $25–50 billion a year. This is over 100 times cheaper than producing the same temperature change by reducing CO2 emissions.
• Efficacy: Most geoengineering schemes can only provide a limited intervention in the climate—one cannot reduce the temperature by more than a certain amount with each technique. New research by Lenton and Vaughan suggests that this technique may have a high radiative 'forcing potential'.
• Tipping points: Application of this technique may prevent climate tipping elements, such as the loss of the Arctic summer sea ice, Arctic methane hydrate release, loss of the Greenland ice sheet