Optimal gases for stratospheric aerosol injection is sulphur dioxide
Q. A climate engineering technique ‘stratospheric aerosol injection’ involves injection of which gas?- Published on 10 Mar 16a. NO2
b. SO2
c. Inert gases
d. O2
ANSWER: SO2
- Stratospheric aerosol injection (SAI), the boldest and also the most risky of climate engineering interventions, involves spraying into the stratosphere fine, light-colored particles designed to reflect back part of the solar radiation before it reaches and warms the earth.
- SAI proponents claim that this could bring down the global temperature by as much as 1°C — a substantial amount in the climate change context.
- The optimal gases for injection, such as sulphur dioxide SO2 can be produced in abundance.
- There are also precedents from nature. The 1991 volcanic eruption of Mount Pinatubo in the Philippines injected 20 megatonnes of SO2 into the stratosphere, cooling the globe significantly for a couple of years.
- But SAI also has the potential for disastrous side effects, crossing national boundaries. The Pinatubo volcanic eruption is also said to have reduced precipitation, soil moisture, and river flow in many regions. Injection of sulphur compounds into the stratosphere is likely to increase acid deposition on the ground and also contribute to ozone layer depletion.
