Cirrus cloud thinning and sulphate injection — UPSC Prelims PYQ 2019

In the context of which of the following do some scientists suggest the use of the cirrus cloud thinning technique and the injection of sulphate aerosol into the stratosphere?

1. Creating the artificial rains in some regions
2. Reducing the frequency and intensity of tropical cyclones
3. Reducing the adverse effects of solar wind on the Earth
4. Reducing the global warming

Explanation

Option (d) is correct

• The cirrus cloud thinning technique and the injection of sulfate aerosol into the stratosphere are proposed methods aimed at reducing global warming. Cirrus clouds are thin, wispy clouds that form at high altitudes and do not reflect much solar radiation back into space, thereby creating a greenhouse effect.
• The higher the altitude at which they form, the larger the warming effect on the climate. And in a warmer climate, cirrus clouds form at higher altitudes. These clouds could be thinned out—reducing their warming effect—by seeding them with aerosol particles such as sulfuric or nitric acid, which act as “ice nucleating particles” (INPs).

Answer: (d) Reducing the global warming; Difficulty Level: Easy