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

Scientists propose using stratospheric sulfate aerosols to create a global dimming effect. This is considered a form of solar radiation management or climate engineering. The aim is to limit the impact of climate change caused by rising greenhouse gas levels. Methods to deliver precursor sulfide gases, such as sulfuric acid (H2SO4), hydrogen sulfide (H2S), or sulfur dioxide (SO2), include using artillery, aircraft, and balloons.

Cirrus cloud thinning is another proposed climate engineering technique. Cirrus clouds, being high and cold, trap more heat than they reflect sunlight, leading to a net warming effect. Thinning or removing these clouds would reduce their heat-trapping capacity, resulting in a cooling effect on the Earth's climate.

Therefore, both techniques are suggested to reduce global warming.

Sources:

• Wikipedia - Cirrus cloud thinning
• Wikipedia - Stratospheric aerosol injection