Given below are two statements:
Statement (I): Atmospheric stability is important because it determines the ability of pollutants to disperse vertically in the atmosphere.
Statement (II): In summer season in India, the atmosphere is generally stable.
In the light of the above statements, choose the correct answer from the options given below:

Correct option is C

Statement (I) is correct because atmospheric stability directly influences how pollutants are dispersed in the atmosphere. In stable atmospheric conditions, vertical motion is restricted, limiting the upward dispersal of pollutants, which may lead to higher concentrations of pollutants near the ground. In contrast, in an unstable atmosphere, air can rise more freely, allowing pollutants to disperse vertically and mix into the upper atmosphere, thereby reducing their concentration at lower levels.
Statement (II) is incorrect because, during the summer season in India, the atmosphere is often unstable, especially during midday when solar heating is strongest. The intense heating at the Earth's surface causes air to rise, promoting vertical mixing and creating unstable conditions in the lower atmosphere. This is a characteristic of the tropical and subtropical climates experienced in India during the summer, where convection currents are frequent, enhancing vertical dispersion.
Information Booster Atmospheric stability is a measure of the atmosphere's tendency to either resist or enhance vertical movement. In a stable atmosphere, cooler and denser air layers remain near the Earth's surface, with warmer, lighter air above, suppressing vertical movement. This condition leads to limited dispersion of pollutants and can create temperature inversions, where pollution gets trapped near the ground, causing poor air quality.
Unstable atmospheric conditions, however, facilitate vertical mixing and help disperse pollutants away from the source. In such cases, the warm air at the Earth's surface rises, causing convection and reducing pollutant concentration near the ground. Factors that influence stability include surface temperature, altitude, and the presence of temperature inversions.
· Temperature Inversions: Inversions, where the temperature increases with altitude, often occur during winter and nighttime. Inversions trap pollutants near the ground, leading to increased pollution levels in urban areas.
· Summer Instability in Tropical Regions: In tropical regions, like India, summer is marked by intense solar radiation that heats the land surface. This heating causes warm air to rise, fostering atmospheric instability and enhancing the vertical dispersion of pollutants.
· Seasonal Variation: Stability conditions vary seasonally. Winter months often bring stable conditions conducive to pollution accumulation, whereas summer months promote more mixing due to warmer temperatures and convective activity.