Explanation
The correct option is 2 and 3 only.
Ozone (O3) is a crucial atmospheric gas found in small quantities. Its distribution and function vary significantly depending on the atmospheric layer in which it resides. While it acts as a pollutant in the lower atmosphere, its primary and most vital role is in the upper atmosphere, where it forms a protective shield.
Statement-wise Analysis:
- Statement 1: Incorrect. Ozone is not found exclusively in the troposphere. In fact, the highest concentration of ozone is found in the Stratosphere, specifically between 10 and 50 km above the Earth's surface (often referred to as the "Ozone Layer"). While trace amounts of ozone exist in the troposphere (where it is considered a pollutant), the vast majority resides in the stratosphere.
- Statement 2: Correct. The stratospheric ozone layer acts as a critical filter for incoming solar radiation. It specifically absorbs harmful ultra-violet (UV) rays radiating from the sun, preventing them from reaching the Earth's surface in dangerous quantities.
- Statement 3: Correct. Solar radiation, particularly in the UV spectrum, carries high energy. By absorbing these rays, the ozone layer prevents this high-energy radiation from striking the surface. If the ozone layer were absent, these rays would reach the surface, contributing to increased thermal energy (heating) and causing severe biological damage (such as skin cancer and cataracts).
Key Takeaway:
Ozone is primarily located in the Stratosphere (10-50 km), where it absorbs harmful UV radiation. This absorption protects life on Earth and influences the thermal structure of the atmosphere (causing temperature to increase with height in the stratosphere).