Correct Option
The correct option is 2 only
Explanation
Normally, temperature decreases with an increase in elevation in the troposphere, a phenomenon known as the normal lapse rate. Temperature inversion, or thermal inversion, is a reversal of this normal behavior, where a layer of warm air lies over a layer of cold air near the ground.
Statement-wise Analysis
- Statement 1 is Incorrect: Temperature inversion is defined as the condition in which temperature increases with altitude rather than decreasing. In this scenario, the warm air layer acts as a lid, trapping the cooler air and pollutants near the surface.
- Statement 2 is Correct: Temperature inversion is typically a short-duration phenomenon, often occurring during long winter nights with clear skies and still air. It is not permanent in nature in the tropics; usually, the heat of the day breaks the inversion as the earth's surface warms up.
- Statement 3 is Incorrect: Over polar areas, temperature inversion is a normal and common phenomenon throughout the year. The surface remains snow-covered (high albedo) and loses heat rapidly through radiation, keeping the surface air much colder than the air aloft.
Key Takeaway
Temperature Inversion requires long nights, clear skies, and stable air to allow significant radiative cooling of the earth's surface, causing the air immediately above the ground to become colder than the air at higher altitudes.