After thermal inversion, pollutants pile up in

Options

A. Hanging cool air
B. Hanging warm air
C. At the boundary of cool and warm airs
D. Soil

Answer

**Step-by-Step Solution:**

1. **Understanding Thermal Inversion:**
- Thermal inversion occurs when a layer of warm air traps a layer of cooler air beneath it. This phenomenon prevents the normal rising of air and can lead to the accumulation of pollutants.

2. **Mechanism of Pollutant Accumulation:**
- In normal atmospheric conditions, warm air rises, allowing cooler air (and any pollutants it contains) to disperse. However, during thermal inversion, the warm air acts as a lid, preventing the cooler air (and the pollutants within it) from rising.

3. **Identifying Where Pollutants Accumulate:**
- Since the warm air traps the cooler air below, the pollutants that are normally dispersed in the atmosphere become concentrated in the cooler air layer. This leads to a buildup of pollutants in that layer.

4. **Evaluating the Options:**
- Given the options, we need to determine where the pollutants are likely to accumulate after thermal inversion.
- Option 1: Hanging cool air - This is the correct answer, as pollutants pile up in the cooler air that is trapped beneath the warm air.
- Option 2: Hanging warm air - This is incorrect, as warm air does not hold pollutants.
- Option 3: Warm air rises over the cool air - This is also incorrect, as the warm air prevents the cool air from rising.

5. **Conclusion:**
- After analyzing the situation, we conclude that after thermal inversion, pollutants pile up in the hanging cool air.

**Final Answer: Pollutants pile up in hanging cool air.**

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