Final answer:
Inversion 1 is explained by pollution being blocked by a large orographic barrier, whereas Inversion 2 is due to pollution being trapped in lower river basins, with temperature inversion playing a key role in trapping pollutants.
Step-by-step explanation:
The best explanations for Inversion 1 and Inversion 2 refer to situations where pollution is impacted by geographical configurations. Inversion 1 typically involves pollution blocked by a large orographic barrier, while Inversion 2 refers to pollution trapped in relatively lower river basins. An orographic barrier can cause air pollutants to become trapped on one side of a mountain range due to the inability of the air to pass over, leading to higher concentrations of pollution. In contrast, lower river basins can trap pollutants because these areas are often surrounded by higher land on all sides, which inhibits air movement and dispersal of pollutants.
A temperature inversion plays a crucial role in these situations by trapping cool air underneath a layer of warm air, preventing the vertical movement of air and thereby, trapping pollutants close to the ground. This inversion can create conditions where convection is suppressed, potentially giving rise to violent thunderstorms if the "cap" is disrupted. It's important to understand these environmental dynamics as they explain why certain areas experience prolonged periods of poor air quality and possibly detrimental health effects.