Breaking it Down with Brittney - Smog

Let’s start with the basics: high and low pressure. High pressure overhead will produce air that tries to sink down to the surface and low pressure overhead will produce air that rises up from the surface. Air generally cools as it rises; if air warms as it rises, that’s called an inversion because the air is inverted put in the opposite order. Cooler air is more dense than warmer air and cannot rise above a layer of warm air under most circumstances. Smog occurs when warmer, sinking air caused by a ridge of high pressure traps cooler air below it, creating a sliver of air that becomes stagnant and unable to clear out and all the filth in the air starts to accumulate in that layer.