This and the "Santa Ana fog" above constitute examples of an air inversion.

Driving to the dock, Brody had heard on the radio that the pollution in New York City had reached a crisis stage - something about an air inversion.

There were disjointed images, like the Kilbuck Mountains in the distance flattened by an air inversion in the utter cold.

You are likely to experience the effect of the pollution, as it is generally at its worst in December into March, when air inversions often keep bad air trapped over the city.

In upper air inversion, the bending will be limited to the layer involved but the bending will extend the path of the beam, possibly beyond the usual transmission horizon.

The claim that the emissions were within Federal standards assumed a steady wind across the site; air inversions occur two out of three days in East Liverpool.

The pollution, trapped by the air inversion between high ground, makes her eyes tear, her skin itch.

The fall months brings dense river fog, especially during the overnight and morning hours, as a cold air inversion lingers above the relatively warm river surface.

In 1948, an air inversion over Donora trapped pollution from nearby metal processing plants, killing 20 and causing health complications for many more.

And it is in a flood plain over two underground sources of fresh water, and in a valley where air inversions can trap pollutants.