Cars and trucks were barreling north along Route I-10 toward Phoenix, which had disappeared under brown smog.

The central characters live in an isolated apartment building covered in a murky brown smog.

They were heading toward the range of mountains that rose high above a layer of light brown smog from the city.

But every time you breathe in, that brown smog enters your lungs.

Farewell, belt of thick brown smog cinching Manhattan's waist.

A heavy brown smog now falls over our every effort to slog through the miasma of daily life.

On a clear winter day, a belt of brown smog tracks the boundary between Texas and Chihuahua.

A city of brilliant sunshine and vivid colors, it is also often blanketed by hazy brown smog.

Much of the area is frequently covered with a brown smog.

As he lay waiting, the afternoon light waned, and a thickening sludge of dirty brown smog nuzzled the window.