The smell, which remains in the air after the rain, called Petrichor (Petrichor)

Two Australian scientists in 1964, the year came up with the term Petrichor, derived from the Greek petra («rock») + ichor («ichor", the liquid that flows in the veins of the gods in Greek mythology) to denote the flavor remains in the air after will be held rain.

In the formation of the smell participates organic compound called geosmin (geosmin). The Greek word means "the smell of the earth." Geosmin is a waste product of soil bacteria of streptomycin and blue-green algae. The most pronounced smell of geosmin can be found, for example, in the earthen basement. Also, the smell associated with "damp", "wet", "musty».

via factroom.ru