The after-rain smell is called petrichor

The after-rain smell is called petrichor Today’s Video of the Day comes from the American Chemical Society’s Reactions series and explains how the distinct smell that fills the air after a fresh rain is called petrichor.

Petrichor is derived from the Greek language and means “blood of stones,” originally coined in the 1960s by Australian scientists Richard Thomas and Isabel Bear. The after-rain smell is called petrichor as seen above in video will explain the smells behind the after rain.

The two main sources of the scent are plants and bacteria living in soil. Petrichor refers to the yellow oil that can be extracted from rocks, clay, and soil and contains fatty acids from plants. Some plants secrete oils during dry periods, and when it rains, these oils are released into the air. The second reaction that creates petrichor occurs when chemicals produced by soil-dwelling bacteria known as actinomycetes are released. These aromatic compounds combine to create the pleasant petrichor scent when rain hits the ground.

A recent study from researchers at MIT suggests an aerosol effect is the main cause of the smell of dust after a light rain. Petrichor was coined by two scientists, Isabel Joy Bear and R. G. Thomas of Australia’s Commonwealth Scientific and Industrial Research Organization, in 1964. The “rain smell” is caused by a chemical in the bacteria called geosin, which is released by the bacteria as they die.Geosin is a type of alcohol molecule and has a very strong scent. The bacteria are extremely common

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By Rory Arnold, Earth.com Staff Writer

Video Credit: American Chemical Society