SOUTH MISSISSIPPI (WLOX) - If you’re like me, one of my favorite parts of a summertime storm is the smell of rain. It’s an earthy, clean odor that many of us enjoy. However, it’s not the water we’re smelling, but a chemical concoction involving plants and bacteria.
According to The Smithsonian, two Australian scientists coined the term petrichor to describe the distinct smell of rain. During a dry spell or a drought, many plants produce oils that signal the plant to stop growing. After a steady rain, these oils are released into the air. Plant oils can also mix with other chemicals produced by bacteria within the soil. These bacteria produce a chemical called geosmin during dry spells. As the rain reaches the surface, this chemical is released into the air. It gives the air an earthy aroma after a shower or storm.
Not only can plants and bacteria play a role, but ozone is another factor. If you’ve ever been able to smell rain in the distance, chances are you’re smelling ozone. This is a chemical produced from lightning. The electrical charge from lighting is so strong that is can split oxygen molecules in the atmosphere, and rearrange them to make the compound ozone (this is three oxygen atoms bonded together). Ozone has a smell that resembles chlorine, and strong winds can carry these molecules away from thunderstorms.
The next time you get a whiff of a summertime storm, you’ll now know what you’re really smelling!
For an further look at the smell of rain, and to find out why humans are so sensitive to the smell, you can check out more right here.