BURLINGTON, Vt. (WCAX) – Step outside today and take a deep breath. That fresh, earthy smell hitting your face? There’s actually some pretty cool science behind it. And the best part? You’re about to get plenty of chances to experience it this week.
That unmistakable “rain smell” has a name: petrichor. It comes from a combination of things happening in your soil and plants when rain arrives after a dry spell.
Here’s what’s going on down there:
Bacteria in the soil called streptomyces release a chemical called geosmin when raindrops disturb them. Think of it like waking up bacteria that have been sleeping in the dry earth – and they’re releasing their signature scent as they stir.
Plants also get in on the action. During dry periods, plants release oils as a survival mechanism. When rain finally arrives, those oils are released into the air, mixing with the geosmin to create that perfect spring smell.
And if you happen to catch a whiff during a thunderstorm? Lightning is creating ozone (O3) by splitting oxygen atoms in the atmosphere. That sharp, clean smell is ozone mixing with everything else.
You’re going to get very familiar with petrichor this week. Rain is in the forecast today and will continue with on-and-off showers throughout the week. We’re definitely starting April off wet, but that just means we should see plenty of May flowers soon!
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