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4th June 2023
12:22pm BST
We're all pretty familiar with the smell after some heavy rain, but it turns out that some people are able to smell the rain before it's arrived.
The satisfying, fresh scent in the air after a period of heavy rain, is called 'petrichor' and it's particularly noticeable after a prolonged period of sunshine.
The name petrichor comes from Greek, petros meaning stone - just like in the word 'petrify' - and ichor being the name for the substance that flowed through the veins of the Greek Gods.
So petrichor pretty much means 'blood of the stone', and was coined by mineralogists, Isabel Joy Bear and Richard Thomas, back in 1964.
The smell is produced by a soil bacteria, which releases a chemical called 'geosmin', and humans have a unique ability to smell this chemical.
In fact, we can smell geosmin better than sharks can detect blood.
The reason so many of us like this smell so much is because it is actually intended to be a pleasant scent.
Bacteria in the soil produce the smell to attract organisms into the soil, and in turn spread the bacteria to other places.
When rain hits the ground, it can trap air pockets in the soil. When these bubble up and are eventually released, they take the scent of all the chemicals and micro-organisms in the ground with them.
So this is why we can smell when it's rained. But what about being able to smell when it's about to rain?
Well, according to IFLScience, this is all to do with another chemical: ozone.
This has a distinct smell, sweeter than petrichor, and can sometimes indicate that a storm is on the way.
This is due to pockets of ozone gas being pushed down to ground level by winds in an approaching storm.
This pushes the chemical down to a level that those with a particularly good sense of smell will be able to pick up.
So, if you've always thought you've had a handy knack of being able to predict rain, you might not be imagining this.
Or, you could just check the weather instead of relying on your snout to decide whether to take a coat out or not.
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