Kit Roberts
Many people will be familiar with that wonderful fresh smell that hangs in the air after rain.
It only comes out really strongly when it rains after a prolonged period of sunshine, just like after an April shower.
However it turns out that some people might even be able to smell that all too familiar scent before the rain even arrives.
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Nice trick to avoid getting wet if you can do it.
But are these claims grounded in science, or a superstition?
It's certainly possible to smell the rain afterwards, but a lot of people are sceptical that it can be smelled even before it arrives.
In fact, there actually is a name for the satisfying scent in the air after a period of heavy rain, and it comes from 'petrichor'.
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The name petrichor comes from Greek, petros meaning stone (as in petrify), and ichor, which was the substance that flowed through the veins of the Greek Gods. So petrichor is almost like saying the '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'.
Our ability to smell geosmin is actually extraordinary, even outstripping the ability of sharks to be able detect blood. Look at us being all impressive!
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But why it it so appealing? It turns out there is actually a very good reason for that. The bacteria produces the smell specifically to attract organisms into the soil, and in turn spread the bacteria to other places.
The reason the smell becomes so prevalent after a spell of rain is that when the raindrops hit the ground and flatten out, they can trap pockets of air in there. These then bubble up like tiny aerosols, taking whatever chemicals and micro-organisms happen to be there into the air with them.
But IFLScience documented that there is another source of smell which could impact us. This is the chemical 'ozone'.
Ozone has a distinct smell, which is sweeter than that of petrichor. The scent of ozone can sometimes indicate that a storm is on the way.
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This is because pockets of ozone gas are pushed down to ground level by winds in the approaching storm. That means that they will be at the level where our nostrils are most likely to be able to pick them up.
So it seems that the claim that some people can smell rain coming actually does have some truth behind it.
Extraordinary!