When a raindrop lands on a porous surface, air from the pores forms small bubbles, which float to the surface and release aerosols. Such aerosols carry the scent, as well as bacteria and viruses from the soil. Raindrops that move slower tend to produce more aerosols; this explains why petrichor is more common after light rains. Members of the Actinomycetes, gram-positive bacteria, are responsible for producing these aerosols.
The human nose is sensitive to geosmin and can detect it at concentrations as low as 0.4 parts per billion. Some scientists believe that humans appreciate the rain scent because ancestors may have relied on rainy weather for survival. Camels in the desert also rely on petrichor to locate sources of water such as oases.
It’s called “petrichor,” if you want to do a deeper dive on it. But the ELI5 answer is that what you’re smelling is basically the smell of wet dirt, or more specifically a chemical released by bacteria in the dirt.
Moist air also tends to enhance scents, as well, so you’re able to smell things that you might not otherwise not notice on a dry day.
Plants produce a bunch of juices. When it rains all those juices are washed off of the plants by the rain and when that water evaporates with the plant juices in it you get that smell.
It’s called petrichor, which is a greek compound word from petra, rock, and ichor, an ancient greek word that was what people believed Gods had instead of blood. So basically blood of the stone.
Everyone is saying petrichlor but there is another smell associated with spring and summer thunderstorms, and that is the smell of ozone, which is formed from lightning.
Where I’m from, when it rains in the spring, the farmers put cow shit over their fields. They can only do it during rain forecasts to help with the smell, but still.
I can only associate the smell of spring rain with cow shit.
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So I need to provide a longer explanation- it’s called Petrichor
“The smell is primarily caused by the release of volatile compounds, including geosmin, from soil bacteria and plant oils when rain hits dry ground”
Petrichor
When a raindrop lands on a porous surface, air from the pores forms small bubbles, which float to the surface and release aerosols. Such aerosols carry the scent, as well as bacteria and viruses from the soil. Raindrops that move slower tend to produce more aerosols; this explains why petrichor is more common after light rains. Members of the Actinomycetes, gram-positive bacteria, are responsible for producing these aerosols.
The human nose is sensitive to geosmin and can detect it at concentrations as low as 0.4 parts per billion. Some scientists believe that humans appreciate the rain scent because ancestors may have relied on rainy weather for survival. Camels in the desert also rely on petrichor to locate sources of water such as oases.
Basically bacteria eat things and poop into the dirt and water reactivates the poop so it smells more.
Humans can detect the smell of “geosmin” better than sharks can smell blood in the ocean.
It’s probably petrichor you’re talking about. It’s the smell of minerals and chemicals in soil after it gets flushed out from the rain.
It’s called “petrichor,” if you want to do a deeper dive on it. But the ELI5 answer is that what you’re smelling is basically the smell of wet dirt, or more specifically a chemical released by bacteria in the dirt.
Moist air also tends to enhance scents, as well, so you’re able to smell things that you might not otherwise not notice on a dry day.
Plants produce a bunch of juices. When it rains all those juices are washed off of the plants by the rain and when that water evaporates with the plant juices in it you get that smell.
It’s called petrichor, which is a greek compound word from petra, rock, and ichor, an ancient greek word that was what people believed Gods had instead of blood. So basically blood of the stone.
Everyone is saying petrichlor but there is another smell associated with spring and summer thunderstorms, and that is the smell of ozone, which is formed from lightning.
I remember when I was living in Vegas I could smell lake mead and lake Las Vegas from like 10 miles away when I was in the car.
Petrichor!
One of my favorite words. Organic matter getting stirred up by rain, especially after a period of relative dryness. it’s so distinctive and so nice.
And if you want the perfume version of that smell, try Black March by Chris Brosius: https://www.cbihateperfume.com/402
Wow. The responses here hit hard.
OP: what’s that smell after a rain that’s kind of nostalgic?
Responses: poop. Bacterial poop.
I always thought it was just the smell of the wet street.
This group is awesome! Thanks guys!
Where I’m from, when it rains in the spring, the farmers put cow shit over their fields. They can only do it during rain forecasts to help with the smell, but still.
I can only associate the smell of spring rain with cow shit.
Ah, the daily petrichor post. Can it be added to a reddit frontpage faq or something?
anyone else know what petrichor is because of that doctor who episode?