

The official term for the smell after it rains - scorxn
http://en.wikipedia.org/wiki/Petrichor

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robotrout
I love this smell. I've been fighting with the wife, who claimed it was from
asphalt, and I knew it wasn't, since I've smelled it in the middle of nowhere.
Turns out, she was actually pretty close, since it's hydrocarbon based.

Somebody should make a perfume based on this. It should be possible to extract
the specific oils responsible.

~~~
gruseom
I love this smell too. Smells are emotionally charged to begin with, and this
is one of the more powerful ones in my experience. The fact that it's so
intermittent and fleeting (small correction to the title: it's the smell after
it's _just begun_ to rain) adds to its mystery. Because of that, I kind of
hope it doesn't get extracted into a product. Perhaps I'm being too nostalgic,
though, sitting in just about the darkest day of winter when it's been -20 for
most of the past month...

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thwarted
I've always been able to smell something distinctive BEFORE it rains. Don't
know what causes that, but I've always thought it was actually change in air
pressure that my nose is misinterpreting as a smell.

~~~
camccann
Are you thinking of a smell with a kind of sharp, metallic or chemical odor,
right before a heavy thunderstorm?

If memory serves me, that's due to the voltage between the storm and the
ground turning O2 molecules into O3 (ozone), which gets spread around by the
storm's winds.

~~~
thwarted
Yeah, I think that describes it pretty well. I don't think I've met anyone
else who claims to be able to smell it.

~~~
ax0n
That is, in fact, ozone. You're not alone. I often smell it ahead of big
storms as well. Of course, I also smelled it after watching the maple tree in
my front yard get zapped 20 feet away with nothing but a window screen and air
between my face and $DEITY knows how many kilovolts.

~~~
camccann
There is some variation in how sensitive people are to individual odors.
Picking up the ozone smell before storms seems to be sufficiently rare that a
lot of people end up wondering if they're the only one.

Anyway, as I said, the ozone is produced by the electrical activity in the
storm--if you're curious, you can get a smell of ozone off of artificial
sources of high-voltage electricity as well. Hanging around a Tesla Coil or
Van de Graff Generator ought to do the trick.

And hey, look at it this way, it's not the storm itself you're noticing--
you're actually _smelling lightning_. How cool is that?

~~~
kellishaver
I've always been able to smell this before a storm as well. I remember when I
was a kid and I would tell my parents, friends, whoever, this fact and they
would just think I was crazy because no one else could smell it.

I have very poor eyesight, so my hearing and sense of smell are extremely
acute.

------
goatforce5
Triple J radio in Australia (the government funded "youth" radio station) has
a science show with a guy called Dr Karl.

<http://en.wikipedia.org/wiki/Karl_Kruszelnicki>

"He holds degrees in mathematics, biomedical engineering, medicine and
surgery. He has also studied astrophysics, computer science and philosophy. He
has worked as a physicist, labourer, roadie for bands, car mechanic, film-
maker, hospital scientific officer, biomedical engineer, TV weatherman, taxi
driver and medical doctor."

He also written a ton of books and won an Ig Noble prize for his extensive
research in to belly button lint colouring.

He is clearly totally awesome.

Anyway, petrichor is old news to listeners of his radio show, as it's been
discussed there numerous times. I highly recommend listening to his podcast,
it's full of all sorts of random sciencey stuff presented in an easy to digest
way:

<http://www.abc.net.au/science/drkarl/scienceontriplej/>

------
chaosprophet
In Tamil, we call this 'manvasanai', which literally translates to the smell
of earth.

~~~
muon
<digression>

As this involves rain and earth, This poem immediately springs in the mind.

The red earth and pouring rain.

Red earth and pouring rain[1] What could my mother be to yours? What kin is my
father to yours anyway? And how Did you and I meet ever? But in love our
hearts have mingled as red earth and pouring rain

[Translated by AK Ramanujan (Kuruntokai - 40)

</digression>

~~~
ryne
Titled: "What He Said"

On a side note, poetry isn't poetry without proper spacing.

------
johnl
I knew we sprayed bananas and tomatoes to ripen during transit to market but
never figured plants used the same technique to delay a process (spraying the
ground with an oil) to retard seed germination until it rains. Pretty neat if
I read the article correctly.

~~~
weaksauce
I don't think that the article infers that but it could be a plausible
explanation for the effect of the oil seeping out but it could also be that
the moisture seeps out first and then when there is none left the oil seeps
out as a last resort.

------
rgrieselhuber
I remember a childhood friend told me that it was the smell of ozone and I
guess it always just stuck. Seems kind of silly now that I think about it.

~~~
bmunro
Not so silly. As elsewhere noted, you will smell ozone when thunder storms are
around. The high voltages involved create 03(ozone) from O2(oxygen).

------
billswift
I sort of doubt plants have much to do with the smell. I used to live in a
basement apartment with lots of exposed brickwork and a shitty heating system.
Every Fall when the temperature started dropping, there would be moisture
condensing on the brick, and it would give off the "rainy earth" smell.

~~~
robotrout
Wrong smell!

Depending upon where on earth you live, I think it's possible that you haven't
smelled this smell. I now live in the Pacific Northwest. I rarely smell it
here, and I miss smelling it. It has to be a hot summer rainstorm, not a
winter drizzle.

The smell you're describing, I think, is just "wet earth smell", which isn't
nearly as pleasant.

------
woadwarrior01
I learnt this (and dozens of other interesting words) years ago from Anu
Garg's AWAD mailing list. <http://wordsmith.org/awad/archives/0404>

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manish
I have never heard any one who has ever said that they do not like this smell.
I wonder what is it in the that makes us so refreshed and happy. My spirits
just sore at this smell.

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muon
The likable smell caused by the bacteria
<http://science.howstuffworks.com/question479.htm>

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10ren
Surely negative ions have got something to do with it?

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EventHorizon
I thought the smell after it rains was ozone, or perhaps something else
oxidizing the inside of my nose.

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paraschopra
I have always had a dream of making a perfume out of this smell. Simply
refreshing!

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mumrah
What about the smell of asphalt after it rains?

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wingo
A nice article for the solstice, thank you :)

------
ikitat
smells like worms

~~~
ax0n
There was a calvin and hobbes in the 80s that stated the very same.

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pwnstigator
However, experts believe that "petrichor" will not replace "October rain" as a
term of endearment.

~~~
dylanz
I've never heard the term "October rain" before, but had to look it up. Quite
a few poems with that title it seems. I thought you were referring to the Gun
N' Roses song "November Rain" there for a second :)

