

Slow-motion video of raindrops reveals how rain gets its distinctive smell - prateekj
http://www.washingtonpost.com/news/speaking-of-science/wp/2015/01/16/slow-mo-video-of-raindrops-reveals-how-rain-gets-its-distinctive-smell/

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colept
Wouldn't this provide some evidence for the theory that going into the rain
would make you more susceptible to get sick? The range might be limited to
close quarters but what about the residual germs and/or viruses that might
remain and be aerated again by other raindrops?

It would amaze me to see the aerated particles over time to see if they can be
aerated again.

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dj-wonk
Your logic makes sense.

Two things.

1\. In my experience, stories about rain being associated with getting sick,
tend to be more related to being cold and wet. We could go on for hours about
"folk science" about how cold weather causes sickness. Cold weather is rightly
correlated with flu season, reduced levels of vitamin D, and diminished
physical activity, all of which probably have strong links to sickness.

2\. Your choice of baseline comparison is probably key here. Is going out in
the rain "safer" than staying indoors? Staying indoors in a poorly ventilated
office building?

From what I can tell, general wisdom today seems to be: unless your immune
system is compromised, or you have strong allergic reactions (such as hay-
fever), or you live in polluted area, or it is a high ozone day, it is a good
to get some exposure to outside air, including the natural germs floating
around in it. (Gosh, when I started writing that sentence, I didn't realize
how many caveats I would need!)

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dnautics
the title for the post article is unfortunate, rain gets its distinctive smell
largely from geosmin:
[https://en.wikipedia.org/wiki/Geosmin](https://en.wikipedia.org/wiki/Geosmin)

this is just the mechanism by which rain's smell is particularly _intense_.

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trentmb
I get so excited when it's supposed to rain, especially in the summer.

That ozone smell before, and that earthy smell (which I now now is geosmin)
after. It's so awesome.

I wish I could bottle it and do bumps to my noses content.

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forgotpasswd3x
> I wish I could bottle it and do bumps to my noses content.

I never knew I wanted this before, but now it's all I want. I'd absolutely buy
a bottle of that.

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akx
I knew I had this link in my bookmarks for a reason...

[http://www.demeterfragrance.com/704174/products/Rain.html](http://www.demeterfragrance.com/704174/products/Rain.html)

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cossatot
I wonder if this is the same mechanisms that releases smells from your hair
when you first put your head in the shower and have some strong or notable
scents in your hair. One of my favorite parts about coming home from camping
trips is showering and smelling the campfire smell again when my hair gets
wet.

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thomasahle
I'm impressed with how well they make their research public. This could have
just been some people with a high speed camera and some mathematical models
answering a curiosity and releasing a paper. Like this they present it in a
way that even primary schoolers can understand, and even manage to link it to
current affairs in the end. 👍

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andrewstuart2
> “Until now, people didn’t know that aerosols could be generated from
> raindrops on soil,” Youngsoo Joung, a postdoctoral student who worked on the
> research, said in a statement.

Um, wat? I can't count the number of times I've seen a raindrop or water in
general kick up dust, which is also an aerosol: a colloidal suspension of
particles dispersed in air or gas. So I find this statement a little
surprising.

Sure, the mechanism of bubbles inside a raindrop may be new, but rain kicking
stuff into the atmosphere is pretty unsurprising. In AZ, I know several
"desert field trips" I went on as a child had us pick Creosote leaves, rub the
leaves, and smell the oils released. Voila, rain smell (at least if you're
around creosote plants).

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talalbaweja
Ever walked barefoot on the grass early in the morning when it is soaked with
dew. I think there is a lot going on their to give a very distinct smell,
which we can all relate to.

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rbobby
Very nice... and right at the end they ruined it: "rainfall may spread
diseases like e.coli".

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spaceshipdev
...and they do say "A day without Wine is a day without Sunshine"

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thenovelnomad
Also, how public bathrooms get their distinctive smell...

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SchizoDuckie
That is so cool :) best smell in the world

