You know that distinctive smell you get when the first rain shower after a long, hot, dry spell hits asphalt?
Does anyone know what compound(s) is/are responsible for it, and why they only seem to get released in these circumstances? I love this smell, but you don’t get to experience it very often!
http://www.mit.edu/~goodmanj/madsci/897083302.Ch.r.html
This page talks about the smell:
"So what is that smell produced by wet concrete? I honestly don’t know, but It’s similar to the smell of freshly-mixed concrete, and I’ve also smelled it when carrying out the reaction
Ca(OH)2 + CO2 -> CaCO3 + H2O
Some rocks (limestone?) also smell like this when wet. I suspect the smell has something to do with calcium; either small particles are released into the air which enter your nose, or there’s some sort of gaseous calcium-containing molecule produced by interaction between carbon dioxide, water, and a calcium compound (though that seems unlikely.) "
I’ve always been led to believe that the smell is from the accumulation of oil, gasoline, dirt, pulverized rubber, and whatever has fallen on the road since it last rained. When it does finally rain, all those nasty smells are kicked into the air for you to sniff.
If it rains hard, or has rained recently, you won’t get that smell because all the oils and crap will have already washed away.
I love that smell. My nose tells me it’s motor oil and dust.
I always heard it was bacteria spores.
No, that’s the kind of “rain in your garden” smell.
This is what I’m talking about (from that site)…
So, I guess it’s acid rain reacting with petrochemicals… Yum!
Yyeeeaaaahh! That’s what I’m talkin’ about! Whooooo!
Some say you shouldn’t pet the sweaty chemicals. Durn fools.
You smell that? Do you smell that? …Napalm, son. Nothing else in the world smells like that. I love the smell of napalm in the morning…The smell, you know that gasoline smell, the whole hill. Smelled like…victory.
I thought I was the only one who liked that smell. Reminds me of playing street hockey when it would start to drizzle. Those last few desperate minutes of playing before you had to quit were the childhood sublimity equivalent of those last few minutes of sleep before the real buzzer goes off…