7 ms·
Petrichor: why does rain smell so good?
- _nhynes 7y agoSeems reasonable. If I put on my ad-hoc explanation hat, since geoosmin is produced when Streptomyces die, tasting it in water might indicate that the ecosystem is under stress. Conversely, smelling it in the air suggests that the soil ecology is healthy -> good place to plant crops.
- dang 7y agoI feel like there have been many discussions of this over the years but found only one, from 2013: https://news.ycombinator.com/item?id=5583575 https://news.ycombinator.com/item?id=5583575
- deleted 7y ago[deleted]
- namirez 7y ago"If not today then soon, gray clouds will gather. Let it come so I might hear leaf splats, watch the wet blotch, taste on my tongue, feel on my face the pentecost of petrichor." --Above the Waterfall, Ron Rash
- combatentropy 7y agoAnother interesting chemical interaction is how lightning causes rain to be more nourishing to plants. It separates the nitrogen from the air, which combines with oxygen to form nitrogen dioxide. "Nitrogen dioxide dissolves in water, creating nitric acid, which forms nitrates. The nitrates fall to the ground in raindrops and seep into the soil in a form that can be absorbed by plants." --- https://wxguys.ssec.wisc.edu/2018/07/09/lightning/ https://wxguys.ssec.wisc.edu/2018/07/09/lightning/
- getoj 7y agoThis has been folk knowledge in Japan for thousands of years. Rice paddies are traditionally planted in places with a propensity to lightning storms, a fact so well known that it reduces land values in suburbs built on old paddy land (there are other downsides to that land, but this is one). Also, the word for "thunder" (雷) is written as "rain" (雨) over a "rice paddy" (田), and the word for "lightning" (稲妻) is "rice plant's (稲) wife (妻)".
- matchbin 7y agoOff topic but do you have a resource for your second paragraph? I find this etymology fascinating!
- nereye 7y agoNot sure if this is what you had in mind, but, for example: rain - https://ja.wikipedia.org/wiki/雨 https://ja.wikipedia.org/wiki/雨 field - https://ja.wikipedia.org/wiki/田 https://ja.wikipedia.org/wiki/田 thunder - https://ja.wikipedia.org/wiki/雷 https://ja.wikipedia.org/wiki/雷 rice - https://ja.wikipedia.org/wiki/稲 https://ja.wikipedia.org/wiki/稲 wife - https://ja.wikipedia.org/wiki/妻 https://ja.wikipedia.org/wiki/妻 lightning - http://nihongo.monash.edu/cgi-bin/wwwjdic?1MDJ%B0%F0%BA%CA http://nihongo.monash.edu/cgi-bin/wwwjdic?1MDJ%B0%F0%BA%CA
- yorwba 7y agoThose would probably be more helpful as Wiktionary links: rain - https://en.wiktionary.org/wiki/雨 https://en.wiktionary.org/wiki/雨 field - https://en.wiktionary.org/wiki/田 https://en.wiktionary.org/wiki/田 thunder - https://en.wiktionary.org/wiki/雷 https://en.wiktionary.org/wiki/雷 Note that the "glyph origin" section describes 雷 as an ancient simplification of the phono-semantic compound 靁, where 畾 indicates the pronunciation. Any relation to rice paddies is probably a post-hoc rationalization. rice - https://en.wiktionary.org/wiki/稲 https://en.wiktionary.org/wiki/稲 wife - https://en.wiktionary.org/wiki/妻 https://en.wiktionary.org/wiki/妻 lightning - https://en.wiktionary.org/wiki/稲妻 https://en.wiktionary.org/wiki/稲妻
- 7y ago
- pjc50 7y agoIn the modern era, nitrogen dioxide is a pollutant; it's also produced by most combustion processes. Too much of it results in "acid rain" which is harmful to plants. Can't have too much or too little.
- qqn 7y agoLol this reminds me of what my dietitian cousin is known to say: everything in moderation... including moderation ; )
- atomi 7y agoI think it's common knowledge that rain water is excellent for plants. But I don't think many people know the mechanism of action. Although I suspected water somehow picked up nitrogen in the air, I wasn't aware exactly how. Thank you for sharing!
- kickbutt22 7y agoI read a book that talked about how negative ion environments make you feel better. I believe Nikola Tesla even wrote about this while experimenting with some device that created negative ions. Places like niagara falls and natural water-related environments (waterfalls, riversides, beaches) have some of the highest negative ion concentrations while air conditioned environments have some of the lowest.
- fitzroy 7y agoAbout 30 years ago I saw “The Five Doctors” (the 25th anniversary episode of Doctor Who). Ever since then I’ve believed the smell, and associated feeling, were due to “positive ions”. In all that time I’ve never fact checked that line, but I think about it every time I notice the smell after a storm. From the screenplay: TURLOUGH: It's marvellous here. I feel so calm and relaxed. DOCTOR 5: It's the high bombardment of positive ions. TEGAN: It's like Earth after a thunderstorm. DOCTOR 5: Same cause and reason.
- oluckyman 7y agoMy fave song about petrichor is by Paul Kelly: https://youtu.be/A9_qkTeMlGk https://youtu.be/A9_qkTeMlGk
- etxm 7y agoThis is one of my favorite words. The article is a good summary of what produces the smell, but why do humans tend to find it appealing? Is it wired into our collective subconscious?
- buzzert 7y agoNothing beats the smell of the Sonoran desert during the rain, thanks to a special plant called the Creosote bush. Rain is also rare enough so everyone from the region grows to appreciate it a lot.
- davidw 7y agoI was going to say... having grown up in western Oregon, I think rain smells good when it's not an everyday occurrence for months on end!
- trypt 7y agoThe best rain smell is in the southwestern US like New Mexico and Arizona. The creosote bushes all release their scent into the air and it's the most refreshing thing ever. It's worth visiting the area for a few weeks during Monsoon season just to get a chance at experiencing this. You have to be near the desert though, not in an urban area.
- jandrewrogers 7y agoThe western US desert in the rain definitely has a lovely smell to it that is almost therapeutic. It is interesting how distinctive the smell is of various wilderness areas of the US, especially after rain. As someone who grew up in the rural Pacific Northwest of the US as a child and moved back there much later in life, I realized that I find the unique smell of the Cascade mountains to be irrationally relaxing. I've always wondered what, specifically, makes me respond to it that way.
- SamReidHughes 7y agoFor what it's worth, I grew up in Pennsylvania, and when visiting home, I found the keystone shaped state route number signs irrationally relaxing. I'd guess the reason is, you remember the smell from your childhood.
- fyfy18 7y agoI haven't been there so I can't compare, but my favourite is in Lithuania where the country has a large nunber of pine forests. After the rain you get a lovely smell of pine in the air. Even on the outskirts of the city and the airport you can smell it, not just far away. I remember once I travelled here from Italy, and just stepping off the plane I though "wow it smells so good".
- qqn 7y agoThe pine scent may actually be "terpenes": "Often the plant chemicals that smell pleasant are produced in leaf hairs... and the rain may damage these, releasing the compounds."
- etaioinshrdlu 7y agoI am so bummed that Geosmin is so expensive. Almost $600 for 10 milligrams! https://www.sigmaaldrich.com/catalog/product/sigma/uc18?lang=en®ion=US https://www.sigmaaldrich.com/catalog/product/sigma/uc18?lang...
- IshKebab 7y agoI've always wondered about this smell. What about the small of freshly cut grass?
- PaulAJ 7y agoI have an old book by Magnus Pyke called "Butter Side Up" which has a chapter on this. The bit about Streptomyces wasn't known then though. https://en.wikipedia.org/wiki/Magnus_Pyke https://en.wikipedia.org/wiki/Magnus_Pyke https://www.amazon.co.uk/Butter-Side-Up-Delights-Science/dp/0719532981 https://www.amazon.co.uk/Butter-Side-Up-Delights-Science/dp/...
- noir-york 7y agoIf you find the article interesting you will most likely want to enjoy it to Ludovico Einaudi's sublime Petricor piece (modern violin / cello / piano). Its a beautiful piece of music. https://open.spotify.com/track/4XWqS8UGO5x4ClB2yH0nbW?si=EwzxJpq6R_KvSN8X11tEVQ https://open.spotify.com/track/4XWqS8UGO5x4ClB2yH0nbW?si=Ewz... And congrats on the good taste, even if I say so myself.
- lloydatkinson 7y agoGood????? That smell is absolutely disgusting and I have to actively avoid breathing through my nose.