Petrichor was first described in by mineralogists Isabel Joy Bear and R. As they defined it, it occurs when airborne molecules from decomposing plant or animal matter become attached to mineral or clay surfaces.
During a dry spell, these molecules chemically recombine with other elements on a rock's surface. Then when the rains came, the redolent combination of fatty acids, alcohols and hydrocarbons is released. This is the aroma of geosmin, a metabolic by-product of bacteria or blue-green algae. Geosmin can be a comforting call to gardeners eager to dig in the dirt, but it's less beloved when it contaminates wine or drinking water, leaving a damp stench. Why an aroma at all? All these chemicals stirred up by the weather can carry messages.
Some biologists suspect that petrichor running into waterways acts as a cue to freshwater fish, signaling spawning time. Microbiologist Keith Chater at the John Innes Center in England has proposed that geosmin's fragrance may be a beacon, helping camels find their way to desert oases.
In return, the bacteria that produce geosmin use the camels as carriers for their spores. But do these smells send meaningful messages to humans? Anthropologist Diana Young at the University of Queensland has studied the traditions of aboriginal people in Australia's Western Desert.
There, the first rains before wet wintry and summer months are an important event, mingling the sweet odors of damp gum leaf oils, eucalyptus, animal waste and dust. The rains bring game such as kangaroo and emu, quench thirst and transform the red desert into a verdant landscape. Young says that to these people the smell of rain is linked to the color green, a connection she calls "cultural synesthesia. The odor is believed to be protective and cleansing, linking present generations to their ancestors.
In an era when radio coverage was spotty, especially in the country, the neighborhood practically thought of him as a medicine man. Now scientists have discovered why people can smell the storms so far away.
A sensitive snout is smelling ozone, petrichor and geosmin; in other words, the nose smells oxygen, the debris that raindrops kick up and wet bacteria. First comes the ozone, the oxygen fried by lightening that changes its chemistry for O2 to O3. This has a sweet, pungent zing and winds carry it down from the upper atmosphere to your waiting nose.
If you smell a lot of that—look out! Then comes the raindrops. Scientists discovered that water drops hitting surfaces like soil or leaves knock particles up in the air. A raindrop hitting an uneven surface traps bubbles of air that shoot upwards and burst from the top of the water droplet like fizz in a champagne glass.
These bubbles can float long distances before they pop and you can smell the pollens, dirt, oils or city scum. Finally, the wet soil triggers the bacteria or blue-green algae to release geosmin, that great earthy smell so loved by gardeners.
Drops of water spray aerosols into the air that you can smell downwind. Source: Wikipedia. How he tracked those squirrels through the woods remains a mystery. What does each one mean. One rain drops hitting a puddle and creating rings. Two rain drops hitting a puddle and creating bubbles on the surface of the puddle.
Thank You , Mark. One day at work She said I smell snow. We all laughed, me not so hard I can smell rain. As we were leaving that day she says this was on a Thursday I'll see you all Monday. We ask why. It'll last the week-end" It did snow that night, but it was Tuesday before we went back to work, ice covered roads!
My daughter and I are severely affected by the changes in Barometric pressure. In the middle of a pleasant sunny day, we separate even by county suddenly feel incredibly tired, almost a drunken sleepiness that overpowers and makes getting through the rest of the day difficult at best. The strangest thing is that once the approaching weather has arrived, we are no longer affected any more than the next person, it is only the approach that is almost debilitating.
Yes, I can smell the rain coming, and sometimes the snow, too. I could always do that. I knew that if the scent on the wind was sharp and wet, it meant rain in the summer and snow in the fall and winter, and maybe in the spring, too. In addition, I get some really nasty sinus headaches when the front edge of a pressure front goes through my area.
It feels like my face is being squeezed, and lasts about an hour. It's extremely unpleasant but there is no remedy for it because it is caused by a change in barometric pressure. Just have to sit it out. Odd phenomenon but since smelled the rain when working as a lifeguard at Drops of water hitting the ground cause geosmin to be released into the air , making it much more abundant after a rain shower. Isabel Bear and RG Thomas, the researchers who first named the scent petrichor, found that as early as the s it was being captured to sell as a scent called "matti ka attar" in Uttar Pradesh, India.
Now, geosmin is becoming more common as a perfume ingredient. Yet we also have an odd relationship with geosmin - while we are drawn to its scent, many of us dislike its taste. Even though it is not toxic to humans, the tiniest amount can put people off mineral water or wine when it is present.
Petrichor: The term:. The word was coined from Greek petros, meaning "stone", and ichor, meaning "the fluid that flows in the veins of the gods". According to Prof Nielsen, research also indicates that geosmin could be related to terpenes - the source of scent in many plants. Very dry periods may also slow down plant metabolism, with renewed rainfall giving it a kick start and causing plants to release a pleasant scent.
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