Are you one of the many who notice a distinct smell in the air after it rains? According to science, it is often associated with spring, as the smell of fresh-cut grass is linked with summer.
We usually find this link in many poetry and in a lot of inspirational lists of sayings and quotes about being happy or reasons for being happy.
According to reports, the scientific name for this particular smell is "petrichor," originally named by two Australian scientists in the 1960s. Petrichor actually comes from the earth's moistening. But what's causing the scent?
Apparently, the smells we link with rainstorms can be brought by several things. One of the more pleasant smells after the rain, the one we frequently observe in the woods, as science explains, is caused by bacteria, known as "actinomycetes."
What is Actinomycetes?
This is a type of filamentous microbes that grow in soil when there are damp or warm conditions. When the soil has dried out, the bacteria then produce some spores in the soil.
The rainfall's wetness and force kick up these tiny spores into the air where the moisture following rainfall functions as an aerosol like the one acting in the air freshener.
The moist air easily takes the spores to us, and thus, we breathe them. Such spores have that distinctive earthy smell we typically link with rain.
The so-called 'rain smell' is brought by a chemical the germs, also known as "geosmin," which is emitted by the microbes as they die.
Geosmin is a type of alcohol molecule with an extremely strong smell. The bacteria are very typical and can be found in areas anywhere in the world, accounting for the generality of this sweet 'after-the-rain' smell.
Other Smells We Breathe After Each Rain
Another type of smell is brought by the rain's acidity. Due to the chemicals in the atmosphere, rainfall can possibly become acidic, specifically in urban areas.
In terms of contact with chemicals or organic debris on the ground, they can lead to some specifically aromatic reaction.
It breaks the soil apart and discharges minerals stuck inside, which respond with chemicals like gasoline, resulting in a much stronger smell.
Such reactions commonly generate more unpleasant smells compared to bacteria spores, which is the reason after-the-rain aroma is not always a pleasant one.
Another smell we breathe after the rain is coming from volatile oils released by plants and trees. Such oil then collects on the surface like rocks.
After-the-Rain Scent similar to Bacteria Pores
The rain then reacts with the oil coming from the rocks and takes it as a gas through the air. This scent is similar to bacteria spores that we more often than not consider as pleasant and fresh smell. This has even been reportedly bottled and sold for its sweet-smelling qualities.
These are only a few common smells we notice, although there are all sorts of other aromas too, after it rains. There are lots of aromatic objects that the rain's moisture and impact can kindle.
More so, the moist atmosphere after rainfall is specifically good at bringing these particles through the air. Thus, the next time you talk about an after-the-rain aroma with a friend, you may mean a single thing while he or she is thinking of something else. Both of you might agree, though, that the air has a much stronger smell to it following a good rain.
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