While Natasha Bedingfield sings out loud feel the rain, the researchers from MIT encourage smelling the rain. The secret to why rain smells so fresh has been revealed. Recently, MIT researchers uncover the reason why rain’s earthly smell is so unique.
Massachusetts Institute of Technology, commonly known as MIT, decided to embark on a rain journey in order to prove rain’s extraordinary smell. The mechanical engineers were intrigued by the fact that everyone knew that rain had a smell, but no one actually found out how the smell extends throughout the atmosphere. They claim that rain is such a common phenomenon, still no researcher thought of the idea of discovering rain’s mechanism.
For some decades now, it has been discovered that rain’s peculiar smell comes from plant oils. These oils are only secreted by certain plants when the season is dry. Keeping that in mind, researchers wanted to know how those oils are spread around the air.
In order to detect rain’s mechanism of perfuming the world around, researchers placed high-speed cameras. Then, MIT mechanics looked at rain drops falling with slow motion techniques. That is when they observed that each rain drop encapsulates small air bubbles while descending from the sky. The phenomenon resembles with a glass of sparkling water.
However, those bubbles find their way to the surface. After capturing the air, the rain drop releases the bubbles in the form of aerosols when it hits the ground. That is when the smell is produced. This above mechanism also clears up why the smell is more intense at the beginning of the rain phenomenon.
Rain drop’s speed and the permeability status of the contact surface produce large amounts of aerosols. Researchers took those variables into consideration in order to develop a formula which calculates the amount of aerosols released into the atmosphere. Other factors such as rain’s velocity or the structure of the contact surface were also taken into account.
Moreover, MIT researchers saw that those aerosols floated around the atmosphere containing bacteria, microbes, viruses released from the contact surface, such as soil. This mechanism explains how bacteria travel from the environment to the human body. Substances or viruses spread around the soil can generate into aerosols and reach humans.
In order to demonstrate their findings, MIT researchers used 16 soil samples, 12 materials into a total of 28 types of contact surfaces. The experiment was repeated 600 times in order to show that more aerosols are released during light rains rather than heavier ones.
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