Petrichor...
Sensing the Rain
“The smell of wet earth after a summer rain is one of life's simplest pleasures."
While many areas around the world suffer from insanely high temperatures, here in the UK we are experiencing heavy rain showers with temperatures struggling to rise above 20Deg. Over recent weeks this has given rise to petrichor - that wonderful sense and smell we experience just before and during a storm.
Petrichor triggers our senses and evokes a sense of calm, freshness, and a re-connection to the environment.
The aroma of petrichor can remind us of the life-sustaining properties of rain, promoting a sense of well-being and reinforcing our connection to the natural world. It may awaken our senses, inspire a desire to be outdoors, and encourage us to appreciate and engage with the environment around us. Ultimately, petrichor can contribute to our overall biophilic experience, deepening our connection to nature through experiencing the earthy scents.
How could we, should we? bring this wonderful feeling within our buildings in which we live work and play?
… notes from climate novel in writing
As the scorching sun beat down relentlessly, the town had fallen into a state of despair. For weeks, a merciless drought and insanely high temperatures had left the land cracked and barren, and a longing for relief. But on this particular day, a shift in the wind brought a glimmer of hope—a change was on the horizon.
The air grew heavy, pregnant with anticipation, as dark clouds gathered on the horizon. A strong scent of petrichor wafted through the town, signaling the imminent arrival of rain. Whispers spread through the streets, carrying a mix of excitement and skepticism. Had many forgotten what rain felt like, how it could wash away the tiredness that had settled in their hearts.
As the storm neared, the atmosphere transformed. The once-scorching air turned cool and crisp, invigorating the senses. The wind, once a relentless oppressor, now danced playfully, rustling leaves and gently tousling hair. The distant rumble of thunder echoed like a symphony, growing louder with each passing moment.
Thomas, who had witnessed countless storms in his lifetime, stood on the porch of his weathered cottage. Wrinkles etched deep into his face told stories of years gone by, and his eyes sparkled with nostalgia as he sensed the petrihor of the approaching storm. He could feel it in his bones—an impending release from the drought’s grip. He felt alive.
As the first raindrops fell, they landed softly on the parched earth, like delicate kisses. Each drop brought life back to the desolate ground, coaxing tiny green shoots to emerge from the cracks. Thomas closed his eyes as the raindrops cascaded around him.
Hours later, as the storm subsided, a calm settled over the town. The air had been refreshed, the land rejuvenated, and a renewed sense of hope filled hearts .
Zoom Regenerative 57 on 25th July 2023
Event - How do we bring Regenerative from niche to mainstream? How do we communicate complexity better? How do we recalibrate our roles to the new challenges ahead? An interactive ZR with Jo Petroni.
Science behind Petrichor (with a little AI help)
The word "petrichor" is derived from two Greek words: "petra," which means "stone," and "ichor," which in Greek mythology refers to the ethereal fluid that flows in the veins of the gods. The term was coined by two Australian researchers, Isabel Joy Bear and Richard G. Thomas, in a 1964 Nature journal.
Petrichor is the pleasant, earthy smell that often accompanies the first rain after a dry period. The science behind petrichor involves a combination of factors, including chemical and physical processes.
Volatile compounds in the environment: Before the rain, the Earth's surface becomes dry due to hot weather or drought conditions. During this time, plants release certain volatile compounds into the air. These compounds are produced by plants, bacteria, and fungi. Some of the common compounds include oils, geosmin, and various terpenes.
Absorption on soil and rocks: When the rain starts, the water droplets carry these volatile compounds from the air to the ground. They are then absorbed into porous surfaces, such as soil, rocks, and clay.
Interaction with geosmin: One of the key compounds responsible for the petrichor scent is geosmin. Geosmin is a bicyclic alcohol produced by certain soil-dwelling bacteria and actinobacteria. This compound has a strong, earthy odor and is highly volatile.
Aerosolization: When raindrops hit the ground, they create small air bubbles on the surface. These bubbles can trap geosmin and other volatile compounds absorbed in the soil. As the raindrops burst the bubbles, the aerosolized mixture is released into the air.
Spreading of the scent: The aerosolized compounds are then carried upwards by the rain's splashes and the wind, spreading the distinct petrichor smell through the surrounding environment.
Our human sense of smell is incredibly sensitive to certain scents, and even very low concentrations of these compounds can be detected, which is why we can perceive the delightful petrichor scent after a fresh rainfall, sometimes before.
Petrichor is not only a pleasant olfactory experience for us but also serves as an environmental cue. For example, it can signal to certain animals and plants that water is available, which may trigger specific behaviors like emergence, mating, or germination.