ABOVE: Hot, arid conditions are ideal for creating petrichor after a brief rain.
© ISTOCK.COM, PANYA RIAMTHAISONG
After long periods of drought or heat, even a brief rain shower brings a welcome respite while filling the air with a rich, earthy scent. The rain doesn’t actually provide any scent itself; rather, the impact of the drops on rocks and soil splashes an oily, bacteria-made substance into the air, creating that distinctive aroma now known by the name of petrichor.
But while scientists and perfumers have been familiar with this scent since the late 1800s, it wasn’t properly defined until 1964 when Isabel “Joy” Bear and Richard Thomas, chemists at Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO), published “Nature of Argillaceous Odour” in Nature.
“Argillaceous” is a geological term meaning that something contains or resembles clay, but it didn’t seem to be the best fit, as the duo came to realize ...
