After the Rain is the title of a classic, evocative short piece by John Coltrane and also is one of the most universally loved scents. There is a difference between before and after the rain scents. Before is caused by an increase in ozone in combination with the many trace elements released into the air from all the disruption caused by winds and other environmental factors. After the rain has a very pleasant earthy element, caused by the release of Actinomycetes bacteria spores in the earth, carried by moisture and wind through the air to our noses. Those are the bacteria responsible for the breakdown of organic materials into rich soil, and have recently been made into antibiotics. It is speculated that inhaling them has a healthful effect. Certainly it does psychologically, most people find the smell of rain and moist earth to be fundamentally pleasing. If you add the elements of wet grass, florals, fruit or woods, you have a perfume. There have been attempts to reproduce the exact scent of rain but even with head-space technology it hasn't been successfully accomplished. There are so many unidentifiable trace elements involved and it is such a changeable experience it can't be reproduced artificially. There have been some scents inspired by rain, made up of disparate elements combining to give a connection to that primal feeling. The other day I tried a couple of Demeter Fragrances, Thunderstorm and Dirt, one on each wrist, to see if together they would evoke a good rain experience (they do have a Rain fragrance but I haven't tried it yet). The immediate effect was a very good copy of the actual sensations of those elements, but then when (my) skin came through I got a much sweeter tone and only a few fragile wisps of the sense of impending fullness in the air remained of Thunderstorm, though very enjoyable while it lasted. The musky scent of Dirt was very earthy and was more successful at staying true to form. I like the idea of the Demeter line, which is to offer very affordable though traditionally made fragrances that use natural elements, designed to evoke pleasant memories. They have a very sheer quality and must be reapplied frequently to keep the effect. That can be fine in the city or at work, if you don't want to hit others over the head with your perfume, or for a portable mood enhancement.
Above, Japanese woodblock print
Utagawa HIROSHIGE 1797–1858
Sudden Rain at Shono c.1831-4
Allen Memorial Art Museum, Oberlin College
Mary A. Ainsworth Bequest, 1950