It’s been a rather wet and cloud-filled summer for B.C.’s sunny Southern Interior.
While the South Okanagan — with its well-known bounty of fruit and wine — isn’t a desert, it has semi-arid shrubland, which is close enough.
The study from the University of Arizona says the smell of desert rain can not only lead to euphoria, but it may also have additional health benefits, as plants release oils and other chemicals after a good soaking.
“The Sonoran Desert flora is one of the richest in the world in plants that emit fragrant volatile oils, and many of those fragrances confer stress-reducing health benefits to humans, wildlife and the plants themselves,” said Gary Nabhan, a research social scientist.
The Sonoran Desert stretches from northwest Mexico into the southwest U.S., but, contrary to popular belief, it does not stretch north to Canada.
Further, the South Okanagan is also not part of the Great Basin Desert that encompasses most of Nevada, though it does share some plant and animal species with its southern neighbour.
Deemed distinct from those two deserts, the South Okanagan is still a hotspot, and there’s no arguing that when rain hits the semi-arid region, it does smell good.
“After a heavy rainfall in our desert environment here in the South Okanagan, you will definitely smell the scent of sage,” said Jayme Friedt, managing director of the Osoyoos Desert Centre.
Friedt says the area is home to three to four different types of sagebrush, which will be the dominant scent lingering in the air after rain.
“It smells amazing,” said Friedt. “It’s like a turkey dinner, I suppose, though our sagebrush that grows here isn’t necessarily edible. But it does have that delicious sage smell.”
Friedt noted there are also plants that bloom at different times, leading to a variety of fragrances and sights to see.
According to the University of Arizona, Nabhan is the lead author of two new studies that explain how organic compounds that evolved to protect plants from solar radiation, heat waves, drought stress and predatory animals may also have health benefits for humans.
The study focuses on the Sonoran Desert and its monsoon season, which generally runs from June 15 to Sept. 30. About half of the region’s average annual rainfall occurs over the course of those three-and-a-half months.
The university says Nabhan and his co-authors identified 115 volatile organic compounds in 60 species of plants in the Sonoran Desert that are released immediately before, during and after rain. Of these, 15 have been shown in past studies to offer tangible health benefits.
“The fragrant volatile organic compounds from desert plants may in many ways contribute to improving sleep patterns, stabilizing emotional hormones, enhancing digestion, heightening mental clarity and reducing depression or anxiety,” Nabhan said.
“Their accumulation in the atmosphere immediately above desert vegetation is what causes the smell of rain that many people report.”
Nabhan also said many desert plants produce more volatile oils during the summer to protect themselves from harsh conditions.
“The production of the oily compounds is happening during the extreme droughts and severe heat waves, but they remain on the leaves until we get the onset of the summer rains,” Nabhan said.
“We used to think that during the summer rains, those oily and gummy substances were washed off and into the air, but now there’s some evidence that with humidity and the fierce winds that we get with the onset of the rain, they’re released into the atmosphere even before the rain actually falls and contribute to that incredible surge of anticipation that you feel right before the first raindrop of a thunderstorm.
“From there, they travel into our lungs and into our bloodstream within minutes.”
Notably, the Osoyoos Desert Centre has a 1.5-kilometre boardwalk that was recently built. It meanders through acres of shrubland that the centre takes care of.
“It’s a beautiful walk,” said Friedt. “You’re really immersed in the habitat and there are all sorts of critters that live out there.
“It’s just a great way to get to know the environment.”