[Lee Stewart]

Water doesn't smell like anything, so why does rain produce a pleasant aroma after it falls? Well, it's because of a molecule called geosmin, created by soil-dwelling bacteria. When rain falls, it creates air pockets, which contain small amounts of geosmin. The rain traps and then releases these air pockets, dispersing geosmin into the air, where it's free to travel to human sniffers. The smell of rain even has a name: 'Petrichor.'