We use our senses while riding, of course, but one of my favorites is the sense of smell.
Right now, the smell of late-season grilling greets my nose on the commute home. Freshly-cut grass is a favorite no matter the season. Sometimes, the unpleasant diesel and kerosene fumes, near the airport. Or the cigarette (or cannabis) smoke from a car a few yards ahead of me.
Soon will come the scent of dry leaves, wood-burning stoves, and dry, hard air.