Why does cold air smell?
Who else is ready for scenes like this? | Photo Credit: Forsaken Fotos

As the mornings get colder and colder, you may notice a distinct smell in the air upon walking out the door. The aroma is perhaps most memorably recalled in the ski movie classic, Aspen Extreme when its protagonist, TJ Burke takes a deep breath of the crisp autumn air and asks his lover, Robin Hand, “smell that? Winter’s coming.”

Related: 5 Ski Resorts With Reliable Early Season Snow

It’s a smell that brings back memories of sitting on a chairlift getting blanketed in snow. But what exactly accounts for this weird olfactory reaction to snow and cold? After all, it’s not like a snowball is the equivalent scent source of say, a flower. So how does our nose pickup on winter’s scent?

Science has a few explanations, all of which are worthy of exploring as we delve into the reasons why we love the smell of winter.

The Chemistry Of Cold

The main reason humans can pick up on the smell of winter is not because there is a new scent coming into our olfactory system but actually, quite the opposite. As temps begin to cool in the fall, air molecules including oxygen, hydrogen, nitrogen, methane, and others begin to slow down. This means that scents do not travel as far as they do in warmer temperatures. So as temps cool, air actually loses its potential to carry various aromas. This creates a void for our olfactory system and allows our noses to pick up on subtle scents, including humidity.


One of the most prevalent yet subtle scents in the natural world is that of H2O. The smell of water, however subtle, is ever present on a snowy day. Scientists believe such humidity combined with the lack of other scents competing for sensory attention creates the smell of snow as we know it. But the smell of snow wouldn’t be complete without the final nervous system reaction, which is in fact, not technically connected to the olfactory system at all.

Trigeminal Nerve

Once our noses have entered a cold environment, our nervous system responds by activating the Trigeminal Nerve. This nerve, which is not directly considered a part of the olfactory system, gives us a sort of sensory counterbalance to what we would otherwise consider an atmosphere full of pungent smells. Still not sure what we’re talking about? That’s because the Trigeminal Nerve is the most complex nerve in our body and its relationship between taste, smell, and sight still remains somewhat of a mystery. Besides cold, the Trigeminal Nerve is also activated by the scent and taste of mint and wasabi. The olfactory reaction is often described as subtle yet visceral.

So there you have it. Chemistry, humidity, and the human nervous system all work in tandem to literally create an aroma for something that is otherwise, not smelly at all.

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