8 September 2019 What Does Sea Ice Smell Like?

What Does Sea Ice Smell Like?

Frazil ice forms on the Arctic Ocean as temperatures drop. Photo by Bill Schmoker (PolarTREC 2015), Courtesy of ARCUS.

"It smells like fall," I exclaimed to a friend recently. They agreed with joy. This summer has been so unusual here in Homer - hot, sunny, smoky. The smells have been different, unexpected. But after last week's rains, it smells refreshingly of fall. A beautiful medley of what I suppose is dying leaves and over-ripe berries. I'm not sure exactly what all the components of this fragrance are, but it is decidedly the smell of autumn in Homer.

One recent study calculated that humans can sense over 1 trillion different olfactory stimuli. This is impressive, and way more than what most people assume we can smell. There are actually some super interesting historical, cultural, and religious reasons why humans were long-considered to have poor senses of smell. John P. McGann explains possible origins of this myth in an interview and Science article. Most of us recognize that smells can trigger memories and emotions, and there is a large body of research that supports this human experience. Studies, such as this one, have demonstrated that exposure to pleasant, familiar odors can decreases stress and negative mood.

A young friend and I hike in cottonwoods and spruce trees at the base of Grewingk Glacier, Alaska. Photo by my partner, Nathan Main, 2019.

Cottonwood (balsam, poplar) is a smell that reminds me of coming home. Not home itself, but specifically the act of coming home. Both the Anchorage, Alaska and Homer, Alaska airports must have lots of young cottonwoods growing nearby. When I step onto the tarmac to board the small plane from Anchorage to Homer, the scent of cottonwoods (mixed with a tinge of jet fuel) washes over me. Arriving in Homer, there is the smell again! It evokes relief, happiness, a sense of safety, excitement, and ease. It is the smell of coming home. Nostalgia fulfilled. Cottonwoods also abound in some of my favorite places to hike and camp, layering more positive emotions atop that sense of coming home. When I find cottonwood away from home, I breathe it deeply and all those emotions wash over me. I roll the sticky leafbuds between my fingers, releasing more of their precious scent. It will stay on my hands all day, reminding me of what it feels like to come home.

I bought a small container of cottonwood balm yesterday to take with me on the Federov. I imagine there will be a time, perhaps many, when we have been at sea for a while and the isolation and dark and cold will overcome me. I will feel farther from home than ever. But I know that with the simple twist of a lid and a sniff, I can evoke that sense of coming home. I just hope it makes it through customs -- that's why I bought a commercial product rather than just stuffing some cottonwood leaves in a jar.

As I embark to the sea ice and Arctic Ocean, I wonder what smells will come to define this trip. I imagine there will be some distinctive odors associated with life aboard an icebreaker. We'll be onboard for about six weeks, and I am sure there will either be some funky human scents, or strong cleaning chemicals, or both. There will also surely be the smells of fuel and exhaust. But what will the Arctic Ocean itself smell like? What is the scent of sea ice? Do these smells change seasonally, or with the weather, or are they fairly constant? For Indigenous and coastal communities that have ventured for generations onto the sea ice and into the Arctic Ocean, what scents evoke that place?

As a child and young adult, the 'smell' of winter was more of a physical sensation than an odor. At particularly cold temperatures, nostrils freeze together briefly. Those that live in cold climes will be familiar with this experience. It isn't necessarily uncomfortable or problematic for short durations, and in fact is something that I remember fondly. It is a rare Homer winter now that temperatures drop to 'nose-hair freezing' level. I bet it will happen in the Arctic!

Many Arctic animals actually have specific adaptations to avoid this problem. Polar bears (Ursus maritimus) rely heavily on their sense of smell to find prey. They have a much longer nose (muzzle) than we do, and use intricate turbinate bones to further increase the surface area inside the nose. This likely helps them bolster their sense of smell, avoid moisture loss, and warm up the cold air entering their noses. See also Green, et al. 2012

Polar bears in the Arctic rely heavily on their sense of smell to find prey. Photo by Bill Schmoker (PolarTREC 2015), Courtesy of ARCUS.

Many accounts describe that polar bears can smell prey up to 1 mile (or more!) away and under up to 3 feet (or more) of snow and sea ice chunks. This information is primarily anecdotal and the distance is strongly dependent upon wind conditions. But suffice it to say, polar bears have an incredible sense of smell and their survival depends upon it. Recent research indicates that climate change-driven increases in winds in the Arctic might significantly hamper polar bear abilities to smell their prey. For polar bears, good habitat requires not just appropriate sea ice conditions but also windscapes conducive to successful smell-based hunting.

Though I can't smell as well as a polar bear, I am eager to sniff out the different odors of the Arctic Ocean and sea ice. I'll be sure to share with you what my nose uncovers. Packing scarves and balaclavas, I'll do my best to protect my sniffer from cold and wind. My nose isn't as adapted as a polar bear or wolverine to Arctic conditions and needs some extra help. However, that isn't to say all human noses are the same. Some research shows that people whose ancestors lived in the Arctic tend to have larger nasal turbinates than people whose ancestors lived in equatorial areas. How cool is that?

Don't forget to send your questions about the Arctic to me! I'll work with researcher aboard the Polarstern and Federov to find answers, insights, studies, and further related questions and share the answers here.

Education extension: The Nose Knows Fill 3-6 small, opaque containers (film cannisters work great if you can find them!) with objects that have a distinct smell. Natural items like soil, mint, yarrow, spruce needles, etc. are my favorite but you can use anything with a distinct smell. Poke holes in the top of the containers so that the smells waft out, or blindfold participants and allow them to open the containers and take a sniff. Pass one container around the circle. After everyone has sniffed, ask each person to share one descriptive word for what they smelled. With older youth or adults, ask them to describe what the smell reminds them of or specific memories. If you'd like, reveal what was inside the container. Repeat with the remaining 2-5 containers. For an extra challenge, have some containers that contain the same object/scent and ask the group to match them up by smell without peeking at the contents. For more fun activities related to the sense of smell, check out this resource from the University of Washington.