INTO THE WILD:

Staying Warm

While to the undiscerning eye most of the wilderness of Chicago either dies or departs before winter, surprising signs of life await the well-dressed and hardy. Here are some tips for rambling through Chicago Wilderness in comfort this winter.

Compiled by Gary Mechanic

Meadow vole.

Photo: Dan Kirk

Humans Have No Fur

What do whales, elephants, mole rats, walruses, and humans have in common? We’re among the few mammals, out of more than 4,000 species living today, that lack fur. Historically, humans have adapted to cold climates by appropriating the pelts of better-endowed mammals. Now engineered fibers and fabrics outperform the best furs.

Stop Thieves!

In cold weather, our heat is stolen by four thieves: radiation (through exposed skin), conduction (touching colder objects), convection (air or water moving warm molecules away from your skin), and evaporation (sweating and breathing). Click here for more on the heat thieves, and staying warm.

Accessorizing Keeps You Hot

Accessorizing is important in winter. Mittens will keep your fingers warmer than gloves. Thinner, layered socks are more comfortable than a single heavy sock. Don’t forget your galoshes or boots. And a hat that covers your ears and neck will eliminate the largest source of body heat loss regardless of how much, or how little, hair you have.

Other Heat-Saving Tips

Fuel up: Before you go out, eat plenty of food, including fat and protein, so you’ve got fuel to burn. Get moving: The more you walk, run, or do jumping jacks, the warmer you’ll be. Pee: Voiding your bladder will save the energy of warming that liquid. Get up: When you sit, heat leaves your body faster than if you stay off the ground.

Help Nature, Stay Warm

The best way to stay warm is volunteering at a habitat restoration workday. Sawing and tending a burning pile of buckthorn can make January feel like May. Cook County volunteers can check out fpdccvolunteers.org for workday schedules.

The Umbles

“The Umbles” is a device for staying aware of symptoms of hypothermia. First a person gets irritable and gets the grumbles. As his face cools, he gets the mumbles, followed by the fumbles as he loses fine motor control. Last, he loses gross motor control and gets the stumbles. Pay attention to your partners, and warm them in the early stages. Seek immediate medical help for serious cases. More about hypothermia.

The Power of Layering

Unlike our grandparents, who often just “bundled up” to stay warm, the modern outdoorsperson uses layering. Layering clothes creates a microclimate around your body and allows you to adjust your protection. Start with a base layer (a.k.a. underwear) that will transport moisture away from the skin and disperse it to evaporate. Synthetics (polypropylene and polyester) are best, since they are light, strong, absorb little water, and dry quickly (cotton is worst). A mid-layer provides insulation. Think flannel shirts, wool sweaters, and fleece vests. The outer layer protects from the elements and should allow air to circulate and excess moisture to escape. In damp, windy, and wet weather, a waterproof shell will work but will keep your sweat in as effectively as it keeps rain out. Gore-Tex and similar synthetic fabrics that “breathe” will keep you dry and comfy.

Animal Strategies

Puff Up, Shiver, Eat

Overwintering birds may grow a “winter coat” of feathers to help insulate them. Goldfinch feather weight is about 50 percent higher in winter than summer. Even with feathers fluffed, insulation alone will only keep their body about 20 degrees warmer than the air. So at colder temperatures, they shiver almost constantly to stay warm when at rest.

Huddle and Cuddle

The normally solitary white-footed mouse gets social and huddles with others in a den. By cuddling up, they reduce the area of exposed skin and radiation loss.

Be Sweet

Freezing solid would be fatal to most animals, but not the wood frog. When ice begins to form on a wood frog’s skin, the frog’s liver releases massive amounts of ordinary blood sugar, or glucose.
The syrup-packed frozen frog organs survive undamaged. When the frog thaws in spring, the amorous amphibian treks off to the breeding pond on a sugar high.

Take the Subway

The meadow vole creates an extensive network of tunnels through the snow from nest to food to seed caches. The loosely packed snow crystals trap air and insulate the tunnels from the colder temperatures above.