I
frequently write and teach about the need to stay “comfortably cold” in the
winter, and for that matter in the spring and fall as well.
Now,
you might be asking yourself, “Comfortably cold, what’s that”? That is a good question, so let’s talk about
it.
The
first thing you need to know is that your body is like an engine, you take in
food as fuel and you burn it as you move about, work or even when you sit and
read an article from The Woodsman’s Journal Online! And just like an engine, only about 20% of
the food energy that you burn is used to do work, the other 80% or so becomes
heat. Like a car’s engine, you also have
a radiator, it is your skin! As with any
radiator, the greater its surface area in relation to its thickness, the
greater the heat loss and the more effective the radiator. Because of this your ears, nose and chin; and
your arms and legs, and in particular, your hands, fingers, feet and toes are
very good radiators: that is why during the winter they get cold and frostbit
the quickest.
Now
the more work your body does, the more food-fuel you burn and the more heat you
produce. Some of you have probably
poured water on an overheating radiator, to cool off a hot engine, this is what
your body is doing when you start to sweat: it is pouring water on the radiator
to cool off the engine!
But
the problem with sweating, is that you get wet.
And during the winter, but any time really, you must stay dry, because
water removes heat 32 times faster than air1. And the cold winter or Arctic air can quickly
pull heat away from your body.
Perspiration
in the Arctic or during the winter condenses and freezes as hoarfrost either in
your underlayers or on your windproof outer layer. Once this happens you become cold and
hypothermia begins to loom on the horizon!
“Okay,
so our bodies are a finely tuned machine, with a large radiator and getting
sweaty is bad”, you say, “but what is comfortably cold and how do you get
it”?
Comfortably
cold is when you are neither too warm nor too cold, you’re just right, maybe a little
bit cool, and you are not perspiring. You
can keep comfortably cold by reducing or increasing your activity level as you
become too hot or too cold. But the best
way to stay comfortably cold in the outdoors is by layering your clothes, and by
loosening, removing or adding layers as you warm up or cool down.
Layers of clothes wick
away sweat, adjust insulation and protect against wind, rain and snow. Layering allows you to make quick adjustments
based on changes in the weather and your level of activity by adding or
removing layers to trap heat or to avoid overheating. Remember it is always better to underdress
and be cool than to overdress, be too hot, perspire heavily, and become wet and
then cold later. Also, make sure that each level is sized larger than the one
under it so that the clothes fit loosely, because pressure from your clothes,
particularly around your joints, will quickly shut off the blood supply to the
pinched areas and make it more likely that you will become cold or frostbitten.
There are three layers
and each layer has its own function.
The base layer or under-most
layer is the most important as it is against your skin and keeps you dry. Your base layer should be made of wool,
synthetics or silk, since these fabrics transport perspiration away from your
skin. Also, these fabrics when wet dry
fast.
Your base layer or
underwear can be anything from briefs and a T-shirt in warm weather to long
underwear tops and bottoms in cold weather, and long underwear should be the two-piece
kind, not the one-piece kind, because they are easier to change if you get either
the tops or the bottoms wet. You
under-layer or base layer should fit loosely in warmer conditions to increase
air circulation and in cool conditions your base layer should be snug, but not
tight or constricting, to keep body warmth next to your skin.
The Middle layer, or
insulating layer, helps you retain heat by trapping warmed air close to your
body and it should be made of wool, fleece or goose down. The middle layer is available in three different
weights; lightweight for high energy activities or mild climates, mid-weight
for moderate activity or moderate climates and heavy-weight or expedition-weight
for low activity or cold climates. It is
always better to have two or more light-weight, middle layers than just one
heavy one.
The outer layer is
sometimes also called, the shell layer, the weather-proof layer or rain gear
and is vital in bad weather because wind and water can quickly chill you and
KILL YOU! Your outer layer should be a wind
and water-resistant or waterproof layer, to protect you from the rain, snow and
wind. Your outer layer must be roomy
enough to fit easily over your other layers and not restrict your movements or
make your clothes feel tight.
Excerpts from Naval Arctic Operations Manual: Part 1 General Information, pages 159, 161 and 165 to 166 |
If you are beginning to overheat, remove your hat or if you becoming too
cold put on a hat, since heat loss from your bare head can be up to
33% at 60oF (15oC), up to 50% at 40oF (4oC)
and up to 75% at 5oF (-15oC)2. Also, besides removing layers, if you are
becoming too warm you can open your zippers
and vents or loosen your clothes by loosening the waist belt of your outer-most
layer. If you are becoming cold you can close
your vents and zippers and tighten your waist belt. Don’t remove your outer most weather-proof
layer, instead remove your middle, insulating layers and then put your
weather-proof layer back on, Whenever
you stop to rest, put an insulating layer back on, under your weather-proof
layer, and whenever you begin to increase activity, remove one of your
insulating layers. Bring a pack to put the layers you have
removed into, because clothes tied around your waist or on the outside of your
pack will get snagged, lost or wet. The Naval
Arctic Operations Manual also has some great tips, which are below.
But
what do you do if you do end up with hoarfrost within your layers of clothes or
your clothes have become covered with snow?
You should brush the snow and hoarfrost off your clothes before you
enter some place warm. If you don’t have
a brush, you can use a smooth stick to beat the snow and hoarfrost out of your
clothes.
The author’s whisk broom for removing frost and snow, originally it was an umpire's brush, photo by the author. |
And
remember no matter what season it is, it is important that you stay dry! During the spring or fall, and even during
the summer, while wet clothes might not freeze, they can still overcool you and
cause hypothermia.
I
hope that you enjoy your next winter trip into the wilderness and I hope that you
can stay comfortably cold!
I
hope that you continue to enjoy The Woodsman’s Journal Online and look for me
on YouTube at Bandanaman Productions for other related videos, HERE.
Don’t forget to follow me on both The
Woodsman’s Journal Online and subscribe to BandanaMan Productions on YouTube,
and if you have questions, as always, feel free to leave a comment on either
site. I announce new articles on
Facebook at Eric Reynolds, on Instagram at bandanamanaproductions, and on VK at
Eric Reynolds, so watch for me.
That
is all for now, and as always until next time, Happy Trails!
Notes
1
Ministry of Forests, Wilderness Survival, [Ministry of Forests, British
Columbia, 1978], p. 46
2
Captain
Earland E. Hedblom, MC, USN; Polar Manual, Fourth Edition,
[National Naval Medical Center, Bethesda, MA, 1965], p. 37
Sources
Hedblom,
Captain Earland E. MC, USN; Polar Manual, Fourth Edition, [National
Naval Medical Center, Bethesda, MD, 1965], p. 37, https://ia800305.us.archive.org/33/items/PolarManual4thEd1965/Polar%20Manual%204th%20ed%20%281965%29.pdf,
accessed 12/07/2019
Ministry
of Forests, Wilderness Survival, [Ministry of Forests, British Columbia,
1978], p. 46
Moye, Jayme; “Day hikers are the most vulnerable in survival situations”,
[National Geographic, April 11, 2016], https://www.nationalgeographic.com/adventure/2019/04/hikers-survival-tips/,
accessed 12/06/2019
Navy, Department of the, Naval Arctic
Operations Manual: Part 1 General Information, [Department of the Navy, 1949,
Revised in 1950], p. 157-175,
https://ia600301.us.archive.org/27/items/navalarcticopera00unit/navalarcticopera00unit.pdf, accessed August 28, 2018
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