Geoscience Reference
In-Depth Information
Sleeping Bags
A good sleeping bag will keep you warm, even in severely cold temperatures. Down has long
been known for providing the greatest warmth with the least weight, but it is totally worthless
when wet. When used over long periods of time in subfreezing temperatures, down collects
frozen condensation from body moisture and gradually loses its insulating value. The new fiber
piles, such as Dupont Hollofill, are not as light or resilient as down, but remain warm when
wet. You can dunk a fiberfill sleeping bag in an ice-cold river, wring it out with your hands,
then climb right inside to get warm.
Caution:
Check the temperature ratings on the bag that you are buying and add a 10˚F to
20˚F safety margin unless you are a warm sleeper. The ratings are notoriously optimistic.
Mummy-style bags are more constricting, but allow you to cover your head and are much
more efficient insulators than traditional, inexpensive rectangular sleeping bags. Discount
stores carry fiberfill bags, but specialty backcountry stores will have the best selection.
Tip:
When I was a kid, we did not have money for expensive down sleeping bags, and it
was before the days of modern synthetic down-alternative fiberfill materials. In those days, we
camped with flimsy summer-weight Dacron sleeping bags that our parents had procured by re-
deeming “green stamps” from the grocery stores. In spite of the lack of proper backcountry
gear, we were quite happy snow camping on the sides of Mount Washington so we could chal-
lenge ourselves on the super steep ski slopes of Tuckerman's Ravine. We managed to snow
camp with our flimsy gear by bringing along an extra wool blanket and wrapping ourselves in
the blanket inside our lightweight sleeping bags. When the nights were extremely cold, we
would also go to sleep wearing our long underwear, insulated ski pants, sweaters, and some-
times even our ski jackets. We were kids, and we loved roughing it. We never knew what we
were missing until we got older, found part-time jobs, and were able to buy down bags and real
backcountry gear for ourselves. If we could “make-do” like this, so can you!
Insulated Sleeping Mats
A good insulating pad is important for both comfort and warmth. Without extra insulation un-
der your body, most of your body heat will be lost into the ground, especially if you are camp-
ing on snow. Stiff, closed-cell foam pads are lightweight and excellent for insulation, but are
not the best for comfort. Traditional air mattresses are cheap, but not as warm as closed-cell
foam and are often unreliable. A great modern invention, developed by Thermarest, is the
nylon-covered, self-inflating camping pad with an inner foam layer. The foam gives shape to
the air mattress and prevents internal convection air currents from robbing heat from your
