Tuesday, January 09, 2007

Having Fun With Winter Camping (part II)

In Part 1 I wrote about how to keep yourself warm while engaged in outdoor winter activities. In this second installment I will discuss how to sleep out in the winter. I will also cover some important facts about avalanche danger.

OK, you know how to stay dry and warm in a winter wonderland. How do you deal with sleeping? I already mentioned that it is vitally important to go to bed dry. Always bring a fresh change of clothes to sleep in. Even if you will freeze your tail off while changing, make sure to change into dry clothes before finally bedding down.

Oh, and make sure you relieve yourself before bedding down. The cold seems to make the bladder more sensitive, so emptying it will help you have more uninterrupted time inside your warm sleeping bag. If you usually have to get up at night anyway, it’s a good idea to bring something you can use right in your shelter so that you don’t have to spend too much time freezing.

And speaking of sleeping bags, make sure you’ve got a good one. I have a nice mummy bag that is rated to 0°. If it’s going to be quite cold out, I will often bring a summer weight bag and will use it as a cocoon around my winter bag for extra insulation. Also, it’s good to keep your knit beanie handy. If you get cold, put it on.

Since you’re going to be sleeping on snow, ice, or frozen ground, you need plenty of insulation between you and that frozen surface. A good foam pad (dense foam pads are good) is a start. But even that is not enough. You need some kind of moisture barrier as well because the frozen stuff beneath you will melt during the night from contact with your warm body. So bring a tarp.

But you also need to realize that your body will put off quite a bit of moisture of its own, even in the cold. Most modern sleeping bags are constructed to allow the moisture to move away from your warm body and even out of the bag. But if the bag is right next to the tarp, the moisture can settle there and can still make you wet. So put your insulation between you and the tarp.

In addition to a foam pad, you need more insulation. If you are in an emergency situation, you can cut tree boughs. But don’t try that otherwise. Bring a couple of layers of cardboard or several thick newspapers. These things will conform to your body and have some insulation factor. I don’t advise sleeping on a cot. The cold air that passes between the underside of the cot and the frozen earth will not keep you warm.

Now for shelters. If you have properly prepared and there isn’t much of a breeze, you can make do without a shelter. Simply find a somewhat protected area (perhaps at the base of a large tree or in a natural hollow), lay out your bedding, put a tarp over the top, and go to bed.

But if you want to have some fun, try building an igloo, a snow cave, a snow mound, or a snow trench. All of these require work. One of the best resources that discusses these various shelters is the Field Manual of the U.S. Antarctic Program, Chapter 11. Some other good resources include:
http://www.ehow.com/how_4001_build-snow-shelter.html
http://www.bbc.co.uk/dna/h2g2/A810181
http://www.sastrugi.com/shelter.htm
http://wildwoodsurvival.com/survival/shelter/snow/index.html
http://alpharubicon.com/primitive/snowtrenchtrigger.html

My personal favorite is a snow trench with a tarp roof. I was once trapped in the cave-in of a snow shelter. Thankfully, I was rescued within the critical two-minute mortality timeframe by fellow campers. (Only 1 out of 3 victims survive a snow burial.) But as a result of that experience, I have some problems climbing into shelters with a snow roof. A snow trench is relatively quick to build, and with a tarp for a roof, I’m not in danger of a cave-in. However, I give up the insulation factor of having a snow roof overhead.

It is important to understand avalanche danger even if you are not going near a slope. My snow shelter cave-in occurred on a level surface, but was due to my lack of knowledge about snow conditions. When any layer of snow is loose and crystalline it means that it won’t pack well and the snow above it can easily slide. If you dig a trench, you can easily spot loose layers of snow. Without digging, you can tell from cracks across the surface, small snow slabs shearing off, or hollow or “whumping” sounds while walking across the snow. If any of these conditions exist, don’t try to build a natural snow cave. It’s OK to build a mound, but the roof of a natural cave under these conditions cannot be considered safe.

Avoid areas where avalanches and slides have occurred. Most avalanches occur on 30°-45° slopes, but they can occur on even a 10° slope. Slopes outside of managed recreation areas are rarely sufficiently controlled for avalanche danger for you to spend time on them. Slopes where there is little vegetation or that are shaped like chutes likely experience avalanches frequently.

You can learn more about avalanche safety at http://nsidc.org/snow/avalanche/ and http://www.avalanche.org/~uac/. Before going into the back country, check local snow conditions. You can find current Utah snow conditions at http://www.avalanche.org/~uac/.

Once again, you can have lots of fun camping and playing in the snow. All it takes is knowledge and preparation. Have a safe and fun time in the snow this winter.

4 comments:

That One Guy said...

As a kid from Canada, I once had the opportunity to do a winter campout in a snow cave, which we had to manufacture AFTER a hike, and BEFORE the short daylight hours were gone. It was a great time, there were about 6-7 people in it, and it was the most unique thing I had done in my sheltered (no pun intended) life up to that point.

We were actually warm. I note that in order to avoid a melting problem, one has to make sure the inside of the cave is the right shape, or you get drips on you all night long. We learned to telemark ski on that campout as well, as I recall.

Reach Upward said...

That sounds like a great adventure for a kid. You are correct about the shape of the shelter. I have often used candles in my snow shelters. They add a surprising amount of warmth. You just punch a hole in the wall that goes in farther than the edge of the tarp above. Then light a candle and stick it at the end of the hole.

The candle creates its own chimney as it burns. But it is also amazing how much light two to four candles make in a snow shelter when they have the snow walls (and perhaps ceiling) as reflecting surfaces. If you're sensitive to light while sleeping, the candles might not work for you.

That One Guy said...

this set of posts has brought up a couple of interesting reflections on my part, regarding the experiences I had as a young scout in another country, compared to the experiences my boys have had while growing up here. I'll post those observations over there, with a link back to these two posts.

That One Guy said...

and thanks for stirring those thoughts up to the surface, it's been a nice reflection on my youth...

:)