aclyon wrote: ↑Sun Jan 07, 2024 12:00 pm
ok, i'll bite. this californian wants to know how you do it. what kind of gear and camping techniques do you use to stay warm in -40C?? i can't even imagine being outside in that kind of cold. i certainly can't imagine having my face exposed, i'd need a head sock or somesuch. and wow, a 40 person group going pretty slowly-- this sounds like a recipe for freezing to death!
Clothing wise, need to have layers in order. Prefer anything quick drying with high warmth-to-weight ratio. Think we used 3-4 layers each, and some, especially women used insulated skirts or shorts as well. A group moves slow, making it colder for those that would naturally ski faster.
Ski boots have to be well-insulated. Heat comes from movement and getting your heart rate up. We use VBL socks to block sweat from wetting/freezing our boots.
We did tape our faces or use masks some of the time when it was windy.
For taking breaks, one would want thick down jackets and skirts/pants. We had the luxury of food thermos jars with a ready-made warm lunch inside. Morale boost like nothing else. Also liquids in thermoses for coffee, juice etc. Need to stay well-hydrated and consume enough calories for the body to help in keeping warm. I keep my water bottles warm under my clothing. It is slow to drink hot liquids, lukewarm is best. Need to use electrolytes as most water comes from melted snow.
We had sleeping bags or sleeping bag combos which work down to about -40°. The down will collapse a bit each day, frost buildup is strong in such low temperatures, meaning insulation is lost each day. Most used double bags, thick synthetic on top and down inside. Hoping the dew point remains mostly inside the synthetic bag. I personally use a -35 down bag and sleep in two layers. I think I lose about a degree per day centigrade. When it collapses enough, I add my down jacket as an extra duvet. Double sleeping pads, cell foam on top, ensures staying warm from underneath. R-value 7 or higher is required. The ccf pad, even a very thin one, will feel warmer than just higher R-value air mattress. The cell pad heats quick when you toss and turn to a cold spot on the mattress.
When it gets really cold, or the bags do not insulate enough anymore, one can build snow shelters to boost warmth. Easiest to dig a hole in which your setup fits, lay skis and poles on top and use a tarp/tent cloth to make a roof, insulated with snow. You get 10-20 degrees warmer sleep this way and it takes 30 min to make a shelter.
Typically we just use winter tents, usually tunnels, strong domes or pyramids with solid innernets. These give you a few degrees warmer sleep. More people, more warmth. Locate under a tree and be protected from radiation heat loss.
You need to be careful not to accumulate too much frost everywhere, scrub it off where you can
