gloves vs. mittens

[gargamel]

Looking around for some useful informations on hypothermia I found a very interesting article about winter camping. I always felt, that wearing gloves doesn't keep my hands as warm as I would expect but I couldn't figure out the reason for that resp. thought this would be a subjective perception. But reading this dawned a light on me.

source : http://www.princeton.edu/~oa/winter/wintcamp.shtml

excerpt

Another general rule is that the efficiency of clothing is proportional to the diameter of the body part it covers. Thus a given thickness of insulation added to your trunk will be more thermally efficient than the same thickness added to your arm or leg. It will also help maintain that body core temperature. This is why vests work well to maintain body heat. There is an optimal thickness of insulation for each body part. Beyond that the added bulk tends to be more of a hindrance in movement than the added insulation is worth.

Have you ever noticed that your hands feel colder after putting on a thin pair of gloves? This is because when insulation is wrapped around a curved surface, the cross-sectional area of the insulation through which the heat may flow is greater as is the surface area from which the heat may be lost. This means that the total insulation efficiency of a given thickness progressively decreases as curvature sharpens over a surface. In addition, small cylinders, such as fingers, show a paradoxical effect. The addition of a thin layer of insulation actually increases heat loss until a thickness of about 1/4 inch is reached. This heat resistance gains as additional thickness is added. However, added thickness beyond 1/4 inch increases warmth very little in proportion to its thickness. This is one reason that thin gloves don't keep your hands particularly warm.

2. Hands - mittens are warmer that gloves because you don't contend with the curvature problem described above. Also the fingers tend to keep each other warm, rather than being isolated as in gloves. It is useful to have an inner mitten with an outer shell to give you layering capabilities. Also "idiot strings" are important to keep you from losing mittens in the snow. However, gloves are always essential as well in winter because of the need for dexterity in various operations.

[Just Jeff]

Seems to apply to the efficiency of wearing insulating pants to sleep rather than carrying a thicker bag, too. There was a pretty heated debate about this on TLB a while back.

[snowhoe]

I snowboard quit a bit and I am out in some pretty cold days, and by far mittens are so much warmer than gloves. Althogh I am only bringing a pair of fleece gloves for the A.T. in March. Go figure I guess I should take my own advice.

[Bassline]

I hike with thin gloves. They were perfect. I lost them at hardcore though, and never bought anymore.

[jackiebolen]

I hike with a thin pair of poylpro liner gloves. They are perfect because you can still hold your poles or whatever pretty well and also you can wear them while operating your stove/setting up your tent/hanging your food, etc. There was only one or two times (in the sleet) that I wished I had something waterproof or heavier.

Of course, winter camping is an entirely different story.

[DLFrost]

Another general rule is that the efficiency of clothing is proportional to the diameter of the body part it covers. {...} This is because when insulation is wrapped around a curved surface, the cross-sectional area of the insulation through which the heat may flow is greater as is the surface area from which the heat may be lost. {...} The addition of a thin layer of insulation {around fingers} actually increases heat loss until a thickness of about 1/4 inch is reached. {...} This is one reason that thin gloves don't keep your hands particularly warm.
A few comments...

(1) Gloves also protect the hands from convective heat loss, so any glove that blocks wind can make a big difference just by itself.

(2) Most materials used for insulation require a minimum applied thickness before they will properly retain heat--it's a function of the material. Surface area has little to do with it. Because the hands are gripping agents only certain materials can be used effectively, further complicating the issue.

(3) The biggest problem with most gloves is that they squeeze the fingers, restricting blood circulation. (This is especially likely when gripping--the insulation bunches up and presses into the finger joints where tissues are thinnest.)

Surface area vrs. volume is a legitimate factor, but not the only one.

Doug Frost

[Alligator]

During winter, I normally hike with a pair of 200 wt gloves. Usually, if the gloves get wet I can get them dry by evening, but I also carry shell mitts and 300 wt liners as back up. I'm not fond of wearing the mitts due to dexterity issues, thus the gloves. On my last trip out in January, wet snow and high winds prevented the gloves from drying out and had my fingers cold throughout the day, so I looked for an alternative. I picked up this pair of convertible mitts:
http://www.campmor.com/webapp/wcs/stores/servlet/ProductDisplay?productId=24731556&memberId=12500226

I haven't had them out yet, but they are made of the same windblocker material as my balaclava, so I expect good wind resistance. What I like most about them is the fact that all the fingers are convertible, even the thumbs. If you hike in the colder months, they might come in handy:jump .

[Mags]

FWIW: In all seasons, I use liner gloves (wool, army surplus) for the base.

In 3 season hiking, I have SilNylon mitts to put over them. Works well in all kinds of weather. (less than 3 oz total for this setup).

In winter, my layers conist of:

Overmitts (with a very light lining built in)
Fleece Convertible Mitts (same ones that Alligator just bought..you'll love 'em!)
Wool liner gloves

In both situations, can mix and match as needed. Most of the time, I find the liner gloves are fine by themselves, esp. when moving. I like the liner gloves for dexterity, the mittens for warmth when needed. Usually put the overmitts on when skiing downhill or buidling snow structures. Of course, I do most of my outdoor activities in Colorado which is a drier and sunnier climate even in winter. So YMMV.

[icemanat95]

I think the original quoted material is a touch overstated. A thin glove will almost always provide some protection from wind-induced heat loss (convection) even if the insulating power is negligible...so it is better than nothing.

Mittens are significantly warmer than gloves. I tend to ski with gloves unless it is bitterly cold, then it's mittens. I have several sets to choose from along with different insulation options. For mountaineering, I use mittens, though below treeline, I find I often need no more than liner gloves. For hunting and tracking, I have some camouflaged liner gloves with very tactile palms and convertible fleece mittens that alow me to fold over the mitten for warmth or fold the mitten end back to expose my fingers. Great combination.

[gargamel]

I think the original quoted material is a touch overstated.

Hey, it's from Priceton. What does me little dumb boy know? :D

The addition of a thin layer of insulation actually increases heat loss until a thickness of about 1/4 inch is reached.

I really don't know much about physics, but it matched with my (admittedly very subjective) observations.

As for the wind-induced heat loss: At my outfitters they have a wind generating machine to demonstrate the benefit of wearing windproof fleece gloves. It's amazing how big the difference really is.