|
|||
|
Antarctica Picture
| Antarctica Cruise
|
Facts |
History |
Boots | Store
|
Clothes |
Whales
| Books |
Video |
Schools
| Forum |
Site Map |
FIDS / OAE's |
Top 10 fact File pages
Antarctica Fact File
Fascinating
Facts
Whales
Antarctica animals
Whale
species
Clothing
in Antarctica
Whales
and food webs
Antarctica
FAQ's
Emperor penguins
Antarctic
penguins
Antarctic
Science
and General
What's it like in Antarctica?
page 1
page 2
Antarctic
glossary
A - H
I -
Z
Threats to Antarctica
Fishing
and hunting
Mining,
oil and gas
Pollution
Sealing
and whaling
Tourism in
Antarctica
Cold and survival
Humans
Hypothermia
Cold acclimatization
Penguins
Animal Adaptations
Food
More on Food
Clothing
Clothing
2
Climate / Weather
Weather
phenomena
graphs:
Comparisons
Australian Coastal
Deep South
Climate Change:
Global
Warming
GW Antarctica
Misconceptions
Carbon sinks
Carbon cycle
Prevention
Offsetting
Tree Planting
Antarctic
slang
Antarctica Views
Antarctica blogs
Quiz
Antarctica
Lite
Antarctica
Fire History
 We all have ideas of what a comfortable
temperature is which may or not be an
agreeable fit with the ambient temperatures
that we live in. We all know people who on
the face of it aren't particularly different
to ourselves who are much more or less able
to tolerate cold or hot temperatures. It
would be very useful if we could influence how
we perceive the ambient temperature that we
find ourselves in.The ability to withstand cold is less to do with fundamental physiological differences in generating heat and maintaining body temperature than it is to do with how we perceive the temperatures to which we are exposed. Just because someone feels incredibly cold, it doesn't mean that they are actually any colder than someone else who is quite comfortable at the same temperature. Their body core and extremity temperatures will likely be very similar. The evidence for acclimatization in man is much less than in other animals as we take our microclimate with us usually in the form of clothing and housing or other shelter. The good news about this is that it is possible for most people to alter their perception of their temperature which is going to be easier than making any far reaching metabolic change. The bad news is that this process of acclimation can be quite uncomfortable and does need a kind of will-power that may be the weakest in people who really do like to feel nice and toasty at all times (though of course in other directions, they may well be capable of feats of perseverance that cold lovers cannot manage).
By exposing yourself to cold, there are many examples of how this happens, here are a few: Example 1:  A consistent, reversible increase in BMR
(Basal Metabolic Rate - the sum total of all
our metabolic processes when we are fully at
rest) by approximately 30% in winter occurs
in Korean women pearl divers (called amas)
who dive throughout the year. Such a
considerable enhancement of BMR in winter,
when the seawater is at its lowest (around
10°C), is primarily a result of cold
exposure.The Korean amas are subjected to daily, whole-body stress greater than any other group of human subjects studied (0°C air, 10°C water in winter). It should be emphasized that the amas dive throughout the year wearing only cotton bathing suits. They start diving at 12 years of age and continue until they are past 50. Because they are exposed repeatedly to severe cold over a long period, amas make a convincing example of acclimatization to cold, including the metabolic component of this process. From Life at the Extremes - USA 
|
UK
 Example 2:  "Birdie" (H.R.) Bowers who went with
Scott on his expedition to the South Pole in
1911 was remarkable for his extreme
hardiness, Scott described him as "The hardest
traveller that ever undertook a Polar journey as
well as one of the most undaunted." and
that he had "never seen anyone so unaffected
by cold". Bowers was able to sleep soundly
in conditions where a companion described
himself as being unable to sleep because of
the cold causing extreme shivering fits.Part of the reason for Bowers hardiness must be attributable to a regime whereby every morning once they had arrived in the Antarctic, he would strip naked outside and throw buckets of icy water and slush over himself - much to the horror and fascination of his companions. Example 3:  This is where this page began,
after being picked up by Search Engines I
started to receive emails which led to my expanding
on the subject here.I first arrived in Antarctica in early February 1985. I had left England in late winter when I suppose I was as cold adapted as happens on an annual basis in this country. Antarctica on my arrival was colder though it was midsummer there. I felt the cold and wrapped up against it, I then went through my first Antarctic winter. In early November the first ship of the season arrived and we winterers were all outside excited to see some new people, get mail and news of home, get fresh veg and cargo etc. While we were wearing t-shirts with our issued long overshirts with sleeves rolled up and untucked at the waist, we were rather surprised to see those coming off the boats in warm coats, fully done up and with hats and hoods on as well. Though we hadn't thrown buckets of icy water over each other or rubbed ourselves with slush and snow, ours was a diving base and all of the base members had dived on a regular basis throughout the winter. In addition to this we all had our own jobs that usually involved getting very cold at some point, in my case it was while fishing in boats or through ice. When I first arrived on base I hated getting fish out of nets as my hands and fingers hurt with the pain, flushing hot, then cold. I never actually enjoyed this part of the job, but after about a month was able to put up with it and just get on. The heat coming from the wrapped exhaust of our small launch was used to restore dexterity when our fingers wouldn't move on command properly, but it never really hurt again as it had done the first few weeks. * * * * * Similar anecdotal and scientific studies show that occasional repeated exposure to cold will result in increased cold tolerance. Such acclimation usually takes the form of daily cold baths or showers that really don't even have to be all that cold (water is very good at carrying heat away from the skin) 15-20°C / 60-68°F will do the job.You do need to be a particular type of person though to have the will power to do this as I said earlier. When I became cold acclimated in the Antarctic it was in the process of doing things that were either a whole load of fun or a part of my job that I couldn't avoid. being young and prepared to have a go at anything and everything probably helped too. A few years ago when our water heating broke down and I had to have a cold shower after spending the day in the garden it really wasn't a lot of fun. However... I really did feel great afterwards to the point where I thought "I'm going to do this all the time!" - I didn't. This seems like a good time for a serious health warning: There have been many instances of people jumping into cold water, having a heart attack and dying. The water doesn't need to be that cold and the person can be young and otherwise fit and healthy linky. Not everyone will react this way of course and you can minimize the hazard by entering the water slowly and in a controlled fashion. Here's a sensible approach and advice.
If your body shape results in a high surface area to volume ratio, i.e. you are relatively slender for your height with long slim limbs, then you will lose heat more quickly than someone who is of a generally stouter build. Birdie Bowers referred to above for instance was 5 feet 4 inches (163cm) tall and stoutly built which will have helped with his resistance to cold. Inuit and other polar and cold climate peoples are typically relatively short and stout while those who inhabit deserts and hot climates tend to be relatively slim and long limbed. Age has an influence too, as my wife occasionally reminds me that I'm not as young as I used to be in my Antarctic winter days and therefore feel the cold more than my sons. Elderly people may also be less likely to notice the effects of falling body temperature before it becomes a problem with slowed reaction times.
 You won't be able to keep warm if you're not
properly fed. Our bodies know this, in fact
they make this rule by making us hungry when
cold so there's more fuel coming in to be
burnt to keep us warm.By the same token, it is possible to lose weight by not wearing quite so many clothes in cold weather, yes you will feel cold and your body will make you hungry in order to eat, but if you can get through this and avoid eating more than normal, always being a bit cold is a good way to lose weight. Explorers who attempt feats of extreme endurance in polar and mountainous regions will often calculate the work they have to do (in KJ or calories), the food they need and balance this with the weight of carrying that food (and fuel to heat/cook it). They then often build into their planning that they will lose weight during their feat, though ensure that they are not so badly affected that their performance drops too much. Unlike early polar explorers, their modern day counterparts can rely on a fairly predictable quick return to the nutritionally enhanced modern world without too much trouble. One of the healthiest diets of all is the traditional high protein and high fat with little carbohydrate or plant food diet eaten by groups of people who are the Arctic living dwellers of various Inuit groups. This diet also supplies a daily intake of calories greater than that in more temperate climates. The key is that while high in fat, the fat is burnt off in keeping the body warm, it's the balance of food in and energy out that is important.
I don't feel that this page would be complete without mentioning the feats of Wim Hof, the Iceman who is able to withstand temperatures that would probably kill other people by mentally resetting his internal thermostat to affect his body temperature. BBC clip Further reading: Life at the Extremes - USA
|
UK
Human thermoregulatory responses to cold air are altered by repeated cold water immersion Acclimatization to Cold in Humans Role of core temperature as a stimulus for cold acclimation during repeated immersion in 20°C water Changes in thermal homeostasis in humans due to repeated cold water immersions |
School / Group visits to Antarctica
|
A common request I get
by email is from people asking me how they
can acclimatize themselves to cold
temperatures, so I've put together the
following page from my own experiences and
further research on the subject.
2001 