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Thin Atmosphere

Enoki, you're absolutely right. Here's an article from the National Library of Medicine (open access) which defines altitude sickness, and discusses the effectiveness of some pharmaceuticals intended to prevent symptoms of AS. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2907615/

In a Traveller themed short story I wrote, which I'm hoping to have published in an e-zine later this year, the protagonists find themselves on a planet with a thin atmo and are unexpectedly thrown into danger and have to run, without breathing gear. I've incorporated some symptoms of AS to make their situation more complex, but they've had some anti-AS meds so they're not totally incapacitated. If I was really strict about the effects of AS on them, they wouldn't be able to function and it wouldn't be much of a story. So my advice is make the density of the atmosphere an element of danger, but don't drag the adventure down with too much science. It's hard to be heroic when you're groggy and exhausted from walking to the front door.

Cheers,
Bob W

Actually, the manual recommends about 2 weeks for acclimatization, and also points out that going from high altitude to a sea-level altitude is also a problem. The Bolivians ran into that in the Gran Chaco War with Paraguay in the mind-1930s, as their men were used to altitudes of about 10,000 to 14,000 feet, but were fighting at near sea-level in tropical conditions.

b. There is a need, however, for a conditioning and acclimatization period of 10 to 14 days for troops to be trained in altitudes of 8,000 feet or more. After a week or two at high altitude, the average soldier will find that he is less exhausted, his headache is gone, he sleeps better and his appetite is normal, and as days pass he will find that life in the mountains is definitely exhilarating.

The same time factor for acclimatization holds true for troops in extreme cold or snow conditions.

Tossing this to the moderators, Aramis and Cryton, would you like to have the manuals available for download from the site? If so, I will figure out how to upload them. They are all in PDF format.
 
Some notes on cold weather operations. The first is from Combat Support in Korea and the second is from the Department of Army pamphlet, Warfare in the Far North, part of a series of pamphlets written by German officers for the US Army of their combat experiences in World War 2, primarily focused on the Eastern Front.

In Korea there were some increases in our loads that were very necessary and justifiable, such as tents and stoves. The extreme cold of northern Korea made it absolutely essential to have shelter throughout the division. It was necessary that each infantry platoon have a squad tent and stove so it could rotate its men and allow them to get warm. But enough tents for a division certainly complicated our transportation situation.

Report of Lt. Col. Charles R. Scherer, Assistant G4, 7th Infantry Division

The Finn, who learns to use an axe and a saw from childhood on, was able to make use of the means available in the woods and to spend the night in the open even in the most severe cold. The clothing of the Finnish soldier (fur cap with ear and neck protector, warm underwear, woolen scarf, fur gloves, warm footgear (In wintertime the Finnish soldier wears boots of a larger size than in summertime so that he can wear two pairs of woolen socks.) offered good protection against the cold. The Finnish tents, which were made of plywood and could be heated, proved to be very satisfactory. They could be put up quickly and moved easily. In wintertime these tents were set up for even a rest of but a few hours. When tents could not be set up, the Finnish troops built log fires and windbreaks in the open very rapidly. Whenever a pause of several days occurred during an advance, barrack-like huts were constructed with amazing speed. These offered protection against the cold and, in case the troops stayed in the same place for some time, were improved until they were quite comfortable. Thanks to the background and appropriate training of the troops, frostbite was practically unknown among the Finnish soldiers. In December 1941, when news reached Finland about the heavy losses the German Army was suffering in Russia because of the severe winter, Marshal Mannerheim made the following remarks on the subject: "Losses among the troops because of frost weigh heavier on the commander's conscience than battle casualties. Because in this case there always remains the disturbing feeling that losses due to the cold might possibly have been avoided if greater precautions had been taken."
 
Again, this comes from Combat Support in Korea.

47. Temperature Adjustment

Michael Slauta, Special Observer for The Quartermaster General. (From a speech, 16 November 1950.)

The reaction of troops from tropical countries to wet-cold climate is unfavorable. When the Filipinos arrived in Korea on a September night, the temperature was a very comfortable 65 degrees. But the Filipinos felt cold. They were actually “freezing” and, before they moved away from the train, they had broken into their packs and had blankets draped over their shoulders. Before two days passed we had to issue them winter clothing.

I saw the same thing in the Solomon Islands one evening when the rains brought a blast of cooler air down to sea level. It was about 65 degrees again, but the Islanders were grabbing every bit of clothing that they had to put on. When one of the fisherman that I talked with on the dock every night asked me if Chicago was colder than what they were experiencing, and I said that it was colder at times, he very solemnly informed me that "Chicago is a very cold place." I did not have the heart to tell him about Alaska. I am not sure he would have believed it if I had.
 
Russian World War 2 Cold Weather Gear

The following information comes from a Military Intelligence Service publication in World War 2 called Tactical and Technical Trends, which has an immense amount of valuable data in it. This excerpt covers Russian cold weather wear and behavior. Having been in extreme cold, I can appreciate the emphasis on cold weather shelter.

As the Germans withdrew, they often burned the villages behind them, leaving the ground thawed around each house.. The Russians at once dug this ground down to about 5 or 6 feet. It was then roofed over with logs, tarpaulin, or brushwood, and floored with brushwood, or with straw if available. A stove, with a pipe chimney, was installed in the dugout. These stoves were usually improvised from old oil drums.

Where there were no villages, the Russians would dig the snow in the_ forest down to ground level, and build up a thick snow wall around an area of 8 feet by 12 or 15 feet. Evergreen fir branches would be used to line the floor and walls, and the compartment would be roofed with more branches, as well as a tarpaulin, if available. Finally the inevitable stove and chimney were added.

For these winter operations, the Russian soldiers were provided with good thick underclothing, of which they frequently wore two sets. Over this was a thick shirt and pullover. Over the pullover went padded trousers and coat, and then an overcoat or the short sheepskin shuba. Headgear consisted of a fur cap, a winter cap, and, frequently, a scarf belonging to the individual soldier. The Russian soldiers wore two pairs of gloves: an inner pair with the first two fingers and thumbs free; and an outer pair of mittens, worn when the use of the trigger finger was not required. No blankets are carried in a Russian division.

On his feet the individual soldier wore the varlenki or felt boot. Socks were not worn under the varlenki. but a piece of cloth, 2 feet by 1 foot 6 inches, was wrapped about the feet and ankles. In deep snow, trousers were worn outside the varlenki and tied round the bottom to prevent snow getting inside the boot.

Russian opinion is that the vajripmlri is the most satisfactory footwear for snow, and that it has enough wear in it to last through a complete winter. Although it is a felt boot, the wear is less pronounced than might be expected, since the troops can always march on the soft snow by the road. The varlenki has the advantage of drying very quickly in front of a stove, although this is not usually necessary, for in Russia one normally meets a dry type of snow.

Certain specialist ski troops wear a special ski boot, but the ordinary
infantry ski in their varlenki.

Notice the layering in the Russian wear, and also the emphasis on footwear.
 
As this was originally about Thin Atmosphere, I forgot that animals might have troubles too. The following is from Hiram Bingham's Inca Land: Explorations in the Highlands of Peru. Bingham was the European (counting residents of the US) discoverer of Machu Picchu of the Incas.

Between us and the first snow-covered slopes, however, lay more than twenty miles of volcanic desert intersected by deep canyons, steep quebradas, and very rough aa lava. Directed by our “guide,” we left the Cotahuasi road and struck across country, dodging the lava flows and slowly ascending the gentle slope of the plateau. As it became steeper our mules showed signs of suffering. While waiting for them to get their wind we went ahead on foot, climbed a short rise, and to our surprise and chagrin found ourselves on the rim of a steep-walled canyon, 1500 feet deep, which cut right across in front of the mountain and lay between us and its higher slopes. After the mules had rested, the guide now decided to turn to the left instead of going straight toward the mountain. A dispute ensued as to how much he knew, even about the foot of Coropuna. He denied that there were any huts whatever in the canyon. “Abandonado; despoblado; desierto.” “A waste; a solitude; a wilderness.” So he described it. Had he been there? “No, Señor.” Luckily we had been able to make out from the rim of the canyon two or three huts near a little stream. As there was no question that we ought to get to the snow line as soon as possible, we decided to dispense with the services of so well-informed a “guide,” and make such way as we could alone. The altitude of the rim of the canyon was 16,000 feet; the mules showed signs of acute distress from mountain sickness. The arrieros began to complain loudly, but did what they could to relieve the mules by punching holes in their ears; the theory being that bloodletting is a good thing for soroche. As soon as the timid arrieros reached a point where they could see down into the canyon, they spotted some patches of green pasture, cheered up a bit, and even smiled over the dismal ignorance of the “guide.” Soon we found a trail which led to the huts.

Also a comment on what may or may not grow at an altitude of 14,000 feet.

We found that the Indians kept a few llamas. They also made crude pottery, firing it with straw and llama dung. They lived almost entirely on gruel made from chuño, frozen bitter potatoes. Little else than potatoes will grow at 14,000 feet above the sea.
 
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I came across this in Roy Chapman Andrews book, Camps and Trails in China, covering his 1916 expedition to China for the American Natural History Museum in New York. Andrews is view by some to be the basis for Indiana Jones. I have posted it elsewhere, but thought that it might be of interest to the community at large.

He was in a mountainous area, at between 8,000 and 12,000 feet in altitude, which I would think probably put him in what Traveller would regard as a "thin" atmosphere. He and his party, used to much lower, near sea-level elevations had much more trouble than the natives of the area. It might be something that you would want to consider in running an adventure or campaign.



Emphasis is added.

In line with the thought on atmosphere, I was wondering how it would work to include "cold" as one of the atmospheric taints, as cold, dry air is extremely hard on the lungs. Having been in Alaska and out at 62 below zero Fahrenheit, which is minus 52 Celsius, I can attest to how it feels. You have to have either a mask or scarf or muffler of some kind over your mouth, or it feels like you are breathing fire.

Edit Note: Just came across this in the Andrew's book, and it nicely illustrates my ideas. Note the 15,000 foot altitude.
I saw a small film about Andrews some thirty years ago, and then another blurb about him in a National Geographic overview of their Centennial. Great stuff. I wish there was a DVD of both films. If you come across them, then check them out. Great stuff about science and exploration, before NG started dabbling into low brow TV.
 
Do not forget a pressurized coffee pot, either.
Are you thinking a sealed vessel percolator, or a high pressure source (like an espresso machine)?

An espresso machine, or even most pumped (rather than thermal-expansion feed) systems should be able to work just fine. Likewise, a pressure feed system using compressed air to push heated water would have the side benefit of increasing the boiling point to the ideal-for-brewing-coffee 91-96°C range.

It's only when the boiling point drops below 90°C that extraction changes the flavor significantly. At 85°C, the extraction is much less sharp. At 15°C, it takes days, but produces a VERY mellow and tasty coffee...

Oh, and the 90° boiling point is about 0.75 Bar... so a thin or very thin ain't going to brew good coffee by the cowboy method (toss loose grounds into a pot and boil - I'll note that I've never had success using the pressure cooker for that purpose, and I've tried).
 
I am thinking of a sealed vessel percolator or drip with pressurized hot water feed. Not a fan of expresso.

Also, I have been thinking about the reaction of someone from a dense atmosphere in a thin atmosphere environment. Would that be the equivalent of s "very thin" atmosphere to someone used to a standard atmosphere environment?
 
Also, I have been thinking about the reaction of someone from a dense atmosphere in a thin atmosphere environment. Would that be the equivalent of s "very thin" atmosphere to someone used to a standard atmosphere environment?

Probably should be - I know that the other direction is true - 10,000 ft MSL dwellers need some adaptation time (That's a thin atm altitude); nowhere on earth approaches a dry 1.25 bar, but I've read that even the 1070bar peak average (dead sea's shore) does result in some adaptation issues when traveling upwards.

It's worth noting that the Colorado Avalanche hockey team has been claimed by players in almost all other NHL Teams to be possessed of a major home ice advantage due to the altitude change; no other teams have the same altitude (around 1.4km); most are pretty close to MSL (a few hundred meters, peak; some below 100m MSL). A few Colorado players have complained about the thickness of the air when playing in Florida or Washington. And that's just a mile up.

It's also worth noting that people adapt to life in the Andean villages within a year, but aboriginal peoples always retain an advantage at altitude. Habitation at up to 2.5km...
 
I know that during the Chaco War between Bolivia and Paraguay in the 1930s that the Bolivian troops from high and dry altitude had major problems when in the maybe 500 foot above mean sea level and also quite humid air of the Chaco area. Similar comments show up in some of Percy Fawcett's notes.

I keep thinking of having as a unique atmospheric taint on a dense atmosphere world be oxygen.
 
I know that during the Chaco War between Bolivia and Paraguay in the 1930s that the Bolivian troops from high and dry altitude had major problems when in the maybe 500 foot above mean sea level and also quite humid air of the Chaco area. Similar comments show up in some of Percy Fawcett's notes.

I keep thinking of having as a unique atmospheric taint on a dense atmosphere world be oxygen.

When I was 9 I moved from an altitude of ~8,000 feet (dry) to Sea Level, much higher humidity. All of us kids of course did sports. There was ZERO problem. In fact, for about a year I dominated in the 440 + runs. By then I had acclimated and got winded like everyone else.
 
When I was 9 I moved from an altitude of ~8,000 feet (dry) to Sea Level, much higher humidity. All of us kids of course did sports. There was ZERO problem. In fact, for about a year I dominated in the 440 + runs. By then I had acclimated and got winded like everyone else.

Always an exception to the rule. I am reporting what other people have observed on a regular basis. The same holds true from moving personnel accustomed to warm, humid climates to cold, dry ones, and vice versa.
 
No. 7 exceptions in one family of 7? 'fraid not. I've known MANY people making similar moves. No problems. There is no documented, validated medical studies that shows a problem either.

I was looking at people going from 14,000 feet to near sea level. And also looking at the reports of military units that have done so.
 
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