> 6. Remember that 80% of the oxygen is in the first 3000 ft of altitude. > Mono is above that. Whoa! Alert!! You may want to recheck your source on that. Maybe that should be 30 Thousand feet. I'm from Denver, and not everyone there is DEAD!! I can attest that even at 14,000 feet, it is possible, though a tad painful, to bicycle uphill at at least 50% of the rate one can climb at sea level. Mike Wagenbach *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.paddlewise.net/ ***************************************************************************
You must have missed the mea culpa where I corrected my self and posted some facts. I am not going on memory any more but above 12,000 exercise gets pretty hard I think. Anyhow, see below: My response was way off base vs. the oxygen content at altitude. Thanks to an alert response from a reader of this list. Mono Lake is 6384.9 ft above sea level Oxygen situation is as follows I hope: Humans can survive for weeks without food; days without water; however, we can only survive for minutes without oxygen. While the percentage of oxygen in the atmosphere remains fairly constant up to 70,000 feet, the available amount of oxygen to sustain mental and physical alertness decreases above 10,000 feet. The atmosphere is primarily nitrogen (78%) with oxygen comprising 20.9 percent of the atmosphere. The atmosphere is generally considered to exist up to 100 miles (1,200 miles technically) and above this altitude the atmosphere is virtually a vacuum until reaching outer space. One-half of the atmosphere is contained from 18,000 feet to the earth's surface (the other 50 percent is above 18,000 feet). At sea level, the pressure of the atmosphere is 14.7 pounds per square inch (PSI). At 18,000 feet the pressure is 7.34 PSI. By 34,000 feet, the pressure is reduced to one-half of the 18,000 foot level to 3.62 PSI. It is this reduction in pressure (or in other words, the less dense air) that causes hypoxia. Hypoxia is the effects of an insufficient supply of oxygen to the body. Every person can have different symptoms when suffering from hypoxia (U.S. Air Force aircrews are required to take an altitude chamber ride every three years to reinforce and identify their hypoxic symptoms). Some of the common symptoms are: lightheaded sensation, dizziness, reduced vision, and euphoria. The early signs of hypoxia generally begin at 10,000 feet. U.S. Air Force aircrews must use supplemental oxygen when the cabin pressure of the aircraft reaches this altitude. (NOTE: The cabin altitude of an airliner and other transport aircraft by design will climb no higher than 8,000 feet.) Without supplemental oxygen, your blood has about 90% of its normal oxygen level at 10,000 feet. -- =^..^= --Mel-- Mel Lammers mslammers_at_earthlink.net ----- Original Message ----- From: M. Wagenbach <wagen_at_u.washington.edu> To: <PaddleWise_at_lists.intelenet.net> Sent: Thursday, September 02, 1999 1:51 PM Subject: Re: [Paddlewise] Mono Lake > > 6. Remember that 80% of the oxygen is in the first 3000 ft of altitude. > > Mono is above that. > > Whoa! Alert!! You may want to recheck your source on that. Maybe that should > be 30 Thousand feet. > > I'm from Denver, and not everyone there is DEAD!! I can attest that even at > 14,000 feet, it is possible, though a tad painful, to bicycle uphill at at > least 50% of the rate one can climb at sea level. > > Mike Wagenbach > *************************************************************************** > PaddleWise Paddling Mailing List > Submissions: paddlewise_at_lists.intelenet.net > Subscriptions: paddlewise-request_at_lists.intelenet.net > Website: http://www.paddlewise.net/ > *************************************************************************** > *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.paddlewise.net/ ***************************************************************************
On Thu, 2 Sep 1999, Mel Lammers wrote: > You must have missed the mea culpa where I corrected my self and posted some > facts. I am not going on memory any more but above 12,000 exercise gets > pretty hard I think. > Sorry, took a 3 day weekend for coastal and surf paddling, and didn't do a good job of tracking all the threads. Around 12,000 feet I often get a tiny snippet of some awful, long-forgotten pop song stuck in my head repeating over and over and over. Maddening, and presumably a sign of a threshold in mental functioning. In civil aviation, you're allowed to fly 30 minutes without O2 between 10K and 12.5K feet. Mike *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.paddlewise.net/ ***************************************************************************
At 15:25 9/2/99 -0700, "M. Wagenbach" <wagen_at_u.washington.edu> wrote: >On Thu, 2 Sep 1999, Mel Lammers wrote: >> I am not going on memory any more but above 12,000 exercise gets >> pretty hard I think. >> >Around 12,000 feet I often get a tiny snippet of some awful, >long-forgotten pop song stuck in my head repeating over and over and over. >Maddening, and presumably a sign of a threshold in mental functioning. > >In civil aviation, you're allowed to fly 30 minutes without O2 between >10K and 12.5K feet. > >Mike barely enough time to get over many of our passes ;-) medical studies have also said at about 10K ft, people develope additional capilarries [sp] in their lungs. i know some anthropologists that work in peru frequently, so they chose to live above 10.5K here in colo... brrrrr mark #------canoeist[at]netbox[dot]com-------------------------------------- mark zen o, o__ o_/| o_. po box 474 </ [\/ [\_| [\_\ ft. lupton, co 80621-0474 (`-/-------/----') (`----|-------\-') #~~~~~~~~~~~~~~~~~~~~~~~~~~~_at_~~~~~~~_at_~~~~~~~~~~~~~~~~~~~_at_~~~~~~~~_at_~~~~~ http://www.diac.com/~zen/paddler [index of Paddling websites I manage] Rocky Mtn Sea Kayak Club, Colorado River Flows, Poudre Paddlers The Colorado Paddlers' Resource, Rocky Mtn Canoe Club Trip Page -- Computers are useless. They can only give you answers. --Pablo Picasso *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.paddlewise.net/ ***************************************************************************
"Around 12,000 feet I often get a tiny snippet of some awful, long-forgotten pop song stuck in my head repeating over and over and over. Maddening, and presumably a sign of a threshold in mental functioning." This is usually what my friends and I would refer to as a symptom of "krumhutlz(spelling?) madness", after the little trees you encounter at the edge of treeline, which is usually where we are when our thinking starts to go a little haywire... -A *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.paddlewise.net/ ***************************************************************************
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