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by Liesl Clark and John Grunsfeld

Deadly Ascent homepage

Cold Toes

We've moved up to our camp at 11,000 feet, having strained under heavy packs and dragging sleds laden with the bare essentials that we'll require for the next two days. We arrived at 3:30 a.m. and still had an hour of work to do pitching tents onto the sloping site and battening our gear down in case of high winds or snow. Nothing can be left on its own: duffels, backpacks, sleds, ski poles, and ice axes must all be tied down by slings and carabiners to snow pickets buried deep in the slope. By morning, a storm was upon us, in typical Denali style, with whiteout conditions from blowing sheets of snow and spindrift. Half our team, led by Colby Coombs, hiked down to our cache of food and equipment buried at 9,700 feet, to drag it all back up on sleds. The other half stayed in camp to build snow block walls around our tents to buffer them from the high impact of wind and accumulating snow. (To see the route from Base Camp to the summit, go to Climb.)

Since we've arrived, high winds and poor visibility have prevented anyone from moving up to the Medical Camp at 14,200 feet. Howard Donner and Pete Athans made an attempt to move higher, but were blown back to camp at 11,000 feet. "The winds were upwards of 60 miles per hour and I was knocked off my feet. Our sleds literally became airborne," said Donner, his whiskered face frosting over in the bitter wind. We spend our time repairing snow walls and brushing snow from our tents while preparing mentally for the climb ahead.

For most of us, having both the world's authority on altitude and an astronaut in our midst has been a treat. Dr. Peter Hackett and John Grunsfeld attract audiences at each camp; they are celebrities of the highest sort for climbers curious about physiology and modern-day exploration. Although Grunsfeld (who has reached superhuman status among us landlubbers) has traveled higher than all of us, his physiologic response to the altitude and cold on Denali is all too human. The following is a report from Grunsfeld on the body temperature measurements he has conducted up to our current elevation at 11,000 feet on his quest for Denali's summit:

Grunsfeld Report

Camp-bound at 11,000 feet by strong winds and snow. Our activity consists primarily of building snow walls constructed out of blocks of snow cut from drifts on the side of the mountain. On the way from our camp at 7,900 feet to our perch here at 11,000 feet I was fully instrumented with both the core body temperature monitor and the skin temperature harness.

The core temperature is measured by the small pill that radios its temperature to a receiver I carry in my mountain bibs. The skin temperature harness has small wires with thermisters at their ends. These devices have a resistance that varies strongly with temperature. The data is recorded by a small electronic logger that I also have in my bibs. While the core measurements are automatically made every minute, the skin temperature is only sampled every 10 minutes and will be downloaded after we return from Denali. For the climb up to 11,000 feet and for the last two days I've had the sensors attached to my big toe, my foot, my left thumb, and on the side of my chest. Periodically I can check the temperature of my toe and my chest with a small meter.

We're very interested on this expedition in any correlation between skin temperature and body core temperature. So far my core temperature has remained relatively constant, around 99°F while in camp. While climbing it seems to rise to about 101°F, but drops quickly when we stop for a rest, with core temps so far as low as 95°F, which may be influenced by drinking cold water. During the night my core temperature drops to about 96°F in my warm sleeping bag.

My toe skin temperature has seen extremes of temperature and presents for me my biggest concern climbing Denali. For most of the climb from 7,900 feet to 11,000 feet my feet felt warm, but after our third rest stop at about 10,000 feet my feet began to get cold. This was likely due to a combination of mild hypoxia and cold as we ascended to higher altitude. Once we got to camp I measured the temperature of my big toe and found it to be 42°F! Yet in spite of the frigid temperature, I still had feeling in my toes. At the same time my chest temperature was a balmy 88°F. I hope I can keep my feet warmer as we climb higher on the mountain. This, it appears, will be my most serious challenge.

Moving in and out of our tents with the blowing snow is kind of like being on the space shuttle with its airlock. First we must enter the vestibule, opening and closing the fly—the outside protection of the tent. Once in the vestibule we brush all the snow off ourselves and only then can we open the inner door and enter the protection of the tent. Last night the sound of the wind blowing on the walls of the tent as I drifted off to sleep was somewhat disconcerting, but at the same time soothing as I drifted off to sleep. Today, while temporarily marooned here at the 11,000-foot Camp awaiting an uncertain break in the weather, I miss the warmth of my family.

Location: 11,000-foot Camp
Altitude: 11,000 feet
Air Temp: 20°F
Windspeed: 20 mph

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climber on the mountainside

The expedition did not arrive at 11,000-foot Camp until 3:30 am.

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On the Way (06.01.2000)
One Shot Pass (06.02.2000)
Midnight Rescue (06.04.2000)
Across a Glacier (06.05.2000)
Cold Toes (06.07.2000)
Cloud Walkers (06.09.2000)
Fourteen Medical (06.11.2000)
A Climber Saved (06.13.2000)
Lull Before a Storm (06.15.2000)
Frostbite (06.17.2000)
An Unforgiving Mountain (06.19.2000)
Stopped Short (06.20.2000)
A Great Loss (06.20.2000)
Bid for the Summit (06.23.2000)
Summit Reached (06.24.2000)


Set #1 (06.07.2000)
Set #2 (06.08.2000)
Set #3 (06.11.2000)
Set #4 (06.12.2000)
Set #5 (06.21.2000)

Meet the Team

Pete Athans
Colby Coombs
Dr. Howard Donner
John Grunsfeld
Dr. Peter Hackett
Caitlin Palmer

Liesl Clark directed "Deadly Ascent". Astronaut John Grunsfeld was a member of the climbing team.

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