Source: Nature: "Life in Death Valley"
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Death Valley is the lowest, hottest, driest area in North America. In the summer, temperatures commonly run above 120° Fahrenheit. The hot dry air just sucks the moisture out of the human body. A person can lose over one gallon of water just sitting in the shade on a summer day in Death Valley. In this video segment from Nature, runners try to keep their cool as they race through Death Valley.
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The extreme climate of Death Valley is attributable to its location on the leeward (downwind) side of the Sierra Nevada Mountains in central California. Air that has been warmed and moistened by its passage over the Pacific Ocean is driven up over the Sierras as it is carried eastward by the prevailing southwesterly winds of the northern mid-latitudes.
As the air rises up over the mountains, it expands and cools, triggering condensation that forms clouds and causes precipitation on the windward (west facing) slopes. At the same time, the latent heat stored in the water vapor in the air is released by the condensation process, adding measurable heat to the air As the now warmer and drier air continues its eastward journey over the peaks and begins its descent into the valleys on the leeward side of the range, its temperature rises as it is compressed under the higher atmospheric pressure of the lower elevations. The fact that Death Valley lies below sea level causes even more compression of the descending air, creating a very hot and dry “rain shadow desert” in Death Valley.
At 3 p.m., the mercury peaks at one-hundred-twenty-eight. To run through the hottest part of the day seems impossible.
To take it slow just prolongs the agony.
Chris Bergland is hanging tough.
Chris: Last year I steamed through here and walked the end. So maybe this year I’ll walk this part and steam through the last half. So I’m optimistic.
But optimism alone won’t get even this three-time Iron Man champ through the race. Each runner must have a support crew working to cool them down with every step.
Crew member: “We started out with 25 gallons of water and about 500 pounds of ice. We still got some water – we haven’t used all our 25 gallons.”
“It’s like walking into a wall. It’s so hot I can’t even begin to describe it.”
The crews tangle with the heat themselves, but keep it all in perspective.
“It’s harder for them, right? So we can’t really complain, I guess.”
Pam Reed: “This is extreme, extreme. And you know it’s not something to fool around with. The pain is unbelievable.
Pam Reed has been down this road before. She’s a two-time winner of this race.
We humans cool ourselves by sweating, but here, perspiration vaporizes instantly. Pam does her best to rehydrate by drinking often, but the effect is only temporary.
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