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10b4me
Boulder climber
member since 2002
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Nov 30, 2012 - 11:53am PT
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Cragman, that picture of Carson Peak is very impressive
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HighTraverse
Trad climber
Bay Area
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Nov 30, 2012 - 11:58am PT
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^^^^
just down the road (12 miles as the hawk flies) from my place and 1000 feet lower
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ydpl8s
Trad climber
Santa Monica, California
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Nov 30, 2012 - 12:02pm PT
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It bears repeating that the density of air changes with altitude. Also (and this is kind of counter-intuitive) moisture Decreases density. So...40mph at sea level feels harder than a 40mph wind at 15,000 feet. Like the difference between getting hit by 20 mph bike vs a 20 mph car.
You can see from the graph below that as you increase height, density goes down, partial pressure of water vapor (vapor pressure) and temperature play a part also.
EDIT: Well I didn't do too good of a job getting the formulas over here, so here is a good reference for all of you that want to look deeper into the subject.
http://wahiduddin.net/calc/density_altitude.htm
EDIT2: This is also directly tied into why water boils at lower temperatures at higher altitudes. Think back to your 8th grade physical science class when they put a beaker of water under a vacuum bell and got it to "boil" at room temperature as they decreased the pressure.
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HuecoRat
Trad climber
NJ
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Nov 30, 2012 - 12:11pm PT
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Keep Hurricane Sandy in mind. The top winds were 70 mph and the destruction was enormous. I will try to post some photos of what the wind did near my house. Literally hundreds of trees uprooted or snapped off.
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HighTraverse
Trad climber
Bay Area
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Nov 30, 2012 - 12:13pm PT
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Nice graph
So what is the mass density of air where I live at 800 meters when saturated with H2O?
Compared to dry air at sea level.
Or considered another way, when I was knocked off my feet on the summit of Rainier on a dry day, the wind speed would have been about 50% higher than required to knock me off my feet at sea level.
Or since I'm familiar with 30 kts of wind when sailing on the SF Bay, I'll be underestimating the wind speed when I'm at altitude?
Of course, without instrumentation, it's all a Wild Arsed Guess.
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TradEddie
Trad climber
Philadelphia, PA
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Nov 30, 2012 - 12:34pm PT
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I've only climbed at JT once, and it was incredibly windy, I had a fist jam deep in a crack when a gust blew me sideways and I thought my arm was going to break. Twentynine Palms weather station recorded gusts at 70mph that day. call it BS all you like, you'll know when its 70mph.
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Reilly
Mountain climber
The Other Monrovia- CA
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Nov 30, 2012 - 12:38pm PT
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Although Donini claims to be the Windmaster amongst us I've heard from
reliable sources that Guido can break a gale with his bare hands.
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nutjob
Gym climber
Berkeley, CA
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Nov 30, 2012 - 01:10pm PT
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toss a ciggy butt out... Lame!
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survival
Big Wall climber
Terrapin Station
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Nov 30, 2012 - 01:15pm PT
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I don't know about all that sh#t but it was blowing like 90 here a minute ago.....
( . )( . )
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donini
Trad climber
Ouray, Colorado
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Nov 30, 2012 - 01:16pm PT
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I'm just the land guy. Guido gets the 71% covered by ocean.
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Reilly
Mountain climber
The Other Monrovia- CA
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Nov 30, 2012 - 02:58pm PT
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And then there is spending a night in a tent at 10,000' when an official
weather station nearby, but 3000' lower, recorded winds of 105 mph. Two
ice axes, two ice tools, flukes, deadmen (lol), and X ice screws did
the job. Thank you JanSport! The proto tent survived with only two of the
three poles breaking. (but didn't tear the sleeves!)
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Caveman
climber
Cumberland Plateau
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Nov 30, 2012 - 09:00pm PT
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I got to experience winds in the neighborhood of 50mph recently. The wind speed was not that big of deal. The problem was that about 500ft to the west the wind was blowing to the south at 50mph. 500 ft. to the east the wind was blowing north at 50mph. Directly overhead at about 1500ft was an inverted hersheys kiss shaped cloud reaching for the ground. The most dangerous winds were wrapped in clouds and sounded like they had a freight train in them. Highest gusts in the storms exceeded well over 100mph. We didn't have trees down. We had forests disappear.
One thing I learned that day..........if you are a tornado chaser, you most likely do not want to catch one!
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GDavis
Social climber
SOL CAL
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Topic Author's Reply - Nov 30, 2012 - 10:15pm PT
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Seems like a lot, but most of these posts are unnecessarily....
..... long winded.
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couchmaster
climber
pdx
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Nov 30, 2012 - 10:48pm PT
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"I guess you'd probably hate this site:
http://windmapper.com/?Loc=CA
Warning: contains people quoting wind speeds."
GREAT site QINTNL! I was down today working on a roof that blew off in 100 mph gusts a week back. Site says it was 31 mph today, which was within 1 mph of what I guessed it was. Very sweet! Says that it's gonna be getting up to 59 mph in a few days, looks like I need a few blue tarps once the rest of the shingles blow off.
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