Temperature change in relation to altitu de

“I am trying to find a rule of thumb for the
expected decrease in temperature as one
ascends a mountain.

I know that I have seen a chart that is more simple to use than working through an
adiabatic lapse rate problem”

“3-5 degrees per 1000 feet climbed.

Keep in mind though, that the higher you go and the more exposed the mountain becomes, the windier it gets. I don't think that there is a rule of thumb for wind though. It just gets windier.
last edited: 2/21/06 10:34:04 AM”

“In the Catskills, I find significant changes about 2800 feet. I start out about 1000 feet. Here around 3500 feet you see tundra & stunted growth. The Catskills is mostly hardwoods, where the Adirondacks are conifers, (darker woods) but the Catskill peaks are mostly balsams. This cuts down on the views but evergreens do block the wind.

A lot of times in these 'ol mountains, you don't have to climb, just wait a while & the weather will change. Each little region tends to have it's own little micro climate also regardless of what it's doing elsewhere.”

“The Earth's atmosphere is divided into different levels or regions primarily by temperature. The lowest region of the atmosphere is the troposphere, which begins at the Earth's surface and extends to an altitude of approximately 10 miles (16 kilometers), or 55,000 feet—about 10.4 miles (16.8 kilometers), above sea level at the equator. Around the North and South Poles, the troposphere is only a little more than 5 miles (8 kilometers), or 28,000 feet (8,805 meters), deep. The temperature of the troposphere decreases about 2 degrees Celsius, or 3.5 degrees Fahrenheit per 1000 feet. Humans live in the troposphere and most weather occurs here.

http://www.centennialofflight.gov/essay/Theories_of_Flight/atmosphere/TH1.htm”

“Thanks for the post sticks. I had always been told it was 2 degrees for every 1,000 feet, but I never considered that it was 2 degrees Celsius:-)”

“That rule works just find when considering elevation change over a single point at the same time. You also need to take into account the aspect of the mountain and the time of day. That muddles up the equation quite a bit.”

“There are exceptions

like with temperature inversions or valley fog

and can be a drastic difference during freezing rain events with the lowland temperature sometimes in the teens and nearby mountaintops with temperatures in the 40's.
last edited: 2/21/06 6:27:06 PM”

“My rule of thumb (who made up that phrase?) is 3 degrees F for every 1,000'. This is most useful in determining how far I have to descend until the frozen urine in my pee bottle melts so I can pour it out.”

“Buck "my rule of thumb" This has been said to derive from the belief that English law allowed a man to beat his wife with a stick so long as it is was no thicker than his thumb. In 1782 Judge Sir Francis Buller is reported as having made this legal ruling. That same year James Gillray published a satirical cartoon attacking Buller and caricaturing him as 'Judge Thumb'”

“Hmmmm, I know I've climbed up to some snow covered peaks like Rainier and it's warm up there if it's sunny. Is it warmer than at sea level, maybe or maybe not. I'm not sure.”

“Thanks for the explanation, twofootdrive. As for beating my wife, I use the "rule of forearm" standard. But I've temporarly gone back to "rule of thumb" since she's 9 months pregnant at the moment.

Who are these sick people?”

“Average Lapse Rate is 3.5 degrees Fahrenheight decrease per 1000 feet elevation gained. This is based on starting at sea level with a temp of 59 degrees F and a pressure of 29.92 inches of mercury. This can fluctuate dependent on the moisture content of the air with the dry adiabatic lapse rate of up to 5.4 deg F per 1000 or moist lapse rate as little as 2 deg F. Of course this doesn't take into account temperature inversions through frontal inversions. Long-winded I know, but I teach this stuff. Short answer...3.5deg F per 1000 works like a charm in most circumstances in the mountains,...as a rule of thumb.”

“twofootdrive...One of my professors explained the "rule of thumb" the same way. Once I learned that, my use of the phrase decreased. Probably because I was afraid my wife would take the stick from me and start beating me! lol”

“That "rule of thumb" story is a myth, that keeps circulating despite evidence to the contrary. See, for example:

http://www.straightdope.com/columns/000512.html

http://www.phrases.org.uk/meanings/307000.html

http://research.umbc.edu/~korenman/wmst/ruleofthumb.html”