Ask A Scientist Weather Archive

name         Andrea Michelle W.
status       student
age          14

Question -   I was wondering if I would be able to you any input from
you on how elevation above sea level would affect the air temperature of
the surrounding areas.  In previous research, I have found that air
temperature drops an average of 6.5 degrees Celsius per every 1000 feet,
and I was wondering if you agree with that.  Thank you for your time and
consideration.
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Dear Andrea-

   You are correct in your calculation of temperature decrease with altitude.
   This is the "lapse rate for a standard atmosphere," but, in actuality, the
lapse rate will vary from day to day, and even throughout the day.

For a table showing the lapse rate for a standard atmosphere, see this
link...

   http://www.usatoday.com/weather/wstdatmo.htm

Wendell Bechtold, meteorologist
Forecaster, National Weather Service
Weather Forecast Office, St. Louis, MO
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Andrea,

Actually, the temperature drop with height (called lapse rate
by meteorologists) is 6.5 degrees Celsius per 1000 meters (not feet)
or, in English units, it is 3.57 degrees Fahrenheit per 1000 feet.


David R. Cook
Atmospheric Research Section
Environmental Research Division
Argonne National Laboratory
=============================================================
The physical properties of the atmosphere changes minute by minute, so
there is not a single answer to your question -- but do not despair -- there
is a massive compilation of data averaged over certain solar conditions,
elevation etc. called:
"The U.S. Standard Atmosphere (1976)" published by the National Oceanic and
Atmospheric Administration, NASA, and other governmental departments. This
is used as a reference for aeronautical engineers, physicists, etc. to do
calculations on a common basis. You can find condensed versions in
handbooks, specifically
"The CRC Handbook of Chemistry and Physics". The Handbook of Chemistry and 
Physics is the ultimate book for this type of 
information.  http://www.hbcpnetbase.com/CRCBook/
Your library will probably have a copy. You can also find specific data, 
such as the average temperature and the average pressure, by searching the 
term "U.S. Standard Atmosphere
(1976)" on the Internet. I prefer the search engine: www.google.com
     For this "standard atmosphere" the temperature does decrease by
6.5 C. / 1000 ft. Above about 10,800 ft the temperature of this "standard
atmosphere" is a constant -55 C. But keep in mind that these numbers are an
average of an enormous amount of specific observations for scientists and
engineers to use in constructing atmospheric models or designing aircraft.

Vince Calder
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