Earth Sciences and Ecology Question #912

DeeCee, a 46 year old male from Indianapolis asks on September 9, 2002,

Is there a standard formula that will convert altitude into pressure? I'm interested in altitude from sea level to approx. 500,000 feet. I would like to input this formula into a spreadsheet program.

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The answer

Barry Shell answered on September 15, 2002

A rule of thumb for altimeter correction is that the pressure drops about 1 inch of mercury for each 1,000 foot altitude gain. If you're using millibars, the correction is 1 millibar for each 8 meters of altitude gain. These rules of thumb work pretty well for elevations or altitudes of less than a two or three thousand feet.

For more details and a formula for your spreadsheet use Google to search the web. Many places have this answer, such as (scroll down the page).

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