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Talk:Geopotential height

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At an elevation of h

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What kind of elevation is "h" here? It doesn't seem to be geometric elevation, as that is z. It doesn't seem to be geopotential height/elevation either since the second formula defines that as Zg(h) rather than just h. Oh, and is elevation and height synonyms here or is there some subtle difference? Drhex (talk) 08:35, 14 August 2017 (UTC)[reply]

hPa?

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What does hPa mean? Plinth molecular gathered 21:06, 19 March 2007 (UTC)[reply]

It's a unit of pressure, in this case a gas pressure. hPa = hecto Pascals = 100 Pascals ≈ 1 millibar. Deditos 12:33, 21 June 2007 (UTC).[reply]

Request for more info for general reader

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This article gave me a very clear idea of the definition of geopotential height. But it'd be nice to have some more data to give a feel for how it differs from geometric height. How much does it differ? Does the difference vary from place to place? Is the difference typically an offset? Or is it a more complex function of geometrical height? I'd love to see a map of how it varies across the world. 216.239.45.4 (talk) 22:33, 12 September 2011 (UTC)[reply]

I second this. I'm at this article because I'd like to better understand meteorological charts which shows winds at different levels of hPa. That is, at about what heights are 1000hPa, 850hPa, 700hPa, 500hPa, 250hPa, 70hPa and 10hPa? If such a table cannot be included here, can there be a See also to this information? 92.0.230.198 (talk) 09:42, 24 July 2015 (UTC)[reply]

formatting

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the math fonts in the text are not the same as the fonts in the equation.

please allow editing so I can fix this.

I makes it more difficult to read especially for newbies — Preceding unsigned comment added by Adinov (talkcontribs) 02:34, 21 December 2011 (UTC)[reply]

Geopotential vs geometric height

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The current version says that geopotential height is more useful in equations than geometric height, and that it eliminates centrifugal force as well as air density which is hard to measure. This isn't exactly correct (see any meteorology textbook). First, the distinction is geopotential height as a function of pressure (isobaric coordinates) instead of pressure as a function of height (geometric coordinates) - geopotential height and geometric height are equivalent for virtually any atmospheric phenomena in the troposphere (the two differ only due to variations of g with height). Second, centrifugal force isn't eliminated with this coordinate transform. Third, air density is indeed eliminated, but it's not really relevant that it's hard to measure - the elimination is done assuming hydrostatic balance, so it only requires the pressure measurement that is used in either coordinate system. I'll now make revisions to the article to correct these points.--Abc-mn-xyz (talk) 06:19, 12 February 2013 (UTC)[reply]