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I'm developing an Android app which uses a pressure sensor. Due to storage limitations I have to normalize and scale the atmospheric pressure values. For this I need to know the extreme values of pressure.

Different conditions should be respected, e.g.

  • Weather conditions (low/high)
  • Locations (high mountains, deep valleys like Dead Sea with a surface elevation of: -427 m (−1,401 ft))

If this is unknown, does anybody know the range at sea level? Something like 1013 hPa ± X?

With a formula I've found I calculated that the pressure on Mount Everest should be something like 300 hPa and at Dead Sea about 53 hPa more than at sea level. But this is not a very complex formula, so these values might be theoretical and wrong.

Edit / additional info

I discovered that my sensor provides values like 980.01 hPa, so there are 2 digits precision (don't know whether this reflects sensor precision). A difference of 0.01 hPa means ~8cm altitude. This might sound little, but I need to calculate the current incline of athletes, so I cannot sacrifice precision. My current scaling algorithm produces normalized numbers from 0 to 32768. It would imply much work to change the output range.

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    $\begingroup$ How tight does this range need to be? As a practical matter, it might make sense to just go with 0-2026 hPa - this certainly captures all possible atmospheric pressures on this planet, and if you have 32 bits to store pressure values, you're probably not going to lose any data, since your pressure sensor is probably not that precise. (This wider range is certainly no more than 8 times as wide as the tightest possible range → it should cost at most 3 extra bits relative to a tighter range.) $\endgroup$ – senshin May 27 '14 at 14:16
  • $\begingroup$ @senshin I updated my question. Can you tell the maximum possible pressure? Do you think 1100 hPa is possible? $\endgroup$ – hgoebl May 27 '14 at 15:27
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    $\begingroup$ @hgoebl The highest surface pressure (unofficial) is 1092.1 hPa apparently measured somewhere in Mongolia. The official record is 1085 hPa in Siberia iirc. $\endgroup$ – casey May 27 '14 at 15:37
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    $\begingroup$ @casey Isn't that the pressure reduced to sea level? That's not the most relevant quantity for an actual sensor. $\endgroup$ – gerrit May 27 '14 at 16:29
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    $\begingroup$ @gerrit upon further review you are correct. Those are indeed corrected to MSLP (I was a bit quick in my initial investigation). Finding actual surface pressure records seems a bit harder than I thought as everyone corrects to MSLP so they can be compared. If the OP wants a hard upper limit it may be safe to take the (contested) MSLP record of 1091 hPa and hypsometrically find the corresponding pressure at the lowest elevation on earth. $\endgroup$ – casey May 27 '14 at 16:48
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Presssure at the Mt. Everest summit has been measured to be 253 Torr (337 hPa). http://jap.physiology.org/content/86/3/1062

Pressure at the Dead Sea as high as 1079 hPa is reported in Fig. 12 of this reference: http://isramar.ocean.org.il/isramar2009/DeadSea/Hecht&Gertman_2003_DS_Climate_Chapter4.pdf

As far as at sea level, 870 hPa was measured for typhoon Tip in 1979. http://www.wunderground.com/blog/weatherhistorian/world-and-us-lowest-barometric-pressure-records

And 1067 hPa at coastal areas of Estonia and Lativa are reported here: http://www.wunderground.com/blog/weatherhistorian/world-and-us-anticyclonic-high-barometric-pressure-records

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