Sea Level vs. Absolute?

[rellis]

I am confused. I find definititons on the web that define Sea Level Pressure as what the pressure would be at my elevation strictly due to the elevation change from sea level, and independent of weather changes. Based on that, by living at 6,540ft, I found through three different sources that my Sea Level Pressure is 23.55 inHg. So far so good.
Then I read in the manual that the Absolute Pressure shown on the watch reflects elevation and weather changes, implying that the Sea Level reading is based simply on elevation.
So, I try to set the Sea Level pressure to 23.55, but as soon as I go below 27.25, I get "def" (which I realize is a factory default).
So how do I tell the watch that Sea Level Pressure for my elevation is 23.55?

The only other thing I can think of is that I am supposed to be setting the big number in the middle of the screen (right under where it says "Sea") to the ACTUAL barometric pressure at a given moment at my location per a local weather station. That I can do, but that sounds to me, based on Suunto's definitions, that I am setting ABSOLUTE pressure, not SEA LEVEL pressure.

Where have I lost it here? If it's just a matter of semantics and/or Suunto's definitions not matching things on the web, so be it. I just want to set the **** thing correctly...

Thanks in advance!

	Suunto Visit SuuntoWatches.com to see Suunto's full line of wrist top computers and compasses.

[Janice]

Let me try to explain..

The first screen on baro mode shows ABSOLUTE pressure. This is the actual air pressure in any location at any given time. It is dependent on the weather and altitude.

The only thing that you can reference (change) in your watch for the barometer is the SEA LEVEL pressure.
Whenever someone looks at the news station, the airport, or the weather channel online, the "Barometric pressure" given is ACTUALLY your SEA LEVEL pressure. (NOBODY gives the absolute pressure because it is different from every 5 feet of each other).

What a barometer does, is it measures the absolute pressure (ie 26.60) and then adjusts it for SEA LEVEL (ie 29.90) so that everyone in that given location is at the same standard. Sea level basically takes out the effect of elevation on your barometer.

So, you are going to look on a website and find your barometric pressure. You adjust it in the "SEA" mode in the barometer mode. There are 3 "DEF" = defaults. This means there is a high, low, and middle default where you cannot actually adjust it beyond or below what your watch actually senses is your barometric pressure (ie you cannot "trick" your watch into thinking you are at an altitude which you are not).

For most accurate results, you want to reference your ALTITUDE, not your barometer. (referencing the barometer will only birng you into a ballpark range of what your altitude is. Referencing your altimeter is actually the most accurate, based off a map).

It is a hard concept to explain through email, you might want to call Suunto's helpdesk which is available 24 hours.

	Suunto Visit SuuntoWatches.com to see Suunto's full line of wrist top computers and compasses.

[rellis]

A very useful response. Thank you so much.
As for the accuracy question, I don't care about elevation, so I use the watch in barometer mode.

[Janice]

You are very welcome!

[From_Chile]

I read the answer posted here about this topic and almost all my doubts are solved. But I still have a problem, I use both the altimeter and the barometer so I set the barometer according with the weather report (1012 HPa) and then i try to set the altitude (i know exactly the altitud here 750 mts) but automaticaly the barometer changes the value??? How can i fix the two figures? Thanks

JJ

[eyecon82]

Originally Posted by From_Chile

I read the answer posted here about this topic and almost all my doubts are solved. But I still have a problem, I use both the altimeter and the barometer so I set the barometer according with the weather report (1012 HPa) and then i try to set the altitude (i know exactly the altitud here 750 mts) but automaticaly the barometer changes the value??? How can i fix the two figures? Thanks

JJ

Hi..i also have a somewhat same question


currently I am at 709ft elevation with a 1002hPa.....just checked the national weather service

however, i keep setting my elevation to 709ft and the darn thing keeps jumping back up to 715ft...

In order to get it actually set to 709ft, I have to set it for 705ft and then it stays at 709ft....

what in the world is going on here?

I must admit, I am a beginner in this stuff. I recently got this watch as a gift and want to learn more about it. I read the whole manual and understand alost everything, but this is starting to bewilder me...

thanks for your help