merge pressure and barometric_pressure terms

[only1chunts]

Current term details

Term name - pressure
Term ID - MIXS:0000412
Structured comment name - pressure
Definition - Pressure to which the sample is subject to, in atmospheres
Expected value - measurement value
Value syntax - {float} {unit}
Example -50 atmosphere
Preferred unit - atmosphere
Package(s) - 
   hydrocarbon resources-cores
   hydrocarbon resources-fluids/swabs
   microbial mat/biofilm
   miscellaneous natural or artificial environment
   sediment
   water

@lschriml says:

how is this different from barometric pressure?

Term name - barometric pressure
Term ID - MIXS:0000096
Structured comment name - barometric_press
Definition - Force per unit area exerted against a surface by the weight of air above that surface
Expected value - measurement value
Value syntax -{float} {unit}
Example - 5 millibar
Preferred unit - millibar
Package(s) - air

Suggested update(s) The only difference appears to be the packages the terms appear in and the expected units. Can we update barometric_pressure to include the possibility of accepting atmosphere units? Then merge these two terms together.

[lschriml]

OK with me. Lynn

[only1chunts]

Looking at this again, I think it perhaps needs wider discussion. Pressure MIXS:412 is talking about pressure on a sample, which can include air pressure but could also include pressure from soil or water, the barometric_pressure is a term used specifically for air or atmosphere, and is generally considered a predictory feature of weather systems. I believe the use of "pressure" in a sampling context will be more likely to be used, i.e. the pressure the sample was exposed to, rather than a general weather conditions indicator, so my vote would be to replace the barometric_pressure term with that of pressure. But I'm no expert in this field and have never done any sampling of things that any sort of pressure measurement would be relevant to! @lschriml , @ramonawalls do either of you know who would be a good person to ask for opinions on this?

[pbuttigieg]

If needed, I'd resolve this difference by having a single term for "ambient_pressure" (valid for any medium like air, water, etc).

This, in combination with what's in the env_medium term, should express what's exerting the pressure on the sample (this can be added to this term's definition/description).

If there's an experimental coniditions package created, one can have "applied_pressure", but I think that's redundant.

[lschriml]

Check on usage prior to considering a merge. Discuss for version 7.