[CF-metadata] RE: Proposed acoustic standard names

From: Pamment, JA <J.A.Pamment>
Date: Thu, 27 Jul 2006 14:04:06 +0100

Dear Mike,

Thank you for your two sets of proposals for acoustic standard names. I have amalgamated my responses to all your proposals below.

> frequency: s-1 : inverse of period
I suggest that for clarity we modify this slightly to sound_frequency: s-1 to distinguish it from electromagnetic frequency and also from any statistical meaning of the word frequency.

> sound_intensity_in_air: W m-2
> sound_pressure_in_air: Pa
> sound_intensity_level_in_air: dB : decibels referenced to a sound
> intensity of 10-12 W m-2.
> sound_pressure_level_in_air: dB : decibels referenced to a sound pressure > of = 2 ? 10-5 Pa.
> sound_intensity_in_water: W m-2
> sound_pressure_in_water: Pa
> sound_intensity_level_in_water: dB : decibels referenced to a sound
> intensity of 6.7 x 10-19 W m-2.
> sound_pressure_level_in_water: dB : decibels referenced to a sound
> pressure of = 10-6 Pa.
These all seem fine to me - thank you for providing clear definitions.

> spectral_noise_level_in_air: dB : decibels referenced to a sound pressure > of 2x10-5 Pa divided by the square root of frequency in Hz.
> spectral_noise_level_in_water: dB : decibels referenced to a sound
> pressure of 1x10-6 Pa divided by the square root of frequency in Hz.
Since these quantities seem to be closely related to your earlier definitions of sound_pressure_level_in_air|water I wonder if it would be more consistent to use spectral_sound_pressure_level_in_air|water. Also, I am not sure that "noise" is the best term to use here because it could be interpreted as meaning unwanted noise as in "signal to noise ratio". Do you agree?

> mass_concentration_of_oxygen_in_sea_water: kg m-3 : Mass of dissolved
> oxygen per unit volume sea water.
I note Roy Lowry's concerns below - do we need a separate quantity in different units?

Roy Lowry wrote:

>I worry about 'mass_concentration_of_oxygen_in_sea_water: kg m-3' as we
> allready have 'moles_of_oxygen_per_unit_mass_in_sea_water' which is
> effectively the same thing, but in different units. If we start setting
> up standard names for each chemical species for the various combinations
> of moles/mass/per litre/per kilogram, we are likely to be overwhelmed.

Kind regards,
Alison

------
Alison Pamment Tel: +44 1235 778065
NCAS/British Atmospheric Data Centre Fax: +44 1235 445858
Rutherford Appleton Laboratory Email: J.A.Pamment at rl.ac.uk
Chilton, Didcot, OX11 0QX, U.K.
Received on Thu Jul 27 2006 - 07:04:06 BST