[CF-metadata] PMIP Standard names: isotopic fluxes, mass contents and ratios.

From: Martin Juckes - UKRI STFC <martin.juckes>
Date: Tue, 3 Apr 2018 10:53:09 +0000

Dear All,

I would like to propose the following 12 standard names on behalf of the PMIP team. They all relate to water molecules containing stable isotopes of oxygen or hydrogen (17O, 18O, and 2H [deuterium]).

(1) pr18O: Precipitation mass flux of water molecules that contain the oxygen-18 isotope (H2 18O), including solid and liquid phases. [kg m-2 s-1]

There is no current CF construction to refer to water containing a specific isotope; the closest is ".._A_expressed_as_B", which refers to the amount of a component B in A. We propose a new construction "_A_containing_B" which refers to the amount of A which contains B:

precipitation_flux_of_water_containing_18O

(2) prsn18O: Precipitation mass flux of water molecules that contain the oxygen-18 isotope (H2 18O), including solid phase only. [kg m-2 s-1]

As (1), but for solid phase only. There does not appear to be a specific standard name construction for the solid phase of water, but "_liquid_phase" is used for the liquid phase, so "solid_phase" appears to be a natural extension.

precipitation_flux_of_solid_water_containing_18O

(3) pr2h: Precipitation mass flux of water molecules that contain one atom of the hydrogen-2 isotope (1H 2H O), including solid and liquid phases. [kg m-2 s-1]

As (1), but for 2H
precipitation_flux_of_water_containing_2H

(4) prsn2h: Precipitation mass flux of water molecules that contain one atom of the hydrogen-2 isotope (1H 2H O), including solid phase only. [kg m-2 s-1]

As (2), but for 2H
precipitation_flux_of_solid_water_containing_2H

(5) pr17O: Precipitation mass flux of water molecules that contain the oxygen-17 isotope (H2 17O), including solid and liquid phases. [kg m-2 s-1]

As (1), but for 17O
precipitation_flux_of_water_containing_17O

(6) prsn17O: Precipitation mass flux of water molecules that contain the oxygen-17 isotope (H2 17O), including solid phase only. [kg m-2 s-1]

As (2), but for 17O
precipitation_flux_of_solid_water_containing_17O

(7) prw18O: Water vapor path for water molecules that contain oxygen-18 (H2 18O) [kg m-2]

This proposal follows the pattern of mass_content_of_water_vapor_in_atmosphere_layer, with the "containing_18O" specialisation:

mass_content_of_water_vapor_containing_18O_in_atmosphere_layer

(8) prw17O: Water vapor path for water molecules that contain oxygen-17 (H2 17O) [kg m-2]

As (7), but for 17O
mass_content_of_water_vapor_containing_17O_in_atmosphere_layer

(9) prw2H: Water vapor path for water molecules that contain one atom of the hydrogen-2 isotope (1H 2H O) [kg m-2]

As (7), but for 2H
mass_content_of_water_vapor_containing_2H_in_atmosphere_layer

(10) sw18O: Ratio of abundance of oxygen-18 (18O) atoms to oxgen-16 (16O) atoms in sea water [1]

"Isotope ratio" is a widely used concept which is not yet represented in the standard name list. Isotope ratios are the ratio of one isotope to another, usually the most stable isotope (e.g. 16O for oxygen). In the standard names we propose a cautious approach of explicitly stating both isotopes in the ratio:

isotope_ratio_of_18O_to_16O_in_sea_water

The construction "isotope_ratio_A_to_B_" refers to the ratio of the number of atoms of A to the number of atoms of B.

(11) sw17O: Ratio of abundance of oxygen-17 (17O) atoms to oxgen-16 (16O) atoms in sea water [1]

As (10), but for 17O
isotope_ratio_of_17O_to_16O_in_sea_water

(12) sw2H: Ratio of abundance of hydrogen-2 (2H) atoms to hydrogen-1 (1H) atoms in sea water [1]

As (10), but for 2H
isotope_ratio_of_2H_to_1H_in_sea_water

regards,
Martin
Received on Tue Apr 03 2018 - 04:53:09 BST