Dear Chris and Martin,

Thanks for the discussion of proposals 21, 22, 23.

I think we are agreed to modify these as follows:
21: raStem surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_stems 
should be 

22: raLeaf 
surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_leaves should be 

23: raRoot surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_roots 
should be 

These names had already been accepted. I have now modified them to include 
'expressed_as' and inserted the appropriate sentence in the definitions. These 
names will still be included in the April 16th update.

Regarding the discussion of ra and raOther:

We have an existing standard name plant_respiration_carbon_flux which I think 
is the correct one to use for ra (ra = raStem + raLeaf + raRoot + rOther). This 
is why, originally, I didn't have the 'expressed_as' bit in proposals 21-23 - I 
was following the pattern of the existing name. In fact, we should now turn the 
existing one into an alias so that plant_respiration_carbon_flux becomes 
 for consistency with the new C4MIP names. Do you agree?

As far as I can see, we don't currently have a standard name (either existing 
or proposed) that would correspond to raOther. Do we need one for the CMIP6 
data request? If so, then we should do as you have both suggested and follow 
the standard name we have agreed for nppOther. It would then be something like 
the following:
 (kg m-2 s-1)
'The surface called "surface" means the lower boundary of the atmosphere. 
"Upward" indicates a vector component which is positive when directed upward 
(negative downward). In accordance with common usage in geophysical 
disciplines, "flux" implies per unit area, called "flux density" in physics. 
The chemical formula for carbon dioxide is CO2. The phrase "expressed_as" is 
used in the construction A_expressed_as_B, where B is a chemical constituent of 
A. It means that the quantity indicated by the standard name is calculated 
solely with respect to the B contained in A, neglecting all other chemical 
constituents of A. The specification of a physical process by the phrase 
"due_to_" process means that the quantity named is a single term in a sum of 
terms which together compose the general quantity named by omitting the phrase. 
"Miscellaneous living matter" means all those parts of living vegetation that 
are not leaf, wood, root or other separately named components.'

If we are turning plant_respiration_carbon_flux into an alias, there are some 
other existing respiration names that should also be updated to make them into 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon names:
heterotrophic_respiration_carbon_flux -> 
soil_respiration_carbon_flux -> 
surface_upward_carbon_mass_flux_due_to_plant_respiration_for_biomass_growth -> 
Do others agree? If so, I can add the aliases (and the extra name, if needed) 
in the April update of the standard name table.

Best wishes,

Alison Pamment                                 Tel: +44 1235 778065
NCAS/Centre for Environmental Data Archival    Email:
STFC Rutherford Appleton Laboratory     
R25, 2.22
Harwell Oxford, Didcot, OX11 0QX, U.K.

-----Original Message-----
From: Jones, Chris D [] 
Sent: 05 April 2018 13:13
To: Juckes, Martin (STFC,RAL,RALSP) <>; Pamment, Alison 
Subject: RE: New standard names for C4MIP - part 2

Sounds good on all fronts! Thanks

Dr Chris Jones
Head, Earth System and Mitigation Science Team Met Office Hadley Centre, 
FitzRoy Road, Exeter, EX1 3PB, U.K. 
Tel: +44 (0)1392 884514  Fax: +44 (0)1392 885681

-----Original Message-----
From: Martin Juckes - UKRI STFC []
Sent: 05 April 2018 13:09
To: Jones, Chris D <>; Alison Pamment - UKRI STFC 
Subject: Re: New standard names for C4MIP - part 2

Hello Chris,

thanks. The proposed standard name for raRoot (with the modification suggested 
in my Q1) is consistent with your answer to Q2, so I support going forward with 

Your answers suggest that there is a case for revisiting the standard name used 
for "ra", as it would be nice to have a consistent approach for ra and the 4 
new components, and we also need an additional name for raOther. I suggest we 
defer this to a separate discussion, so that Alison can move forward with the 
names agreed here,



From: Jones, Chris D <>
Sent: 05 April 2018 12:48
To: Juckes, Martin (STFC,RAL,RALSP); Pamment, Alison (STFC,RAL,RALSP);
Subject: RE: New standard names for C4MIP - part 2

Thanks Martin - good questions!

Q1 - that's a good point. Yes I think these should take that form too unless 
there's a reason not too - but yes, this is a CO2 flux into the atmosphere and 
we want it in terms of mass of carbon lost.

Q3 - I'll answer this first - yes, rOther is also required in parallel to 
nppOther. These are then sub-components of the total plant respiration: ra = 
raStem + raLeaf + raRoot + rOther

Q2 - that sounds rather nuanced! So, yes, "ra" is an existing variable, and 
these new ones are sub components of it (as per Q3). It would be much neater if 
we could label this (all components) as a flux to the atmosphere. Technically 
the respiration from roots goes happens under ground, but "into soil" is a very 
bad description because that implies the carbon goes into the soil carbon pool, 
rather than being CO2 gas within the pores of the soil. It eventually escapes 
into the atmosphere and I've never heard of a model which tries to simulate any 
sort of storage of CO" gas trapped within soil. So this would be better simply 
labelled as a flux to the atmosphere. Does that make sense?


Dr Chris Jones
Head, Earth System and Mitigation Science Team Met Office Hadley Centre, 
FitzRoy Road, Exeter, EX1 3PB, U.K.
Tel: +44 (0)1392 884514  Fax: +44 (0)1392 885681

-----Original Message-----
From: Martin Juckes - UKRI STFC []
Sent: 05 April 2018 08:25
To: Alison Pamment - UKRI STFC <>; Jones, Chris D 
Subject: Re: New standard names for C4MIP - part 2

Dear Alison, Chris,

I have a few questions about items 21,  22, 23:

21: raStem surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_stems:

22: raLeaf surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_leaves

23: raRoot surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_roots

Q1: Such terms, which relate to the CO2 flux into the atmosphere, are usually 
of the form "..flux_of_carbon_dioxide_expressed_as_carbon...".

Have you decided that the longer form is redundant here?

Q2: We also have an existing name "plant_respiration_carbon_flux" which is used 
for variable "ra", as in CMIP5. "plant_respiration_carbon_flux" is described as 
a mass flux of carbon into the atmosphere and soil: would it be safe to assume 
that the carbon respiration flux into soil is the component from the roots?  
Shouldn't this be something like 

Q3: there should be a name for "raOther" somewhere, which would follow the 
pattern established for "nppOther" in this discussion, but does "raOther" 
include fluxes into soil and atmosphere, as "ra", or is it just a flux into the 
atmosphere, as "raLeaf" and "raStem"?



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