Re: [CF-metadata] CMIP6 data request: Precipitation of solid phase water

[John Graybeal]

I agree with Martin, use solid for atmosphere and frozen for soil. It doesn’t 
jump out at me that solid water is (umm, almost?) always frozen, even though 
it’s obvious that frozen water is always solid. 

I think it would be useful if the definition listed the forms (and pathways) 
that solid water can take, so that those of us less atmospherically advanced 
will be able to appreciate what it’s meant to include.

john

---
John Graybeal
jbgrayb...@mindspring.com


> On Apr 6, 2018, at 23:49, Martin Juckes - UKRI STFC 
>  wrote:
> 
> Dear Jonathan,
> 
> 
> my vote would be to leave soil water terms unchanged and allow the use of 
> "solid" in the atmosphere.  There is sufficient difference between the 
> behaviour of water in soil and in the atmosphere to justify, in my mind, this 
> slight divergence in usage. After all, solid water from the atmosphere can 
> only become frozen soil water, I believe, by melting, sinking into the soil 
> and then re-freezing,
> 
> 
> regards,
> 
> Martin
> 
> 
> 
> From: CF-metadata  on behalf of Jonathan 
> Gregory 
> Sent: 06 April 2018 16:38
> To: cf-metadata@cgd.ucar.edu
> Subject: Re: [CF-metadata] CMIP6 data request: Precipitation of solid phase 
> water
> 
> Dear Martin
> 
> I agree with you that frozen_precipitation_flux seems a bit more surprising in
> some way than solid_precipitation_flux. If we put "solid" instead of "frozen",
> should we change (by alias) the existing names that have "frozen", which are
> 
> frozen_water_content_of_soil_layer
> lwe_thickness_of_frozen_water_content_of_soil_layer
> mass_fraction_of_frozen_water_in_soil_moisture
> mass_fraction_of_unfrozen_water_in_soil_moisture
> soil_frozen_water_content
> surface_frozen_carbon_dioxide_amount
> volume_fraction_of_frozen_water_in_soil
> 
> I'm sure there must be others with useful comments to make about this.
> 
> Best wishes
> 
> Jonathan
> 
> 
> - Forwarded message from Martin Juckes - UKRI STFC 
>  -
> 
>> Date: Fri, 6 Apr 2018 15:06:15 +
>> From: Martin Juckes - UKRI STFC 
>> To: Jonathan Gregory 
>> Subject: Re: [CF-metadata] CMIP6 data request: Precipitation of solid phase
>>   water
>> 
>> Dear Jonathan,
>> 
>> 
>> It may be that the situation of interest in soil is a change brought about 
>> by decreasing temperature, and that the nature of the resulting substance is 
>> somewhat complex because of the matrix of soil that is carrying it. In the 
>> atmosphere I feel that applying the term "frozen" is a bit of a stretch, 
>> though I agree that it would be possible to state that as our intended 
>> meaning within the CF convention. On the other hand, we already use "liquid" 
>> (as in cloud_liquid_water) and "vapor" for the other two phases, so there is 
>> an argument for sticking to the standard partition solid/liquid/vapor.
>> 
>> 
>> Taking your other comments into account, the term would be either 
>> "frozen_precipitation_flux" or "solid_precipitation_flux". 
>> "frozen_precipitation" looks misleading to me, but perhaps that is a matter 
>> of taste.
>> 
>> 
>> As you say, it would be good to hear other opinions (I'll be on leave for 
>> the next few days, and will pick up the discussion at the end of next week),
>> 
>> 
>> regards,
>> 
>> Martin
>> 
>> 
>> 
>> 
>> From: CF-metadata  on behalf of Jonathan 
>> Gregory 
>> Sent: 06 April 2018 14:38
>> To: cf-metadata@cgd.ucar.edu
>> Subject: Re: [CF-metadata] CMIP6 data request: Precipitation of solid phase 
>> water
>> 
>> Dear Martin
>> 
>> That's a good point about snow and ice. I think we should use modified help-
>> text to make clear that "frozen water" means any form of solid water. I can't
>> recall the reason for "frozen" rather than "solid" - I guess because it felt
>> more obvious, if less systematic. I think I'm happy to understand "frozen
>> water" as "water in the solid phase", however it got into that state. I 
>> wonder
>> if others feel differently.
>> 
>> Best wishes
>> 
>> Jonathan
>> 
>> - Forwarded message from Martin Juckes - UKRI STFC 
>>  -
>> 
>>> Date: Thu, 5 Apr 2018 17:29:08 +
>>> From: Martin Juckes - UKRI STFC 
>>> To: "cf-metadata@cgd.ucar.edu" ,
>>>   "j.m.greg...@reading.ac.uk" 
>>> Subject: Re: [CF-metadata] CMIP6 data request: Precipitation of solid phase
>>>   water
>>> 
>>> Dear Jonathan,
>>> 
>>> 
>>> I hadn't spotted the existing usage of frozen_water. My only reservation is 
>>> that for such names the help text says '"frozen_water" means ice', which 
>>> would exclude snow. The existing usages of "frozen_water" are all soil 
>>> 

Re: [CF-metadata] New standard names for C4MIP - part 2

[Jones, Chris D]

Yes, I agree with the need for raOther and the suggested names - thanks 
Chris

-- 
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 
E-mail: chris.d.jo...@metoffice.gov.uk  http://www.metoffice.gov.uk 


-Original Message-
From: Martin Juckes - UKRI STFC [mailto:martin.juc...@stfc.ac.uk] 
Sent: 12 April 2018 15:53
To: Alison Pamment - UKRI STFC ; Jones, Chris D 
; cf-metadata@cgd.ucar.edu
Subject: Re: New standard names for C4MIP - part 2

Dear Chris, Alison,


We do have a requirement for "raOther" in CMIP6, so please go ahead. But, for 
consistency with the others I think it should be "_due_to_plant_respiration_", 
rather that just "_due_to_respiration_", and include a phrase on plant 
respiration in the help text. I've checked some background, to fill in gaps in 
my education, and learned that fungi are no longer plants ... at least not in 
the strict sense of the accepted scientific classification system. In order for 
these standard names to be correct for the requested variables, which are for 
autotrophic fluxes, I think we should make clear that we are using "plant" in 
this scientific sense, rather than in the broader sense following the pre-1960 
classification. With this meaning, I think we can strengthen the statement 
about autotrophs since, as far as I can tell, all plants are autotrophs. The 
current help text for "plant_respiration_carbon_flux" implies that plants 
respire biomass, which doesn't look right to me.


The current text used in the description of "plant_respiration_carbon_flux" is: 
"Plant respiration is the sum of respiration by parts of plants both above and 
below the soil. Plants which photosynthesise are autotrophs i.e. "producers" of 
the biomass which they respire from inorganic precursors using sunlight for 
energy." Following the discussion below, I think it would be worth modifying 
this to: "Plant respiration is the sum of respiration by parts of plants both 
above and below the soil. It is assumed that all the respired carbon dioxide is 
emitted to the atmosphere. Plants refers to the kingdom of plants in the modern 
classification which excludes fungi.  Plants are autotrophs i.e. "producers" of 
the biomass using carbon obtained from carbon dioxide."


I agree with the suggestion on modification of names for surface upward fluxes,


regards,

Martin


From: Pamment, Alison (STFC,RAL,RALSP)
Sent: 12 April 2018 12:45
To: 'Jones, Chris D'; Juckes, Martin (STFC,RAL,RALSP); cf-metadata@cgd.ucar.edu
Subject: RE: New standard names for C4MIP - part 2

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 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_stems

22: raLeaf 
surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_leaves should be 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_leaves

23: raRoot surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_roots 
should be 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_roots

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 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration
 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:
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_respiration_in_miscellaneous_living_matter
 (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" 

Re: [CF-metadata] New standard names for C4MIP - part 2

[Martin Juckes - UKRI STFC]

Dear Chris, Alison,


We do have a requirement for "raOther" in CMIP6, so please go ahead. But, for 
consistency with the others I think it should be "_due_to_plant_respiration_", 
rather that just "_due_to_respiration_", and include a phrase on plant 
respiration in the help text. I've checked some background, to fill in gaps in 
my education, and learned that fungi are no longer plants ... at least not in 
the strict sense of the accepted scientific classification system. In order for 
these standard names to be correct for the requested variables, which are for 
autotrophic fluxes, I think we should make clear that we are using "plant" in 
this scientific sense, rather than in the broader sense following the pre-1960 
classification. With this meaning, I think we can strengthen the statement 
about autotrophs since, as far as I can tell, all plants are autotrophs. The 
current help text for "plant_respiration_carbon_flux" implies that plants 
respire biomass, which doesn't look right to me.


The current text used in the description of "plant_respiration_carbon_flux" is: 
"Plant respiration is the sum of respiration by parts of plants both above and 
below the soil. Plants which photosynthesise are autotrophs i.e. "producers" of 
the biomass which they respire from inorganic precursors using sunlight for 
energy." Following the discussion below, I think it would be worth modifying 
this to: "Plant respiration is the sum of respiration by parts of plants both 
above and below the soil. It is assumed that all the respired carbon dioxide is 
emitted to the atmosphere. Plants refers to the kingdom of plants in the modern 
classification which excludes fungi.  Plants are autotrophs i.e. "producers" of 
the biomass using carbon obtained from carbon dioxide."


I agree with the suggestion on modification of names for surface upward fluxes,


regards,

Martin


From: Pamment, Alison (STFC,RAL,RALSP)
Sent: 12 April 2018 12:45
To: 'Jones, Chris D'; Juckes, Martin (STFC,RAL,RALSP); cf-metadata@cgd.ucar.edu
Subject: RE: New standard names for C4MIP - part 2

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 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_stems

22: raLeaf 
surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_leaves should be 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_leaves

23: raRoot surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_roots 
should be 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_roots

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 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration
 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:
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_respiration_in_miscellaneous_living_matter
 (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 

Re: [CF-metadata] New standard names for C4MIP - part 2

[Alison Pamment - UKRI STFC]

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 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_stems

22: raLeaf 
surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_leaves should be 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_leaves

23: raRoot surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_roots 
should be 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_roots

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 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration
 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:
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_respiration_in_miscellaneous_living_matter
 (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 -> 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_heterotrophic_respiration
soil_respiration_carbon_flux -> 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_respiration_in_soil
surface_upward_carbon_mass_flux_due_to_plant_respiration_for_biomass_growth -> 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_for_biomass_growth
surface_upward_carbon_mass_flux_due_to_plant_respiration_for_biomass_maintenance
 -> 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_for_biomass_maintenance.
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

--
Alison Pamment Tel: +44 1235 778065
NCAS/Centre for Environmental Data ArchivalEmail: alison.pamm...@stfc.ac.uk
STFC Rutherford Appleton Laboratory 
R25, 2.22
Harwell Oxford, Didcot, OX11 0QX, U.K.


-Original Message-
From: Jones, Chris D [mailto:chris.d.jo...@metoffice.gov.uk] 
Sent: 05 April 2018 13:13
To: Juckes, Martin (STFC,RAL,RALSP) ; Pamment, Alison 
(STFC,RAL,RALSP) ; cf-metadata@cgd.ucar.edu
Subject: RE: New standard names for C4MIP - part 2

Sounds good on all fronts! Thanks
Chris

--
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
E-mail: chris.d.jo...@metoffice.gov.uk  http://www.metoffice.gov.uk 


-Original Message-
From: Martin Juckes - UKRI STFC [mailto:martin.juc...@stfc.ac.uk]
Sent: 05 April 2018 13:09
To: Jones, Chris D ;