Meeting Reports

On Wednesday, 16th November

With Nicolas, Juliette, Didier and Anne.

Regarding the venue of Anne, speaking about the coupled version of models. As done with Maureen, the coupling orchidee/inca is available, remains to be checked. A meeting is scheduled for the following monday between Karine and Anne to see what to do.

Invitation to participate to the "Retraite of CMC" the next two days.

Explanation and summary of the reconstruction using NMVOC as a proxy for N₂O emissions. Two methods were tested: the first one from 1970 to 2019 using the csv data, reconstruction per sector and per region; the second one from 1850 to 2019 using the proxy, reconstruction per region. It exists a slight difference in total emissions between the two.

=> Need to check where it comes from. 2 hypothesis: reconstruction from proxy uses the 2000's netCDF file as a reference and not the 1970's file (because 1970 is the year used for the reconstruction); the average of the eight factors calculated per sector doesn't correspond to the factor computed per region.

TO DO

• See the coupled configuration;
• Check where the difference between reconstructed emissions comes from;
• With Didier, black box model with land, ocean, ant emissions.

On Wednesday, 2nd November

Only with Nicolas.

Mainly focusing on N₂O reconstruction via proxy NMVOC. What I have done (using a increasing year per year ration for NMVOC and apply it on N₂O data) doesn't give good results.

New idea to use correlation between the two datasets, find the linear regression per region and use this equation to reconstruct the N₂O emissions. Looks better because the trend will be kept.

TO DO

• Continue linear regression idea (avoiding negative values in the reconstruction and discontinuities in 1970);
• Prepare slides for ESM2025 meeting (4th of November).

On Wednesday, 19th October

In person with Juliette, Didier and Nicolas.

Look on comparison of EDGAR inventory and the one of CEDS. Globally, their emissions are similar but if we look by sectors, there are different. In EDGAR, apparently, it could be better to drop fertilizers and biomass burning categories.

Use of NMVOC proxy: seems to be a good idea but have to drop some sectors already taken into account in orchidee dataset. NMVOC better than NH₃ because too related to agricultural sector, neither to CO because too related to industry, then NMVOC seem to be the less polluted by one particular sector.

TO DO

• Comparison of emissions (without soil emissions and fertilizers) and understood relationship between their subcategories;
• Have a look on geographical repartition (in order to see if patterns are similar);
• Proxy to recompute without soil emission and without domestic sector. (from 0 Tg/yr in 1750 to little in 1850);
• See with Anne to come into coupled model.

A few words on the next MERMAID meeting (December 14) with a presentation of N₂O cycle and my work (introduction with Tian graph).

On Wednesday, 5th October

In person with Didier and Nicolas.

Review of the latest results for the present day run (because Didier wasn't present at the last meeting), with:

1. Data used (BBG, NAT and ANT);
2. Results of vertical profiles and total loss for 2000 (year with an imposed rescaling at 316 ppb);
3. Results over the whole period (2000-2007) with vertical concentration, surface concentration, total loss and burden.

Show first result of countries/great regions repartition. Mainly, discussion due to a reduction in seasonality when removing soil emissions from the agricultural sector (with the help of a factor). Interrogation of which repartition country/great region to use: the EDGAR/Minx one (more precise and fine than the other two found in CEDS/Hoesly articles).

What to do before 1970? Discussion on reconstruction emissions for pre industrial period (from a proxy or with surface concentration + total loss):

• The idea of a proxy from NMVOC/CEDS could be interesting because the evolution of emissions seems to be similar between NMVOC and N₂O (by great regions and/or sectors).
• An other idea (but more atypical) could be to see the difference between burden and total loss to the atmosphere in order to determine the sources. And then, using natural and biomass burning emissions (considered as good), we can determine emissions from anthropogenic sources (globally, not sector by sector).

TO DO

• Continue to explore the CEDS inventory and the analysis by country (aggregate by great region and then use mask to reconstruct global emissions).
• Make a test: from total loss distribution and burden (of CMIP6 simulation): try to recover anthropogenic emissions.
• Use a proxy-like from NMVOC to reconstruct anthropogenic emissions from 1850 to 1970.
• Compare EDGAR emissions and CEDS emissions (global and by great regions).

The main objective of the coming weeks will be to have natural, biomass burning and anthropogenic emissions from 1850 to 1970 (in order to use them into the coupled model).

For the next ESM2025 meeting, maybe prepare some slides (on subject: Forcing data and emissions compiled and harmonized (i.e. any new forcing not available from CMIP6 - e.g. anthropogenic CH4 emissions) for use in XCA2 demonstration simulations)

On Wednesday, 21th September

In person with Juliette, Marion and Nicolas.

Presentation of recent results for the present day run, with:

1. Data used (BBG, NAT and ANT);
2. Results of vertical profiles and total loss for 2000 (year with an imposed rescaling at 316 ppb);
3. Results over the whole period (2000-2007) with vertical concentration, surface concentration, total loss and burden.

Oceanic emissions seem constant over 150 years: Marion says it is okay, because N2O concentration are not so modified with increase of temperature and so on.

Discussion about the rescaling factor: if it is too low, it means that emissions are low too; if the correction is too big, emissions are too important also.

TO DO

• Chart of CEDS without soil emissions category,
• Plot BBG emissions in same units than others graphs (meaning in Tg/yr)
• Invest if it is possible to recover input emissions from surface concentration and total loss (in order to better reconstruct emissions)

On Wednesday, 7th September

In person with Didier and Nicolas.

Now, simulation on pre industrial period is good. The pressure evolution seems to depend on temperature (sst) or anything else that does not correspond to pre industrial period (slight increasing around 2008).

Next week (or the one after), Anne will be invited to learn more about configuration/physics/radiative code and to converge step by step towards a coupled version.

TO DO

• make graph of evolution of loss (same as vmrn2o);
• run a simulation with some imposed year as 1980.
• continue to develop code for present days.
• keep in mind the work with large region (CEDS inventories, see Maureen).

On Wednesday, 24th August

In person with Didier and Nicolas. PDF support (see attached file ).

Resume of august simulations and work.

• Transformation of CEDS emissions: from 1970 to 1999, use of netCDF file 2000 with a factor per sector to create netcdf emissions. Notebooks Transform_2000nc_from1970_to1999_via_CEDScsv.ipynb and work_on_data_to_complete_sectors_with_unknows_categories.ipynb
• 2 simulations: L39.v03 as a base (pre-industrial, constrained to 285ppm), then pi_piscideeL (free, pre industrial, 40 years).

Results seem good regarding vertical pressure profile, total loss N₂O, pattern of emissions. Need to investigate more and continue.

TO DO

• Make graph of pressure for those two simulations,
• Continue piscideeL 5 years and compute mean of loss,
• Resume differences between former simulations,
• Re-create netCDF files with only manure_management (and not soil_emissions) for agricultural sector.

+ Meeting with Didier (Tuesday, 12th July)

In person with Didier.

Discussion of simulations and set-up to make.

Check N₂O loss in 1999 for v03 simulation (to be continued) and create pi_piscideeL run from it to turn 40 years (1980-2020, L means libre/free/not rescaled at 285 ppm).

Explanation of how to create ncfiles from 1970 to 1999 from 2000's geographical repartition and ratio computed with total emissions per sector (csv file). Once done, adapt ciclad's code to transform them on Incasflx 144x142 grid.

On Monday, 11th July

In person with Didier, Nicolas and Juliette.

Conversation on Workshop N₂O source in Toulouse (6-8 July) : very interesting to see different communities (observation, inversion, modellers)

First result with a decreasing total emission (from 285 ppm to 280 ppm in 20 years) : seems to be promising.

Reflection on what is needed in order to move to coupled system. Remembrance of deadlines and expectations for ESM2025 project. Land emission per year ok, Nicolas will ask to Sarah or Laurent to have same emission for ocean. After that, work with Thibault Lurton and/or Anne Cozic to adapt code.

How to reconstruct anthropologic N₂O emission between 1850 and 1970 ? Try to find some proxy (population or chemical species that exists during this period)

TO DO

• Reconstruct N₂O emission with CEDS inventory with rescaling year by year (height with total budget and spatial with year 2000)
• When all is fixed, simulation from 1970 to 2015 in order to see if the model is coherent or not (with a rescaling at ~300ppm : CMIP6).
• Find information on Japanese model (the one of Prabir Patra)
• Get more information on Pisces simulation (does it use flag or many change in order to have it? Is it possible to have emissions per year from pre-industrial to present time?)

Next

• Computation of loss rate
• Coupled model (with Anne and Thibaut)

On Wednesday, 29th June

In person with Didier and Juliette + in visio with Marion.

Explanation of the remapping problem with pisces' file. The common CDO functions doesn't work (not conservative + white columns or column with outliers).

Solution : See Germain if he has some same files (grid 294x362 and not 292x292) + in correspondence with O. Marti for a better interpolation. work in progress

TO DO

• Understand and find a solution to the remapping problem.
• Send an e-mail to Sarah Berthet, in charge of different projects on N₂O : could be seen during the N₂O workshop in Toulouse (from 6th to 8th July).
• Simulations in 39 layers with invariants outputs in two different configurations.
• On profile picture, try to invert axis + use logarithm scale.
• Check availabilities for next meetings.

+ Meeting with Didier

• See different scripts to compute the N₂O-loss and N₂O-burden.
• Show what and how to change Incasflx files in order to use a irregular grid as input (avoiding the remapping problem).

On Wednesday, 15th June

In person with Nicolas and Didier.

Waiting for the first result with the 39-layers configuration.

After the General Assembly of ESM2025, pisces emissions seems to be too high... In fact, there was a problem of units conversion (mostly because of a misunderstanding of input units (mol N rather than mol N₂O).

Nicolas asked if lightning is implemented because it seems to have an total emission between 0.5 and 2 Tg/Nyr?.

Some works will be presented during the N₂O workshop in Toulouse from July, 6th to 8th.

To DO

• Analyse the vertical profile when the 39-layers configuration of one year is done.
• + See Didier for the next steps.
• Re-compute the calculation with the good value of pisces emissions.

On Wednesday, 1st June

In person with Nicolas, Juliette, Didier. Special guest : Anne.

Special demands to Anne :

• Passage from 79 layers to 39 : is it easy and feasible ? Seems to change some configuration's files (oxidants for example).
• svn for INCA ok, if need to change orchidee's sources, ask to Nicolas (but no need for this moment).
• Make some time series for long run test (feasible with the training course),
• Add output variables that would be computing into the code (have to see Anne when it will be time).

Show results on Bouwman (with aqua and soil flux): slight difference again. Using mask 0/1 (and not fractional one) is better.

Show on-going result of CEDS inventory (from McDuffie?): problem with units, needs to calculate annual mean to correspond to article's images.

To DO

• Finish charts of CEDS inventory. Notebooks used: CEDS_charts_supplementary_data_N2O.ipynb and Charts_N2O_CEDS.ipynb.
• Schedule a meeting with Didier when 39 layers' configuration is ready.
• Make simulation with oce and soil flux for Bouwman (not with aqua !!).

On Wednesday, 18th May

In person with Juliette, Didier, Nicolas.

• Notebook Budget_inventories : total budget of N₂O emissions (in tables), differences found between outputs INCASFLX and calculations in notebook (with mask, area and change units), different charts (by latitude, by land/ocean part, with histograms...)

Using the mask with fraction:

FracMask?	- Output INCASFLX -			- Notebook computing -
(Mt/yr)	Ocean	Land	Ratio O/L	Ocean	Land	Ratio O/L
Bouwman	5.650486	11.83547	0.478	13.967	16.726	0.835
	32.3%	67.7%		45.5%	54.5%
Transcom	6.634	16.614	0.399	8.879	14.421	0.616
	28.5%	71.5%		38.1%	61.9%
Piscidee	6.432	7.107	0.905	6.579	6.989	0.941
	47.5%	52.5%		48.5%	51.5%

Using the mask with 0/1 values:

0/1 Mask	- Output INCASFLX -			- Notebook computing -
(Mt/yr)	Ocean	Land	Ratio O/L	Ocean	Land	Ratio O/L
Bouwman	5.650486	11.83547	0.478	12.797	17.899	0.714
	32.3%	67.7%		41.7%	58.3%
Transcom	6.634	16.614	0.399	8.118	15.184	0.535
	28.5%	71.5%		34.8%	65.2%
Piscidee	6.432	7.107	0.905	6.174	7.395	0.834
	47.5%	52.5%		45.5%	54.5%

Those differences can be explained by the different power that may exist between marine or continental fluxes at coasts notably. With mask, these two fluxes have the same importance so it changes total flux.

Values per latitudes:

(Tg/yr)	90-30S	30S-0	0-30N	30-90N	Total
Bouwman	5.728	7.115	9.948	8.392	31.183
Trancsom	2.714	7.432	8.762	4.857	23.765
Piscidee	1.736	4.413	4.392	3.302	13.843

Calcul file by file: From Transcom (orchidee+pisces) : (no mask + not output of sflx) -> correspond to values of table 2 thompson part 1.

	- Output INCASFLX -			- Notebook computing -
(Mt/yr)	Ocean	Land	Ratio O/L	Ocean	Land	Ratio O/L
Transcom	6.634174	16.61481	0.399293	4.23125	10.59692	0.399291

Transcom is not a pre-industrial inventory, it's actual. So, it's better to work with piscidee inventory.

To DO

• Modify Bouwman run to take only 'oce' and 'soil' variables -> relaunch notebook to compare if it's better,
• Continue modification in INCA's code.

+ Meeting with Didier (Friday, 13th May)

Informal with Didier.

Preparation to change INCA's code in Irene.

• Modify inca.card to take new NAT files and BBG from ciclad.
• Modify mksflx_p2p.F90 to put flx_n2o_ant to zero and add aflux terms.
• Modify sflx_inti.F90 to take into account BBG emissions.
• Modify set_ub_vals.F90 to rescale N₂O flux (with parallel part and constant N₂O flux at 285 ppb)

Launch different runs in order to check each step.

Next

• Change ANT in ciclad,
• Put flx_n2o_ant to 0,
• Erase the rescaling,
• Add N2O loss as an output...

On Wednesday, 4th May

In person with Juliette and Marion.

• Presentation of the Wiki page.
• Presentation of the two notebooks.
• Discussion on the different conceptions used in ocean and land communities (different grids, different units in the flux (mol/m2/s vs kg/m2/s)...).

On Analyse_3_sflx_NAT_dyn.ipynb, discussions on visualization with scale, calculation of the full emission on earth per year or per month.

To DO

• Make an analysis per month, per hemisphere, in order to get the total flux emissions for each inventory.
• Take information on where the inventories come from (especially Bouwman and Transcom).
• Draw tables which resume datas used, total emissions, models used in files...
• Compare native grid and regular grid for pisces.
• Compare values of each file used with outputs of INCASFLX.
• Compare total emissions on ocean and land with literature (ciais, ippc) and Bouwman and Trancsom inventories.

On Wednesday, 20th April

In person with Nicolas.

Discussion on:

• New page on Wiki/igcmg (this one !)
• Explanation of the created notebooks (Data_viewer and Analyse_3_sflx_NAT_dyn)
  • Data_viewer : interactive ok but add choices/texts...
  • Analyse_3_sflx_NAT_dyn : change the seasonal analysis made.
• Test with Nicolas' network to know about access to my notebooks.
• Speak about dods/orchidee to avoid downloading images on wiki.

Now, focus on N2O with long living time, but after, we can test on other compounds.

To DO

• Change colorbar with mean+/-std, add some texts on Notebooks and add units on charts
• Erase rescaling in Bouwman to have a better comparison
• Analyse the 3 datasets in a different way : global tables with sum per year, per region, per type (ocean/land) (watch out units)
• Give "procedure" and access to notebooks to all
• Compare with Auburn data (and Tian 2020)
• Look at Mendeley (or Zottero) for bibliography

Nicolas: Paths to have regional masks (from Transcom)

On Wednesday, 6th April

In Visio with Nicolas, Juliette, Didier, Marion.

Mainly, this meeting was to talk a bit more about the project and the work I(=Karine) can make before the training session (April 14th & 15th).

Discussion on:

• the first result made with INCAFLX and 3 different inventories,
• the planning we can set up (which kind of simulation...)
• the impact of N2O on chemistry (if everything is coupled),
• the certainty (or uncertainty) of inventories used (to determine an appropriate scaling),
• the work of Pierre for aquatic emissions (importance of river emissions),

Planning : Run simulation without chemistry and no rescaling, first for pre-industrial, then until now to see/understand the correction we can make on both period (a different correction for each period).

=> This have to be detailed and confirmed

Maybe run only 10 years to know where are sinks, determine some lifetime/seasonal cycle in order to calculate the scaling we may use.

Suggestions to work with the GES branch for the code (branch for coupled model with CO₂ , CH₄ and N₂O)

Meeting every 2 weeks same day, same time (ie, Wednesday at 10:00)

To DO

• Ask for writing a Wiki page on IGCMG
• Log on JupyterHub?
• Make an "experiment plan" for future simulations
• Analyse the results that I've already (seasonal analyses, comparison between inventories with Bouwman as a reference, recap origin/grid resolution...)
• Show the aquatic variable of Bouwman (and maybe some others)

Didier : emissions file for pre-industrial fires to be send to Karine