CABLE4 planning: meeting notes

This topic records meeting notes and action items from weekly CABLE4 planning.

January 25th 2024

For discussion (progress on tasks, questions, issues etc)

  • Meeting structure @RachelLaw
  • Dominant tree type per grid-cell: pros and cons @inh599

Notes

  • Initially work on 3 tile version only for ACCESS implementation but need to be careful not to lose non-POP multi-tree, multi-grass pft capability.
  • Choose how to treat shrubs. Probably need to treat as a tree not a grass. Already being treated as woody in POPLUC.
  • POPLUC currently all vegetated or not. Should be able to handle a vegetated fraction to allow for fractional bareground, lake, ice, urban. Note that ACCESS currently does not allow fractional ice; grid-cell has to be all ice - possibly inherited from what JULES does.
  • Will need to consider how LUH2 (or update) data gets used in the POPLUC-ACCESS workflow.
  • Treatment of crop information from LUH2 will need consideration. Current POPLUC implementation may not be incorporating temporal change.

Actions

  • @RachelLaw to look at grassy types and how many exist in a single grid-cell. Bare ground needed for dust. Should be able to handle a bare ground fraction and lake, ice, urban.
  • LUH2 processing code to be copied from x45 to NRI space. @clairecarouge or team
  • @juergen to check crops from current Trendy experiment
  • Separate executable/inline code discussion scheduled for Feb 1. Let @clairecarouge / @inh599 know if any you have relevant input for consideration.
  • @RachelLaw to cancel Feb 8 meeting (AMOS)

February 1st 2024

For discussion

  • CABLE-POP at ACCESS resolution - next steps.
  • Has CABLE-POPLUC been run globally for future scenarios or higher than present-day CO2 concentration?

Notes

  • All files needed for CABLE-POPLUC now copied to rp23. Run not yet tested.
  • @Jhan tried running code with POP switched on from standard branch but need to use separate CABLE-POP branch. Use CABLE-POP-TRENDY branch.
  • No POPLUC dynamics depends on whether c3/c4 - only photosynthesis. So potential to composite grass types when pass to POP. Anything to be considered in LUH2 e.g. harvest fraction.
  • POP has been run for future scenarios (without LUC). Disturbance frequency kept constant. Could look at stress mortality outputs and impact on NPP. Australian work is showing mass die-back and recovery in some areas. Could be ‘quirk/bug’. May be fixed in CABLE-POP-TRENDY branch. Alison looking at in Australian case.
  • POP hasn’t been run with phosphorus on. Will need to re-visit this. Also performance in ACCESS and whether would benefit from recalibration with newer datasets.
  • Offline (CABLE-POP) runs also useful for tuning/calibrating nutrient cycles etc.
  • What do we need/want for evaluation on land? Standardised/automated. Think about this for Hackathon. Also making use of ILAMB. Involvement of Land Working Group - and ESM working group.
  • Separate executable has implications for offline runs as well.

Action

  • @clairecarouge to try a test run of CABLE-POP. @juergen available to help with error messages.
  • ~8 variables at daily resolution. Have these all been cmorised? @inh599 to confirm what is available and what to run (from ESM1.5 or AM3). Note grid shift between ESM1.5 and AM3 so will need two offline set-ups to match the two grids.
    Done. Details here: Run CABLE-POP at ACCESS Resolution - #2 by inh599
  • Other input files/ancillaries will need to be reconciled in a staged process including gridinfo. Gridinfo may have been derived from ACCESS. @Jhan to check - also how ancillaries have been updated for AM3.
  • @clairecarouge and team to look at formatting of ACCESS meteorology and changes required from cmorised files for CABLE-POP to read.

February 15th 2024

Previous actions status

  • land-mask split with R converted to Python. @clairecarouge continuing with next steps with @Juergen 's support. Different solution will be required in ACCESS implementation.
  • gridinfo: @Jhan has had a look. Need to confirm where inputs/ancillaries are different or the same between offline/online. @jhan to write summary.

For discussion

Notes

  • Proposal to create ‘cable tools’ to gather splitting/merging tools, pre/post processing.
  • Systematic test of with/without diffuse fraction to check sensitivity
  • Checking datasets for portability across CABLE-POP and ACCESS and which datasets we need to use from each configuration.
  • Conversion of restart files between offline/online. What are the critical fields that need to be passed between configurations.

Action

February 22nd 2024

Previous actions status

For discussion

Notes

  • C3/C4 split at spin-up time is limitation. Do we want to let this change over time as climate changes? Is there a need for mix of c3/c4 grasses in a grid-cell. Is the c4 fraction capability in CABLE still functional? Better to have the functionality to carry different grass/crop types in a grid-cell. Will have deal with how to manage transition and what is happening in the soil under each type within ‘grass’.

Action

  • Discussion on design for e.g. multiple types within grass @inh599 @Juergen @bens
  • @RachelLaw to plot some ACCESS/POPLUC comparisons at individual locations over full timeseries.
  • POPLUC output to be checked against input. Crop appears not to be changing.

A post was merged into an existing topic: Run CABLE-POP at ACCESS Resolution

February 29th

Previous actions status

  • ACCESS/POPLUC landuse comparisons at a location (@RachelLaw )
  • Does ACCESS resolution gridinfo exist? What did YPW pass onto @clairecarouge ?

For discussion

  • high level configuration options - 17 vs 27 tiles (@inh599 )

Notes

  • SW WA does look odd. Most land use change in 1960s seems OK if a decade early. 2000 onwards looks odd. States and transitions should be consistent. Might be better to start with the states and determine transitions from that but need to consider further.
  • ACCESS resolution gridinfo available on rp23. Also need to check whether it is on ESM1.5 or CM2 grid. Location of the files on N96 grid can be found here: crujra config at N96.
  • @inh599 - UM limitations on number of tiles, mostly due to UKCA coding. Decision is important now for AM3 work.
  • @inh599 started thinking about multiple grass types and will organise meeting.

Action

  • @Juergen to check POPLUC after 100 years to see how compares with LUH2.
  • @inh599 to talk with Peter Briggs about how LUH2 processed for POPLUC.
  • Audit of where tile/pft types are hard-coded across trunk and CABLE_POP branches. LS team.

Further information regarding the top level discussion around number of tiles:


@Jhan is attempting to run a 27 tile version of the proto-type AM3 to assess memory considerations.

March 7th

Previous actions status

For discussion

Notes

Action