further updates for ilamb pre-processing waiting on Romain for approving (currently O/S)
Agreed to go ahead with Australian PFT meeting for Friday. Discussed getting more clarity on which parameter values will be important / most sensitive - both in pft_params.nml and pftlookup file.
@RachelLaw shared canopy height slides - heights based on wood pool for trees and LAI for grasses. Grass pfts have seasonality but grid-cell canopy height dominated by tree height. Using different scaling factor to give taller c4 grass/crop than c3 grass/crop. @Jhan has run test with new canopy heights in vegfunc file produced by @lachlanswhyborn. Seems to be running stably. Looked at daily output for first month to see when results deviate. Occurs from first day so suggests canopy height being updated at start of run, not relying on canopy height from restart file (which was left at the original values). Need to confirm, then look for any impact over longer means.
@alexnorton showed progress on zeric/mesic distributions for Australia and how NVIS data has been processed to produce these distributions. Discussion of the resulting mesic fractions in Central Australia. Due to open mixed woodlands. Agreed to split these 50% to xeric and mesic rather than all to mesic. Considered how to merge with LUH3 data for change in land-use but expect to be reasonable to implement as so much of Australia is classified as non-forest by LUH3.
@RachelLaw showed slides with results from Jhanâs run using spatially dependent canopy height (but fixed via ancillary not interactive). Some changes in temperature, precip, wind speed. Wind speed changes most noticeable for grass/shrub/tundra areas where relative change in height can be reasonably large. Discussion of next steps and whether to try and make canopy height interactive - and what the impact would be under future conditions. Noted that if stayed with using ancillary then need to consider what dataset to use to create the ancillary e.g. long-term mean of LAI rather than individual year as currently used. Agreed that worth coding up interactive case since should be relatively simple but need to be careful about where it is updated etc.
Issue with code/restart for testing Australian pfts
Current status from Jhan:
⢠feat-Aust-PFTs-106 failed at dt=50
⢠Turning off LAIfeedback it worked
⢠BUT fields in restart looked sorta OK
⢠Tested without Aust PFTs in feat-test-mainB leads to same failure at dt=50
⢠Focused on feat-test-mainB to remove potential conflation of issues
⢠gLAI on first timestep seems to be issue
⢠multiple, alternative restarts work. Alternative to PI-02-WithLUH3VegetationMap_2025-03-14.astart, PI-02-WithLUH3VegetationMap.astart
⢠Remaking the Aust PFTs from any of these alternatives will (almost) certainly get passed the initial crash
⢠This is not a guarantee that there will be no further issues with Aust PFTs
Obviously we need to get this resolved ASAP.
@lachlanswhyborn has made new restarts but initial look suggests not what was expected (one file has Australian 2/4 replaced with 12/13 when wasnât expected). Also need to confirm that canopy height in restart not used as set to zero for 12, 13. Previous year tile fraction looks like LUH2 while current year looks like LUH3 - though previous year shouldnât be used without l_luc flag switched on. @lachlanswhyborn will create some more restarts and @Jhan will continue with test runs.
If not a restart problem, have we missed something in the code which is dependent on hard-wired vegetation type - presumably in CASA?
For ilamb prep, @inh599 has written script to adjust dates on files so that can compare difference sections of runs.
Parameters: Rachel and Alex are fine-tuning the âwish-listâ of most important parameters to send to WSU team - Laura Williams and Belinda Medlyn. They will provide trait data where available, Laura has an idea of how to map species-level data to our PFT classes. Juergen and Alex agree that we will need to do a global comparison of tree type PFT parameters following the new assignment of Aus PFT parameters, to ensure the ârelativeâ differences are sensible.
Restart file tests: Changed PFT 2 to 12, and PFT 4 to 13 across entire globe. This resulted in no change in screen temperature - considered a successful test. Next test is to limit the PFT changes just to the Australian region. Lachlan and/or Jhan should have results by next week.
Model test with global swap of 2/12 and 4/13 showing some odd behaviour for type 13. What have we missed?
Progress on parameter values
Vegetation distribution without Australian pfts. @alexnorton has prepared a new version, waiting on @RachelLaw to review.
Configuration âto doâ table. Review of land items.
Notes
PFT swaps:
Rachel: The GPP is collapsing (to 0) for PFT 13 after several years of simulation.
Lachlan: run with zeroing out the PFTs 2 and 4 is creating differences in the run while these have a tile fraction of 0.
It would be useful if the collapse is reproducible if starting the run on that year to make a shorter testcase to work with.
Alex: Is there any chance there is a PFT-dependence left in the coupling? Could we use Rachelâs single point simulations to track the issue? Or the offline CABLE code although it isnât in sync with ESM1.6 (Claire)
Parameter values:
Rachel working on the pftlookup file. Trying to identify the parameters we are using and we need values for.
Rachel: In the CABLE documentation, it would be good for the parameters to identified if they are used only with certain options.
Comparison of Walker with before for seasonal cycle of GPP, soil respiration, NPP and NEP. Big suppression of NEP boreal maximum.
NEP suppression in evergreen needleleaf. Suppression not seen in plant respiration. Massive increase in leaf respiration: Leaf respiration ratio to GPP is pushed to 0.5 which is way too high.
vcmax increasing by 2.5 times but leaf respiration increases by 8-9 times. Trying to figure out what is happening.
Other results seem to be ok with the Walker vcmax.
Ian: there could be some connection with the climate variables or other parts of the code that need to be brought in with the Walker vcmax calculations.
Juergen: worth checking the respiration and vcmax temperature response.
Alex: worth looking at tweaking the sla parameter to see the effect on the leaf respiration while still looking to explain what is happening.
Ian: from Jhan, it will not be easy to get vcmax out of ESM1.6. It wonât be easier in AM3.
Australian PFTs
2/12 and 4/13 swap is not collapsing GPP anymore, caused by using an old parameter file.
Jhan chasing down reproducibility. There may be MOSES parameters being used and making progress when parameters are made to agree
Alex sent list of parameters for input.
Rachel to review the veg. distribution with Aust PFTs and without to see if we want to set a min. fraction that is not worth simulating, as we have done in the past.
Before we used a 10% fraction threshold: a grid cell never reached more than 10% of that type with land use change. Alex: what was done with these 10% then? Rachel: it was distributed proportionally to other PFTs in the grid cell.
Rachel: issue with 10% on the coast lines though.
Alex: should we reduce the threshold instead of no threshold at all? Something like 1-3%.
Ian: Are the new PFTs evergreen:
Rachel: yes, the code assumes everything is evergreen unless there is something in the phenology file. Itâs the simplest for now to keep them evergreen.
Ian looked into the physical parameters but most important will be the bgc ones. (@inh599 edit: and biophysical trait parameters such as stomatal function)
@RachelLaw, lots of parameters are also completely unused, it would be best to get rid of them completely.
Swapping PFTs
2 runs,JuneSpinupStandard and JuneSpinupJuggle, should use the same except for the restart files. They still diverge very quickly. Nothing is looking crazy but it is different.
Question on what happens on the first UM radiation time step.
LUH3.1.1 data
Loss of temporal resolution in recent years. Decision from LUH data providers.
EGBL appearing in northern Russia: probably a bug to check
Tile fraction not quite summing to 1 at each time step. Problems in some Canadian tiles.
Changes between 3.1.1 and 3.0 for 1850:
Switch of EGNL to DNL in high latitudes. Also change noted in Tibetan plateau.
Reduced bareground, increase C4 grass in Australia
Decrease in trees and increase in grass in Europe.
Change between present day and 1850:
largest differences in DBL, more change from grass to crop