Opened 3 years ago
Closed 3 years ago
#728 closed enhancement (fixed)
Too frequent zero LAI in time series
Reported by: | luyssaert | Owned by: | somebody |
---|---|---|---|
Priority: | critical | Milestone: | ORCHIDEE 4.1 |
Component: | Biogeochemical processes | Version: | trunc |
Keywords: | Cc: |
Description (last modified by luyssaert)
In r6904 the large scale LAI is starting to look OK but when zooming in on the time series this version still has many more years with a zero LAI compared to ORCHIDEE 3 and Tag 2.1. This may be caused by:
- Problems with phenology (only if phenology is in part driven by soil moisture). Possible for PFT3, 10, 11, 12, 13, 14 and 15.
- Problems with Rm. If Rm > GPP during the senescence phase the reserves and labile C pools will be empty by the end of the year resulting in zero LAI the next year.
- PFTs 10, 11, 12, 13, 14 and 15 hardly grow. The grasslands have a rather high within-season turnover which may explain their limited growth but this is suspicious for the crop PFTs and finding its cause could help to solve this ticket.
Change History (3)
comment:1 Changed 3 years ago by luyssaert
- Description modified (diff)
comment:2 Changed 3 years ago by luyssaert
comment:3 Changed 3 years ago by luyssaert
- Resolution set to fixed
- Status changed from new to closed
In r7272 mortality of the tree PFTs seems OK but this version has more mortality than ORC2 and ORC3. r7272 has a hard time to grow some of the tree PFTs outside their core area. This is probably OK (for example, the model fails to grow TropicalEvergreenBroadleaved? trees in the horn of Africa (which is bone dry and not a suitable place for this PFT).
Based on the mapper the LAI of PFTs10-15 is OK. The stoplight plots which also check for mortality confirm that PFTs12 and 13 are well simulated. PFT 10, 11 and 15 grows well in its core areas but still dies in the drier regions. PFT 14 mostly dies except for the wettest locations. Due to the frequent replanting this model version and parameters could be used in global simulations. A ticket will be made for Milestone 4.3 to further investigate the issue.
Problems with phenology (only if phenology is in part driven by soil moisture). Possible for PFT3, 10, 11, 12, 13, 14 and 15.
PFTs 10, 11, 12, 13, 14 and 15 hardly grow. The grasslands have a rather high within-season turnover which may explain their limited growth but this is suspicious for the crop PFTs and finding its cause could help to solve this ticket.
Problems with Rm. If Rm > GPP during the senescence phase the reserves and labile C pools will be empty by the end of the year resulting in zero LAI the next year.
In r7012 grasslands in arid and semiarid regions are subject to frequent dying, which is problematic. This causes further problem of frequent false uptake of GPP simply by prescribing new sapling biomass for grassland. This potential problem needs to be fixed. It may in part be related to simulating a wrong starting date and or a too short growing season (which does not leave enough time to restore the reserves).