Opened 15 months ago

Closed 9 months ago

#582 closed defect (fixed)

Low GPP for MTC6

Reported by: luyssaert Owned by: somebody
Priority: critical Milestone: IPSLCM6.v2
Component: Biogeochemical processes Version:
Keywords: Cc:

Description

The current parameetr values result in a reasonable LAI and GPP for MTC6 in North America but the GPP is about 30% too low for this MTC in Europe. Water stress is comaprable in both regions as is the LAI. Increasing K_LATOSA did not result in a higher GPP. This response may hint at N-limited growth over Europe. Increasing NUE_OPT had a small effect (an increase of about 70 g C m-2 y-1 in some parts of Europe), increaseing DECIDUOUS_RESERVE did not affect model behavior fundamentally. A limited impact of NUE in combination with DECIDUOUS_RESERVE is to be expected due to the sugar loading control in this model version. If NUE is increased but there is not enough N, the C pool in the reserves and labile pools will increase. If those pools exceed the target (partly determined by DECIDUOUS_RESERVE) sugar_load will downregulate the NUE. Can we increase N mineralization for this PFT?

Change History (3)

comment:1 Changed 11 months ago by jgipsl

  • Priority changed from major to critical

comment:2 Changed 9 months ago by luyssaert

r6432 was run with water stress and FM=2 to compare some basic variables (LAI, GPP, NPP) between EU and Eastern USA. All PFTs now behave similar in both continents and the spatial patterns are similar to the standard TRENDY S3 simulation for 2019.

The source of the earlier observed differences in behavior between the continents likely came from inconsistencies in the use of veget_max between hydraulic_arch and diffuco_trans_co2 and sechiba.

Last edited 9 months ago by luyssaert (previous) (diff)

comment:3 Changed 9 months ago by luyssaert

  • Resolution set to fixed
  • Status changed from new to closed
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