Phenology Triggers (ctsm51_cesm23a16bctsm51d130_ne30pg3ne30pg3mg17_GSWP3V1_SturmSnowtk_decidphenotrig_1850)

[wwieder]

Description: Are seasonally deciduous phenology triggers preventing arctic green up?

Relaxing requirements for any/all of these switches in the seasonally deciduous phenology triggers may let plants start greening up earlier. See suggestion in extra details, below.

I'd build on the Sturm case, #10

• starting an AD spinup with initial conditions from the postAD Sturm run
• setting reseed=.true.

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Case directory: Locally: /glade/work/oleson/cesm2_3_alpha16b/cime/scripts/ctsm51_cesm23a16bctsm51d130_ne30pg3ne30pg3mg17_SturmSnowtk_decidphenotrigGSWP3V1(1850AD, 1850pAD, 1850)

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Sandbox: Locally: /glade/work/oleson/cesm2_3_alpha16b

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usernl changes: hist_fincl1 = 'TOTECOSYSC', 'TOTECOSYSN', 'TOTSOMC', 'TOTSOMN', 'TOTVEGC', 'TOTVEGN', 'TLAI', 'GPP', 'CPOOL', 'NPP', 'TWS', 'H2OSNO','NDEP_TO_SMINN' use_c13 = .true. use_c14 = .true. use_c13_timeseries = .true. use_c14_bombspike = .true. fsurdat = '/glade/work/slevis/git/mksurfdata_toolchain/tools/mksurfdata_esmf/surfdata_ne30np4.pg3_SSP5-8.5_78pfts_CMIP6_1850-2100_c230227.nc' finidat = '/glade/scratch/oleson/archive/ctsm51_cesm23a16bctsm51d130_ne30pg3ne30pg3mg17_GSWP3V1_SturmSnowtk_1850pAD/rest/0401-01-01-00000/ctsm51_cesm23a16bctsm51d130_ne30pg3ne30pg3mg17_GSWP3V1_SturmSnowtk_1850pAD.clm2.r.0401-01-01-00000.nc'

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SourceMods:

src.clm/atm2lndType.F90: Add some additional history fields src.clm/clm_varpar.F90: nlevurb=5 -> nlevurb=10 src.clm/surfrdMod.F90: Remove read of PFTDATA_MASK src.clm/Wateratm2lndType.F90: Add some additional history fields src.clm/SoilTemperatureMod.F90 Sturm Snow tk src.clm/CNPhenologyMod.F90 decreasing temperature thresholds to -3C, reducing the minimum critical daylength by 25%, doubling the snow threshold (I think to 20 cm)

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Diagnostics: Diags (if available)

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Output: Output: /glade/campaign/cgd/tss/common/Land_Only_Simulations/CTSM52_DEV/ctsm51_cesm23a16bctsm51d130_ne30pg3ne30pg3mg17_SturmSnowtk_decidphenotrig_GSWP3V1_1850AD/ /glade/campaign/cgd/tss/common/Land_Only_Simulations/CTSM52_DEV/ctsm51_cesm23a16bctsm51d130_ne30pg3ne30pg3mg17_SturmSnowtk_decidphenotrig_GSWP3V1_1850pAD/ /glade/campaign/cgd/tss/common/Land_Only_Simulations/CTSM52_DEV/ctsm51_cesm23a16bctsm51d130_ne30pg3ne30pg3mg17_SturmSnowtk_decidphenotrig_GSWP3V1_1850/

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Contacts: @olyson @wwieder

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Extra details: I'd just do this with a branch or source mods in CNPhenology

The suggestions below should are just for testing, but would be simple to impliment:

• decreasing temperature thresholds to -3C,
• reducing the minimum critical daylength by 25%
• doubling the snow threshold (I think to 20 cm)

       else if (season_decid_temperate == 0 .and.  onset_gddflag == 1.0_r8 .and. &
              soila10 > SHR_CONST_TKFRZ-3._r8 .and. &
              t_a5min > SHR_CONST_TKFRZ-3._r8 .and. ws_flag==1.0_r8 .and. &
              dayl>min_critical_daylength_onset*0.75_r8 .and. snow_5day<2._r8*snow5d_thresh_for_onset) then
         do_onset = .true.
      end if

  Note, this is likely to change phenology globally, and likely not in good ways.

See discussion in https://github.com/NCAR/LMWG_dev/discussions/3 AD spunup to 2.89% disequilibrium, 240 years pAD spunup to 5.86% disequilibrium, 440 years Complete

[olyson]

I'll work on this when I'm back on Tues.

[wwieder]

Thanks @olyson. There are 4 new cases for #3, as well as 4 new cases for #23. I think the dead vegetation issue is likely more important to prioritize, and setting up all the datm cases may be a bit more time consuming. I'll let you and @slevis-lmwg decide what makes the most sense for running and post processing all of these simulations. I appreciate your help!

[slevis-lmwg]

I'll work on this when I'm back on Tues.

@olyson I'm starting on this one now and let's see how far I get with @wwieder's requests today. Let's discuss division of the work on Tues. (or Weds at our meeting).

[slevis-lmwg]

Looking in /glade/scratch/oleson/archive, I see that you may have already started several of these, so I will wait.

[olyson]

Yes, #15, #16, #17, #22 have been started.

[olyson]