Deglaciation with bathymetry changes

1. Bathy

Things to modify

2.1. With new bathymetry

1) Modify / check choixcomposantes.h in scenario (scenario/deglaciation_pmip4_P_T/sources-2tr or scenario/deglaciation_pmip4_P_T/sources-17tr):

BATHY 2 
F_PALAEO 3 
ISM 3 
SMB_TYP 1 
CPLTYP 1 
DOWNSTS 1 
DOWNSCALING 1
LGMSWITCH 0 

Note: to have uncorrected FWF from ice sheets on top (not to be done in equilibrirum runs, only transient, otherwise issue with salinity computation):

APPLY_UNCORFWF 1
F_PALAEO_FWF 1 

Note 2: to have corrected FWF from ice sheets on top:

APPLY_UNCORFWF 0
F_PALAEO_FWF 1

2) Specifify the date in ludus-code/ecbilt/parameters/palaeo_transient_parameters.dat (see LGM section earlier).

3) Choose the correct ice sheet reconstruction for topography in ludus-code/ecbilt/inputdata/

• For Peltier: ICE6G_26k-0k_hemin40_Aurelien.nc:
  

ln -s ICE6G_26k-0k_hemin40_Aurelien.nc Gano_40k-0k_hemin40.nc
This file has 105 time slices, with a time step of 250 years, the first time slice is 26k and the last one is 0.

• For Tarasov: GLAC1D_26k-0k_hemin40_Aurelien.nc

ln -s GLAC1D_26k-0k_hemin40_Aurelien.nc Gano_40k-0k_hemin40.nc
This file has 261 time slices, with a time step of 100 years, the first time slice is 26k and the last one is 0.

You will also need to modify in palaeo_timer_mod.f90 and input_subgrid2L.f90 the values of :

• nb_steps_fism
• update_time_fism
• time_max_fism

4) In ludus-code/lbm/sources/routageEAU.f90: bricole_caspienne=.FALSE.

5) Change the path for GRISLI: in config/grisli.path change the line for:
/home/acclimate/aquiquet/GRISLI/GRISLI_iLoveclim

6) Specify inputdata, sources and restart (here starting from LGM):
Options to run the simulation with the correct scenarios:

• With two tracers:
  

./bin/loveclim-new-run -l PI-bathy -n 10 -r 10 -k -z -I scenario/deglaciation_pmip4_P_T/inputdata_peltier -F scenario/deglaciation_pmip4_P_T/sources-2tr -P scenario/deglaciation_pmip4_P_T/parameters-2tr -s 97801 -S /home/acclimate/nbouttes/iloveclim_degla/data/bathy_P_21000yr_2_CC_FWF_17tr2_ecbilt_clio/ic097801 -v 1

• Or with 17 tracers (Carbon cycle CC):
  

./bin/loveclim-new-run -l PI-CC-bathy -n 10 -r 10 -k -z -I scenario/deglaciation_pmip4_P_T/inputdata_peltier -F scenario/deglaciation_pmip4_P_T/sources-17tr -P scenario/deglaciation_pmip4_P_T/parameters-17tr -s 97801 -S /home/acclimate/nbouttes/iloveclim_degla/data/bathy_P_21000yr_2_CC_FWF_17tr2_ecbilt_clio/ic097801 -v 1

Restart from PI: -s 92801 -S /home/acclimate/flhardy/iloveclim/data/PI_20tr_t1.1_0.997_1.15_1.05_1.027_r25_ecbilt_clio/ic092801

Note :
specify correct update_time_fism in input_subgrid2L.f90 (500 for Peltier, 100 for Tarasov)

Note 2: for salinity

• If no FWF from ice sheets: the global salt mass is conserverd when bathymetry is changed, which modifies the global mean salinity
  
• If FWF from ice sheet: the global mean salinity is changed by the fresh water flux from ice sheets, while the global mean salinity is conserved when the bathymetry is changed.

2.1. changes uwing the berg.nc option (all ice sheets, north and south)

If you want to use berg.nc instead of berg.dat and icemask.nc (for ice sheets also in SO):

• modify flag in /ecbilt_clio/global_flags/BC_switches.h
  

#define NC_BERG 2

#define NC_IMSK 2

• in choixcomposantes.h:

#define BATHY 2

#define F_PALAEO 2

#define ISM 0

#define SMB_TYP 0

#define CPLTYP 0

#define DOWNSTS 0

#define DOWNSCALING 0

#define LGMSWITCH 0

• and specify inputdata with a directory in which you have the berg and icemask files

example:

starting from LGM with carbon cycle 17 tracers
./bin/run-iloveclim -l degla-CC -n 10 -r 10 -k -z -v 1 -I scenario/deglaciation_pmip4_P_T/inputdata_peltier -F scenario/deglaciation_pmip4_P_T/sources-13tr_SH -P scenario/deglaciation_pmip4_P_T/parameters-13tr -s 102801 -S /home/acclimate/nbouttes/iloveclim_degla2/data/bathy_P_21000yr_3b_SH_ecbilt_clio/ic102801