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user/ctlod/ORCA2Runs/LIM2 – NEMO
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Sensitivity experiments performed with LIM 2.0


Abstract for the simulations performed over 10/500 or 1000 years (last ones are the first presented):

  • for PHC_40? based on tag nemo_v3_1 :
    - nn_sssr=2
    - alpha_precip=alpha_runoff=1. & no more +10% applied on evaporation
    - bug on sbcrnf.90 corrected
    

* for PHC_72? based on PHC_57 but :Color(white, red, ON GOING )?

- set nn_htau to 1 instead 2 in nemtke namelist, impact on the TKE penetration 

* for PHC_71? based on PHC_57 but :Color(white, red, ON GOING )?

- set nn_htau to 1 instead 2 in nemtke namelist, impact on the TKE penetration 

* for PHC_70? based on PHC_57 but :Color(white, red, ON GOING )?

- use EVP rheology instead VP one with LIM 2.0 

* for PHC_68? based on PHC_57 but :Color(white, red, ON GOING )?

- special treatment of Cdrag over ocean & ice, it depends on the ice thickness
  • for PHC_67? based on PHC_57 but :
    - decrease P* parameter to: 0.5e+4
    

  • for PHC_66? based on PHC_57 but :
    - increase P* parameter to: 2.e+4 
    
  • for PHC_65? based on PHC_57 but :
    - remove the sea-ice dynamics: ln_limdyn = .FALSE. 
    
  • for PHC_64? based on PHC_49 but :
    - based on the new World Ocean Data 2005, it's the only difference
    
  • for PHC_63? based on PHC_49 but :
    - remove the SSS restoring term, nn_sssr = 0
    
  • for PHC_62? based on PHC_49 but :
    - balance the erp term every nn_fwbc so it's mean is zero nn_fwb = 4
    
  • for PHC_61? based on PHC_49 but :
    - apply a correction of empold the first year, this experience is similar to PHC_56
    
  • for PHC_60? based on PHC_49 but :
    - reduce the runoffs by 15% beyond 60°N until North Pole
    
  • for PHC_59? based on PHC_49 but :
    - change straits topography around Denmark straits and North to Scotland
    
  • for PHC_58? based on PHC_49 but :
    - balance the emp term every nn_fwbc using the emp mean of the previous year,
    this time we use the true annual emp mean not the instantaneous one as in experience PHC_55 which was a mistake.
    

* for PHC_57? based on PHC_49 but :Color(white, red, ON GOING beyond 100 years (till 1000 years))?

- balance the emp term every nn_fwbc so it's mean is zero nn_fwb = 4 

* for PHC_56? based on PHC_49 but :Color(white, red, ON GOING beyond 100 years (till 1000 years))?

- correction of the empold of the previous year every nn_fsbc time step nn_fwb = 2
- this trend is redistributed only over erp(:,:) area of same sign
  • for PHC_54? based on PHC_49 but :
    - First 10 years performed in "robust diag" state, i.e. ndmp = 20, no damping in ML.
    the following 10 years are done in switching off this option
    
  • for PHC_50? based on PHC_49 but :
    - reduce the SSS damping erp term along coast over 400 km wide
    
  • for PHC_49? based on PHC_37 but :
    - set nn_fwb = 0
    - SSS damping term erp tapered to -4 or +4 mm/day in sbcssr.F90
    
  • for PHC_48? based on PHC_46 but :
    - set nn_fwb = 0 no more cvolume control
    
  • for PHC_47? based on PHC_45 but :
    - reduce precipitation & runoffs by a factor of 0.006
    
  • for PHC_46? based on PHC_37 but :
    - nn_fwb = 2, still volume control
    - increase linearly the SSS damping term from 0 at the coast to 1 at 400 km off coast
    - correct concentration/dilution term in Batltic Sea in limsbc_2.F90
    - add the Bering strait transport computation in diafwb.F90
    
  • for PHC_45? based on PHC_37 but :
    - nn_fwb = 0, i.e. no more volume control  
    
  • for PHC_44? based on PHC_37 but :
    - TKE penetration increased to 10% instead 5% && nn_fwb = 0, i.e. no more volume control  
    
  • for PHC_43? based on PHC_37 but :
    - damping term coefficient deds = -166mm/day instead -864mm/day 
    
  • for PHC_41? based on PHC_37 but :
    - tapering the damping term erp o -6 or 6 mm/day 
    

  • for PHC_42? based on PHC_16 but :
    - sea-ice albedo is set to 0.53 instead 0.50
    
  • for PHC_39? based on PHC_16 but :
    - Reduce the SSS damping parameter from 864mm/day to 166 mm/day
    
  • for PHC_38? based on PHC_16 but :
    - Remove the SSS damping under Sea-ice area using frld field in sbcssr.F90
    

  • for PHC_37? based on PHC_36 but :
    - set nn_sssr = 2 instead 1 to take into account concentration/dilution effect through emps array.
    
  • for PHC_36? based on PHC_35 but :
    - remove the -9% on precipitation & runoff and +10% on evaporation field since the bug on sbcrnf.F90 is corrected
    
  • for PHC_35? based on PHC_16 but :
    - bug correction in sbcrnf.F90 module concerning missing test MOD(kt-1,nn_fsbc).
    
  • for PHC_34? based on PHC_16 but :
    - set now nn_sssr = 2 instead 1 and correct bu into sbcssr.F90 using (nn_sssr >= 1) instead (nn_sssr == 1)
    
  • for PHC_32? based on PHC_16 but :
    - apply air temperature correction on DFS4 data between 65°S & 80°S following differences with CLIO data.
    - The PHC_33 experience has a lower correction on air temperature than PHC_32.
    
  • for PHC_31? based on PHC_16 but :
    - set minimum of leads (acrit variable) to 2% in both hemispheres in the sea-ice namelist instead default value of 1.1O^-6
    


  • for PHC_16? based on PHC_15 but :
    - apply -9% on precipitation & runoff instead of -8% in PHC_15 experiment
    
  • for PHC_15?: based on PHC_11 but :
    just use "good" input fields for K1 and M2 waves
    
  • for PHC_12 based on PHC_11 but :
    few tests to improve transport of few straits:
    - fmask = 4.0 at the output of the Baltic sea
    - fmask = 0.5 at Gibraltar
    - fmask = 1.0 at Bab El Mandeb & add an identical value at one corner of the strait
    - one specificity of the Sound strait is an annual mean output flow, so to catch it in outputs,
    few modifications have been done in the diafwb.F90 module. further more an error on the location
    of the Sound strait has been also corrected
    - 
    
  • for PHC_11: based on PHC_10 but includes both:
    it seems that input fields were not the good ones
    - global Kz tides 
    - increased Kz tides in the ITF area
    
  • for PHC_10?: based on PHC_9 but includes both:
    - 3 waves lenghts penetration (RGB) through the traqsr.F90 module 
    - ocean color: climatology of a 2D chlorophyll field
    
  • for PHC_9?: based on the PHC_8 experiment
    change the way to compute wind stress & wind module:
    - wind module is now read and corresponds to ||U||clim, i.e. the one computed using 6hourly components 
    not the one using climatological components Uclim/Vclim 
    - wind stress: (||U||.u)clim & (||U||.v)clim fields are directly read instead computed. the drag coefficient is the one 
    computed using on the wind module read just above.
    - in doing this we don't substract anymore relative velocity of the ocean/sea-ice in the computation of the wind module 
    and the wind stress
    
  • for PHC_4?: based on the PHC_3 experiment
    just remove the TKE penetration in setting nn_etau= 0 in namelist:
    
  • from PHC_1 to PHC_8 :
    all these runs have been used for:
    - freshwater budget adjustement in playing with new namelist parameters alpha_precip, alpha_runoff
    - Gibraltar, Bab El Mandeb & Sound sraits transports adjustement ( based on scale factors or/and bondary condition fmask )
    - they all used the following computation for the wind module:  we add the wind module variance difference 
    (||U||clim)^2 - (Uclim^2 + Vclim^2) to the computation of the wind module where ||U||clim is the climatological wind module 
    and Uclim/Vclim are the climatological wind component
    


Results from the 10th year:

Runs PHC_1 PHC_2 PHC_3 PHC_5 PHC_6 PHC_7 PHC_8 PHC_9 PHC_10 PHC_11 PHC_15 PHC_16
Precip / -10% -12% / -8% -10% -8% -8% -8% -8% -8% -9%
Evap / / / +10% +5% +10% +10% +10% +10% +10% +10% +10%
Empold (Sv) +1.88 +0.26 -0.06 +1.37 +0.31 -0.25 +0.07 +0.13 +0.1 +0.12 +0.13 -0.02
SST/rt PHC3 / / / ++ + ++ ++ ?? ?? ?? ?? ??
SSH drift (m) / / -0.006 +0.12 +0.028 -0.022 +0.006 +0.01 +0.008 +0.01 +0.01 -0.002


Last modified 15 years ago Last modified on 2009-06-04T16:15:20+02:00

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