Nudging E004 Experiments


Title:    Miscellaneous Nudging Experiments


Synopsis:

There are often questions about nudging functionality, results, or requests for specific nudging experiments from colleagues. The E004 series is for carrying our experiments to address those needs.


Model Configuration:

Nudging utilizes YOTC data which has been interpolated to the prescribed 30 vertical levels with horizontal resolution ne30. The YOTC data covers the time period from May 1, 2009 thru April 30 2010.

The model is initialized with the YOTC data on May 1 2008 at 00Z.

Model Resolution: ne30 / L30
Model Tag: cesm1_3_beta06
Starting Date: 5 / 1 / 2008
Length of Runs: Up to 24 months.
user_nl_cam
(Startup / Outputs)
&cam_inparm
 fincl1='TAUTMSX','TAUTMSY','TAUGWX','TAUGWY','Nudge_U:A','Nudge_V:A','Nudge_T:A','Nudge_Q:A'
 fincl2='U:I','V:I','T:I','Q:I','OMEGA:I','PS:I','TAUTMSX:A','TAUTMSY:A','TAUGWX:A','TAUGWY:A',
             'Nudge_U:A','Nudge_V:A','Nudge_T:A','Nudge_Q:A'
 fincl3='PRECC:A','PRECL:A','FLNT:A','TMQ:A','LWCF:A'
 nhtfrq=0,-6,-3
 mfilt =1,4,8
 
 ncdata='/glade/scratch/patc/inputdata/nudging/YOTC_ne30np4_005/YOTC_ne30np4_L30.cam2.i.2008-05-01-00000.nc'
/
user_nl_cam

FAMIPC5 runs thru 2012 require extended versions of some input files

&prescribed_ozone_nl
  prescribed_ozone_datapath = '/glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/atm/cam/ozone'
  prescribed_ozone_file     = 'ozone_1.9x2.5_L26_1850-2015_rcp45_c101108.nc'
/

&prescribed_volcaero_nl
 prescribed_volcaero_datapath = '/glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/atm/cam/volc'
  prescribed_volcaero_file    = 'CCSM4_volcanic_1850-2011_prototype1.nc'
/

&chem_surfvals_nl
  bndtvghg  = '/glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/atm/cam/ggas/ghg_rcp45_1765-2500_c100405.nc'
/

&chem_inparm
 tracer_cnst_datapath           = '/glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/atm/cam/chem/trop_mozart_aero/oxid'
 tracer_cnst_file               = 'oxid_1.9x2.5_L26_1850-2015_rcp45_c101108.nc'
 ext_frc_specifier              = 'SO2         -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_so2_elev_1850-2020_c20120308.nc',
  'bc_a1       -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_bc_elev_1850-2020_c20120308.nc',
  'num_a1      -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_num_a1_elev_1850-2020_c20120308.nc',
  'num_a2      -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_num_a2_elev_1850-2020_c20120308.nc',
  'pom_a1      -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_oc_elev_1850-2020_c20120308.nc',
  'so4_a1      -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_so4_a1_elev_1850-2020_c20120308.nc',
  'so4_a2      -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_so4_a2_elev_1850-2020_c20120308.nc'
 srf_emis_specifier             = 'DMS       -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/aerocom_mam3_dms_surf_1849-2100_c111017.nc',
  'SO2       -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_so2_surf_1850-2020_c20120308.nc',
  'SOAG      -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_soag_1.5_surf_1850-2020_c20120308.nc',
  'bc_a1     -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_bc_surf_1850-2020_c20120308.nc',
  'num_a1    -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_num_a1_surf_1850-2020_c20120308.nc',
  'num_a2    -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_num_a2_surf_1850-2020_c20120308.nc',
  'pom_a1    -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_oc_surf_1850-2020_c20120308.nc',
  'so4_a1    -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_so4_a1_surf_1850-2020_c20120308.nc',
  'so4_a2    -> /glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/camdata/aero_1850-2100-RCP45/RCP45_mam3_so4_a2_surf_1850-2020_c20120308.nc'
/

&solar_inparm
  solar_data_file  = '/glade/p/work/patc/cesm1_1_0_rel06/inputdata30yr/atm/cam/solar/spectral_irradiance_Lean_1610-2140_ann_c100408.nc'
/

Experiment Configurations: Namelist Parameters
Control Run:

Nudging Active but all
coefficients set equal to 0.0
&nudging_nl
  Nudge_Model        =.true.
  Nudge_Path         ='/glade/scratch/patc/inputdata/nudging/YOTC_ne30np4_005/'
  Nudge_File_Template='YOTC_ne30np4_L30.cam2.i.%y-%m-%d-%s.nc'
  Nudge_Force_Opt=0
  Nudge_Diag_Opt =0
  Nudge_Times_Per_Day=4
  Model_Times_Per_Day=48
  Nudge_Uprof  =0
  Nudge_Ucoef  =0.0
  Nudge_Vprof  =0
  Nudge_Vcoef  =0.0
  Nudge_Tprof  =0
  Nudge_Tcoef  =0.0
  Nudge_Qprof  =0
  Nudge_Qcoef  =0.0
  Nudge_PSprof =0
  Nudge_PScoef =0.00
  Nudge_Beg_Year =2008
  Nudge_Beg_Month=5
  Nudge_Beg_Day  =1
  Nudge_End_Year =2100
  Nudge_End_Month=9
  Nudge_End_Day  =30
/
Nudged Runs:

STRENGTH = [0. - 1.]
&nudging_nl
  Nudge_Model        =.true.
  Nudge_Path         ='/glade/scratch/patc/inputdata/nudging/YOTC_ne30np4_005/'
  Nudge_File_Template='YOTC_ne30np4_L30.cam2.i.%y-%m-%d-%s.nc'
  Nudge_Force_Opt=0
  Nudge_Diag_Opt =0
  Nudge_Times_Per_Day=4
  Model_Times_Per_Day=48
  Nudge_Uprof  =1
  Nudge_Ucoef  =STRENGTH
  Nudge_Vprof  =1
  Nudge_Vcoef  =STRENGTH
  Nudge_Tprof  =1
  Nudge_Tcoef  =STRENGTH
  Nudge_Qprof  =2
  Nudge_Qcoef  =STRENGTH
  Nudge_PSprof =0
  Nudge_PScoef =0.00
  Nudge_Beg_Year =2008
  Nudge_Beg_Month=5
  Nudge_Beg_Day  =1
  Nudge_End_Year =2100
  Nudge_End_Month=9
  Nudge_End_Day  =30
  Nudge_Hwin_lo      =0.0
  Nudge_Hwin_hi      =1.0
  Nudge_Hwin_lat0    =0.0
  Nudge_Hwin_latWidth=9999.
  Nudge_Hwin_latDelta=1.
  Nudge_Hwin_lon0    =180.
  Nudge_Hwin_lonWidth=9999.
  Nudge_Hwin_lonDelta=1.
  Nudge_Vwin_lo      =1.0
  Nudge_Vwin_hi      =0.0
  Nudge_Vwin_Hindex  =29.5
  Nudge_Vwin_Hdelta  =0.001
  Nudge_Vwin_Lindex  =00.0
  Nudge_Vwin_Ldelta  =0.001
/



(1) Experiments with Different CO2 Concentration:

Two month experiments using {U,V,T,Qs}=1.0 (DEFAULT) nudging were carried out to test the effect of doubling the CO2 concentration in the atmosphere.

Experiment CO2 Settings Run Name Nickname
1X CO2
Default
f.e13b6.FAMIPC5.ne30_ne30.NudgeV2_E004.001
E004.001
2X CO2
CO2_PPMV = 0.000002
(no effect!)
f.e13b6.FAMIPC5.ne30_ne30.NudgeV2_E004.002
E004.002
2X CO2
CO2_PPMV = 0.000002
and
Modify file GHG_RCP45
with 2X CO2 values
f.e13b6.FAMIPC5.ne30_ne30.NudgeV2_E004.003 E004.003

The test E002.002 gave a null result since for FAMIP runs the value of CO2 is read in from the file 'ghg_rcp45_1765-2500_c100405.nc'.

The valid 2X CO2 test is E004.003 which uses the file 'ghg_rcp45_1765-2500_dbleCO2.nc', in which the CO2 contents of the original file are doubled.

The results and differences of the outgoing long-wave radiation at the top of the atmosphere (FLNT) for the two months are contained in the following table.


Default CO2
Double CO2
Difference
Default CO2 May 2008
2X CO2 May 2008
2X - Default CO2 May 2008
Default CO2 June 2008
2X CO2 June 2008
2X - Default CO2 June 2008

The following table contains profiles of the net cooling rates (QRL) averaged over latitude 30S-30N and their difference for the each month.


May 2008
June 2008
Profile May 2008
Profile June 2008

The monthly average (h0) output files for E004.001 and E004.003 are available for download:
 
  E004.001 (default CO2) : May 2008   June 2008
  E004.003 (double CO2) :  May 2008   June 2008

If desired, the other outputs from the h1/h2 files as indicated above are also available.





(2) Experiments: Effect of Nudging Placement on Precipitation:

Three month experiments using {UVTQs}=1.0 (DEFAULT) nudging in which the nudging tendencies are added at different points in the physics package. The current default usage has the nudging tendencies added at the very end of the tphysac() routine, after all physics parameterizations have been applied. The following outline indicates the placement of the nudging tendencies for each experiment.


routine TPHYSBC()
* Initialization Section
<==[E004.011]  BEGINNING OF THPYHSBC
* Global Energy Fixer
* Dry Adjustment
* Deep Convection
<==[E004.012]   AFTER DEEP CONVECTION
* Shallow Convection
* Re-bin Sea Salt / CARMA tendencies
<==[E004.013]  AFTER SHALLOW CONVECTION
* Macro/Micro physics
* Scavenging
<==[E004.014]  AFTER MICRO/MACROPHYSICS
* Radiation Computations
end routine TPHYSBC()

SURFACE COUPLING()

routine TPHYSAC()
* Initialization Section
<==[E004.015]  BEGINNING OF TPHYSAC
* Source/Sink Advected Tracers
* Vertical Diffusion / PBL Calculation
* Rayleigh Friction
* Aerosol Deposition
* Gravity Wave Drag
* Ion Drag
<==[E004.010]  END OF TPHYSAC  [DEFAULT]
end routine TPHYSAC()




Nudging Placement Experiment Run Name Nickname
END OF TPHYSAC  [DEFAULT] f.e13b6.FAMIPC5.ne30_ne30.NudgeV2_E004.010 E004.010
BEGINNING OF THPYHSBC f.e13b6.FAMIPC5.ne30_ne30.NudgeV2_E004.011 E004.011
AFTER DEEP CONVECTION f.e13b6.FAMIPC5.ne30_ne30.NudgeV2_E004.012 E004.012
AFTER SHALLOW CONVECTION f.e13b6.FAMIPC5.ne30_ne30.NudgeV2_E004.013 E004.013
AFTER MICRO/MACROPHYSICS f.e13b6.FAMIPC5.ne30_ne30.NudgeV2_E004.014 E004.014
BEGINNING OF TPHYSAC f.e13b6.FAMIPC5.ne30_ne30.NudgeV2_E004.015 E004.015


Results

The following table contains monthly average results for the last month of the 3-month tests. They indicate that the positioning of the nudging tendencies in the sequence of physics parameterizations has a relatively small effect on total precipitation.
 
July 2008 CAM Precipitation
Experiment
 Mean Map
Zonal Mean
Difference
Relative to E004.010
E004.010
END OF TPHYSAC


[N/A]
E004.011
BEGINNING OF THPYHSBC



E004.012
AFTER DEEP CONVECTION



E004.013
AFTER SHALLOW CONVECTION



E004.014
AFTER MICRO/MACROPHYSICS



E004.015
BEGINNING OF TPHYSAC