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Can I perturb the "climatology" with a specific volcanic eruption?

L

linlin

New Member
Hi,

I wonder if it is possible to investigate the impacts of volcanic eruption under a typical climatology background.

I guess I might run FW2000climo. In the user_nl_cam, I will replace 'SO2 -> /glade/p/cesmdata/cseg/inputdata/atm/cam/chem/stratvolc/VolcanEESMv3.10_SO2_1995-2005average_1deg_ZeroTrop_c180912.nc' with 'SO2 -> /glade/p/cesmdata/cseg/inputdata/atm/cam/chem/stratvolc/VolcanEESMv3.11_SO2_850-2016_Mscale_Zreduc_1deg_c191121.nc'; keep the remaining ext_frc_specis the same as default in FW2000climo; setting ext_frc_cycle_yr = 0; setting ext_frc_type = 'INTERP_MISSING_MONTHS'. Also set run_startdate=2015-02-01 for example.

Best,
Lin
 
mmills

mmills

CSEG and Liaisons
Staff member
Sure, you can do that. You just need to change your RUN_STARTDATE to be at the beginning of a year with an eruption or eruptions that you would like to simulate.

You should know that the F compsets use specified sea surface temperatures, so you will not see the true impacts of eruptions on the surface climate. If you are interested in effects on stratospheric temperatures and ozone, however, this is a reasonable approach.
 
L

linlin

New Member
mmills said:
Sure, you can do that. You just need to change your RUN_STARTDATE to be at the beginning of a year with an eruption or eruptions that you would like to simulate.

You should know that the F compsets use specified sea surface temperatures, so you will not see the true impacts of eruptions on the surface climate. If you are interested in effects on stratospheric temperatures and ozone, however, this is a reasonable approach.
Click to expand...

Thanks a lot Mike.

I changed my RUN_STARTDATE to be at the beginning of a year, say 2015-01-01, the model still crashed as I set RUN_STARTDATE=2015-02-01.

The error message is quoted below:

READ_NEXT_TRCDATA emiss_res_tran
FIND_TIMES: Failed to find dates bracketing desired time =
0.000000000000000E+000
filename = /glade/p/cesmdata/cseg/inputdata/atm/cam/chem/emis/CMIP6_emissions_2
000climo/emissions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c20170322.nc
datatimem = -5156.00000000000
datatimep = -5126.00000000000
incr_flnm: old filename =
/glade/p/cesmdata/cseg/inputdata/atm/cam/chem/emis/CMIP6_emissions_2000climo/em
issions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c20170322.nc
incr_flnm: new filename =
/glade/p/cesmdata/cseg/inputdata/atm/cam/chem/emis/CMIP6_emissions_2000climo/em
issions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c20170323.nc
(GETFIL): attempting to find local file
emissions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c20170323.nc
(GETFIL): all tries to get file have been unsuccessful:
/glade/p/cesmdata/cseg/inputdata/atm/cam/chem/emis/CMIP6_emissions_2000climo/em
issions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c20170323.nc
ERROR:
GETFIL: FAILED to get /glade/p/cesmdata/cseg/inputdata/atm/cam/chem/emis/CMIP6_
emissions_2000climo/emissions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c2
0170323.nc

I just don't know why the model cannot read the correct NO2 2000climo file.
And this error might be associated with the setting combinations in RUN_STARTDATE, $chem_inparm...

for your reference, (1) I set RUN_STARTDATE=2015-01-01; (2) ext_frc_cycle_yr = 0; (3) ext_frc_type = 'INTERP_MISSING_MONTHS'; (4) use 'SO2 -> /glade/p/cesmdata/cseg/inputdata/atm/cam/chem/stratvolc/VolcanEESMv3.11_SO2_850-2016_Mscale_Zreduc_1deg_c191121.nc', keeping everything else in ext_frc_specifier the same as default.

Best,
Lin
 
mmills

mmills

CSEG and Liaisons
Staff member
linlin said:
Thanks a lot Mike.

I changed my RUN_STARTDATE to be at the beginning of a year, say 2015-01-01, the model still crashed as I set RUN_STARTDATE=2015-02-01.

The error message is quoted below:

READ_NEXT_TRCDATA emiss_res_tran
FIND_TIMES: Failed to find dates bracketing desired time =
0.000000000000000E+000
filename = /glade/p/cesmdata/cseg/inputdata/atm/cam/chem/emis/CMIP6_emissions_2
000climo/emissions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c20170322.nc
datatimem = -5156.00000000000
datatimep = -5126.00000000000
incr_flnm: old filename =
/glade/p/cesmdata/cseg/inputdata/atm/cam/chem/emis/CMIP6_emissions_2000climo/em
issions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c20170322.nc
incr_flnm: new filename =
/glade/p/cesmdata/cseg/inputdata/atm/cam/chem/emis/CMIP6_emissions_2000climo/em
issions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c20170323.nc
(GETFIL): attempting to find local file
emissions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c20170323.nc
(GETFIL): all tries to get file have been unsuccessful:
/glade/p/cesmdata/cseg/inputdata/atm/cam/chem/emis/CMIP6_emissions_2000climo/em
issions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c20170323.nc
ERROR:
GETFIL: FAILED to get /glade/p/cesmdata/cseg/inputdata/atm/cam/chem/emis/CMIP6_
emissions_2000climo/emissions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c2
0170323.nc

I just don't know why the model cannot read the correct NO2 2000climo file.
And this error might be associated with the setting combinations in RUN_STARTDATE, $chem_inparm...

for your reference, (1) I set RUN_STARTDATE=2015-01-01; (2) ext_frc_cycle_yr = 0; (3) ext_frc_type = 'INTERP_MISSING_MONTHS'; (4) use 'SO2 -> /glade/p/cesmdata/cseg/inputdata/atm/cam/chem/stratvolc/VolcanEESMv3.11_SO2_850-2016_Mscale_Zreduc_1deg_c191121.nc', keeping everything else in ext_frc_specifier the same as default.

Best,
Lin
Click to expand...
Okay, I understand why you are having a problem. For the FW2000 compset, the following defaults need to be maintained to use the original emissions files:
ext_frc_cycle_yr = 2000
ext_frc_type = 'CYCLICAL'

This is because the dates in the original emissions files are all for year 2000. For example:

ncdump -v date /glade/p/cesmdata/cseg/inputdata/atm/cam/chem/emis/CMIP6_emissions_2000climo/emissions-cmip6_NO2_aircraft_vertical_2000climo_0.9x1.25_c20170322.nc

date = 20000116, 20000216, 20000316, 20000416, 20000516, 20000616, 20000716, 20000816, 20000916, 20001016, 20001116, 20001216 ;

The volcanic SO2 emission file from the transient compsets does have an attribute that forces it to be read in as SERIAL times when ext_frc_type = 'INTERP_MISSING_MONTHS' for other emissions files in the transient compset.

ncdump -h /glade/p/cesmdata/cseg/inputdata/atm/cam/chem/stratvolc/VolcanEESMv3.11_SO2_850-2016_Mscale_Zreduc_1deg_c191121.nc | grep SERIAL

:input_method = "SERIAL"

However, I think that this will fail when ext_frc_type = 'CYCLICAL'. Instead, you are likely to get volcanic emissions for the year 2000 regardless of your RUN_STARTDATE. I am not sure if this has been fixed.

I believe there was a workaround created for DAMIP simulations, in which additional seasonal cycles were added to emissions files so that they could be held constant at pre-industrial values when ext_frc_type = 'INTERP_MISSING_MONTHS'. You can do something similar by creating new versions of all of the emissions files in which you add seasonal cycles for a year well before the start of all your runs start, and another well after all of your runs end.

I will ask a few others to see if anyone knows whether the files you need have been created already.
 
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