how to change the O3 forcing in the CTSM BGC-crop model

[jinmuluo]

Describe your problem or question:
Hi,
I want to change the prescribed O3 concentration used in the crop model when turning on the ozone damage function. I found that CLM provides 'DATM_PRESO3' option in the env_run.xml, and defines the stream of ozone in CaseDocs/datm.streams.xml. So my question is how to change this information in the user_nl_clm, like the stream start year, dataset input, and the cycle method?

Thank you


<stream_info name="preso3.clim_2000">
<taxmode>cycle</taxmode>
<tintalgo>linear</tintalgo>
<readmode>single</readmode>
<mapalgo>bilinear</mapalgo>
<dtlimit>1.5</dtlimit>
<year_first>2000</year_first>
<year_last>2000</year_last>
<year_align>1</year_align>
<vectors>null</vectors>
<meshfile>/glade/campaign/cesm/cesmdata/inputdata/share/meshes/fv0.9x1.25_141008_polemod_ESMFmesh.nc</meshfile>
<lev_dimname>null</lev_dimname>
<datafiles>
<file>/glade/campaign/cesm/cesmdata/inputdata/cdeps/datm/ozone/O3_surface.f09_g17.CMIP6-historical-WACCM.001.monthly.185001-201412.nc</file>
</datafiles>
<datavars>
<var>O3 Sa_o3</var>
</datavars>
<offset>0</offset>
</stream_info>

 

[slevis]

To change this, you do not modify user_nl_clm but user_nl_datm_streams, and you can see the outcome (before you change it and after) in an existing case in CaseDocs/datm.streams.xml

 

[jinmuluo]

To change this, you do not modify user_nl_clm but user_nl_datm_streams, and you can see the outcome (before you change it and after) in an existing case in CaseDocs/datm.streams.xml

Hi Sam,

So, I just need to edit and copy all of the namelist below into the user_nl_datm_streams?

<stream_info name="preso3.clim_2000">
<taxmode>cycle</taxmode>
<tintalgo>linear</tintalgo>
<readmode>single</readmode>
<mapalgo>bilinear</mapalgo>
<dtlimit>1.5</dtlimit>
<year_first>2020</year_first>
<year_last>2020</year_last>
<year_align>1</year_align>
<vectors>null</vectors>
<meshfile>/glade/campaign/cesm/cesmdata/inputdata/share/meshes/fv0.9x1.25_141008_polemod_ESMFmesh.nc</meshfile>
<lev_dimname>null</lev_dimname>
<datafiles>
<file>my.nc</file>
</datafiles>
<datavars>
<var>O3 Sa_o3</var>
</datavars>
<offset>0</offset>
</stream_info>

 

[slevis]

I have not tried this myself for ozone, but I am pretty sure that the answer is yes.

 

[jinmuluo]

I have not tried this myself for ozone, but I am pretty sure that the answer is yes.

Thank you, Sam.

and for anyone who wants to follow this thread, I found an easy way to do so in user_nl_datm_streams.
What we need to do is follow the way below to change the stream information

stream_info name:datafiles=YOUFILE

as I did in my user_nl_datm_streams

preso3.clim_2000:datafiles=XX.nc
preso3.clim_2000:year_first=2011
preso3.clim_2000:year_last=2011