Scheduled Downtime
On Tuesday 24 October 2023 @ 5pm MT the forums will be in read only mode in preparation for the downtime. On Wednesday 25 October 2023 @ 5am MT, this website will be down for maintenance and expected to return online later in the morning.
Normal Operations
The forums are back online with normal operations. If you notice any issues or errors related to the forums, please reach out to help@ucar.edu

sensitivity experiment about the circulation response to the anomalous soil moisture in the specific region

Cliff Chen

New Member
Hello all:
I was trying to modulate the response of the circulation to the anomalous soil moisture in a specific region in CAM6. I found that there is a variable (atm_in) that may contains the soil data (clim_soilw_file), so, I changed the prescribed soil moisture in it and ran two cases (Positive and Negative). However, the response of the circulation in the two cases are same, indicting no anomalous signals were added in. I also checked the (atm.log.xxxx) file, there is no sign that the cases invoking the (clim_soilw_file), despite is was written in the (atm_in).
I'm not sure the process I adopted is right, or anyone knows how to run such a sensitive experiment.
Thanks in advance~
 

slevis

Moderator
Staff member
@Cliff Chen I'm not familiar with the file that you mentioned. There may be a way to prescribe the soil moisture that I'm not aware of.

Otherwise though, the land model simulates soil moisture as explained in the clm technical note:
You would need to come up with a way to overwrite (or nudge or whatever you have in mind) the simulated soil moisture.
 

Cliff Chen

New Member

oleson

Keith Oleson
CSEG and Liaisons
Staff member

Cliff Chen

New Member
This post might be of help also:

Thanks very much for your reply! Oleson. It seems that I have solved the issue following the method. it will be confirmed after running more cases.
Sorry to disturb you, I came up with another question. I was wondering is there a file that contains the prescribed snow-covered fraction or any other variables about snow cover (As far as I understand, the variable SFC is used in the CLM according to the User's guide), so that, I can change the data in the specific month and region. Or, the SFC is just used in the initial field for the RUN_STARTDATE?
Thanks in advance!
 

slevis

Moderator
Staff member
There is no file containing prescribed snow-cover fraction and - off the top of my head - I do not recognize the variable name SFC that you mention.
 

Cliff Chen

New Member
There is no file containing prescribed snow-cover fraction and - off the top of my head - I do not recognize the variable name SFC that you mention.
Thanks very much for your reply! slevis. so, there is no prescribed variables about snow cover for the initial field which can only be got from the output data. Is that right?
 

oleson

Keith Oleson
CSEG and Liaisons
Staff member
I probably don't understand your question, but there are snow fields on the initial file that you use to start your simulation. The file is prescribed by finidat in your lnd_in. That just initializes the snowpack, after that, the model prognoses snow cover.
 

LiMa

Li Ma
New Member
I am a beginner and would like to run snow driven sensitivity experiments only in CAM mode, is this feasible? Must CLM be coupled? Is there a snow field in the initial file in CAM. Thank you
 
Top