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(SOLVED)Wrong domains location in wrfout

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D

dengxw

New member
Dear Everyone,
I am using WRF3.9.1,and I find mistake in wrfout like this.
All domains have right value of XLAT and XLONG,but they can not get together well in wrfout.
There is my namlist.
Could someone help me?
Thank you in advance
Best regards,
Seaven
 

Attachments

  • namelist.input
    4.9 KB · Views: 32
  • namelist.wps
    1.6 KB · Views: 41
  • XLATinwrfout.png
    XLATinwrfout.png
    21.1 KB · Views: 1,115
The picture I sented before is XLAT in my wrfoutd01 showed by ncview.
We can see different rectangulars of different domains. In general ,they should fit together so that we're just going to see one rectangle .
I think it means the positions of the different domains do not correspond exactly.
I am attaching HGT in my wrfoutd03 in order to clarify my question more clearly. The places circled in red have same positions, but they are showed twice.
All vars of my wrfout are like that. They have right value, but they diverged when they merged in wrfout.
I don't know if I'm making myself clear.
Thank you.
 

Attachments

  • HGTind03.JPG
    HGTind03.JPG
    80.6 KB · Views: 1,112
I guess I understand your question. This is attributed to the wrong settings of your model domain. In your namelist.wps, you have the nest domains setting by:
Code: 
 parent_id         =   1,   1,   1,   1,
 parent_grid_ratio =   1,   3,   9,   27,
 i_parent_start    =   1,  31,   45,  53,
 j_parent_start    =   1,  30,   43,  53,
 e_we              =  112, 169,  226, 190,
 e_sn              =  112, 169,  226, 217,

Note that the nesting grid ratio shouldn't be too large. It is better 3 or 5. Your grid ratios of 9 and 27 are way too large.
Also, the child domains shouldn't overlap. In your case, all the child domains overlap more or less. Somehow the model will be confused by such settings and result in weird output.
Please modify namelist.wps and specify reasonable options for domain settings.
 
I understand what you tried to do, but it's the wrong way.
Your nesting should be like this:
Code: 
 parent_id         =   1,   1,   2,  3,
 parent_grid_ratio =   1,   3,   3,   3,

Then check the position respect the parent domain.
An useful tool to define your domain is GIS4WRF in QGIS, you start from the highest resolution domain to the lower one. https://gis4wrf.github.io
 
@dengxw
Are you trying to set up a case with multiple nesting domains? For example, D01 is the parent domain of D02, and D02 is the parent domain of D03, etc.?
 
cross85 said:
I understand what you tried to do, but it's the wrong way.
Your nesting should be like this:
Code: 
 parent_id         =   1,   1,   2,  3,
 parent_grid_ratio =   1,   3,   3,   3,

Then check the position respect the parent domain.
An useful tool to define your domain is GIS4WRF in QGIS, you start from the highest resolution domain to the lower one. https://gis4wrf.github.io
Click to expand...
@cross85
Thank you for your adivce, I notice that I had given wrong parent domain settings to wrf.
I took your advice and revised my namelist.wps and namelist.input correspondingly.
My domains overlap very well.
Thank you so much!
 
Ming Chen said:
@dengxw
Are you trying to set up a case with multiple nesting domains? For example, D01 is the parent domain of D02, and D02 is the parent domain of D03, etc.?
Click to expand...

Yes, I am trying to set up a case with multiple nesting domains.
I took cross85's advice and revised my namelist, but the position did not change.
Then I set up a case with
Code: 
 grid_id           =   1,   2,  3,
 parent_id         =   1,   1,  2,
 parent_grid_ratio =   1,   5,   5,   
 i_parent_start    =   1,  42,  53,
 j_parent_start    =   1,  42,  53,
 e_we              =  112, 146, 176,
 e_sn              =  112, 146, 201,
The displacement is smaller then before, but it still exists.
 

Attachments

  • xlat-in-d02.JPG
    xlat-in-d02.JPG
    32.9 KB · Views: 1,093
cross85 said:
I understand what you tried to do, but it's the wrong way.
Your nesting should be like this:
Code: 
 parent_id         =   1,   1,   2,  3,
 parent_grid_ratio =   1,   3,   3,   3,

Then check the position respect the parent domain.
An useful tool to define your domain is GIS4WRF in QGIS, you start from the highest resolution domain to the lower one. https://gis4wrf.github.io
Click to expand...
I am so sorry.
I just noticed that I only changed namelist.input.I did not change namelist.wps.
Then I revised my namelist.wps and namelist.input correspondingly.
My domains overlap very well.
Thank you so much!
 
Ming Chen said:
Please upload your full namelist.wps for me to take a look. Thanks.
Click to expand...

I am so sorry for my oversight.
Thank you for reminding me that I only changed namelist.input.
I did not change namelist.wps correspondingly
Then I revised my namelist.wps and namelist.input correspondingly.
My domains overlap very well.
Thank you so much!
 
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