Hi, everyone. I want to start a simulation on 2012 with EQUATESv1.0 data. The region I want to do simulation is the southeast region which looks like in the image. I need to prepare my own meteorology file from wrf so I need a namelist.wps which can use EQUATESv1.0 grid. I have calculate that the xorig and yorig should be 120000 and -1548000 for me. How to convert it to namelist.wps.
If you just want to run the SE part of the 12US1 CONUS EQUATES grid, it is simpler to pick a part of that grid that covers the SE US and then take what the MCIP calcs provide as xorig and yorig. I nor anyone in our WRF modeling group does it the way you describe above.
I can help with a sample namelist a bit later this afternoon.
Do you mean that I should use the ready MCIP file and pick a gridname which include the part I want? I have run in that way before for mid area. Because I cannot find the grid name I want last time.
Actually, it seems that I do not know how to do the simpler way.
Working on an example right now. You can start with the 12US1 namelist.wps and add a 12 km nested grid that will lie on top of the CONUS grid. Then use this nested 12 km as your new WRF grid by creating a namelist.wps for that nested config. Give me an hour and Iāll have an example.
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Thank you. Last time, I didnāt do a nested domain but it maybe a good luck.
Example namelist sections and steps below.
- run geogrid for 12US1 namelist.wps that has a nested 12 km domain over the SE US. Note that you will have to interated perhaps if you donāt like the nested 12 km domain I roughly set in the namelist. This can be done by modifying the I, j parent start of this nest within the 12US1 CONUS. And the number of grid cells that I have set to 175x175. This example does cover the map area of the SE US you have in the post.
&geogrid
parent_id = 1, 1,
parent_grid_ratio = 1, 1,
i_parent_start = 1, 230,
j_parent_start = 1, 10,
s_we = 1, 1,
e_we = 472, 175,
e_sn = 312, 175,
s_sn = 1, 1,
geog_data_res = āmodis_30s_lakeā,āmodis_30s_lakeā,
dx = 12000,
dy = 12000,
map_proj = ālambertā,
ref_lat = 40,
ref_lon = -97,
ref_x = 219.5,
ref_y = 150.5,
truelat1 = 33,
truelat2 = 45,
stand_lon = -97.0,
geog_data_path = ā/work/MOD3DATA/WRF/WPS_GEOGā
opt_geogrid_tbl_path = ā/home/rgilliam/WRF/WPS-4.5/geogridā
/
-
You will get a geo_em.d01.nc geo_em.d02.nc for the CONUS12 and nested 12 km domain. Run a ncdump -h geo_em.d02.nc. Take the center lat and lon of this nest from the ncdump.
:CEN_LAT = 33.41792f ; :CEN_LON = -84.4072f ; -
Create a single domain namelist.wps for this domain. Use the center lat-lon of the nest domain here as the center of this new domain. You do not need the ref_x and ref_y like the above namelist because itās assumed by default that this is the center of the domain. New single domain namelist grid settings below. The lambert projection settings are the same so it will lay on top of the CONUS12 grid, but the domain is smaller and centered in a different location.
&geogrid
parent_id = 1,
parent_grid_ratio = 1,
i_parent_start = 1,
j_parent_start = 1,
s_we = 1,
e_we = 175,
e_sn = 175,
s_sn = 1,
geog_data_res = āmodis_30s_lakeā,
dx = 12000,
dy = 12000,
map_proj = ālambertā,
ref_lat = 33.41792,
ref_lon = -84.4072,
truelat1 = 33,
truelat2 = 45,
stand_lon = -97.0,
geog_data_path = ā/work/MOD3DATA/WRF/WPS_GEOGā
opt_geogrid_tbl_path = ā/home/rgilliam/WRF/WPS-4.5/geogridā
/
-
Rerun geogrid.exe for this new domain and you now have a single domain nested in this CONUS12. And of course other preprocessing for WRF. And then WRF.
-
Once you run WRF and have an output and run MCIP, you will have the domain information in āMCIPā coordinates. You can use emissions and all sorts of other CMAQ files by windowing to this domain.
Best of luck.
Rob
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Thank you so much. Can you explain to me how to do that and I can do it next time by myself
Youāre welcome. Best of luck with the steps outline above.
Hi, I have one question that why you know 175 175 will work here