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Mismatch topography and landmask

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Dear all,

I am about to setup a simulation over Antarctica using the WRF / WPS version 4.0.3. I plan to initialize and run WRF with ERA5 data (currently on pressure levels).

To run geogrid I use the following input data:
- topo_BedMap2_30s/
(GEOGRID.TBL attached)

My namelist.wps is the following:
wrf_core = 'ARW',
max_dom = 1,
start_date ='2017-03-01_00:00:00','2017-03-01_00:00:00','2017-03-01_00:00:00','2017-03-01_00:00:00','2017-04-05_00:00:00',
end_date ='2017-03-16_00:00:00','2017-03-02_00:00:00','2017-03-02_00:00:00','2017-03-02_00:00:00','2017-04-05_01:00:00',
interval_seconds = 21600,
io_form_geogrid = 2,
parent_id = 1,1,2,3,4,
parent_grid_ratio = 1,3,3,3,4,
i_parent_start = 1,115,160,100,157,
j_parent_start = 1,85,58,90,157,
e_we = 200,256,256,256,421,
e_sn = 200,256,256,256,421,

geog_data_res ='30sBM+30s','30sBM+30s','30sBM+30s','30sBM+30s','30sBM+30s',
dx = 27000,
dy = 27000,
map_proj = 'polar',
ref_lat = -90.0,
ref_lon = 0.0,
truelat1 = -65.0,
! les deux suivants ne servent pas en projection polaire
! truelat2 = 60.0,
stand_lon = 0.0,
geog_data_path = '/scratch/snx3000/gerberf/Antarctica/WRF_INPUT_DATA/GEOG_DATA/',

out_format = 'WPS',
prefix = 'FILE',

!constants_name = 'FIX:2016-01-01_00',
fg_name = 'FILE',
io_form_metgrid = 2,

I attach a figure showing the mismatch between topography and the landmask (one figure shows the whole domain d01, the other figure shows a zoomed in figure showing a certain part of the coast). Is this a known problem? Did I miss any adaptations needed in my GEOGRID.TBL or namelist file?

I will be happy to provide additional information.
Thank you in advance and best regards,


  • Antarctica_topo_landmask-zoomed.png
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  • Antarctica_topo_landmask.png
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Hi Franziska,

I first would like to apologize for the long delay in response to your question. It was certainly not our intent to overlook this post. Have you been able to get past this problem yet? If not, take a look at this post:

Perhaps the same problem is happening here with the default MODIS data. Can you try the 15s data to determine whether it corrects the problem?

Hi Kelly,

Thank you for your reply. Unfortunately, your suggestions didn't solve the problem. However, by now we created new topography tiles from the REMA digital elevation model and a corresponding landuse tile for which the problem doesn't exits anymore.

Thanks a lot and cheers,