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Wind is not captured properly by WRF (in COAWST) over the Arabian Sea

SPLahiri

New member
Hello everyone. I am facing some difficulties in simulating the actual wind over the Arabian Sea. I am using WRF (stand alone) in COAWST. I have run the model for 1 month. After some days the model is not capturing the wind direction properly. In my model the outer domain is whole Indian Ocean and the inner domain is Arabian Sea. Here I am attaching the input file and the results from inner domain. It will be very benefical if someone can help me out in this regard. Thanks in advance.
 

Attachments

  • ASCAT_WIND_15_26_MAY.png
    1.9 MB · Views: 5
  • ASCAT_WIND_3_14_MAY.png
    1.8 MB · Views: 3
  • WRF_WIND_15_26_MAY.png
    3.3 MB · Views: 1
  • WRF_WIND_3_14_MAY.png
    3.3 MB · Views: 1
  • namelist.input
    4.9 KB · Views: 6
Hi,
Can you let me know which version of WRF you are using to run this? I also notice you are using very coarse resolution (60km, 20km). Most input data is available at resolutions much higher than that. Is this limited because you'll be coupling it to the ocean with COAWST? If not, please let me know the resolution of your input data. I also notice your time_step is very low. Were you receiving CFL errors when using a higher value? The recommended value is 6xDX, unless you get CFL errors.
 
Hi,
Can you let me know which version of WRF you are using to run this? I also notice you are using very coarse resolution (60km, 20km). Most input data is available at resolutions much higher than that. Is this limited because you'll be coupling it to the ocean with COAWST? If not, please let me know the resolution of your input data. I also notice your time_step is very low. Were you receiving CFL errors when using a higher value? The recommended value is 6xDX, unless you get CFL errors.
Hi Kwerner. Thank you for your reply. I am incredibly sorry for replying this late. I am using WRF version 4.2.2. I want to couple it with ROMS, so I have kept the resolution low. The resolution of input data is 31 km ERA5 dataset. I haven't checked with increased dt values as I started with 60 seconds.
In between, I have changed different physics parameterization schemes, and now the wind direction is improved, although the wind speed is less than the ASCAT wind speed. I am looking forward to your reply.
 

Attachments

  • WRF_WIND_18_30_MAY_chmgd_physics_nested_domain.png
    3.2 MB · Views: 2
  • namelist.input
    4.6 KB · Views: 3
Thank you. Since the wind is close to the surface, there could be some drag that is slowing it down in the model simulation. Take a look at this previous post that discusses a similar issue and see if any of the suggested settings (including using topo_wind=1) are beneficial to your simulation.
 
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