Idealized WRF Terrain

[smeech84]

Hi,

I'm using WRF in idealized mode and I'm wondering what 'flat idealized terrain' really is. Is it like a grass field and a low canopy? etc.

What are the specific WRF parameter values used to define the idealized flat surface? Example parameters are surface roughness and/or canopy height or other parameters like Bowen ratio, albedo, etc.

Thanks,
Scott

 

[Ming Chen]

Hi Scott,
'flat idealized terrain' means there is no topography, i.e., HGT == 0 everywhere. As for other parameters, for example surface roughness and/or canopy height etc., you may notice that many ideal cases such as em_b_wave, em_les, em_quarter_ss don't activate surface scheme. A constant surface drag and heat flux are specified for such ideal case run. I guess this is what "flat idealized terrain" means.

 

[smeech84]

Hi Ming, thanks for your reply.

A constant surface drag and heat flux are specified for such ideal case run. I guess this is what "flat idealized terrain" means.

Do you know how to find these constants? This would be exactly what I would be trying to find out.

 

[Ming Chen]

They are specified in namelist.inut. Let's take em_les as an example: in the namelist.inout, you can find the line below:
tke_heat_flux = 0.24, 0.24, 0.24,
which specifies surface heat flux for the development of free CBL

Different cases may have different options. Please take a look at the README file for individual cases.