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LES cloud simulation at extremely fine resolution

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gpetty

New member
I'm completely new to working with WRF (as of yesterday), and I'm hoping that the LES mode will allow me to run an idealized simulation of marine stratocumulus at very fine (~ 1m!) resolution. I'm also hoping that extraneous computation can be kept to a minimum -- single grid, simple LW radiative parameterization, no SW radiation, fixed SST, periodic lateral boundary conditions, liquid-phase-only cloud physics (Kessler).

The purpose is to try to capture something resembling the fine-scale cloud water density structure of marine stratocumulus clouds forced by radiative cooling at cloud top.

I have already found the "shallow convection" variant of the em_les idealized model, which seems to get me pretty close, but there are a lot of parameters in the namelist.input file whose significance/relevance remains unclear to me despite having read the "best practices" page. I have also already found that WRF crashes if I don't set both a SW and LW radiation scheme; it won't let me set just LW.

If anyone has advice on whether WRF can even do sensible things at this resolution, and if so, what things I should watch out for when setting namelist parameters, I'd greatly appreciate it.
 
WRF has been applied for LES simulation at the resolution of around 100m. Some people try to run WRF at resolutions of 50m and 30m for LES simulation. However, I am not aware that WRF can be run at 1m resolution.
As for the namelist options, please find the detailed information in run/README.namelist and in Registry.EM_COMMON. Both files provide explanations of these options.
 
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