[Wrf-users] properly removing topography from a restart simulation?

[Marcella, Marc]

Hi wrfusers,

I am trying to remove topography over Taiwan in a WRF simulation where I restart from a prior run to simulate the effects on a typhoon traversing the region.  The procedure I follow is to remove the topography (HGT_M, VAR_SSO, and SLOPECAT variables) in geogrid, re-run metgrid.exe, then re-run real.exe.  I checked the geo.nc, met.nc files, and the real input files---all show the topography variables over the region as zeroed out.  I then am sure to remove the topography from the wrfrst.nc file that the simulation is restarting from.  

When I run the model however, the results do look slightly different than a simulation with topography but not significant given the drastic change (from having topo go from 3km to 0km). Similarly, the results still show a barrier of sorts when the wind/rainfield comes ashore.  When I check the restart files created after the fact, I see that the topography is still 0 but the surface pressure over the island appears as if mountains are there as it is very low (~800mb) as is the sfc pressure in the met_em.nc files.  My question is, am I properly removing the topography? Or are there other variables that also must be zeroed out to mimic a 0km island?  And, is there some other definitive check I can perform to ensure that this simulation is actually not seeing the topography?

Any help would be greatly appreciated. 

Thanks,
Marc