Temperature significantly near land areas

[hoangha]

Hello

I run for real domain in East Sea of Vietnam with resolution of 9 km, 12 vertical layers.
+ Oceanic variables including temperature, salt, zeta, u and v getting from HYCOM.
+ All atmospheric variables including 'Uwind','Vwind','Pair','Tair','Qair','rain','swrad','lwrad','bhflux','bwflux','swflux'..are set 0 (no interaction with atmospheric)

However, just after 0.5 hour of simulation, temperature significantly increase only near land areas (Fig.0.5 hour. jpg). It is quite weird.

(even, I ]provide real atmospheric variables after running from WRF, temperature still significantly increase only near land areas)

Could you give me any comments?

Thanks

[jcwarner]

a couple of things jump out here.
- first it is best to put temp scales the same so we can see the differences.
- second it seems a lot of cooling on east side, looks like a BC issue.
- for the temp spikes near land: how is wrf data interpolated to roms grid? we had issues with the coupling at first, but then realized that wrf heat and momentum fluxes on land can not be used to interpolate to the ocean. The wrf and roms land/sea masking is most likely different, so you have to use only wrf ocean points to interpolate to roms.
- when you have atm fluxes to 0, do you nudge to hycom data ? how is hycom data interpolated to roms grid?

-john

[susonic]

I think your set up for boundary condition is not common set up.

Why don't you give below boundary condition and see if the result change.

For free surface, Chapman
2d momentum(Ubar, Vbar), Flather
3d momentum(Uvel, Vvel), Clamp
MTKE, Gradient
Tvar (TS), Clamp

-JH

[hoangha]

Thank you very much for your useful comments.

I found above problem was caused by "mask" itself. when I created "grid file" with new version of Matlab (2014a) that problem is gone.
I still do not know why it happen because when I check mask value of both "creating by old version of Matlab, 2013a" (proplem one))and "creating by new version of Matlab, 2014a") mask is exactly the same.

The Matlab code bellow I use to write "mask" in "grid file""

nw{'mask_rho'} = ncdouble('eta_rho', 'xi_rho');
nw{'mask_rho'}.long_name = ncchar('mask on RHO-points');
nw{'mask_rho'}.long_name = 'mask on RHO-points';
nw{'mask_rho'}.option_0 = ncchar('land');
nw{'mask_rho'}.option_0 = 'land';
nw{'mask_rho'}.option_1 = ncchar('water');
nw{'mask_rho'}.option_1 = 'water';


Many thanks

[corvianawatie]

Thank you very much for your useful comments.

I found above problem was caused by "mask" itself. when I created "grid file" with new version of Matlab (2014a) that problem is gone.
I still do not know why it happen because when I check mask value of both "creating by old version of Matlab, 2013a" (proplem one))and "creating by new version of Matlab, 2014a") mask is exactly the same.

The Matlab code bellow I use to write "mask" in "grid file""

nw{'mask_rho'} = ncdouble('eta_rho', 'xi_rho');
nw{'mask_rho'}.long_name = ncchar('mask on RHO-points');
nw{'mask_rho'}.long_name = 'mask on RHO-points';
nw{'mask_rho'}.option_0 = ncchar('land');
nw{'mask_rho'}.option_0 = 'land';
nw{'mask_rho'}.option_1 = ncchar('water');
nw{'mask_rho'}.option_1 = 'water';


Many thanks

Dear all, I experienced the same problem. I tried to run using analytical temperature and salinity (3D), so the model domain have the same temperature and salinity value (14 degC and 35 PSU). I put no forcing at all. However, there are abnormal increasing & decreasing both on temperature and salinity value. I didnt turn on CPP NONLIN_EOS. Also, i thought that I have used the correct masking grid. I build the grid using GRIDBUILDER.

What might be the problem?