Question about the tidal forcing file

[xupeng66]

Hi All,

I have a question regarding the tidal ellipse inclination angle "tide_Cangle" in the forcing file. I am wondering if "tide_Cangle" is the angle between the semi-major axis and east or it is the angle between the semi-major axis and the xi direction.

Thanks

Guangyu

[drivas]

Hello,
I just found this post which, unfortunately, doesn't show any answer. What was your conclusion? Is it the angle with respect to the east or respect to the xi coordinate?
Regards,
drivas

[jcwarner]

i have not looked at the tides files in a long time, but in our tides tools m file we have:

cangleID = netcdf.defVar(nc_init,'tide_Cangle','double',[xrhodimID erhodimID ntidedimID]);
netcdf.putAtt(nc_init,cangleID,'long_name','tidal current inclination angle');
netcdf.putAtt(nc_init,cangleID,'units','degrees between semi-major axis and East');
netcdf.putAtt(nc_init,cangleID,'field','tide_Cangle, scalar, series');

[jcwarner]

and then in set tides you have stuff like:

omega=cff/Tperiod(itide)
DO j=MIN(JstrR,Jstr-1),JendR
DO i=MIN(IstrR,Istr-1),IendR
angle=UV_Tangle(i,j,itide)-angler(i,j) <--------- here it corrects for the grid angle
Cangle=COS(angle)
Sangle=SIN(angle)
phase=omega-UV_Tphase(i,j,itide)
Cphase=COS(phase)
Sphase=SIN(phase)
Uwrk(i,j)=UV_Tmajor(i,j,itide)*Cangle*Cphase- &
& UV_Tminor(i,j,itide)*Sangle*Sphase
Vwrk(i,j)=UV_Tmajor(i,j,itide)*Sangle*Cphase+ &
& UV_Tminor(i,j,itide)*Cangle*Sphase
.....