open TELEMAC-MASCARET The mathematically superior suite of solvers

Hi,

i've set up a dummy t2d case to generate a binary winds file from ECMWF data.
the geometry file is in lon-lat coordinates (attached). I put in the t2d.cas file the relevant keywords,
SPHERICAL COORDINATES = YES
GEOGRAPHIC SYSTEM = 1 / WGS84 LAT LONG
SPATIAL PROJECTION TYPE = 3 / LAT-LONG
RESULT FILE IN LONGITUDE-LATITUDE = YES

but for some reason, when the sim starts, I get this message in the printout:
READ_MESH_COORD :
COORDINATES CHANGED INTO MERCATOR PROJECTION
WITH LATITUDE OF ORIGIN POINT = 48.000000000000000
AND LONGITUDE OF ORIGIN POINT = 0.0000000000000000

any ideas?

Cheers,

Hi,

please disregard the previous msg. I decided to resort to writing the binary file using pputils

Hello,

Just to let you know why LATITUDE OF ORIGIN POINT = 48.000000000000000 and LONGITUDE OF ORIGIN POINT = 0.0000000000000000 are written, they are default value for keywords LATITUDE OF ORIGIN POINT and LONGITUDE OF ORIGIN POINT.

As you set
SPHERICAL COORDINATES = YES
SPATIAL PROJECTION TYPE = 3 / LAT-LONG
and TELEMAC solves the equations in Mercator projection, if it is not already in Mercator coordinates, these is a conversion from longitude/latitude to these coordinates.

FYI, the keyword GEOGRAPHIC SYSTEM is only used when you have to interpolate tidal constituents on your grid if you want to model tide from tidal database.
But if you use SPHERICAL COORDINATES = YES, it should be set to 5 (automatically done if not already set).

Chi-Tuan