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Inconsistent coordinates in grid.nc

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yuanlian

New member
Hi,

I noticed that the coordinates used in grid.nc were quite inconsistent. For example, lonCell and lonVertex range from -pi to pi for x1.2562 but lonCell becomes 0 to 2*pi for higher resolutions yet lonVertex still ranges from -pi to pi. I am wondering why the grids were defined so differently. Will it lead to any issues in dynamical core solvers since lonCell and lonVertex have difference range for higher resolutions?

I have always dealt with the different coordinates during the post-processing. I thought it would be nice to have something more consistent, though I haven't seen anything apparently wrong with my simulations.

Thanks,
Yuan
 
I think a possible explanation for the inconsistent longitude ranges across resolutions is that we used different codes (or at least, different versions of code) to produce the various meshes available from the mesh download page; the full set of meshes has been generated over a period of some years, and our software has evolved during that time. As to why we've used different longitude ranges for different fields (lonVertex, lonCell, lonEdge), I don't have a good explanation.

In any case, since longitude is a periodic coordinate, the specific choice of range shouldn't make a difference.
 
Hi Michael,

Thanks for the explanation. As far as the model results concerned, I haven't encountered any issues with the difference among lonCell, lonVertex and lonEdge. I just need to be a little careful when performing post-processing ;)

Yuan
 
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