I have a netcdf file of my computational grid. It is a structured curvilinear grid. When I make a feature layer from a it with the Multidimension Tool toolbox, I cannot get the point locations to plot properly. If I don't tell arcgis what netcdf dimensions to use (i.e. row dimensions option empty) all I get is a single point at the 0,0 origin. If I try to use the xi and yi dimensions, which are the indices of of the netcdf variable that I want to plot (i.e. with row dimensions as xi and yi) I get them to plot with the coordinates as the xi and yi indices instead of latitudes and longitudes.
I have the set of lon – lat variables in my netcdf files, but I cannot select them to be used as the dimensions or the dimension values (the tool box will not see them at all, although they are in the netcdf file).
How can I fix this issue?
Using ArcGIs 10.0.
Best Answer
I have found the answer to my own question. If this works for anybody else who is having the same problem, maybe they can vote up the question or the answer, since I cannot get any points for answering my own question. :)
Easy fix: When I was looking for an answer I saw that populating the "row dimension " in ArcGIS with the dimensions of the netcdf variable solved the problem (as long as you have the dimensions and attributes defined in the netcdf file correctly). So for a Climate and Forecast (CF) Metadata Convention compliant netcdf file this easy fix should work.
A more complex issue: The problem that I had was that I did not have the Coordinates attribute defined for that variable that I was trying to plot. Once I defined lat and lon variables as coordinates for my variable while creating the netcdf file I was able to select them as X Variable and Y Variable in the toolbox.
So in short:
Curvilinear or variably spaced data can be plotted this way. Raster data needs to be evenly spaced.