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The problem about projection【regular_ll】

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Yonghang Xie

New member
In one case, I try to make a land use file where I do the simulation to change the geogrid file from USGS.

I made my file from the .shp file by GIS, and then use the program of write_geogrid.o
However, I confused about the projection' regular_ll' that was used in the index file.
Because I can not find the projection of ' regular_ll' in the GIS and some other references.
As a result, the data which I made by myself could not match and instead of the domain well. (see the attached files)

Can you tell me something about the projection regular_ll, or give some advice about the land use change simulation experiment.

View attachment d1.landuse_oringinal.pdf
View attachment d1.0604miyagilanduse_used my data.pdf

regular_ll means the data is on regular lat-lon grids. It doesn't refer to a specific map projection.

Ming Chen
It may help to note that the "regular_ll" projection in the WPS corresponds to a Cylindrical Equidistant or Plate Carrée projection. The "ll" is our abbreviation for "latitude-longitude".