I have some topography data surrounding olympus mons on mars that i’d like to use with the gmt grdflexure module. The topography data is currently in geographic coordinates, but I understand that grdflexure requires cartesian coordinates? What is the best way to convert this properly? I am a bit confused with which projection is best to use and how best to handle the PROJ_ELLIPSOID parameter. Thank you in advance!
If your grid is geographic, convert distances to meters by supplying -fflags instead. netCDF COARDS geographic grids will automatically be recognized as geographic.
Ah I misunderstood it, thanks for the response! In terms of the martian ellipsoid, do you by any chance know if this code is enough (will need to multiply by 0.38 to scale for martian gravity afterwards), or have I missed something:
gmt set PROJ_ELLIPSOID=Mars
gmt grdflexure olympus_mons_topo.grd -Gte_80k.grd -E80000 -D3500/2900/2900/0
apologies for the simple question, the coordinate system is confusing me and i’m not sure if the paramter set PROJ_ELLIPSOID=Mars is doing anything/ working correctly.
Not sure but I think that the ellipsoid is only used to properly convert the longitute and latitude to distances. Nothing else. I don’t think that it is used to adjust to the martian gravity.