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Plotting USGS 3d Elevation Data in GMT

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This post is about plotting high resolution digital elevation model (DEM) data in GMT for high-quality maps. Every time I need to do this, I end up googling around, wasting a bunch of time, so this post mostly serves as a reference for me. First things first, the USGS provides elevation data at numerous resolutions, the most common being 1 arcsecond (roughly 30 meters) and 1/3 arcsecond (roughly 10 meters). Other resolutions exist, but these are the two you will probably use most. Getting the elevation data can be done through the USGS's National Map web service ( https://viewer.nationalmap.gov/basic/#productGroupSearch ). The process is rather simple, just zoom into the area you care about (you can also enter coordinates) and then under " Elevation Products (3DEP)", click which one you want. After clicking 'Find Products', you can go to the Products tab and toggle on and off the footprints of the different maps. They are done in 1 degree squares, so you will need