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Find a data web source that hosts a WMS server (go to an ice cream vendor). You can find WMS servers through hearsay, or via catalog services. OpenEarth provides a limited list to start with. We will use the Shuttle Radar Topography Mission datasets hosted at the Woods Hole Institute THREDDS OPeNDAP server as example in this primer. THREDDS OPeNDAP servers can be configured to serve WMS for orthogonal datasets with proper geographic information.
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