I sense a topic for the next Many Mappy Minutes or a BOF at State of the Map US —> cleaning up old imports. I sure appreciate all the knowledge shared here! So much I didn’t know about GNIS data. Martijn
> On Sep 30, 2017, at 11:54 AM, Wolfgang Zenker <[email protected]> > wrote: > > * Carl Anderson <[email protected] <mailto:[email protected]>> > [170930 17:21]: >> A little history on GNIS data, and the Board of Geographic Names. > >> The US Board of Geographic Names manages names for places and features >> shown on US govt maps. They have been using a database to manage the names >> across maps and map scales. That database is the GNIS. > >> The original GNIS data was populated from all text labels shown on USGS >> maps. The most common source was 1:24,000 scale topo quarter quads. Text >> from 1:100,000, 1:250,000 and 1:1,000,000 scale maps and larger were >> included. > >> The stated map accuracy of these scales ( >> https://nationalmap.gov/standards/nmas.html ) is approximately > >> 1:24:000 40 feet >> 1:250,000 416 feet >> 1:500,000 833 feet >> 1:1,000,000 1666 feet > >> The GNIS dataset includes the most precise location for text, when the text >> appears on maps of different scales. > > You can look at the full database entry for an individual GNIS feature > if you search for the GNIS Feature ID at geonames.usgs.gov/apex/f?p=gnispq > <http://geonames.usgs.gov/apex/f?p=gnispq> > > This will give you the source of the database entry, possibly a list of > alternate names, sometimes a note like "location approximate", and > sometimes the history of the decision process if more than one name > had been proposed for the feature. Also documentation of official > name changes. > > One more thing to know about GNIS: entries are never deleted. If a > feature no longer exists, the name gets "(historical)" appended to > it. This may have happened after the feature was imported to OSM, > so it may not show in the OSM database. > > Unfortunately the GNIS database is no longer fully maintained due to > budget constraints, so you can't be sure if features still exist even > if they are not flagged as "(historical)". > > As to mapping in OSM: I usually remove any "(historical)" feature. > For the others, I improve the location if possible, and if the feature > can be represented as an area, I draw that area/polygon. > Instead of deleting the original POI, I now reuse that node as part > of the outline of the feature and only move the tags to the area, so > someone looking at the object details can notice that one of the nodes > is a lot older than the others and still find the osm history of the > feature on that node. > > Wolfgang > ( lyx @ OSM ) > > _______________________________________________ > Talk-us mailing list > [email protected] <mailto:[email protected]> > https://lists.openstreetmap.org/listinfo/talk-us > <https://lists.openstreetmap.org/listinfo/talk-us>
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