On Sun, Sep 23, 2018 at 5:40 PM Joseph Eisenberg <[email protected]> wrote: > Yes, “prominence” here is a technical term that has only a partially > connection to the subjective “importance” of a peak. > > In general, all peaks with high topographic prominence are considered > important by local people (if anyone lives near them) and mountain climbers, > but some peaks with low topographic prominence are also well-known, eg the > Matterhorn. > > I see that the old, abandoned proposal also suggests the possibility of > making a relation to show the parent peak and key col. These sort of > relations may not be useful to data users, but they might help other mappers > to verify the prominence data. > > Personally, I won’t add new relations when the key col and parent peak are > close by, but I will if they are far away.
Exactly. None of our data model is set up to say, "you must map all features of a given place." It's more, "if you're mapping *this*, consider mapping *that* as well, and here's how to represent it." And yes, when key col and parent peak are distant, it gets weird. As a quick test, I looked up Slide Mountain in the Catskill Mountains of New York https://www.openstreetmap.org/node/357602650 elevation 1276 m, prominence 1000 m. I would have guessed that its line parent would be on the way to Killington Peak, Vermont https://www.openstreetmap.org/node/3139475460, which is both the nearest higher peak and the nearest more prominent peak, but in fact, the deep valleys of the Hudson and Mohawk rivers mean that the line leads away, with a key col somwhere near https://www.openstreetmap.org/#map=15/42.1653/-76.8190 and the next higher point being an insignificant knoll in the Monongahela National Forest in West Virginia. Who knew? By contrast, it mighn't be worthwhile mapping the key col and line parent for Hunter Mountain https://www.openstreetmap.org/node/357598537 - its parent is Slide Mountain (link above) and the key col is somewhere in the pass near the Bellearyre ski resort https://www.openstreetmap.org/#map=16/42.1447/-74.4915&layers=N In any case, the point remains that topographic prominence is a completely objective metric; it can be computed from a sufficiently accurate DEM; but is computation is sufficiently onerous that it's worthwhile capturing and recording the results. _______________________________________________ Tagging mailing list [email protected] https://lists.openstreetmap.org/listinfo/tagging
