[Tagging] Feature Proposal - RFC - Topographic Prominence

Joseph Eisenberg joseph.eisenberg at gmail.com
Tue Sep 25 00:51:40 UTC 2018

The small sub-summits around the caldera of a tall volcano (eg Mt Fuji) are
a great example of why prominence=* is useful.
I don't think it works call each of those local high points on Mt Fuji's
crater a "hill", if they are all at >3000m elevation with steep slopes
dropping >1000 meters down to the valley or plain below.
But if they are all natural=peak, we need a way to distinguish them,
besides elevation. The highest point on Mt Fuji will have a very high
prominence (>1500 meters), while the other peaks will have <100m
prominence. Prominence separates true mountain peaks from sub-peaks nicely,
in an objective way.

On Tue, Sep 25, 2018 at 9:26 AM John Willis <johnw at mac.com> wrote:

> On Sep 25, 2018, at 5:08 AM, Andy Townsend <ajt1047 at gmail.com> wrote:
> There is an attempt to document what a hill is and how its separated from
> a (natural=)peak by separating them on prominence.
> TL;DR - you are dealing with a very high volume of named “sub-peaks /
> prominences / whatever-mountaineering-term-you-want ” on large mountains
> *and* a large volume of small and modest hills in valley floors or
> otherwise flat terrain - Perhaps prominence can handle them, but please
> remember that this is not *just* about defining sub-peaks of very tall
> mountains - there are a lot of little tiny hills that in some cultures
> would never be named that have officially mapped names in others.
> *****
> There are landscape types *and* cultural naming traditions that lend
> themselves to using =peak exclusively - places with very large mountains
> with easily identifiable points as the top.
> in California, at least down in San Diego, naming almost all mountains
> using =peak is probably acceptable. tiny lumps and bumps on the mountains
> and on the valleys simply aren't named (at least offically, I have looked
> at a lot of topos). Official maps are not cluttered with mountains names.
> I was amazed when I moved to Japan - the mountains are not only much
> denser, but they are very jagged. And since people lived in hamlets around
> each of them for hundreds and hundreds of years, every lump, bump, and
> little hill the size of a 4 story building is a named “mountain”.
> Google even makes fun of it when they made an online ad for “okay google”
> about a tourist family that confused the 30m tall “Mt Fuji” in my town with
> the iconic Mount Fuji when getting directions.
> I was browsing reddit a couple days ago, and someone posted a map from
> 1843 that someone drew of the regions surrounding Mount Fuji. it is roughly
> 400x300 KM.
> https://i.redd.it/p72gso7m90o11.jpg
> every one of those little green bumps is a full =peak.  there are probably
> 5X little bumps and lumps on them that are named. **And then** there are
> the little hills that poke out of a valley floors by 20-50 meters that also
> get officially named - you could hide them behind an average size school
> building - but are named. local natural paper maps have names cluttering up
> every available spot on the paper.
> even modest hills get rendered the same as massive volcanoes.
> https://camo.githubusercontent.com/d3a7f027a0b83fdf143af0569445bb87788d857a/68747470733a2f2f662e636c6f75642e6769746875622e636f6d2f6173736574732f363231323635362f323038363931312f61393431393065362d386536312d313165332d383034372d3534393334653936373363372e6a7067
> Also, several caldera volcanoes are nationally or internationally famous,
> and they have named every little point along their asymmetrical rim - the
> volcano tag for them should be rendered z8, and the smaller hills around
> the top at z16 - but as it stands there is no way to say “these little
> points on the rim are insignificant compared to the 2000m tall volcano
> visible to 20 million people and namesake to thousands of things and
> places, and these 6 little points are only important to people hiking
> nearby. “
> https://camo.githubusercontent.com/f1b781cd91970b27ff390b5355cab2ffa8531578/68747470733a2f2f662e636c6f75642e6769746875622e636f6d2f6173736574732f363231323635362f323038363937382f66353063353562342d386536322d313165332d383932392d3531303536366134633433622e6a7067
> trying to map all of these as =peaks ***reeks*** of data pollution.
> I hope a good solution is found - EVEN IF it is just the mapper’s
> intuition. enough input should provide consensus.
> Javbw
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