On Sun, May 24, 2020 at 5:42 AM Sarah Hoffmann <lon...@denofr.de> wrote: > On Sat, May 23, 2020 at 09:58:50PM -0400, Kevin Kenny wrote: > [Australian grading of hiking trails] > > And all five of those grades are sac_scale=hiking, which is why I say > > that's an impossible scale to use for the purpose we're considering. > > That's not correct. If you have a look at > https://wiki.openstreetmap.org/wiki/Key:sac_scale > you'll notice that only from sac_scale=demanding_mountain_hiking the > scale starts to have the requirement "basic alpine expericence" and > "good hiking shoes". > > So: Only Grade 1 and 2 are clear sac_scale=hiking. Grade 4 would map > to sac_scale=mountain_hiking and Grade 5 to > sac_scale=demanding_mountain_hiking. > Grade 3 is a bit inbetween but I'd probably put it under > sac_scale=mountain_hiking to be on the safe side. > > The SAC scale grades 1-3 are quite helpful. It's just the blue scales 4-6 > which are not really applicable in OSM because very few routes of that > scale would fall under the highway=path classification (even under the > catch-all definition of OSM).
The first problem with the sac_scale is that it's not got anything at the low end. For trails in urban and suburban areas, we want to know, for instance, whether the trail might be accessible to the disabled or to small children. That's actually the single biggest problem here. Without delving into a ton of auxiliary information, there's no difference between an urban footway and a wilderness trail! For that reason, 'surface' and 'smoothness' and 'incline' and 'sac_scale' are all trolltags: they destroy fundamental expectations (at least to urbanites) of what a 'path' is. (Those false expectations are responsible for many outdoor accidents in my part of the world - I'm close enough to several large cities that we get many unprepared tourists.) I agree that highway=path and highway=footway are too entrenched, so we're going to be stuck with trolltags. In that case, we need fairly clear and repeatable guidelines for both mappers and data consumers - right now, trying to figure out, 'do I have an urban footpath or a wilderness trail' is a complex endeavour, and mappers aren't really in a position to help. While you can add 'sac_scale' to flag that a path is unsuitable to small children, disabled people, or less-skilled hikers, how do we flag that a path _is_ suitable? (The absence of a tag cannot be the answer, because the absence of a tag conveys at best, "I don't know." It's best never to draw any conclusion at all from the absence of a tag.) Those who aren't hiking geeks may stop reading here, the rest gets more technical: One-line summary: I clearly don't understand sac_scale, but my discussions with the OSMers have done little to clarify it in my mind. I just reread the `sac_scale` page yet again . I'm afraid that I don't find it quite as helpful as you do, even in the domain for which it's intended. It appears to have been awkwardly machine-translated to English from another language. For example, 'acclivity' and 'facile' are both Latinate words that a native speaker would use only when writing in an affected academic style. My university-educated (but geologically-ignorant) wife didn't even know the word 'acclivity' without looking it up! At the higher levels of difficulty, the page focuses on mountain hazards. There's no consideration for slippery or unstable bog bridging, stream crossings (rock-hop or ford: and how deep or fast-moving is the water?); deep mud or quicksand, likelihood of encroaching vegetation, or beaver activity. All of these present objective hazards (falls, drowning, hypothermia) that come into assessing a trail's level of difficulty and danger. The phrase 'single plainly climbing up to second grade' comes across as word salad. I have no idea what the word, "single" refers to. What is "plainly" climbing? I presume that "second grade" is on someone's scale of rock- or ice-climbing difficulty, but have no idea what scale to look at to translate to the YDS that's pretty universal in the US. If it's the UIAA scale, then I can sort of make sense of it: grade II is roughly equivalent to 5.3 on the Yosemite scale. A hiking trail at the technical end of things might have a 5.3 move somewhere, if it's not exposed. If I'm doing anything beyond class 4 (YDS) in an exposed position, I want a belay and a helmet, and that's no longer hiking! [Afterthought - I finally found the original German. 'einzelne einfache Kletterstellen'. Then the following grade (Schwieriges Alpinwandern) says 'Kletterstellen bis II UIAA', so I guessed right on UIAA. I suppose that if you're unaware of the context, 'einzeine' could be single and 'einfache' could be 'plainly', but the translation of the whole phrase on the Wiki is nonsense. Any objections if I edit it to something like: "Isolated easy climbing pitches, up to class 2 on the UIAA scale?" If I were to do that, I'd try to clean up the translation throughout.] The emphasis on footwear is a bit weird. "Solid trekking boots?" I've done a 220-km solo trek through the Adirondacks (including one segment where I started with six days' consumaables) wearing lightweight trail runners. For me, in general, the boots come out only when the snow does. I can see that for SAC grades 5 and 6 that glacier travel is specifically mentioned, so I suppose that the talk of mountaineering boots might make sense there - but for winter hiking, I use strap-on crampons and Sorel pac boots, not hard-shell mountaineering boots. Hard-shell boots are needed for German-technique front-point climbing with ice tools. I don't do that. If I can't negotiate ice with French technique, I'm not going! [Ah, once again, the translation fails. 'Stabile Trekkingschuhe.' 'Trekking shoes' isn't a common phrase in American English; 'robust hiking shoes' or 'stable hiking shoes' is probably a better translation, and that description would tell me to wear my Merrell hiking shoes and not my New Balance trail runners. 'Schuhe' is used consistently in the German, so the puzzling switch from 'shoes' to 'boots' doesn't appear.] I already mentioned that I've encountered others who interpret "sometimes need for hand use to get ahead" means "taking full body weight on the hands" as opposed to the "possible need to use hands for balance" at the previous difficulty level. If you tell me that 'an gewissen Stellen braucht es die Hände zum Vorwärtskommen' means that a typical hiker will need to put hands to the rock in spots, rather than that a seasoned climber will be taking full weight on the hands, I'll believe you: you're a native German speaker. "Progress sometimes impossible without using the hands?" perhaps? At the higher grades, there is a lot of assessment of snow and ice conditions. Is there a way to tag seasonally-varying conditions? I can think of numerous trails that are 'mountain_hiking' or 'demanding_mountain_hiking' in summer, but demand ice axe, crampons, possibly a rope, and the skills to use all of them in winter. (If I have the scale right, that would be at least 'demanding Alpine hiking' in winter.) Everything emphasizes "alpine" experience. What does "alpine" mean in this context? My understanding of the English word can refer to several things, all of which are problematic: Ecozone: The mountains here are lower than the Alps; we have only a handful in the Northeastern US that have true alpine conditions, and none of those is permanently glaciated. The Australians are similarly confused - even the so-called Australian Alps are subalpine. The examples that I posted of difficult and dangerous trails - and they surely are, judging by the number of accidents and even fatalities - are all in either temperate mixed woodland, or in balsam-and-spruce subalpine taiga and Krummholz (Abies balsamea [Balsam-Tanne], Larix laricina [Lärche] and Picea spp. [Fichte] predominate in the canopy, with scattered Betula papyrifera [Amerikanische Weißbirke] and other cold-tolerant deciduous trees in more sheltered locations. The understory is mostly mosses, lycopods and ferns, with scattered thickets of Vaccinium uliginosum [Rauschbeere] and Viburnum lantanoides [I don't think this one has a vulgar name in German - its natural habitat is eastern Canada and the northeastern US. Around here we call it 'witch-hobble'. Schneeballbush is a related species.]). Sport: The sport "alpinism" (Alpinklettern) focuses on roped climbing and glacier travel, which is no longer hiking, so in that sense I would read requiring 'basic alpine experience' as 'this route is too technical to be considered a hiking trail.' Travel style: "Alpine style" travel refers to self-sufficient travel, carrying one's own food, shelter and equipment, as opposed to 'expedition style' where one may an organized and supported expedition. "Alpine style" disdains the use of porters, of Hütten (we really don't have those over here, except for a handful in the White Mountains of New Hampshire and a couple in the Adirondacks of New York) and of fixed climbing aids - so this interpretation would make the "exposed sites may be secured with ropes or chains" comment confusing. Geography: Of course, Alpine with a capital A refers specifically to the Alps. I dismiss this: we're supposed to be coming up with a definition that will apply to the entire planet. (I ignore definitions relating to downhill skiing, or to a supposed human racial type, as being irrelevant.) None of these definitions of 'alpine' is very helpful to me. By any of them, I have very little alpine experience.I'm not into roped climbing. (I permanently damaged one knee, over forty years ago, in a climbing accident, while also learning that developing the finger strength needed stiffened my hands and made me clumsy at my musical instruments. I decided that the sport was not for me.) I've never hiked on a glacier - I don't think there are any within a thousand km of here! I suppose that all my hikes have been "alpine style" in that I've never participated in a supported mountaineering expedition. I've never been to the European Alps. All of my skiing has been Nordic style, and there's not been much of that. The racial definition is offensive - I'll admit to being a member of the _human_ race. Finally, if I do try to tidy up the translation, help me out with a couple of words. The German original looks to be Süddeutsch, verging on Schwyzertütsch, and has a couple of words that I had to look up in Duden. (My German is pretty bad: I learnt just enough to pass a reading test for my mathematics degree, several decades ago.) 'apere Gletscherpassagen' - 'snow-free glacier crossings?' 'Aper' was a new word to me. Google Translate doesn't know it. 'heikles Schrofengelände' - 'difficult talus' or 'talus requiring extreme care?' 'Heikel' and 'Schrofen' were also new to me. I've been solemnly assured by a couple of others that even the hardest trails I've described earlier in the thread are still just 'mountain hiking'. Was that just that the southern Germans I was talking to were proud of the difficulty of trails in the Alps, and reluctant to admit that trails elsewhere in the world might be just as hard? -- 73 de ke9tv/2, Kevin _______________________________________________ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
