In reply to ruari88:
It seems I got carried away thinking through this, so feel free to skip this post :P
I probably shouldn't feed the flames of this thread, but anyway... (these points are more 'things it seems people think from reading this thread' than pronouncements - I am still moderately agnostic about UK mixed climbing on summer routes)
Definitions:
Dry tooling = climbing with tools in Summer (not 'out of condition' mixed climbing)
Mixed climbing = climbing with tools in Winter with snow/ice (can be 'in condition' or 'out of condition', with arguments about this)
It seems nobody believes dry-tooling on established rock routes is OK. In any event, with a few well-publicised exceptions, it seems nobody does dry-tooling outside of established venues.
I would argue that the large-scale features of rock has value to the general public (mountains, dramatic crags etc).
I would argue that the small-scale features of rock (that tiny crimp, hand jam, wobbly flake belay) is only of interest to climbers.
I would finally argue that wildlife on those cliffs is of general interest again (birds, alpine flowers etc).
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Summer climbing:
Damage to rock: Limited, takes a fairly large number of climbers to polish a route
Damage to wildlife: Extensive when routes are cleared? Potential significant environmental destruction to rare alpine plants?
Damage to aesthetics: Depends on your opinion of 'clean' vs 'mossy' route? Probably only climbers notice/care?
Winter climbing:
Damage to rock: Scratching (possibly significant) on 'mixed' routes? No damage on pure ice/snow routes. Damage possibly worse on mixed routes when snow coats rocks, hiding holds?
Damage to wildlife: If climbed when turf is frozen, extremely limited if careful (no careless clearing of cracks etc). If climbed on unfrozen turf, significant environmental damage (unacceptable?). Vegetation does not need 'clearing' as it is part of the climb.
Damage to aesthetics: Scratches
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So my main questions would be:
a1) How environmentally destructive is summer rock route creation/gardening on mountain crags?
b2) How environmentally destructive is winter climbing, assuming turf is only climbed when in condition?
c1) How damaging are scratches from ice tools on summer routes - is it purely aesthetic or does it damage the climb/change grades (chipping, removal of loose holds, polishing cracks etc.)? Is it worse than chalk on boulders?
c2) Is this damage only of interest/concern to climbers, or is it clearly visible at a distance/of interest to the general public? As somehow who hasn't been climbing that long, I still find it hard to see the bolts on a wall 3m above me, so stuff is probably a lot more obvious to climbers than non-climbers :P
d1) How damaging is gardening/cleaning of summer routes to winter climbing on those routes?
d2) How much damage does summer climbing do to the rock? (this one, I guess, is not as much per climber as mixed climbing)
e) I have avoided talk of 'condition' outside of frozen/non-frozen turf (which is clearer?), but is there any reason to demand 'white' conditions for mixed climbing when it seems it doesn't provide additional protection to the rock (and possibly the opposite)? Other than limiting the number of people doing it, but we could equally say that mixed routes could only be dry-tooled on one Sunday every three months; I would argue either it is OK or it isn't?
It sounds like mountain crags have their own set of traditions and environmental considerations (not that I have done any!), and therefore a discussion about ethics on climbing on mountain crags should consider all forms of climbing in that context.
Since all forms of climbing cause damage, I guess the only fair way to decide what is acceptable is to decide how much damage is acceptable for our own selfish climbing pleasure, and not do things beyond that (and 'tradition' arguably shouldn't come into it).
One outcome of this thread is I am beginning to realise how much gardening goes into summer climbing, how artificial a 'crag' can be (even without bolts), and considering more carefully the environmental impact (in most places I guess it is not so bad, but on big cliffs summer climbing may be quite environmentally destructive?)
Slightly unrelated: The other thing I wonder; do people think of climbs as temporary? I kind of assume that all of the climbs I do have a limited number of ascents, and that once enough people have enjoyed them they will become extremely polished and not so much fun any more (I may be biased due to the small number of outdoor climbing I have done involving shiny 'easy' stuff at Chudleigh and Font :P )