[pct-l] Elevation gain

[spiritbear2k@hotmail.com (Ginny & Jim Owen)]

If we're gonna talk about elevation gain let's start with a comment - that 
while the length of someone’s stride may be relevant to measuring distance 
(if they know the exact length of their stride), it’s irrelevant in the 
measurement of elevation gain.

But as Roy pointed out (and I think this was the real point), the limits of 
accuracy for any measurement are defined by the resolution of the measuring 
instrument.  And the finer the resolution of the instrument, the closer the 
measurement approaches the "real" value - it's an asymptotic function. If 
you’re measuring straight-line distance on a map over an area with little or 
no elevation gain, you can get fairly accurate.  If you’re measuring “trail” 
distance from a map, your accuracy deteriorates rapidly as a function of how 
serpentine the trail is (in both horizontal and vertical axes).  The 
"easiest" way to get an “accurate” measurement of real trail length is with 
a measuring wheel and even that has its problems and inaccuracies (been 
there, done that).

Same thing (sorta) with elevation gain/loss – you can pick any 2 points, 
measure the elevations and determine an “elevation gain (or loss)” between 
those two points.  But again, the accuracy of your measurement will depend 
on what might be called a “vertical serpentine factor” – in plain English, 
how many “bumps”, “dips”, "hills", "valleys", etc. exist between the two 
points that you picked for your measurement as well as the accuracy limits 
of the measurement device and/or process.

So let’s start by defining the instrument in question – I was (and still am) 
using a Suunto watch/altimeter.  Personal experience on the CDT was that it 
was a little less accurate than the Avocet that I’d previously used, but was 
acceptable as long as I periodically calibrated it against known points.  
And I did that.  Suunto claims a 10’ accuracy for this puppy – meaning that 
it’s supposed to register elevation gain/loss in 10’ increments. The Suunto 
has a logging function that registers cumulative elevation gains/losses as 
long as it’s turned on.  The logging function operates off the altimeter 
readings – so the accuracy is essentially the same.

Remember those “bumps” & “dips”?  Well, if they’re less than 10’ elevation 
gain/loss, then, at least theoretically, they won’t be counted in the 
cumulative elevation gain numbers.  That means if you walk across 100 5’ 
bumps, there will be 500’ of elevation gain that won’t be counted in the 
cumulative total.  And we crossed a lot of those "bumps", so even my numbers 
are low in that regard.

What I just said is that, for a lot of reasons, my numbers aren’t “exact” 
either.  But I think they’re closer than using the guidebook/Data Book 
numbers to determine “total elevation gain” between any two points on the 
trail.  Especially given the fact that the guidebook and Data Book high and 
low points aren't.

If someone else does what I did, they’ll likely get slightly different 
results due to the differences between their altimeter and mine (among other 
reasons), but it should be in the same general range plus or minus a couple 
percent.

The bottom line here is that while it might be interesting to know the 
“total elevation gain” – like Sly said, it really doesn’t matter in the long 
run cause you’re either gonna hike the trail or you’re not – regardless of 
the elevation gain.

OK – numbers. I found pieces of the notes I kept on the trail, but the rest 
of them are in a box in PA, some of the numbers are questionable (a couple 
times I forgot to turn the log off when we went into town) and toward the 
end (Washington) the logging function started giving me obviously screwy 
numbers (low battery maybe? - or maybe a malfunctioning sensor?).

In any case, the numbers that I gave Brick were totals between specific 
points. The detailed readings are buried in a box, but I kept the totals.  
These are the total elevation gains that I recorded between these particular 
points -

Campo to  	Mt Laguna		 8050
	>	Warner Springs	        17210
	>	Idyllwild		19820
	>	Wrightwood		22440
	>	Agua Dulce		19900
	>	Mojave		        34370
	>	Onyx			22470
	>	Kennedy Meadows	        21440
	>	Lone Pine		18830


I still have some of the more detailed numbers after Lone Pine -
Cottonwood Pass to 	Guyot Creek		4480
		>	Crabtree Meadows	1690
		>	Tyndall Creek		950
		>	Vidette Meadow	        2490
		>	Woods Creek		6270
		>	Pinchot Pass		3230
		>	Mather Pass		3890
		>	San Joachim River	13060
		>	Selden Pass		5300
		>	Mono Creek		3910


Then north of Sierra City it looked like this –
Rt 49 	to 	Chimney Rock	        6800
	>	Bear Creek		2380
	>	creeklet (1261.7)	5890
	>	Belden			6410
	>	spring (1297.6)	        6280
	>	shallow gully(1321.8)	4920
	>	Warren CG		7210
	>	Old Station		8870
	>	(1402.3)		6690
	>	Rt (Burney)		720

And a couple sections in Oregon –  ??? means I don’t necessarily believe the 
numbers so you shouldn’t either –

Shelter Cove to 	Lake (1910.9)		2070
	        >	Brahma Lake		3500
		>	Elk Lake Resort	        2770


Ollallie Lake to 	Red Wolf Pass 	        2780
		>	US 26/Barlow Pass	3630
		>	Timberline		4480
		>	Lolo Pass		5630
		>	Indian Springs Camp	3950
		>	Cascade Locks	        7650 ???

Cascade Locks to 	Rock Creek		7910
		>	(2191.0)		5800
		>	Deer Lake		7990
		>	White Salmon River	4530
		>	Midway Creek		11520 ???
		>	Lutz Lake		9100
		>	White Pass		4690 ???


Finally - I kept these numbers for my own satisfaction – there’s nothing  
“official” about them.  So if anyone has complaints or problems with them, 
you are, as a friend used to say – welcome to fix the problem at your time 
and expense.  In other words, go hike the trail with your own altimeter, 
then come back and tell us about it.


Walk softly,
Jim

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