View Full Version : Average Elevation of Entire AT?
Hi,
I'm a previous thru-hiker but new to here and have searched high and low, both on this site and on Google, for any estimations on the total average elevation of the AT, but to no avail. The PCT is said to sit at an average of 6,700 feet (+/-, obviously), but there's nothing in regards to the AT. All I find is one discussion after the next about the total elevation gain (i.e., equivalent to climbing 16 Mount Everests, yada, yada, yada...). Has anyone ever read about this or attempted to figure it out? The knowledge would be merely for poops and giggles and nothing more. Any estimations out there? Anything remotely accurate?
Thanks!
Uriah
Following. I don't know if it is accurate but I found this.
http://equipped.outdoors.org/2013/10/total-elevation-gainloss-on-appalachian.html
Also, I found someone cite the average elevation gain/loss per mile for the state of GA in an explanation on why Georgia is not easy. I cannot find it here on WB now. Does anyone know where I can find the elevation gain/loss per mile per state?
fiddlehead
01-12-2015, 20:45
Would be a good guessing game.
I'll guess 3,800' for a start.
I'm sure the stat guys can figure this out.
Mine is just a wild guess, with nothing to back it up except a few thru's and a wild guess.
fiddlehead
01-12-2015, 20:46
ON second thought, I'm probably a little high (on my estimate)
ON second thought, I'm probably a little high (on my estimate)
That made me smile, your "on my estimation" clarification. Yeah, I've estimated closer to 3,000 feet, but really have NO clue whatsoever.
Sorry, my post had no relevance to this topic. I thought you asked a different question.
Sorry, my post had no relevance to this topic. I thought you asked a different question.
No worries...I probably should've bolded the key point, total average elevation. I realize it's next to impossible to get an accurate figure, but it may be more accurate than the trail's total gain.
HooKooDooKu
01-12-2015, 21:06
The estimate is going to vary greatly by region.
I've got a trace of the AT in Google Earth, and when I sort of do a spot check, it seems like an average in places like TN, NC, and VA, the elevation seems to average something around 3,000' to 4,000'. But head up to NY and the elevation doesn't appear to get over 1,000' Push on to MN and the elevation seems to average around 1,500'.
Interesting. The likely average elevation of the AT is less than the lowest point on the CDT.
peakbagger
01-12-2015, 21:10
The problem with elevation changes is that its dependent upon the how many points along the trail are you averaging. If you take the elevation of Springer and the elevation of Katahdin and divide by two that result is an average elevation. Or you could take the elevation at each state line and divide by the number and that would give you a different average. You then go to every mile and take the average and get a different value. Then you can go to every foot and get a different answer.
At one time Mr Parkay posted the AT, PCT and CDT comparative elevation profile. It was quite fascinating.
Guthook posted this in this thread
http://www.whiteblaze.net/forum/showthread.php/54822-Steepest-part-of-the-AT
From what I gather, the AT is steeper, with more ups and downs, per mile than the PCT, which is designed for horses and mules.
http://www.guthookhikes.com/2015/01/what-are-the-steepest-climbs-on-the-at-and-pct.html
AO2134, here is a link to the article here on WB with the state by state breakdown (it's in Table 2):
http://www.whiteblaze.net/forum/content.php/49
Following. I don't know if it is accurate but I found this.
http://equipped.outdoors.org/2013/10/total-elevation-gainloss-on-appalachian.html
Also, I found someone cite the average elevation gain/loss per mile for the state of GA in an explanation on why Georgia is not easy. I cannot find it here on WB now. Does anyone know where I can find the elevation gain/loss per mile per state?
AO2134, here is a link to the article here on WB with the state by state breakdown (it's in Table 2):
http://www.whiteblaze.net/forum/content.php/49
Thank you sir.
And Uriah (http://www.whiteblaze.net/forum/member.php/56712-Uriah), I am sorry for commandeering your post.
atraildreamer
01-13-2015, 11:52
Uriah, It's listed on the WB home page under: AT Articles - Data and Schedules
http://www.whiteblaze.net/forum/content.php/19-data-and-schedules
Also, the elevation gain and loss is equal to 11 Everests up and 11 Everests down.
The mileages will be a bit off as the the trail has been re-routed, but the elevations of the major points are the same.
Updating the article(s) is a future project when time permits.
Traveler
01-13-2015, 12:19
Hi,
I'm a previous thru-hiker but new to here and have searched high and low, both on this site and on Google, for any estimations on the total average elevation of the AT, but to no avail. The PCT is said to sit at an average of 6,700 feet (+/-, obviously), but there's nothing in regards to the AT. All I find is one discussion after the next about the total elevation gain (i.e., equivalent to climbing 16 Mount Everests, yada, yada, yada...). Has anyone ever read about this or attempted to figure it out? The knowledge would be merely for poops and giggles and nothing more. Any estimations out there? Anything remotely accurate?
Uriah
Taking a stab using lowest/highest point per state, the average elevation equals 2,180.3 feet. This is a non-scientific, non-surveyed SWAG.
postholer.com
01-13-2015, 12:23
2406 feet.
Here are some interesting AT Factoids (http://postholer.com/forum/viewtopic.php?f=22&t=2684) and PCT Factoids (http://postholer.com/forum/viewtopic.php?f=2&t=2685). Elevation info is at the bottom of each article.
-postholer
Ultimately I suppose finding an average elevation comes down to the number of measurement points considered. If the AT were laid down as one single long-ass track (as it is), wouldn't a GPS unit or its software be capable of a figure? It surprises me none of the uber analytical/mathematical types, many of whom have hiked the trail, haven't gone about calculating this, first laying down a complete GPS track of the trail, then doing the math. Then again, I suspect we escape to the woods to avoid such problems!
2406 feet. Here are some interesting AT Factoids (http://postholer.com/forum/viewtopic.php?f=22&t=2684) and PCT Factoids (http://postholer.com/forum/viewtopic.php?f=2&t=2685). Elevation info is at the bottom of each article. -postholer
Thanks Postholer! I should have known to visit your site first!
Odd Man Out
01-13-2015, 12:59
At one point I had downloaded some data for a bunch of waypoints along the AT (1509 of them). I don't know where the data came from and so I don't know how accurate or up to date it is, but it's the best I have.
For each waypoint I have miles from Springer and Elevation. So I copied these data to a new spreadsheet (columns A, B, and C). In column D I have a formula to calculate the distance (in miles) of the section ending at that waypoint. In column E, I have a formula to estimate the average elevation of that section (average of the beginning and ending elevation of that section). You can't just average these as each section is a different length, so I take a weighted average by multiplying the section distance by the section elevation (column F) and add that up (end of column F). I am essentially calculating the area under the elevation profile graph (units of mile-ft). Then if you divide the area by the length of the trail, you get the average elevation in ft. The answer is 2404 ft.
https://www.dropbox.com/s/kqj88tsg60ck09k/ATAvgElev.xlsx?dl=0
Odd Man Out
01-13-2015, 13:01
PS. Given the uncertainties in the measurements and data, it would be reasonable to report the average elevation as 2400 ft.
postholer.com
01-13-2015, 13:51
Interesting. The likely average elevation of the AT is less than the lowest point on the CDT.
AT avg elev: 2,406
CDT lowest elev: 4,192
Yeah, big difference there!
-postholer
Odd Man Out
01-13-2015, 13:55
...Also, the elevation gain and loss is equal to 11 Everests up and 11 Everests down.
In this thread, some people are discussion elevation gain and loss while others are discussion average elevation.
As for the gain and loss figures, MapMan's figure of 515,000 ft up and 515,000 ft down seems to be the best data as it did not ignore the PUDS between waypoints.
But I always thought the "11 Everests" claim to be an understatement. First, if you divided the height of Everest by the 515,000 number you get 17.7 Everests, not 11 (I think that 11 Everest number was based on the older elevation gain/loss data). But you can do even better. You don't climb Everest starting at sea level. You probably start at the Lukla Airport (9382 ft), so your net elevation gain to the summit is "only" 19,647 ft. By this measure, the AT is like climbing Everest 26.2 times. Of course this ignores the fact that a climber will go part way up and down the mountain many times to acclimate to elevation, but ignoring that detail, you can make the AT sound even harder! And if I'm figuring this correctly, the AT is steeper. The AT has an average grade of about 9% by these numbers. But if the trek from Lukla to the summit and back is about about 100 miles, this gives an average grade of about 7.5%.
Postholer calls it 2,406. Out Man Out calls it 2,404. I guess that means we average it out to 2,405 feet!
Thanks for the input, all.
atraildreamer
01-14-2015, 18:59
Ultimately I suppose finding an average elevation comes down to the number of measurement points considered. If the AT were laid down as one single long-ass track (as it is), wouldn't a GPS unit or its software be capable of a figure? It surprises me none of the uber analytical/mathematical types, many of whom have hiked the trail, haven't gone about calculating this, first laying down a complete GPS track of the trail, then doing the math. Then again, I suspect we escape to the woods to avoid such problems!
The average elevation is easily found: :-?
The lowest point on the AT is located at the Trailside Museum, Route 9, NY at mile 1398.9 (NOBO) at 163 feet above sea level.
The highest point on the trail is Clingman's Dome at mile 199.1 (NOBO) at 6,655 feet above sea level.
The average is: (6,655' - 163')/2 = 3,246 feet above sea level.
My Elevations article(s) consist of 2,585 elevation points covering 2185.9 miles of the AT. That is an average of one elevation point every 0.85 miles.
Please note that the mileage figures have changed due to trail rerouting, but the elevations remain the same for all the major peaks and locations.
If every point on the trail could be generated as a gps track, then you could have an infinite number of data points to generate elevation graphs. If you had a gps point for every 3-foot increment, (1 yard), of the AT, then you would have to have a device that would be capable of storing 3,847,184 data points! :eek: What happens if you drop the unit, the batteries die or the data is erased? :o:(:mad:
Don't over think this. You are not programming a cruise-missile for a precision strike. You are suppose to be enjoying the walk! :sun
The data points are already out there for you to use. They are called white blazes. Follow them and you'll be on the AT! :)
postholer.com
01-14-2015, 20:06
The average elevation is easily found: :-?
The average is: (6,655' - 163')/2 = 3,246 feet above sea level.
My Elevations article(s) consist of 2,585 elevation points covering 2185.9 miles of the AT. That is an average of one elevation point every 0.85 miles.
Eh?
The formula you're using has nothing to do with averages. It's not a mean, a mode, median or a range.
mean average = sum of items / number of items
Using only 2 elevation points to get the average elevation of a 2,180 mile trail will only ensure failure. You would have much better results using your 2,585 points. I use over 276,000 points.
-postholer
Odd Man Out
01-15-2015, 00:22
Eh?
The formula you're using has nothing to do with averages. It's not a mean, a mode, median or a range.
mean average = sum of items / number of items
Using only 2 elevation points to get the average elevation of a 2,180 mile trail will only ensure failure. You would have much better results using your 2,585 points. I use over 276,000 points.
-postholer
I used the weighted average method with 1500 points and got the same answer as Postholer. If I just did a regular average of the points, it would come in about 40 feet too high.
atraildreamer
01-15-2015, 13:30
Eh?
The formula you're using has nothing to do with averages. It's not a mean, a mode, median or a range.
mean average = sum of items / number of items
Using only 2 elevation points to get the average elevation of a 2,180 mile trail will only ensure failure. You would have much better results using your 2,585 points. I use over 276,000 points.
-postholer
OK, I stand corrected. The number I gave you, 3,246 feet, is the median value. The mean value is what your formula generates.
From: http://www.purplemath.com/modules/meanmode.htm
"The "mean" is the "average" you're used to, where you add up all the numbers and then divide by the number of numbers. The "median" is the "middle" value in the list of numbers. To find the median, your numbers have to be listed in numerical order, so you may have to rewrite your list first. The "mode" is the value that occurs most often. If no number is repeated, then there is no mode for the list.
The "range" is just the difference between the largest and smallest values."
Plugging your formula into my spreadsheet I got 6,230,577 feet as the sum of all recorded elevations. Divided by 2,585 data points gives a result of 2,410.28 feet.
The difference in values can be attributed to the different sizes of the database used and trail re-routings.
postholer.com
01-15-2015, 20:43
Plugging your formula into my spreadsheet I got 6,230,577 feet as the sum of all recorded elevations. Divided by 2,585 data points gives a result of 2,410.28 feet.
Ooooooh, that's sooo much better. You, Odd Man Out and I all arrived at pretty much the same number using different data sets. Odd Man Out's method was particularly interesting.
OK, I stand corrected. The number I gave you, 3,246 feet, is the median value. The mean value is what your formula generates.
The Median value is (2 + 1) / 2 = 1.5. The 1.5 value of 6,655 and 163 is, ironically, it's mean, (6655 + 163) / 2 = 3409
The Mode is 6655 or 163
The Range is 6655 - 163 = 6492
Your orignal statement of (6,655' - 163')/2 = 3,246, is not relevant to averages at all. Just bad math! :) We all do it, no harm done!
-postholer
atraildreamer
01-16-2015, 14:13
Ooooooh, that's sooo much better. You, Odd Man Out and I all arrived at pretty much the same number using different data sets. Odd Man Out's method was particularly interesting.
The Median value is (2 + 1) / 2 = 1.5. The 1.5 value of 6,655 and 163 is, ironically, it's mean, (6655 + 163) / 2 = 3409
The Mode is 6655 or 163
The Range is 6655 - 163 = 6492
Your orignal statement of (6,655' - 163')/2 = 3,246, is not relevant to averages at all. Just bad math! :) We all do it, no harm done!
-postholer
If this keeps up, we are going to need a Cray Supercomputer to hike the AT! :eek:
My eyes still ache from recording all of those data points! :cool: :)
How did get 200,000+ data points? :confused:
Odd Man Out
01-16-2015, 14:40
Ooooooh, that's sooo much better. You, Odd Man Out and I all arrived at pretty much the same number using different data sets. Odd Man Out's method was particularly interesting.
That was per-calculus from HS (calculating an area under a curve). Who would have thought I could use it here???
atraildreamer
01-16-2015, 14:52
OK, I stand corrected. The number I gave you, 3,246 feet, is the median value. The mean value is what your formula generates.
From: http://www.purplemath.com/modules/meanmode.htm
"The "mean" is the "average" you're used to, where you add up all the numbers and then divide by the number of numbers. The "median" is the "middle" value in the list of numbers. To find the median, your numbers have to be listed in numerical order, so you may have to rewrite your list first. The "mode" is the value that occurs most often. If no number is repeated, then there is no mode for the list.
The "range" is just the difference between the largest and smallest values."
Plugging your formula into my spreadsheet I got 6,230,577 feet as the sum of all recorded elevations. Divided by 2,585 data points gives a result of 2,410.28 feet.
The difference in values can be attributed to the different sizes of the database used and trail re-routings.
I just took another look at my spreadsheet and realized that the 2,410.28 feet was calculated including the elevations of the 8.8 mile approach trail from Amicalola Falls State Park to the summit of Springer, the southern start of the AT.
If the results are recalculated omitting the approach trail, the sum of all recorded elevations is 6,173,415 feet and division by 2,569 data points (omitting 16 data points of the approach trail) gives a result of 2,403.042 feet.
Sorry about that! :o
Alligator
01-16-2015, 22:21
I am confident ArcMap would be able to calculate the value if you plugged in the centerline layer for the AT, although you might need the underlying elevation layer.
If you calculate the variance of the points on the centerline and choose a +/- value to estimate the mean, say +/-20 ft, you could figure out how many random points are actually necessary to estimate the mean.