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saimyoji
01-19-2008, 11:17
Do you really need those profiles on your TOPO map? Why?

Pedaling Fool
01-19-2008, 11:37
The elevation profiles are probably the most useless feature on the map, yet the most looked at. They're just fun to look at, but, again, useless.
The contour lines are pretty neat too, but most AT maps use the wrong scale for the terrain, the best example of this is the map set for NH, the map does not indicate the contour interval, but if you figure it out by looking at the lines it equates to 20 feet per line; that's crazy for that area. What were they thinking?????

Kirby
01-19-2008, 11:53
Profile maps are fun to look at, and they can somewhat help you plan your day, but they can easily deceive you, so take them with a grain of salt.

Kirby

4eyedbuzzard
01-19-2008, 11:56
I think they're just an easier representation of the elevation change "difficulty" of a section of trail. Useful to some degree in planning how far to hike, what your pace may turn out to be, etc.

rafe
01-19-2008, 12:12
Do you really need those profiles on your TOPO map? Why?

What 4eyed said. Total effort isn't just distance, it's elevation change as well.

10-K
01-19-2008, 12:12
I like the profiles and find them a good way of knowing in a general sense what I'm in for up ahead. They don't show every up and down but when I'm slogging up a hill it's nice to know approximately how far I've got to slog.


Thanks
Thomas

ChinMusic
01-19-2008, 12:24
They don't show every up and down but when I'm slogging up a hill it's nice to know approximately how far I've got to slog.

Mentally, this is important to me too. I like knowing what I'm in for. I also like the elevation profiles as a planning tool. All miles are NOT equal.

Skyline
01-19-2008, 12:37
I treat the profiles as a general guide rather than an accurate description of what's ahead. I like to prepare mentally for big elevation changes.

Some AT maintaining clubs have great maps, and the elevation profiles are almost spot-on. Others leave much to the imagination.

Once the ATC's GPS project is complete and all maps include that data to improve their accuracy perhaps we can put more faith in the elevation profiles. Until then, they have a value but they just shouldn't be thought of as a kind of legal "contract." I'd also like to see the maps standardized from Georgia to Maine, but that may be asking a lot.

Bearpaw
01-19-2008, 12:45
A lot of hikers, maybe MOST AT hikers, don't know how to read a countour map. They don't equate all those brown squiggly lines with the shape of the terrain around them. This is much MORE of an issue in the east, where you can seldom see the terrain around you for the heavy tree cover.

Some don't even understand that you can add the number of contour lines up and multiply by the contour interval to determine elevation gain. For these folks, elevation profiles can be helpful.

For me, well, I can read the the contours, or I can read the profiles. Profiles are easier.

The new BMT data book shows elevations of all noted features. This serves a similar function. But a profile map is definitely easier for most folks.

Now as far as the accuracy goes, well, it varies a lot from map to map, particularly depending on how OLD the map is. On my '99 thru-hike, the topos were updated decently, but it seemed that many of the profiles were several years old and didn't match up at with the topo OR the dirt beneath my feet. But it is better than nothing IMO.

Pedaling Fool
01-19-2008, 12:45
...I'd also like to see the maps standardized from Georgia to Maine, but that may be asking a lot.
I too would like to see this, all maps have good features that should be incorporated into a standarized map set. However, currently the best maps IMHO, are MAP SET 1 - 4 that cover the area between Davenport Gap to Damascus, Va.

DuctTape
01-19-2008, 13:27
TOPO map? Who wants to bother with that? Is it on my GPS?


you can add the number of contour lines up and multiply by the contour interval to determine elevation gain.

Eh? Say again? Math? I'm too busy figuring out how many miles per day I need to reach Katahdin by October 15, thanks.

Bearpaw
01-19-2008, 13:57
My old signature was "The Dirt Don't Lie". It was a saying that meant that while trails, roads, buildings, forested areas and so forth may be wrong on a topo, the contour lines are generally quite accurate since it's usually just too difficult for people to reshape the side of a mountain enough to alter a 20-foot contour interval.....

Learn to read contours maps folks. You'll never be lost again, though you can still be confused every once in a while.;)

mountain squid
01-19-2008, 15:03
Using the profile to determine elevation gain/loss is secondary to me. http://www.freesmileys.org/smileys/think004.gifI use the profile primarily to determine distance. If I am standing on Watauga Dam Rd and plan to hike to Vandeventer Shelter, looking at the profile quickly tells me it is about 4.5 miles to the shelter. Otherwise, I'd have to break out a piece of string, place it on the legend scale and then 'snake' it on the trail on the map to determine distance. The profile makes it soooo much easier...

See you on the trail,
mt squid

kayak karl
01-19-2008, 15:16
TOPO map? Who wants to bother with that? Is it on my GPS?



Eh? Say again? Math? I'm too busy figuring out how many miles per day I need to reach Katahdin by October 15, thanks.
some of us hike trails without blazes. i haven't had my batteries die in my TOPO yet:D:D

Alligator
01-19-2008, 15:48
I use the profile map to adjust daily mileage, more big climbs=less miles. While I can read the contour lines, it's a lot faster just to look at the profile.

10-K
01-19-2008, 16:11
I've known what contour lines were and "sorta" how to read them for years. However, I'm taking an Outdoor Survival course at the community college this semester and we're spending about a third of the course learning how to read topo maps and how to navigate with a map and compass.

I'll probably never need to use these skills hiking on the AT but it's still something I find very interesting and worthwhile learning. Then again I'm taking a first aid course at the Red Cross too - filling my head with stuff I'll probably ever need.

Thanks
Thomas

Yahtzee
01-19-2008, 16:50
Actually, being able to read contour lines makes the maps sooo much more useful. Depending on your comfortability level with contours, they can read so much truer than an elevation profile.

Toolshed
01-19-2008, 16:53
I appreciate profiles on my AT maps. I look at them as another planning tool when determining mileage, stops, water and the like. I really like as MSquid said, you get a quick mileage summary rather than snaking along (I use the edge of piece of paper and spin it around as I follow the trail curves and turns, marking each spin on the edge and moving the paper forward. When I am finished, I simply measure the length of paper I used and I have total distance).

I don;t have my maps in front of me, but does anyone know what the exaggeration is? I know some of my ADK maps have V/E of close to 5, but I never really checked my AT maps.

I don't know about the rest but I can usually look at a topo map and kinda "see it" in 3D when I focus on various sections.

Pedaling Fool
01-19-2008, 17:00
...I don;t have my maps in front of me, but does anyone know what the exaggeration is? I know some of my ADK maps have V/E of close to 5, but I never really checked my AT maps...
Since they're not standardized they vary, but most have a V/E of 5.28. Which reminds me, how about that profile map on the National Geo map, now that's about as useless as can be.

Jack Tarlin
01-19-2008, 17:05
Actually, over the years, I've found the profiles to be very useful, and a lot more accurate than most people seem to think.

The best thing about them is that they'll give you a pretty good idea of what your upcoming hiking day will be like. For example, I like to get the big steep climbs out of the way early in the morning, when I'm fresh, before I'm too tired, and before it gets too hot out. I HATE doing a monster climb late in the PM. The profiles are invaluable as far as telling you what lies just ahead of you......if you want to finish the day with a big climb, you can, or, with the fore-knowledge, you might elect to wait til next morning.

Also, the profiles will tell you when it's wise to go for a big mileage day and when it'd be best to wait for a day or two. I can't tell you how many times I've seen people talking big at breakfast-time about the enormous days they are planning.......and then I see them again, exhausted, 13 miles later because they picked the wrong day to go for the monster miles. A study of the maps and profiles can prevent this, and can help youmake wiser decisions, especially if you're thinking about going for a big-mile day. Also, they'll give you a rough idea of how many hours it'll take to cover a particular stretch, which can be useful, if you have to make a town, road crossing, etc. Having a better idea of the terrain that lies ahead really gives one a better idea of how long it'll take to cover that particular stretch of Trail.

One more thing.....when the weather's good, and you want to get up high to catch a great sunset, meteor shower, or whatever, the profiles will help you find a good spot.

Also, some folks like to do some sections in a different direction. The profiles will tell you such things like the stretch heading Southbound into Hot Springs or Damascus is a lot easier than that same stretch going North. Likewise, if you're going over Roan Mountain, it's easier to go from Carver's Gap and proceed South, as you'll have a short and sharp climb with a long descent, rather than a half-day summit climb. It's much easier heading back to wards Erwin as a southbounder. This sort of info is especially helpful to section hikers, but it's useful to anyone, really, especialy if you're planning to slackpack a section of the Trail, or if you're nursing an injury. Knowing what the terrain ahead of you is like gives you different options.

The single biggest advantage to using the profiles is that it'll give one a reasonably accurate mental picture of the miles that lie in front of you and what they are likely to be like. I realsize that some hikers would rather not know.

But I ALWAYS want to know,as it helps me make more informed decisions about my daily plans; my mileage; how long it'll likely take to cover a particular stetch of Trail; where I might want to camp, etc.

When I hear people say that the profiles are useless, well, I really have to disagree.

Grumpy Ol' Pops
01-19-2008, 17:15
Those profiles indicate more than just elevation changes. If you get a copy of the USGS map "directions" you'll see that the contour lines do, indeed, indicate elevation change, but it's equally important to realize that they also are a graphic representation of the effort required to ascend or descend mountains, the directions in which rivers run, level spots (for all the stealth campers out there), and other necessary information. For anyone who hikes the deserts, they indicate arroyos that, in a flash rainstorm, will flood quickly and possibly trap a hiker against steep, unclimbable canyon walls. These indications are not in words, but are indicated by the closeness of contour lines (wall steepness) as well as "pointed" contour lines away from or toward your destination.

Kirby
01-19-2008, 17:19
A lot of the AT maps I have seen have a V/E of 5.28. The Smokies profile map, just by looking at it, seems absolutely useless.

Kirby

mudhead
01-19-2008, 20:51
course learning how to read topo maps and how to navigate with a map and compass.

taking a first aid course at the Red Cross too
Thomas

I am certain you will never regret taking these courses.

Alligator
01-20-2008, 00:56
That 5.28 is contrived so that 1000ft in elevation equals 1 mile horizontal on the profile. It's just kind of convenient.

Cindy from Indy
01-20-2008, 09:19
When I go to the ATC website to buy the maps, what am I looking for??? I don't want to buy every states guidebook, I just want the maps.....

Kirby
01-20-2008, 09:44
https://www.atctrailstore.org/catalog/iteminfo.cfm?itemid=190&compid=1

Kirby

Cindy from Indy
01-20-2008, 15:26
Thanks Kirby........... :)

dessertrat
01-20-2008, 15:41
I like them. They help me plan. However, you have to be careful not to get suckered by a fairly flat profile into thinking it will necessarily be easy-- there are some hard sections of trail that don't show much change on a topo map or elavation profile.

Kirby
01-20-2008, 15:57
I like them. They help me plan. However, you have to be careful not to get suckered by a fairly flat profile into thinking it will necessarily be easy-- there are some hard sections of trail that don't show much change on a topo map or elavation profile.

Exactly, the first 15 miles of the 100 mile wilderness are, by profile standards, "flat", those were the worst 15 miles of the whole trips. Lot and lots of puds. Just realize when something is flat on the profile map, that is just telling you that there are no major mountains, but there will be ups and downs, a lot.

Kirby

dessertrat
01-20-2008, 16:19
Exactly, the first 15 miles of the 100 mile wilderness are, by profile standards, "flat", those were the worst 15 miles of the whole trips. Lot and lots of puds. Just realize when something is flat on the profile map, that is just telling you that there are no major mountains, but there will be ups and downs, a lot.

Kirby

Kirby, that is exactly one of the places I was thinking of! There is a great hill in that section, though, where you get almost the same view as the one you get from the barren ledges, but lower down-- do you know the one I mean?

Kirby
01-20-2008, 16:28
Kirby, that is exactly one of the places I was thinking of! There is a great hill in that section, though, where you get almost the same view as the one you get from the barren ledges, but lower down-- do you know the one I mean?

I don't have my maps in front of me, so I am unsure. I don't recall having any good views in the first 15 miles, I just remember that it was miserable, and that I was beat at the end of the day.

Kirby

WalkinHome
01-21-2008, 15:59
I have to chime in here because I cannot resist giving Kirby a jab. Map 3 in Maine starting in Monson clearly shows a bunch of pud's. I'm sorry but that ain't flat. You want to see flat, go to Map 1 - there is a bunch of flat or almost flat there and in Maine, that is as flat as the AT gets. Now class, put Map 1 and Map 3 over one another and tell me which profile has flat in it LOL. If you have been on the AT for more than 30 minutes you know you will be going up and down all day. When in doubt, look around, find the highest point and go up. That is probably where you are heading. All of you have a great and safe hike and take all the profiles with a grain of salt LO

BR360
01-21-2008, 16:18
The map is not the territory. The profile is not the reality of elevation change.

Maps and profiles are scaled analogs for the reality of the landforms and terrain that the trail passes over. They cannot represent all the reality (they do not refer to the difficulty of the treadway for instance, whether it has roots, rocks, etc.) of the path. Got to be careful "interpreting" topo maps and profiles.

They are useful. As an outdoor educator I've taught several hundred people to navigate with topo maps and compass. While everyone can learn it, some are much more natural at it than others.

Some are intrigued with the mental "picture" that a topo can provide :-?, others never could relate the picture of the map and the physical terrain without extreme effort:eek:.

Personally, I love maps and profiles. They give me information I find valuable. I don't always pay attention to it, but when I am "confused" or tired, I am glad to have it. (That's also why I hike with a GPS---tho I would not carry one on a thru-hike due to the weight.)

ki0eh
01-21-2008, 16:25
All maps lie, a map must lie to be useful. (Round earth, flat surface, you know...)

USGS 7.5' quad maps do lie too. In many places in Central PA at least, these show trails where there is absolutely no way a trail could ever have gone where the map says. There was a lot of hand work that went into these and some of that must have been on Monday morning before coffee or Friday afternoon.

7.5' map derived products lie too, such as computerized elevation matrices taken from interpolating the contour lines that might have been drawn on Friday afternoon.

Elevation figures on a GPS lie, due to extremely disfavorable trigonometry of elevation differences vs. positional differences wrt orbiting satellites. The old analog procedure of altimetry is still more accurate.

Soon for PA at least, we will supposedly have radar derived elevation data available, finally liberating us from what someone thought the terrain looked like after looking at too many stereopairs in 1946.

Maybe then I'll venture to create a profile of a footpath... without getting roasted.

Toolshed
01-21-2008, 18:52
....

Elevation figures on a GPS lie

I get a kick out of driving up the Northern Extension and through the tunnel under the AT. My GPS map keeps saying I am climbing over the ridge my sat elevation says I am not. a real conundrum:cool:

Kirby
01-21-2008, 19:23
I have to chime in here because I cannot resist giving Kirby a jab. Map 3 in Maine starting in Monson clearly shows a bunch of pud's. I'm sorry but that ain't flat. You want to see flat, go to Map 1 - there is a bunch of flat or almost flat there and in Maine, that is as flat as the AT gets. Now class, put Map 1 and Map 3 over one another and tell me which profile has flat in it LOL. If you have been on the AT for more than 30 minutes you know you will be going up and down all day. When in doubt, look around, find the highest point and go up. That is probably where you are heading. All of you have a great and safe hike and take all the profiles with a grain of salt LO

There were a lot more PUDS in the first 15 miles than that stupid map says. (Nice to hear from you Ray, great presentation).

Attention:
The Maine AT is never flat. Thank you.

I'm gonna go lick my wounds now,
Kirby

RITBlake
01-22-2008, 10:56
Attention:
The Maine AT is never flat. Thank you.


Kirby

I'm guessing you haven't walked the length of the AT in Maine then....