| GPS:
Global Positioning Systems by
Chuck
Holton
One of the great joys of a trip to the Boundary Waters is the ability
to lose oneself in the limitless expanse of clear water and blue sky.
Few people, however, do so with the intention of staying lost. The
labyrinth of waterways that make up the canoe country can sometimes
confuse even the best of navigators since, after awhile, every shoreline
seems to look the same. Many people have experienced the anxious feeling
of looking for a portage that just isn't there, taking a wrong turn and
ending up in a different lake than they had planned, or having to
backtrack to find where they got off course. Some would philosophically
assert that this is all part of the boundary waters experience, and it
is, but as we discovered on a recent six day outing, knowing exactly
where you are isn't necessarily a bad thing. It can mean less time
paddling and more time for fishing, relaxing, or exploring.
The newest generation of Global Positioning Systems offers canoeists
the ability to increase the enjoyment and safety of a backcountry trip,
as well as allowing increased flexibility on which route to take. In
addition, a GPS can provide an exact record of the route taken and other
pertinent data after the trip that will do far more than answer the age
old question: ''Where am I?''
If you're not familiar with the Global Positioning System, it
consists of a constellation of satellites that the U.S. Military began
putting into orbit around 1990. There are now more than 24 satellites
active. The system continues to be funded and controlled by the U.S.
Department of Defense, and the Russian Federation is working on a system
of their own that will also be made available for civilian use. Put
simply, each satellite continuously broadcasts its position back to
earth with a coded signal that can be processed by a GPS Receiver on the
ground.
GPS receivers have a variety of applications. Models are available
for boats, aircraft and automobiles, as well as for scientific and
surveying purposes, but this article will deal exclusively with the
handheld models best suited for backcountry travel.
A handheld GPS receiver picks up signals from at least four
navigation satellites and uses those signals to compute it's own
position, speed, altitude, and the exact time. From this data most units
can calculate sunrise and sunset data, save waypoints and tracks, and
give estimated time of arrival, among other things.
Until recently, using a GPS took an exceptional understanding of
arcane navigational terms such as cross track error and velocity made
good. The user had to have a working knowledge of map datums such as the
Universal Transverse Mercator Projection, as well as a strong back for
all of the batteries that a GPS unit would consume on a weeklong outing.
Fortunately, the newest generation of handheld GPS receivers is small
enough to fit in a jeans pocket and intuitive enough for my mother to
use and understand.
It's important to point out that a GPS is only a navigational aid!
Owning a GPS does not mean you can throw away all of your paper maps.
Also, if you have no clue how to read a map, a GPS won't do you much
good either, unless someone else sets it up for you. As GPS systems get
better and more user friendly, however, it's not difficult to imagine a
day when outfitters will rent you a handheld receiver as a "virtual
guide." With topographic maps of the area and your trip route
already programmed in, all you would have to do is follow the directions
on the unit to get to your campsite, or a good place to catch trophy
walleye, or to find that overgrown portage that from the water looks
more like a beaver run than a trail. Because of the nature of electronic
gadgets, of course, it would never be prudent to enter the wilderness
without map and compass as backup.
Although there are at least ten different companies putting their
names on nearly fifty handheld GPS units these days, all GPS receivers
on the market can be divided into two categories: Those that show a map
on the unit's display, called ''Mapping receivers'', and those that
don't (someone stayed up all night thinking of this) called
''Non-mapping receivers''. At the low end of the GPS price range are the
non-mapping units that show your location as a grid coordinate. One of
these will suffice as a navigational aid (emphasis on the word ''aid'')
in the canoe country only if you are proficient enough to correlate a
grid coordinate to a position on a paper map. These units are best at
telling you where you've BEEN, and how to get BACK, it's more difficult
to get them to tell you where you are going and when you'll get there.
One of these units would do you very little good if a moose ate your
map. Some of them have extras like altimeters and digital compasses
built into them. If this sounds like too much trouble, you probably want
to opt for a unit that shows you a map of where you are, and allows you
to zoom in and out to find where you want to be.
Keep in mind that all handheld GPS units on the market today will
only show you how to get to your destination in a STRAIGHT LINE. This
isn't necessarily a bad thing, because it can help you determine the
shortest distance across a large lake. It can be misleading, however, if
you are following a circuitous route. This is another point in favor of
mapping receivers. If you plot a course to your intended campsite and
there's a large landmass with a 300-rod portage between you and your
destination, a mapping receiver will make it more immediately apparent,
and make it easier to find an alternate route.
Another feature common to virtually all handheld GPS units is the
non-color screen. While there are a few with color screens, they tend to
be units that you'd more likely carry in a car than a canoe. I'm sure
that someday all GPS units will have color screens, but for now you'll
most likely have to make do with a monochrome one. I'm not sure the
advantage of color would justify the additional cost anyway.
An
important note from the DUH! department: if you were buying a GPS for
the purpose of navigating around the Boundary ''Waters'', it would be a
good idea to get one that floats and is watertight. Not all are. Weight
and battery life are also key features: I once owned a nifty GPS unit
that would send and receive email from anywhere in the world. The
problem was that it was about the size of a World War II field telephone
and it had a proprietary rechargeable battery. It would last for a
couple of days in the woods and then the battery would die, and I'd be
stuck until we got back to civilization to recharge it. Most handheld
units these days last from 8 to 24 hours on a set of either two or four
AA batteries.
In my opinion, the Garmin eTrex Vista is probably the best all around
handheld unit on the market today for the wilderness enthusiast. The
eTrex Vista combines a basemap of North and South America, with a
barometric altimeter and electronic compass. The Vista also boasts an
internal memory capacity of 24 megabytes, which allows it to accept
downloaded mapping data from GARMIN's MapSourceR CD-ROMs. Its only
drawback for canoeists is that while the unit is waterproof (to 1
meter), it does not float, so if you drop one into the lake be prepared
to dive in after it. The eTrex Vista goes for about $350 in a store, and
around $285 on auction sites such as Ebay. Detailed downloadable
topographic maps must be purchased separately.
The first handheld GPS receiver that I owned was a Magellan 2000xl.
At the time, it was one of the best units available. It would store
waypoints and take me right to any grid coordinate I programmed into it,
providing I used the right map datum and could accurately read the
latitude and longitude off of a paper map. It ate four AA batteries in
about 8 hours. I loved it, and took it everywhere. After two years,
though, I came to the realization that the newer generation units had
much more to offer. Being the sentimental guy that I am, however, I
quickly sold it and acquired a Garmin eMap GPS receiver on E-bay. I also
invested in topographic software from Garmin's MapsourceR division. The
eMap's big advantage is that I can upload maps from my computer onto the
unit and it will display my position in real time right on the unit's
display screen, not as a coordinate, but as a point on the virtual map.
The unit only weighs six ounces, and my one year old son can't figure
out if it's a mobile phone or a TV Remote, which gives you an idea on
its size. It will also go for more than twelve hours on a good set of
AA's. When driving on the freeway, the eMap tells me what exit is coming
up, and which services are available at that exit. I can keep track of
mileage and the real time speed is more accurate than the speedometer in
my Suburban.
Some friends and I recently spent a glorious six days in the Boundary
Waters, starting from Saganaga Lake and making a loop around through
South Knife Lake and back through Seagull Lake. I got designated ''trip
navigator'' because, besides having an unnatural love of maps, I was
doing the designating.
Several months before the trip, we made reservations with our
outfitters, and ordered some maps from them. The manager there
recommended the route mentioned above as a ''moderate''trip for eight
first timers. We mapped out our expected route, then I plotted it on
theMapsource 1:100,000 topographic maps on my computer. From there I
downloaded our planned course to the GPS receiver, complete with the
topo maps of that area.
When it came time for the trip, we met in Minneapolis, the eight of
us converging from five different states. We piled into the Suburban
with Bongo, my Jack Russell Terrier, and headed north toward Grand
Marais.
On the way there, the E-map helped us find our way out of the
Minneapolis airport, then find I-35 North. It even told us what
restaurants we'd find at upcoming exits. When we arrived in Grand
Marais, it helped us find the right turnoff for the Gunflint Trail.
The next morning, we drew our canoes and other equipment, and then
headed north for the end of the Gunflint trail, where a pre-arranged
boat was waiting to give us a ride to American point. The topographic
maps on the eMap made the ride more interesting by allowing me to keep
track of exactly where we were during the ride, even giving me the names
of the islands that we passed. According to the unit, we averaged 14.1
miles per hour for the 7.5-mile one-way trip to American Point.
From there we put our canoes in the water and headed southwest toward
Monument portage. As we neared the portage it was interesting to know
exactly how close we were to the border of Canada, which runs down the
middle of the lake. When one of the canoes in our group strayed north a
bit, the GPS showed that they had crossed the border. ''Hey, get out of
Canada you two!'' I yelled to them, ''Before the Mounties come for
you!''
Sitting
in the rear of the canoe, I placed the eMap on my pack in front of me
where I could see it. I tied it to my person with a length of parachute
cord in case we hit a wave or something and it fell out of the boat. I
was a little worried about the fact that the eMap is NOT waterproof, and
had to be extra careful not to let it get wet. As it turned out, we had
smooth sailing for the entire trip, so it wasn't much of a problem.
Throughout the six days we spent paddling, the GPS continued to prove
its worth. It helped me mark a spot where a favorite lure got snagged
while fishing so that I could go back diving for it after pitching camp
and changing into swim trunks. It helped us track into the wind and
maintain course on a long paddle across South Knife Lake, helping us
reach our campsite faster, which gave us more time to relax after a long
day of paddling. I figured out that 60 strokes of my paddle equal
roughly 1/10th of a mile on a calm day. The sunrise/sunset information
provided by the eMap made sure I knew when to get up in time to catch a
beautiful sunrise on film. The bathymetric (underwater topography) data
it provided helped us find submerged rock piles to fish on. We always
knew how far we were from the next portage, though it didn't make
executing them any easier. It even enabled us to help another group of
paddlers find an overgrown portage that they had been unable to find. It
kept a track in memory everywhere we went, which made plotting our exact
course when we got back as easy as downloading that track to my laptop.
We traveled exactly 45.1 miles. Our average speed on the water was 3.5
miles per hour, with a top speed of 17 mph as we naively shot through a
rapids that we probably should have portaged around.
We were mentioning all of this to our outfitters when we finished the
trip. They wondered if it wouldn't be profitable to have a few GPS units
for rent in the shop, and everyone in our group agreed that the eMap was
definitely worth having along with us. Some folks that I've talked to
since have expressed reservations about the units, wondering if they're
really worth the extra weight. I'd assert that while a GPS is not
necessarily essential equipment, it did make the trip more interesting
and enjoyable, and for less than a pound of extra weight, including
batteries, it was definitely worth it.
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