Land Navigation

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Land Navigation
Mazamas BCEP

• John Bartholomew
• jbartholomew_at_alum.mit.edu

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BCEP - Navigation Goals

• Discuss the Tools of the Trade (map, compass,
  altimeter, GPS)
• Understand map scale, symbols, contours, and the
  UTM coordinate system
• Basic overview of the compass (more compass use
  may be covered by your BCEP team leader)?
• Learn how not to get lost, and what to do if you
  are
• Some fun ways to practice navigation

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Why does BCEP concentrate on map skills, and less
on compass use?

• There are FIVE components of navigation
• Distance (How far is it from basecamp to the
  summit?)?
• Direction (The route to the summit is NW from
  camp.)?
• Elevation (Whats the elevation of basecamp?
  What is the elevation gain from basecamp to the
  summit?
• Terrain (Is the terrain well cross steep or
  flat? Do those contour lines show a gully or a
  ridge? Is the vegetation dense forest or open
  snow?)?
• Time (How long did it take to get from basecamp
  to the summit?)?

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Of these five components, a map can tell you four
of them!

• Maps tell you 1) Distance, 2) Elevation, 3)
  Terrain, and 4) Direction, in a general sort of
  way. (A watch tells you the time )?
•  
• A compass can only tell you more precise
  direction, such as, the lake where we will we
  will camp is 334 degrees from here.
•  
• A compass is normally used only when you need a
  more precise direction that the map cant give
  you.
• Note A map and compass are not always used
  together.

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Maps - Know Thy Terrain!

• What is a topo map?
• Symbols Legend
• Scale
• Coordinate systems
• Contour lines
• Declination

You are often able to navigate without a compass,
but without a map?!?
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What is a topo map, anyway?

• In the city, we use planimetric maps. They show
  manmade features, but not much of the underlying
  terrain.
• In the backcountry, we use topographic maps.
  These emphasize natural features (topography)
  over manmade objects.

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One way to represent a 3-D world Google Earth
Mt. Washington, OR (looking SE)
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Another way to represent a 3-D world Topographic
map, Mt. Washington
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Symbols Legend

• Refer to your maps legend (if it has one) to
  find what a given symbol means.
• While standards do exists, not all symbols or
  colors are alike on all maps.

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Map Scale

• A scale is a ratio. A 124,000 map means one
  inch on the map equals 24,000 inches on the
  ground (or about 2.5 inches 1 mile)?
• Map scale can be confusing! Large scale and
  Small scale mean the opposite of what you
  might think.
• The larger the second number, the larger the area
  shown on the map . . . but the smaller the scale.
  
• All of USA is mapped at 124,000 - a good level
  of detail for backcountry travel.

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Scale Large to Small
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Map Coordinate Systems

• Coordinate system a way to state the precise
  location of any point on earth, usually by
  stating two numbers.
• Topo maps typically have two systems printed on
  the margins 1) UTM and 2) Latitude/Longitude.
• Latitude/longitude (deg/min/sec decimal) is
  confusing and hard to use for most land
  navigation.
• UTM (Universal Transverse Mercator) is the
  preferred system for mountaineering. Here, the
  globe is divided into 1 km squares.

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UTM Coordinates Easting and Northing

• UTM coordinates are given in an easting and a
  northing.
• The green grids are 1 km on a side.
• Easting values increase as you move east.
  Northing values increase as you move north.

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Map Coordinate Systems UTM and Lat-Long,
example

• 597 821 is in 100-meter abbreviated format, as
  you'll often be navigating in a limited area.
• The full UTM coordinates (on a GPS for example)
  might be

10 H 0659733 mE 4282185 mN meaning in
Zone 10 H 0659733 meters E 4282185 meters
N within the zone
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Contour Lines

• Contour lines are how topo maps attempt to convey
  a 3-D world onto paper.
• Contour lines connect points of equal elevation.
• Topo maps have index contours in bold text and
  at regular intervals. These have a printed
  elevation.

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Contours and Terrain - Slope

• Contour lines indicate slope.
• Closely spaced lines show a steeper slope, widely
  spaced lines show a gentler slope.
• Contour lines printed on top of each other
  cliff!

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Contours and Terrain - Summit

• Many concentric circles indicate a summit.
• Fewer circles may only be a local summit or knoll.

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Contours and Terrain - Saddle

• Saddles head down on two sides and up on the
  other, hence the name.
• Often found on ridge lines.
• Saddles are often an important part of a climbing
  route.

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Contours and Terrain Tricky!

• Contours with dashes indicate a downward slope,
  or depression. (This is a rare feature, but you
  can find it.)?
• Often, spurs and valleys can look alike!
• Sometimes youll need to include other terrain
  information, like streams, to help tell them
  apart.

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Contours and Terrain Gully or Spur?

• A spurs U points downhill.

• A gullys V points uphill.

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Contours and Terrain Gullies
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Contours and Terrain Spurs
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Contours and Terrain - Drainages

• Other U shaped features are valleys and cirques.

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Contours and Terrain - Ridgelines

• A ridgeline with various summits/highpoints along
  it.

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Tools of the Trade

• Compass
• Altimeter
• GPS
• How to Take a Compass Bearing

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Compass the parts
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Dont buy these
lensatic compass inexpensive, takes forever for
needle to settle
specialty compass for orienteering, military,
etc.
simple base plate no built-in declination must
do it in your head
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The best compass for mountaineering Baseplate
compass with adj. declination

• Inexpensive (about 25)
• Light, durable
• Liquid bearing dampens needle jitter
• Adjustable declination is a VERY desirable
  feature!

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A fancier baseplate compass . .

• Additional features clinometer and sighting
  mirror.
• You need to learn how to use these features
• Expensive (50-60)?
• Nice if you already have it and know its use,
  but not the best first compass to buy.

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Using Your Compass Mirror
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Altimeters

• Work by measuring changes in atmospheric
  pressure.
• CALIBRATION is required for accuracy!
• Increasingly built into watches, GPS, etc.
• Not required gear for BCEP.

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Altimeter Tips

• Recalibrate your altimeter when you are at a
  known elevation (summit, lake, saddle, etc.)?
• Do this more often if the weather is unsettled.
• Encourage everyone on your team with an altimeter
  to do the same. If your altimeters are all as
  accurate as possible, making key route finding
  decisions based on elevation is much easier.

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GPSGlobal Positioning System

• They primarily give you grid position (lat long
  or UTM), altitude, and distance/direction between
  stored points.
• Many features on newer models (maps, routes, )?
• Tree cover and cold can cause problems.
• Always used WITH a map and compass, not by itself!

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Taking a Compass Bearing

• Bearing should always be from true north (not
  magnetic north)?
• They are measured clockwise from 0 degrees north.

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Taking a Compass Bearing

• 1 Face toward your objective. Hold compass at
  your navel.
• 2 Rotate the housing until the magnetic needle
  aligns with the orienting arrow.
• 3 Read the bearing.

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Declination

• Maps are oriented to the north pole, aka true
  north.
• Compass needles point to magnetic north. These
  two places are NOT the same!
• Declination is the difference between the
  physical north pole and magnetic north.
• This varies a lot with location and (a little
  bit) with time.

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Declination changes with your location
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Declination Dealing with it

• The declination is usually a diagram printed on
  maps.
• In the Pacific NW, declination is about 18 deg.
  East, Portland it's about 16 degrees.
• Spend the extra 10 and get a compass with
  adjustable declination! Once its set, the
  needle still points to magnetic north, but the
  compass will point to the true north pole.
• Some nav. books tell you to measure to magnetic
  north, then add / subtract to get the true north
  bearing. Dont make a habit of this - even
  simple arithmetic in the backcountry is asking
  for trouble!

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Declination - Example

• Set declination on your compass
• Line up magnetic north with the red outline arrow
• Now line up north on your map with north on your
  compass dial.

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Getting Lostand Un-lost Again

• Avoiding problems to begin with
• What to do if you are lost
• Parallel errors

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Staying Un-lost - 1

• Avoid problems by verifying your location often
  (staying in touch with the map/thumbing the
  map)?
• Always plan a safety bearing in advance to exit
  an area (general direction to a known feature,
  like a road, river, etc.)?
• Be sure all members of your party are acquainted
  with the intended route, even if this is just a
  quick review at the trailhead.

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Staying Un-lost - 2

• Use more than one navigator per group. Encourage
  your climbing team to voice any suspicions they
  may have that the route may be incorrect.
• Carry spare compass, altimeter, GPS, map...
• Always use a waterproof map case.
• If you're on a trip with more serious route
  finding challenges, consider making a formal
  route card, with enough detail and decision
  points to make you confident of successful
  navigation.

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Staying Un-lost - 3

• If you're returning along the same path, mark the
  return route with a few meters of brightly
  colored plastic surveyors tape. (Be sure and
  collect it when you hike out.)
• Don't allow your climbing team to become widely
  separated its a huge waste of time to find a
  lost member.
• Practice navigation skills whenever possible!

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Navigating by Features

• Collecting Features

• Catching Features

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Aiming Off

• Useful for avoiding time searching for your goal
  along a linear feature, like a trail, stream or
  road.
• Intentionally aim off to one side, so youre sure
  of which way to turn at the feature.

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What to do if you are lost . .

• STOP! Where were you last when you were sure of
  where you were?
• Back track there resume course.
• Spend time fixing your location correct course.
  (ex back bearings).
• Worst case stay put.
• Searchers look for clues, not people. Leave lots
  of clues (deliberate footprints, lined up rocks,
  written notes, scratched arrows in dirt)?

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The Parallel Error

• Perhaps the hardest error to detect everything
  looks right, but youre in the wrong place!

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Navigation - Fun and Games

• Map and compass practice sessions
• Geocaching
• Orienteering

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Practice Sessions

• A permanent map and compass practice course is
  now established at Mt. Tabor.
• Designed specifically for BCEP navigation
  practice.
• Try the course with your BCEP team or on your
  own.
• Map and field exercises are available on the
  Mazamas web under Resources.

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Geocaching

• Web site www.geocaching.com
• Requires a GPS unit
• Search for hidden caches of trinkets and a
  logbook to sign

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The Sport of Orienteering

• Navigation racing - map compass only
• Worldwide sport, over 100 years old
• Practice in the small - for the real thing in the
  large
• Local club Web site www.croc.org
• National site www.us.orienteering.org

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Thanks - and good navigating!