1. The Topographic Map

2. What Does Earth Really Look Like?
A map is a representation of the features of a physical body such as Earth but is drawn on a flat surface.
The Greeks thought of Earth as a sphere almost 2, years before Columbus sailed in 1492.
Around 240 BCE, Greek mathematician Eratosthenes calculated the circumference of the Earth. His calculation was wrong by only 6,250 km.

3. Each type of map shows different things
Map Basics….
Each type of map shows different things
People who make maps are called cartographers.
In order to read a map, familiarize yourself with the map’s scale, symbols, and if needed contour information

4. Information Shown on Maps
Maps should have BOLTS
Border
Orientation: a compass rose indicating Direction
Legend
Title
Scale.
Unfortunately, not all maps have all this information. The more of this information a map has, the more reliable the map is.

5. Features of Topographic Maps
TOPOGRAPHY (the shape of the land):
The topography of the land is determined by how uneven the lands surface (hills, mountains, valleys\ and slight depressions (dips) in the land surface.

6. Uses for Topographic Maps
Topographic maps have many uses in science, engineering, business, government, and everyday life for recreational purposes (hiking, canoe trips etc..

7. What do topographic maps show?
A topographic map is a map that shows surface features, or topography, of the Earth.
Topographic maps also show
- physical shape of the land
- natural elements: vegetation, water
- human made features- buildings, roads...
Topographic maps also show elevation
(flat areas hills, valleys mountains).

8. Reading a Topographic Map
Topographic maps use symbols to represent parts of the Earth’s surface.
Colors are also used to represent natural or man made features.
For example, cities and towns are pink, bodies of water are blue, and wooded areas are green.

9. LAND NAVIGATION WITH MAP AND COMPASS
PART 1 Basic Land Navigation
LAND NAVIGATION WITH MAP
AND COMPASS

10. THE TOPOGRPHIC MAP Colours and Symbols
PART 1 Basic Land Navigation
THE TOPOGRPHIC MAP
Colours and Symbols
- A topographic map is a drawing that represents the natural and man made elements of a given area.
- Colours, lines and symbols are used to represent things like mountains, streams, buildings, forests etc...
- these symbols present the natural and man made elements of a given area.
- However, the finest maps available are worthless unless the map user knows how to read them.

11. Symbols
Symbols are used to represent the natural and man-made features of the earth.
Contour Lines show relief (up and down) and elevation (height); they indicate variations in terrain features and heights of natural features.

12. Elements of the Topographic Map
USGS Topographic Map Symbol Website
<click here>

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Map Symbols
Topographic maps usually have a separate sheet with an explanation of map symbols. There is no room on the map for all the symbols
Sample page from USGS Topo Map Symbol Pamphlet

14. Topographic Contour Lines connects points of equal elevation
Rules:
Lines never cross
They are brown
Lines “V” upstream
Lines show changes in elevation
Each contour interval here is 20 metres

15. TOPOGRAPHIC MAP DESCRIPTION
PART 1 Basic Land Navigation
TOPOGRAPHIC MAP DESCRIPTION
Five basic colors are used for Topographic Maps.
Brown (Contour Lines: shows elevation)
Black (Man Made Features: Buidlings, Roads, Trails)
Blue (Water Features: lakes, rivers)
Green (Vegetation: forests, other)
Red (Highway and Land Grids)
Three minor colors
Pink (Built up area, civilization)
Purple (Updated Map Information)
White: no forests, might be farmland, meadows etc…

16. PART 1 Basic Land Navigation
Map Symbols
Symbols are used to represent the natural and man-made features of the earth.
It is a map language that is simple to read and understand. BUT you must first know what the map symbols represent, in order to understand, read and speak map language to others.
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17. Map Symbols VEGETATION Woods Scrub Orchard Vineyard Mangrove
PART 1 Basic Land Navigation
Map Symbols
VEGETATION
Woods
Scrub
Orchard
Vineyard
Mangrove

18. SUBMERGED AREAS AND BOGS
PART 1 Basic Land Navigation
SUBMERGED AREAS AND BOGS
Marsh or swamp
Submerge marsh or swamp
Wood marsh or swamp
Submerge wood marsh or swamp
Rice field
Land subject to inundation

19. RIVERS, LAKES, AND CANALS
PART 1 Basic Land Navigation
Map Symbols
RIVERS, LAKES, AND CANALS
Intermittent stream
Perennial lake or pond
Perennial stream
Intermittent lake or pond
Dry lake
Intermittent river
Well or spring
Perennial river
Dam
Small falls; small rapids
Canal
Large falls; large rapids

20. MAN-MADE FEATURES and HIGHWAY & LAND GRIDS
PART 1 Basic Land Navigation
MAN-MADE FEATURES and HIGHWAY & LAND GRIDS
Map Symbols
Built-up Areas
Highway
Buildings
Land Grids
Road
School 12 13 14 15 16 17 18 19 20
Dirt Road
Church
Bridge
Airports
Foot Bridge
Landing Strip
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Cemetery
Trail
Mine
Power Lines
Gravel Pit
Railroad

21. Topo maps are “large scale” maps
PART 1 Basic Land Navigation
Topo maps are “large scale” maps 21
Topographic maps are “large” scale: That means that it has a large amount of detail but a small land area. (one or two towns…, roads, houses, lakes…) 1: or 1cm to .5 km
- A map of the world is “small” scale: Small amount of detail and large amount of land area (no houses, only major cities etc..) 1: or 1cm to 250 km

22. Large-scale
Small-scale

23. Finding Direction with a Topographic Map
Topographic maps are useless if you do not know which direction you are travelling in.
They must be used with a compass.
A compass is a tool that uses the natural magnetism of the Earth to show direction.
A compass needle points to the magnetic north pole.

24. Military Grid system
Lines of latitude and lines of longitude cross and form a grid system on globes and maps.
This grid system can be used to find locations on the Earth’s surface.
Topo maps do not use degrees…
they just number their own lines

25. Finding Locations on the Earth, continued
Topographic were invented by the military.
The grid system used is called the military grid system
The light blue lines on a topographic map do not represent latitude and longitude

26. Eastings and Northings
The lines that run north and south are called Eastings (run your finger east to find them)
The lines that run East and West are called Northings (run your finger north to find them.

27. Do a “RIGHT UP”…
To find a grid location on a topo map, you want to find the Easting and Northing line.
Go right then up with your finger…..
Create an “L” with the intersecting lines.
this is the box location eg: 4282
Think 42easting/82 northing

28. Can you see the faint squares (usually in blue).
On this map they are the faint doted lines
(not the dark red and black ones, those are roads).
Each square e is 1km square
Eastings are on the top or bottom of the map. Easting lines go up and down 08 09 10 11 12 74 73 72

29. Military Grid System Each grid measures 2cm square.
The scale is 1cm to .5 km
So each square in the grid represents 1km square in the real world
For a 6 digit reference, you would measure 2mm for every tenth…

30. Eastings and Northings…
The lines that run north and south are called Eastings (run your finger east to find them)
The lines that run East and West are called Northings (run your finger north to find them.

31. Elements of Elevation, continued
Contour Lines are lines that connect points of equal elevation. Topographic maps use contour lines to show elevation.
Contour Interval is the difference in elevation between one contour line and the next.
Relief is the difference in elevation between the highest and lowest points of the area being mapped. Relief is used to determine the contour interval of a map.

32. Contour Lines Elevation is indicated by contour lines.33
Contour Lines
Elevation is indicated by contour lines.
A contour line is a line of equal elevations.
All points on a contour line have the same height.
Contour Lines are brown
The contour interval is 20m.
800 feet
700 feet

33. Contour Lines 34
The elevation difference from one line to another is called the contour interval. On the map portion below the contour interval is 20 meters.
20 m elevation decrease
20 m elevation increase
20 m elevation increase

34. Steep or flat? If lines are close together that means that35
Steep or flat?
You can tell whether a region on a map is steep terrain (hill/mountain) or relatively flat (plain) by looking at contour lines.
HOW?
If lines are close together that means that
this part of the hill is steep.
If they are far apart, it means a gentle
slope

35. Steep or flat?
FLAT
Steep
0.5 mile distance

36. Elements of Elevation, continued
The spacing of contour lines indicate slope.
Contour lines that are close together show a steep slope.
Contour lines that are far apart show a gentle slope.
An index contour is a darker, heavier line that is usually every fifth line and that is labeled by elevation.

37. 38
Contours and Profiles
You can generate a profile of a landform from the contour lines on a topographic map.
Click on image
to see contours
develop
Simple contour map

38. 39
Bathymetric Maps
Maps of water depths are like topographic maps with contours. However, the contours are water depths, not elevations.