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1. Read and translate the text:

Topographic maps

Topographic maps are used for a wide variety of applications, from camping, canoeing, hunting and fishing, to urban planning, resource development and surveying.

Why? Because they accurately represent, to scale, the earth's features on a two dimensional surface; that is to say, every feature shown on a map is where it actually is on the earth's surface.

  A topographic map is a detailed and accurate graphic representation of cultural and natural features on the ground.    A topographic map identifies numerous cultural and natural ground features, which can be divided into the following categories:

• culture: roads, buildings, urban development, boundaries, railways, power transmission lines;

• water: lakes, rivers, streams, swamps, rapids;

• relief: mountains, valleys, slopes, depressions;

• vegetation: wooded and cleared areas, vineyards and orchards;

• toponymy: place names, water feature names, highway names.

Seven colours can be found on a map, each relating to different types of features.

• Black shows cultural features such as buildings, railways and power transmission lines. It is also used to show geographical names (toponymy), certain symbols, geographic coordinates, precise elevations, border information and surround information.

• Red is used for paved roads, highway numbers, interchange exit numbers, certain symbols as well as for names of major transportation routes. A red tint is used to show urban development.

• Orange indicates unpaved roads and unclassified roads and streets.

• Brown shows contour lines, contour elevations, spot elevations, sand and eskers. Contour lines connect a series of points of equal elevation and are used to illustrate relief on a map. For example, numerous contour lines that are close to one another show hilly or mountainous terrain; when far apart, they indicate a gentler slope. Each contour is a line of equal elevation; therefore, contours never cross. To help the user determine elevations, index contours are wider.

• Blue represents water features, such as lakes, streams, falls, rapids, swamps and marshes. The names of water bodies and water courses are also shown in blue.

• Green is used for wooded areas, orchards and vineyards.

• Grey is used on the back of the map to indicate the different symbols and a glossary of terms and abbreviations.

• Purple can be used to show added information (update) over the original map detail.

Since a map is a reduced representation of the real world, map symbols are used to represent real objects. Without symbols, we wouldn't have maps.

Both shapes and colours can be used for symbols on maps. A small circle may mean a point of interest, with a brown circle meaning recreation, red circle meaning services, and green circle meaning rest stop. Colours may cover larger areas of a map, such as green representing forested land and blue representing waterways.

To ensure that a person can correctly read a map, a map legend is a key to all the symbols used on a map. It is like a dictionary so you can understand the meaning of what the map represents.

Here are some common symbols:

Topographic maps also show both a geographic grid (latitude/longitude) and a UTM grid allowing the user to determine precise positions.    Scale refers to the relationship between distance on a map and the corresponding distance on the ground. At a scale of 1:50 000 for example, one unit of measure on the map represents 50 000 equivalent units of measure on the ground. Medium-scale maps (e.g. 1:50 000) cover smaller areas in greater detail, whereas smaller-scale maps (e.g. 1:250 000) cover large areas in less detail.

2. Answer the questions:

1. What are topographic maps used for?

2. Why are topographic maps used in a variety of applications?

3. What is a topographic map?

4. What does this map type identify?

5. How can natural and cultural features be divided?

6. What colours can be found on topographic maps?

7. What are contour lines used for?

8. What do different colours on maps mean?

9. What is used for representation of real objects on maps?

10. What can symbols of different shapes and colours mean?

11. What is the difference between medium-scale and small-scale maps?

3. Decide whether the statements are true or false:

1. Topographic maps are used only for urban planning.

2. A topographic map is a detailed and accurate graphic representation of cultural and natural features on the ground.

3. Seven colours can be found on a map, each relating to different types of features.

4. Black indicates unpaved roads and unclassified roads and streets.

5. Brown shows contour lines, contour elevations, spot elevations, sand and eskers.

6. Contour lines are used to illustrate density and growth of population on a map.

7. Water features are shown in grey.

8. A map legend is a key to all the symbols used on a map.

9. Topographic maps show both a geographic grid (latitude/longitude) and a UTM grid allowing the user to determine precise positions. 

10. Scale doesn’t refer to the relationship between distance on a map and the corresponding distance on the ground.

4. Fill in the tables with topographic symbols:

5. Look at the topographic terms often used and find their definitions:

Classified roads, contour lines, elevation, mean sea level, projection, relief, topography, unclassified roads, UTM grid

• a square grid system based on the transverse Mercator projection, depicted on maps. It can be used to locate the position of features on the map accurately by distance or direction.

• geometric representation of the curved surface of the earth on a flat sheet of paper.

• lines on the map connecting points of equal elevation above mean sea level; using contour lines, relief features can be profiled into a three-dimensional perspective.

• roads for which surface type, width and use are identified.

• roads for which the surface is unidentified.

• surface features both natural and cultural, collectively depicted on topographic maps.

• the average height of the surface of the sea for all stages of tide, used as a reference surface from which elevations are measured.

• the physical configuration of the earth's surface, depicted on a topographic map by contour lines and spot heights.

• vertical distance from a datum (usually mean sea level) to a point or object on the earth's surface.