CHAPTER 3

GEOGRAPHICAL SKILLS AND INVESTIGATIONS

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CHAPTER 3 GEOGRAPHICAL SKILLS AND INVESTIGATIONS

In this Chapter you will explore three key topics:

• Topographical map reading skills• Geographical data and techniques• Geographical investigations

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Your tourist friend is lost. He is currently at City Hall MRT Station, and he needs to get to Esplanade Theatre.

He gives you a call and ask for directions. Both you and your tourist friend have a copy of this map. How would you guide him to his destination?

Reading topographical maps

• Developing topographical map reading skills allows you to:- navigate to places- be conscious of the environment- understand how the environment is being

presented and (re)presented.

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Reading topographical maps

Reading grid references

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• They are used to identify locations.

• Always read the eastings (x-axis, vertical lines) then the northings (y-axis, horizontal lines)

• They can be: - 4 digit grid references

(xxyy): identify an area OR- 6 digit grid references (xxx1yyy1): identify a point

x1 and y1 are derived by sub- dividing the northings and eastings into 10 segments

Area: 0736

Point: 088376

Reading directions: Compass directions

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• They are used to describe the location of one geographic feature from another.

• Note that 4, 8 and 16 cardinal points can be used to provide a more precise location.

• When identifying direction, take note of the word ‘from’ which signifies the point you are taking direction from.

N

E

S

W

NE

SESW

NW

NNE

ENE

ESE

SSESSW

WSW

WNW

NNW

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• Compass bearings provide even more precise locations than compass directions.

Follow these steps when measuring compass bearing:1.Draw a straight line to join the two objects.2.Draw the north arrow on the object you are measuring ‘from’.3.Place the 0° of the protractor on the right side of the north arrow. Read clockwise to obtain the grid bearing.4.If the grid bearing is more than 180°, place the 0° of the protractor on the left side of the north arrow. Add 180° to the bearing measured by the protractor.

Reading directions: Compass bearings

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Interpreting scalesType of scale Desription

Representative fraction

• Written as a fraction (1/2,500) or Ratio (1:2,500)• No unit of measurement (can be used for any units

of measurement)

Linear scale • A visual representation using a straight line that is divided into equal parts.

• Used to represent actual distance on the map (e.g 2 cm represents 1 km)

Statement scale • A scale expressed in words (e.g 1 cm represents 1 km)

Measuring distances

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Straight-line distance1. Connect two points.2. Use a strip of paper to mark

out the distance between the points.

3. Place the strip of paper on the line scale.

4. Alternatively, use a calculator to convert the map distance into actual distance (i.e 1cm: 1km therefore 2.5cm=2.5 km)

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Curved distances1. Divide the curved distance

into various straight line segments.

2. Mark each location on the strip of paper until the whole length of the curved route is marked.

3. Place the strip of paper against the scale to convert into the actual distance.

4. Alternatively, use string to trace the curved distance, and then convert into actual distance using the scale.

Measuring distances

b. Describing relief and identifying features in topographical maps

• Describing the nature of relief• Identifying physical features and landforms• Calculating gradient• Interpreting map evidence• Interpreting map symbols• Interpreting human activities• Describing patterns and locations of vegetation, land

use, and transport and communication • Explaining the relationship between relief and land use

or transport and communication

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Describing the nature of relief

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Compare the two marked areas X and Y. What differences do you notice in these maps?

X

Y

Relief refers to the change in the height of a land surface, and is about height, shape, steepness, slope and form.

Relief can be deduced from the arrangement of contour lines and their contour intervals.

Contours are continuous lines joining points of the same height. As each contour is a line of equal height, contours never cross.

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Describing the nature of relief

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Describing the nature of relief

Match the contour patterns on the left with the landforms on the right.

Identifying physical features and landforms

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A B

C D

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E F

G H

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Description of landform Ans: Name of landform

• A highland more than 600 metres above sea level. • Have steep slopes indicated by closely spaced contour

lines.• A depression between two highlands. • Represented by v-shaped contour lines pointing towards

higher ground. • May have a river running through it• Low-lying land found near a river. • Generally flat and can be identified by the lack of contour

lines or widely spaced contours.• A highland with steep slopes and a flat summit.• Steep slopes are indicated by closely spaced contour

lines• A flat summit is shown by the absence of contour lines at

the summit.• Steep and near-vertical rock face. • It is indicated by closely spaced contour lines.

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Description of landform Ans: Name of landform

• A highland more than 600 metres above sea level. • Have steep slopes indicated by closely spaced contour

lines.

A Mountain

• Steep and near-vertical rock face. • It is indicated by closely spaced contour lines.

D Cliff

• A depression between two highlands. • represented by v-shaped contour lines pointing towards

higher ground. • may have a river running through it

B (River) Valley

• A low-lying land found near a river. • Generally flat and can be identified by the lack of contour

lines or widely spaced contours.

H Floodplain

• A highland with steep slopes and a flat summit.• Steep slopes are indicated by closely spaced contour

lines• A flat summit is shown by the absence of contour lines at

the summit.

C Plateau

Calculating gradient

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Gradient indicates the steepness of a slope. It is measured by dividing the height of the landwith a given horizontal distance. Gradient is expressed as a fraction or ratio. It is calculatedusing the formula:

Difference in height between two pointsHorizontal distance between two points

Follow these steps:1)Difference in height between two points: maximum height minus minimum height (using the contour values)2)Horizontal distance: measure the distance between the two points and convert into actual distance3)Divide results from (1) with (2). NOTE: both (1) and (2) must be in the same units i.e metres

Interpreting map symbols

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Symbols represent the actual features on the map. They are found in the key. They can be used to represent physical features and human activities. Some of the examples are seen on the left.

Interpreting human activities

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Map symbols help interpret the types of human activities present in an area. Humanactivities may be classified in broad categories:

Industries

Services and facilities

Agriculture

Interpreting human activities

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Transport and communication

Settlement pattern

Describing patterns and location of vegetation, land use, and transport

and communication

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Explaining the relationship between relief and land use or transport and communication

Maps and symbols• Base maps• Atlas• Topographical maps• Road maps• Sketch maps• Choropleth maps• Isoline maps• Dot maps• Maps with proportionate symbols

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A map is a representation of the earth’s surface or a part of the earth’s surface. Different maps serve different purposes.

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Maps and symbols

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No. Types of Map Uses

1 Base maps Focus on basic information or highlight important information by providing an outline of the area.

2 Atlas Provide details of natural and human features/occurrences of places.

3 Topographical maps

Show physical and human features through the use of lines, symbols, colours and abbreviations.

4 Road maps Road maps show the location of roads, buildings, railway tracks and airports, and used as navigation tool.

5 Sketch maps Sketch maps are simplified illustrations of an area, drawn to show the basic positions of an area’s main features.

6 Choropleth maps

Show the geographical distribution and trends using colours or shadings to group different data values

7 Isoline maps Isoline maps are maps with isolines, or continuous lines joining points of equal value

8 Dot maps Dot maps show the distribution of data using dots. The dots have a fixed size or value and are drawn on a base map.

9 Maps with proportionate symbols

Symbols drawn are proportional to the values of the data being mapped. For example, bigger symbols are accorded to larger values.

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No. Scenario

• Kim and family needs directions to drive from Singapore to Melaka, Malaysia over the weekend.

• A soldier is lost in the jungle, and he needs to find the nearest water source as soon as possible.

• A tourist who wants an overview of the key geographical features in Spain.

• A geographer wants to know where all the less developed countries and developed countries are located in the world.

• A researcher needs a basic map showing just the continents in the world so that he can plot important information onto the map.

• A doctor needs to know which countries in the world have high infant death rate.

• A pilot is flying across the Atlantic ocean, and needs to know the areas with the same level of pressure so that he can navigate around safely.

• A student is conducting a field study trip, he needs to make observations and record down the coastal environment he is studying.

• A geologist who wants to show the distribution of volcanoes in the world.

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No. Scenario

4 • Kim and family needs directions to drive from Singapore to Melaka, Malaysia over the weekend.

3 • A soldier is lost in the jungle, and he needs to find the nearest water source as soon as possible.

2 • A tourist who wants an overview of the key geographical features in Spain.

6 • A geographer wants to know where all the less developed countries and developed countries are located in the world.

1 • A researcher needs a basic map showing just the continents in the world so that he can plot important information onto the map.

9 • A doctor needs to know which countries in the world have high infant death rate.

7 • A pilot is flying across the Atlantic ocean, and needs to know the areas with the same level of pressure so that he can navigate around safely.

5 • A student is conducting a field study trip, he needs to make observations and record down the coastal environment he is studying.

8 • A geologist who wants to show the distribution of volcanoes in the world.

Photographs and satellite images are primary data which provide vital information about the physical features and human activities at a particular place and time.

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Photographs and satellite images

Different types of photographs and satellite images

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Landscape photographs

Aerial photographs

• Taken from a ground level perspective and give a horizontal view of an area

• Show the landscape in great detail, allowing features and patterns to be observed

• More details in the background can be seen due to the height in which photograph is taken.

• Size will not be distorted, and useful for map making.

• Taken from space, allows large area to be captured.

• Can show the development of place over time.

Satellite images

Interpreting photographs

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1. What HUMAN features (Transport and communication networks, e.g. roads, railways, satellite stations) are shown in the photograph?

2. What PHYSICAL features (relief, coast, vegetation) are shown in the photograph?

3. Why are these features present?4. What effects do these features

have on the physical and human environments?

A graph is a diagram used to represent data which shows the relationship between two or more variables. A variable is something that is measured and which helps us understand data more easily.

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Graphs

• Line graphs• Bar graphs• Histograms• Pie charts• Scattergraphs• Climographs• Triangular graphs (For GCE O-Level only)

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Graphs

Simple line graphs

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1. Decide on your independent (x-axis) and dependant variable (y- axis)

2. Plot the value of both variables on the graph paper.

3. Deduce the relationship between the two variables i.e as air temperature increases, the air can hold higher amounts of water vapour.

Air temperature: independent variable

Water vapour: dependent variable

Comparative line graphs

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Allows comparison of two or more sets of data

Compound line graphs

Allows one set of data to be sub-divided into two or more sets of data

Bar graphs

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1. Decide on your independent (x-axis) and dependant variable (y- axis).

2. Plot the value of both variables on the graph paper.

3. Compare the values among the different independent variables. i.e Indonesia has highest fatalities related to tectonic activities among the other 3 countries.

Comparative bar graphs

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Allows comparison of two or more sets of data

Compound bar graphs

Allows one set of data to be sub-divided into two or more sets of data

Histogram

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1. Histograms show distribution or frequency of data. The x-axis shows the range of values.

2. The values do not overlap. The y-axis shows the frequency.

3. Different from bar graphs because x-axis states size/classes and not categories.

Pie charts

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1. Pie charts are circular graphs divided into segments.

2. Each segment of a pie chart represents the portion a variable takes up.

3. Each data set has to be converted into a percentage of the data set.

Scattergraphs

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1. Plot data using ‘X’s.2. Draw a straight line of best fit. This will broadly represent

the general pattern formed by the two points.3. Take note of any anomalies.

Climographs

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1. A climograph shows how mean monthly temperature and total monthly precipitation vary throughout the year for a particular place.

2. The temperature is shown using a line graph while the precipitation is shown using a bar graph.

Describing climographs

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When describing climograph, always state the:1.The months where the minimum and maximum temperatures are experienced.2.The average temperature range (using key terms in (a) and (b))3.The months where it minimum and maximum rainfall are experienced.4.The total amount of rainfall experienced in the place (using key terms found in (c))

Triangular graphs

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Triangular graphs are equilateral triangles showing the relationship between three data sets where the variables add up to 100.

When reading triangular graphs:1.Determine the point you are reading the value of.2.Look at the base of the triangle and determine the direction of 0 to 100. (is it left to right? or right to left? In this case, it is left to right)3.Draw a line from the designated point in the direction determined in 2. (in this case, towards the left) and take the first reading.4.Insert the two other lines as shown in the figure.5.Check and ensure all three readings add up to 100.

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Triangular graphs Cont.

0 100

0

100

100

0 0

100

100

0

100 0

A A

B

C

BC

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Other ways of presenting data

Statistical calculation

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Statistical calculations aid analysis by providing more precise calculations. Common statistical calculations are percentages,

ratios, mean, median and mode.

The phases in fieldwork

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• Gateway 3: Geographical investigations

a. Pre-fieldwork

b. During fieldwork

c. Post-fieldwork

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CHAPTER 3 GEOGRAPHICAL SKILLS AND INVESTIGATION

Suggesting a hypothesis or guiding question

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Hypothesis Guiding QuestionExpressed as a statement Expressed as a question

Consist of a prediction May consist of a problem

Explanation for something that needs to be tested or proven

Highlights what needs to be known about a topic

Can have more than two variables

“How long does a Secondary 4 student spend in the washroom?”

Does not need to have an independent or dependent variable

“The older the student, the longer the time they spend in the washroom.”

Collecting data

• Recording observations• Taking measurements

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Recording observations

1. Annotated photographs2. Recording sheets3. Maps4. Cloud cover

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Annotated photographs and recording sheets

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• Photographs can be used to record the features on the fieldwork site for future reference.

• Annotations can be added to photographs to help highlight essential information.

• Data collection is more organised when tables are included in recording sheets

Maps and cloud cover

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• Maps show the location of physical features and human activities.

• Maps can also be annotated with the locations of recorded data. Further data analysis and presentation can then be carried out after fieldwork has been done.

• Cloud cover symbols indicate the amount of solar radiation that reaches the earth’s surface.

Taking measurements

• Wind speed and direction• Air pressure• Temperature• Relative humidity• Precipitation

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Wind speed and direction

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Anemometer•Hold up the anemometer in an open area where wind flows freely. •Read the wind speed indicated.

Anemometer Wind vane

Wind rose

Wind vane•Place the wind vane at where the wind is blowing. •The direction the wind vane points to is the direction where the wind is blowing from.

Wind rose•The rectangles point in the direction where wind is blowing from.•The numbers indicate the days of the month where the wind is blowing.

Air pressure

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• Air pressure is measured in millibars (mb) using a barometer.

• A barometer has two needles. Check that the moveable pointer is arranged over the measuring hand to mark the current pressure.

• The pressure is falling if the measuring hand moves to the left, and rising if the measuring hand moves to the right.

Temperature

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• Temperature is measured using an analogue or digital thermometer.

• Temperature is read on a maximum and minimum thermometer by observing the lowest point of each metal index (blue line). For example, in the figure, the minimum temperature is 20°C and the maximum temperature is 25°C.

• The diurnal temperature range is therefore 5°C.

A digital thermometer

A maximum and minimum thermometer

Relative humidity

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Relative humidity is measured using a sling psychrometer, which consists of a wet bulb thermometer and a dry bulb thermometer. To calculate:1.Dip the wick of the wet bulb in water and swing the psychrometer for 1 min.2.Record the reading. Repeat step 1 until both readings are consistent.3.Read the temperature off the dry bulb.4.To obtain the depression of the wet bulb, calculate the difference between the wet bulb temperature and the dry bulb temperatures.5.Using the conversion table, obtain the relative humidity by finding the value where the wet bulb depression intersects with the dry bulb temperature.

Precipitation

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The amount of precipitation is measured in millimetres using a rain gauge. A simple rain gauge can be made using a funnel and a jar or tin. To determine the amount of precipitation:1.Find an appropriate spot to place your rain gauge and position the rain gauge in an open area.2.Place the rain gauge into the ground with about 30 cm protruding above ground. 3.Record the time at which the rainfall events start and end.4.Pour the collected water in the rain gauge into a measuring cylinder. Read and record the water level.

Post-fieldwork

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