GIS and Image Skills » Source Improvement Suggestions

What you'll learn this session

Study time: 30 minutes

How to identify limitations in geographical sources
Techniques to improve maps, graphs and diagrams
Methods to enhance satellite images and photographs
How to suggest practical improvements to data collection methods
Skills to critically evaluate geographical information

Introduction to Source Improvement in GIS

When working with geographical data and images, it's essential to understand their limitations and how they could be improved. In your iGCSE Geography exam, you might be asked to suggest improvements to maps, graphs, photos, or other geographical sources. This skill shows your ability to think critically about the information presented to you.

Key Definitions:

Source improvement: Suggesting ways to enhance the quality, accuracy, or usefulness of geographical information.
Data reliability: How trustworthy and consistent the information is.
Data validity: Whether the data measures what it claims to measure.
Spatial resolution: The level of detail visible in an image or map.

🔍 Why Improve Sources?

All geographical sources have limitations. Improving them helps us:

Get more accurate information
Make better decisions
Reduce misinterpretation
Present data more clearly
Compare data more effectively

📝 Exam Technique

When suggesting improvements:

First identify the specific problem
Suggest a practical solution
Explain how it would help
Consider cost and feasibility
Link to geographical purpose

Improving Maps and Diagrams

Maps and diagrams are essential tools in geography, but they often have limitations that can be improved upon.

Common Map Issues and Solutions

🗺 Scale Problems

Issue: Scale too small or missing

Improvement: Add a clear scale bar or ratio (e.g., 1:25,000). Use an appropriate scale for the purpose - larger scale for local studies, smaller for regional.

📍 Missing Features

Issue: Key geographical features omitted

Improvement: Add relevant features like rivers, settlements, or contour lines. Include a comprehensive key explaining all symbols used.

🛡 Orientation Issues

Issue: No north arrow or grid references

Improvement: Add a north arrow and grid references to help with navigation and location descriptions. Ensure consistent orientation.

When suggesting improvements to maps, always consider the purpose of the map. A tourist map needs different features compared to a flood risk map or a population density map.

Enhancing Graphs and Charts

Graphs and charts help us visualise data, but poor design can lead to misinterpretation or confusion.

📈 Line and Bar Graphs

Common issues:

Missing axis labels or units
Inappropriate scale (too compressed or stretched)
No title or data source
Too many variables making it cluttered

Improvements:

Add clear labels and units to both axes
Use appropriate scales that don't distort trends
Include a descriptive title and data source
Limit variables or use multiple graphs
Add a key if multiple data sets are shown

📊 Choropleth Maps

Common issues:

Poor colour choices (hard to distinguish)
Inappropriate data categories
Missing or confusing key
No indication of data source or date

Improvements:

Use a logical colour progression (e.g., light to dark)
Create appropriate data categories (equal intervals or quartiles)
Include a clear key with all categories
Add data source, date and title
Consider using patterns for colour-blind accessibility

Case Study Focus: Improving River Flood Data Presentation

A student was given a simple line graph showing river discharge over time but found it difficult to interpret flood risk. Suggested improvements included:

Adding a horizontal line showing the flood threshold level
Including rainfall data on a secondary axis to show the relationship
Marking historical flood events for context
Using different colours to highlight dangerous discharge levels
Adding annotations explaining key rises and falls

These changes transformed a basic graph into a useful tool for flood risk assessment.

Improving Satellite Images and Photographs

Satellite images and photographs provide valuable visual data but often need enhancement to be most useful.

Satellite Image Improvements

Satellite images can be powerful tools but often have limitations that need addressing:

🌎 Resolution Issues

Problem: Low resolution making details unclear

Solution: Use higher resolution imagery if available, or focus on a smaller area. Suggest using more advanced satellites or drones for better detail.

🌈 Cloud Cover

Problem: Clouds obscuring ground features

Solution: Use radar imagery (which penetrates clouds), composite images from multiple dates, or specify imagery from dry seasons.

📑 Context Issues

Problem: Difficult to interpret without context

Solution: Add labels, boundaries, scale and orientation. Include a small inset map showing location in wider context.

Field Photographs

Field photographs are common in geographical studies but often need improvements to maximise their usefulness:

📷 Common Photo Issues

No scale reference (hard to judge size)
Poor lighting or weather conditions
Limited perspective (only one angle shown)
No location information or coordinates
Seasonal limitations (e.g., vegetation hiding features)
No date (making temporal comparisons difficult)

🛠 Photo Improvement Techniques

Include a scale object (person, ruler, coin)
Take photos in different lighting conditions
Capture multiple angles and perspectives
Record precise location (GPS coordinates)
Take repeat photos across seasons/years
Add annotations highlighting key features
Include compass direction of the view

Improving Data Collection Methods

Sometimes the issue isn't with how data is presented but with how it was collected in the first place.

📏 Sample Size

Issue: Too few samples leading to unreliable results

Improvement: Increase sample size, use stratified sampling techniques, or conduct repeated sampling over time.

📆 Timing

Issue: Data collected at inappropriate times

Improvement: Collect data at different times of day/week/year to account for variations. Use continuous monitoring where appropriate.

🔬 Equipment

Issue: Inaccurate or unsuitable equipment

Improvement: Use more precise instruments, digital rather than manual methods, or calibrate equipment regularly.

Exam Tip: The SPACC Method

When suggesting improvements to any geographical source, remember the SPACC method:

Scale - Is the scale appropriate? How could it be improved?
Presentation - How is the data presented? Could it be clearer?
Accuracy - How accurate is the data? How could accuracy be improved?
Completeness - What information is missing? What should be added?
Context - Is there enough background information? What context is needed?

Using this method will help you provide comprehensive improvement suggestions in your exam.

Practical Application

Being able to suggest improvements to geographical sources isn't just an exam skill - it's a valuable real-world ability that geographers use daily. When you look at any map, graph, or image, get into the habit of asking:

What is this source trying to show?
Does it do that effectively?
What's missing or could be clearer?
How would I improve it if I were creating it?

Remember that the best improvements are specific, practical and directly address the limitations of the original source. Generic suggestions like "make it clearer" won't earn you many marks in an exam - you need to explain exactly how you would make it clearer and why that would help.

🧠 Test Your Knowledge!