Maps — Choropleth, Flow Maps, and Annotated Sketches
Part of Fieldwork Presentation and Evaluation Skills — GCSE Geography
This deep dive covers Maps — Choropleth, Flow Maps, and Annotated Sketches within Fieldwork Presentation and Evaluation Skills for GCSE Geography. Revise Fieldwork Presentation and Evaluation Skills in Geographical Skills for GCSE Geography with 0 exam-style questions and 20 flashcards. This topic shows up very often in GCSE exams, so students should be able to explain it clearly, not just recognise the term. It is section 6 of 16 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 6 of 16
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0 questions
Recall
20 flashcards
🗺️ Maps — Choropleth, Flow Maps, and Annotated Sketches
Map-based presentations are used when location matters — when the spatial pattern of the data is what you are trying to communicate. If you can answer your research question without knowing where things happened, you probably do not need a map. But if the spatial distribution, direction of movement, or relative values across areas are central to the enquiry, a map is essential.
Choropleth Maps
A choropleth map uses different shading intensities or colours to show how a variable varies across different areas. Darker shading conventionally means higher values. They are most commonly used for showing deprivation, population density, crime rates, or land use proportions across named zones or administrative areas.
Drawing a choropleth correctly:
Key limitation: a choropleth assumes values are uniform across each zone. In reality, a deprived ward might have very wealthy streets in one corner. The map hides this within-zone variation — a significant weakness when analysing at a fine-grained level.
Flow Maps and Desire Lines
A flow map (or desire line map) shows the movement of people, goods, or traffic between places. The width of each line is proportional to the quantity of flow; the direction shows where the flow goes. They are used in pedestrian survey data (where are people coming from?), migration studies, and trade flow analysis.
The term desire line specifically means a straight line drawn between an origin and destination, regardless of the actual route taken. It shows the direction and relative volume of movement without implying that this is the route followed.
Annotated Field Sketches and Photographs
A field sketch or annotated photograph is a form of primary evidence — it records what the site actually looked like. But its value for marks depends entirely on the quality of the annotations.
The difference between a description and an annotation:
| Label (Description Only) | Annotation (Geographical Explanation) |
|---|---|
| "Narrow channel here" | "Narrow channel concentrates flow, increasing velocity — consistent with upper-course characteristics in the Bradshaw Model" |
| "Pebbles on beach" | "Angular pebbles indicate short transport distance from cliff — attrition has not yet rounded the sediment" |
| "Buildings are close together" | "High building density suggests this is the CBD — high land values force maximum use of available floor space" |
Minimum requirements for a GCSE annotated photograph: at least 3 annotations, each making a geographical point (linking a visible feature to a geographical process, theory, or pattern). Simply labelling features with their names earns description marks only.
Isoline Maps
An isoline connects points of equal value on a map — the same principle as contour lines on an OS map, but applied to any measured variable (noise levels, temperature, pollution concentrations). Lines are drawn by interpolating between known data points. Isolines never cross; they are labelled with their value; they close or run to the edge of the map.