GIS, Contours & Fieldwork (Years 10–11) — Geography

Contour lines and spot heights show a landscape's shape, GIS layers geographical data, and fieldwork answers real questions by collecting and presenting primary data.

Look at a map of brown wavy lines and, once you can read them, a whole hill rises off the page: gentle where the lines are far apart, steep where they crowd together. Contours turn a flat sheet into a three-dimensional landscape.

Why this matters — Height decides where rivers flow, where floods gather and where roads can climb. Reading relief, using GIS and doing fieldwork are the practical skills geographers use every day.

Showing height: contours and spot heights

A contour line joins all points at the same height above sea level.
Lines close together mean a steep slope; lines far apart mean a gentle slope.
Concentric (ring-inside-ring) contours show a hill, with the highest ring in the middle.
A spot height is a dot with an exact height number; a triangulation point marks a surveyed summit.

Rings inside rings = a hill; here it peaks just above 40 m.

Reading a cross-section

A cross-section is a side view along a line. Where you cross the 10, 20, 30 and 40 m contours, mark that height, then join the marks to draw the hill's profile. Closely spaced contours become a steep part of the line; widely spaced ones become gentle.

Each contour crossing becomes a point on the profile.

GIS and fieldwork

GIS (Geographic Information System) stores geographical data in layers you can switch on and off over the same map — roads, rivers, population, flood zones. Because every layer is tied to a real location, stacking them lets you ask powerful questions: which homes sit in a flood zone and more than a mile from a road?

GIS stacks layers on one location so you can query them together.

Layering data reveals patterns invisible on a single map, so planners, aid workers and scientists use it to decide where to build, where to send help and what to protect. The maps on your phone are GIS in action.

Fieldwork is how geographers gather their own evidence rather than relying on others. A good enquiry is a small piece of real science: you pose a clear question, collect primary data (measurements you take yourself, like river width or traffic counts), present it in graphs and maps, then draw a reasoned conclusion and judge how trustworthy it is.

Primary data plotted: velocity rises downstream, answering the enquiry.

Fieldwork step	What you do
1 Question	Ask an enquiry, e.g. 'Is the river faster downstream?'
2 Collect	Gather primary data by measuring yourself
3 Present	Show it in graphs, maps or tables
4 Conclude	Answer the question and evaluate

Worked example: On a hill map the 10, 20, 30 and 40 m rings are evenly spaced on the south side but bunched on the north. The south slope is therefore gentle and the north slope steep — a walker would climb up the north face but stroll down the south.

Common mistake: Thinking wide contours mean high ground. Spacing shows steepness, not height; the number on the line shows height. Rings inside rings mean a hill, not a hollow.

Memory hook: "Close contours, calf-burning climb." Crowded lines = steep; spread-out lines = gentle. And GIS is just a map made of stackable layers.