0.0° 0.0°Where the equator meets the prime meridian
Five ideas to learn first
- Location. Every place has an address on a global grid of latitude and longitude. Once you can read it, you can find anywhere on any map or app.
- Maps flatten a sphere. A globe is the only map without distortion. Every flat map stretches something, and knowing what it stretches stops you misjudging sizes and distances.
- Elevation. Contour lines turn a flat sheet into a 3D landscape. Reading them lets you see hills, valleys and steep ground before you get there.
- Time follows the sun. Earth turns about 15 degrees an hour, so clocks are set by zones. Politics then bends those zones into odd shapes.
- Land and climate are built by forces. Plate movement raises mountains, water and ice carve them down, and latitude, oceans and altitude set the climate.
Suggested reading order
The posts build on each other in this order. Each takes 5 to 10 minutes.
51.5°N 0.0°
Greenwich, London
Latitude and longitude, explained
How the grid of parallels and meridians pins down any spot on Earth, and how to read and convert coordinates.
64.2°N 51.7°W
Nuuk, Greenland
Map projections: why every flat map distorts
Mercator, equal-area and compromise maps, what each one stretches, and how to pick the right one.
54.5°N 3.2°W
Scafell Pike, England
Map reading basics: scale, legend and compass
Scale, grid references, the three norths and orienting a paper map with a compass.
46.9°N 121.8°W
Mount Rainier, Washington
How to read contour lines on a topographic map
Contour intervals, index contours and the shapes that mark ridges, valleys, saddles and cliffs.
27.7°N 85.3°E
Kathmandu, Nepal
How time zones work, from UTC to the date line
Why the world uses about 15 degrees per hour, where the odd half-hour offsets are, and how to convert times.
3.1°S 60.0°W
Manaus, Brazil
Climate zones and the Köppen system
The five main Köppen groups, what the letter codes mean, and the forces that set a place's climate.
36.1°N 112.1°W
Grand Canyon, Arizona
Landforms explained: how Earth's surface takes shape
Mountains, plateaus, plains, canyons, dunes and coasts, and the forces that build and wear them down.
30.0°N 31.2°E
Cairo, on the Nile
How rivers work: from source to delta
Drainage basins, meanders, floodplains and deltas, plus why river lengths are so hard to pin down.
28.0°N 86.9°E
Mount Everest
How mountain ranges form
Fold, fault-block and volcanic mountains, what tectonic plates have to do with them, and how mountains shape weather.
Tips for students
- Keep a globe or an atlas nearby. Look up every place a post mentions; the coordinates on each card make that quick.
- Compare the same region on two different world maps. Seeing Greenland shrink between projections teaches more than any definition.
- Sketch. A rough map from memory, with the equator, tropics and a few rivers, shows you what you know and what you don't.
- Learn the vocabulary in pairs: weather and climate, latitude and longitude, source and mouth, true north and magnetic north.
- Use a terrain view in a free online map to check what contour lines on a paper map are telling you.
Tips for travelers
- Check the time difference in UTC terms, and check whether either place is on daylight saving time on your dates. See time zones.
- Check the climate type and the season. South of the equator, seasons are reversed, and in the tropics the wet and dry seasons matter more than temperature. See climate zones.
- Check the elevation. Air cools with height, and many people feel altitude effects above about 2,500 m (8,000 ft). Mountain towns can be far colder than the lowlands nearby.
- Carry a paper map for hiking, and learn the map reading basics before you need them. Phones run out of battery and signal.
A short glossary
- Equator
- The line of 0° latitude, halfway between the poles.
- Prime meridian
- The line of 0° longitude, through Greenwich in London.
- Projection
- A method of drawing the curved Earth on a flat surface.
- Contour line
- A line on a map joining points of equal elevation.
- Scale
- The ratio between a distance on the map and the same distance on the ground.
- UTC
- Coordinated Universal Time, the reference that time zones are measured from.
- Drainage basin
- All the land that drains into one river and its tributaries.
- Plate tectonics
- The theory that Earth's outer shell is split into moving plates.
Start-here questions
What should I read first?
Start with latitude and longitude. Coordinates come up in almost every other post, and they take only a few minutes to learn.
Is physical geography the same as earth science?
They overlap a lot. Earth science leans toward geology, oceans and the atmosphere as systems, while physical geography is more interested in where features are, how they are distributed and how they appear on maps.
How do I remember which way latitude runs?
Lines of latitude run east to west like the rungs of a ladder, and the numbers tell you how far up or down the ladder (north or south) you are. Longitude lines run from pole to pole.