Physical Geography

The smallest continent — dry, flat 'island continent' Australia — and the frozen, uninhabited White Continent of Antarctica.

The atmosphere is a thin envelope of gases held by gravity, made mostly of nitrogen and oxygen and arranged in five layers, each with its own character.

How the continents move — from Wegener's drifting Pangaea to sea-floor spreading and the modern theory of plate tectonics.

The Earth is one of eight planets orbiting the Sun, the only one known to support life because of its distance from the Sun, its atmosphere and its water.

A peninsula of Eurasia — small but densely populated, with a mild climate, busy rivers and a long industrial history.

The internal and external forces that shape the Earth's surface — and how compression and tension fold and fault the rocks.

The places where people live — from tiny hamlets to giant cities — classified as rural or urban, and the problems of rapid urban growth.

The Earth is built of three concentric layers — crust, mantle and core — known mainly from the way earthquake waves travel through the planet.

The high-altitude rivers of air that steer the weather, and the great low-pressure storms — temperate and tropical cyclones.

Three of our most precious natural resources — the land we live on, the soil that feeds us, and the water we depend on — and how to protect them.

A grid of latitudes and longitudes drawn on the globe lets us fix the exact location of any place on the Earth and work out its local time.

How the round Earth is shown on flat paper — what a map is, its types, its components and the essentials of making one.

The Earth has two motions, rotation on its axis and revolution around the Sun, which together cause day and night and the cycle of seasons.

The third-largest continent — the 'New World' of the Canadian Shield, Western Cordilleras, Great Lakes and rich farmlands.

The sediments that settle on the sea floor, and the great living structures built by coral — their conditions and types.

Why the sea is salty — what salinity is, how it is measured, what controls it, and how it drives ocean density.

How the sea is heated and how its temperature changes with depth and latitude — including the all-important thermocline.

The restless motion of the seas — waves, tides and currents — and how these movements shape coasts and climate.

The make-up of a population by sex, age, residence and occupation, shown through measures like the sex ratio and the age-sex pyramid.

The three great families of rocks that build the Earth's crust — igneous, sedimentary and metamorphic — and how they change into one another.

The fourth-largest continent — the high Andes, the mighty Amazon, the Atacama desert and the world's largest rainforest.

The Earth is warmed by incoming solar radiation called insolation, and it stays in balance by sending an equal amount of heat back to space.

The hidden relief beneath the seas — from the gently sloping continental shelf to the deepest ocean trenches.

Climates can be grouped into a few great types using Koeppen's scheme, while the climate of the whole planet is now shifting because of human-driven global warming.

Where the world's people live, why they cluster in some places, and how population grows through births, deaths and migration.