IB Geography: Extreme Environments Revision

Quick check · one tap

What is the difference between erosion and deposition?

Extreme Environments is a core part of IB Geography. Revise the key concepts and common mistakes below, then lock them in with the free games.

Key concepts

Hot desertRegion receiving less than 250 mm precipitation per year, with high diurnal temperature range.

SaharaWorld's largest hot desert at approximately 9.2 million km², stretching across North Africa.

WadiDry channel that experiences flash floods during rare rainfall events.

XerophytePlant adapted to arid conditions through deep roots, small leaves or water storage.

SahelSemi-arid transition zone south of the Sahara, particularly vulnerable to desertification.

Great Green WallAfrican initiative since 2007 to plant trees across the Sahel to combat desertification.

Antarctic Treaty (1959)Agreement designating Antarctica for peaceful, scientific use; in force from 1961.

PermafrostPermanently frozen ground, ranging from continuous to sporadic, that thaws in surface 'active layer'.

Katabatic windCold dense air flowing downhill from ice plateaux, often reaching destructive speeds.

Ice shelfFloating extension of glacier ice over the ocean.

KrillSmall crustacean that anchors the Antarctic food web supporting whales, seals and penguins.

Madrid Protocol (1991)Environmental protocol to the Antarctic Treaty designating the continent a 'natural reserve devoted to peace and science'.

OrogenyProcess of mountain building through tectonic collision, e.g. Himalayan orogeny from ~50 Ma.

Altitude sicknessAcute mountain sickness from low oxygen, beginning above ~2,500 m.

Learn Extreme Environments step by step

Free interactive mini-lessons: short screens, worked examples and quick checks. Pick your exam board to open its course map, then tap L on this topic:

HL SL

Common mistakes to avoid

Questions where students often pick the tempting wrong answer — make sure you know the right one:

What is the difference between erosion and deposition?✗ They mean the same thing. ✓ Erosion wears away and moves material; deposition drops it.

Practise Extreme Environments — free games

Test yourself with these quick revision games for this topic:

▶ Two Truths, One Lie ▶ Reveal Race ▶ Connections Grid ▶ Falling Words ▶ Word Web

See all 22 games in the Revision Arcade →

Extreme Environments

Key concepts

Common mistakes to avoid

Practise Extreme Environments — free games

More IB Geography topics