Year 8 and Year 9 Geography: Population, Glaciers, and African Deserts

Vocabulary practice cards focusing on glacial landforms, global population patterns, demographic models, and desertification in Africa.

Population distribution

The pattern of where people live and how they are spread out across an area.

Sparsely populated

An area characterized by having few people per square mile.

Densely populated

An area characterized by having many people per square mile.

Coast

The zone where land meets the sea, which attracts large populations by providing trade links and expanding job opportunities.

Corrie

An armchair-shaped hollow found on the side of a mountain, largely formed by glacial erosion during ice ages.

Zone of accumulation

The hollow area where snowflakes collect, compress under accumulating weight, and squeeze out air to turn into dense glacial ice.

Freeze-thaw weathering

A mechanical weathering process above a glacier where water repeatedly freezes and expands in rock cracks, shattering rock that falls into the ice.

Plucking

A glacial erosion process where meltwater freezes onto rock beneath the glacier and tears blocks away as the ice moves, steepening the back wall of a corrie.

Abrasion

A glacial erosion process in which rocks embedded in the base of moving glacier ice scour and scrape the underlying bedrock, deepening the corrie hollow.

Rock lip

A raised ridge of deposited rock at the outer edge or threshold of a corrie formed when the glacier melts.

Arête

A sharp, narrow knife-edge ridge of rock formed between two neighboring corries eroding back-to-back or side by side.

U-shaped valley

A wide, steep-sided, flat-bottomed valley carved out when a glacier widens and deepens an existing V-shaped valley, cutting off interlocking spurs and leaving hanging valleys with waterfalls.

Demographic Transition Model (DTM)

A model illustrating how birth rates, death rates, and total population size change over time across five distinct stages as a country develops.

Underpopulation

A state where an area contains too few people to fully exploit or utilize the available natural resources and technology, as observed in Russia.

Order of Paternal Glory

A Russian honorary medal awarded to parents who have $7$ children to encourage higher birth rates and counter demographic decline.

Overpopulation

A condition where an area's population exceeds available resources, lowering the standard of living and slowing down development.

One Child Policy

A population control policy introduced in China in $1979$ that mandated family planning through incentives like free child care and pensions, alongside severe legal and financial penalties.

Sahel

A fragile semi-arid geographic belt in northern Africa bordering the southern Sahara Desert, receiving only up to $100\,\text{mm}$ of rainfall annually.

Desertification

The progressive degradation and drying out of fertile, productive land into unusable desert terrain, accelerated by climate stress, overcultivation, and overgrazing.

Zaï Pits

A traditional soil-water conservation method where crops are planted in small, bowl-shaped hollows that collect runoff and hold composted animal dung to attract burrowing termites.

Great Green Wall of Africa Project

An ecological land restoration initiative centered on planting trees across the Sahel to halt desertification, which alongside stone bunds has recovered $40\%$ of degraded land.

Desert biome

An arid biome characterized by thin, infertile soils, low and intermittent precipitation, and extreme temperatures that fluctuate between $30^\circ\text{C}$ and $50^\circ\text{C}$.

Desert primrose

An adapted desert plant whose hardy seeds remain dormant in sand for months or years, germinating and growing rapidly within $2\,\text{weeks}$ following rare rain events.