World population distribution and density

Understanding why people live where they do is fundamental to Human Geography. CCEA examiners expect you to describe global population distribution using the correct terminology, and to explain the physical and human factors that make some areas densely or sparsely populated.

Global distribution patterns

Most densely populated regions:

• South and South-East Asia (India, Bangladesh, Indonesia, China's eastern coastal cities).
• Western Europe (Netherlands, Belgium, UK).
• North-eastern USA (the "megalopolis" from Boston to Washington DC).

Most sparsely populated regions:

• Hot deserts (Sahara, Arabian Desert, Australian Outback).
• Cold environments (Arctic, Antarctic, Siberia, Canadian Shield).
• High mountains (Himalayas, Andes above 4,000 m, Tibetan Plateau).
• Dense tropical rainforest (Amazon, Congo Basin).

NI context: NI has a population of approximately 1.9 million (2021 Census). Population density is ~139/km². The east (Greater Belfast, Ards Peninsula) is far more densely populated than the rural west (Fermanagh, west Tyrone).

Physical factors affecting population density

Favourable (attracting people):

• Climate: moderate temperatures, reliable rainfall (not too hot/cold/dry). Western Europe's temperate maritime climate is ideal for farming and comfortable living.
• Relief and terrain: flat or gently rolling land is easier to farm, build on, and travel across. River valleys and coastal plains are magnets for settlement.
• Soil quality: fertile soils (alluvial river plains, volcanic soils) support high agricultural productivity → support larger populations.
• Water supply: access to rivers, lakes, or reliable rainfall. Almost all major ancient civilisations developed beside rivers (Nile, Tigris-Euphrates, Indus).
• Natural resources: coalfields (South Wales, Ruhr Valley) attracted dense industrial populations in the 18th–20th centuries; oil fields (Gulf states) attract workers today.

Unfavourable (limiting population):

• Extreme climate: hot deserts (unreliable water, extreme heat), polar regions (extreme cold), monsoon flood zones.
• High relief: above 4,000 m (thin air, extreme cold, poor soils, difficult access).
• Poor soils: tropical rainforest soils (latosols) are nutrient-poor once vegetation is removed.
• Lack of water: deserts have very limited agricultural potential.

Human factors

• Economic opportunity: cities attract people because they offer more jobs, higher wages, and better services. This explains why coastal cities and capital cities are so densely populated.
• Historical factors: once a settlement is established, it tends to grow further (infrastructure investment, social networks). Belfast grew around its port and linen industry.
• Political factors: borders, refugees, and government policies can dramatically affect where people live.