World population 4.1

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Transcript of World population 4.1

Chapter 4 Section 1

World Population

Current World Population: 7 billion

Growth RatesWorld pop is growing

rapidly b/c birthrateshave not declined as fast as death rates.

Death RatesAre the number of

deaths per year in 1,000 people.

Improved diet and health care have lowered the death rate in many industrialized nations.

Death Rate

BirthrateIs the number of

births for every 1,000 people.

In economically developing countries, the birthrate is high.

In wealthy industrialized countries, the birthrate is low.

Birthrates

Challenges to Population Growth

World food production has risen to meet the demands on every continent except Africa.

However, rapidly growing populations are facing shortages of freshwater, housing, and clothing.

Negative population growth

In some countries, the death rate is higher than the birthrate.

Countries like this often recruit workers from other countries to supplement their workforce.

Population DensityThe Earth’s people are

not evenly distributed over available land.

Most live by freshwater sources and in temperate climates.

Population density measures the average number of people living on a square mile of land.

Population Density Continued

Population density formula:

Population of a country

Total land area of a

country

Canada: 8 ppl per sq. mi. Bangladesh: 2,401 ppl per sq. mi.

Belgium and Niger both have a population of 10.3 mil. But, Belgium is smaller (872 ppl per sq. mi.) and Niger is larger (21 ppl per sq. mi.)

Population Density

Population Movement (migration)

More people are moving to urban areas looking for better jobs, education, and healthcare.

½ the world’s ppl live in urban areas.

Ppl also migrate from other countries for greater economic opportunities and political freedom.