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Explore the evolution of global population trends from 1950 to the predictions for 2015, including challenges, growth rates, distribution, and movement. Learn about factors influencing human migration and settlement patterns.
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Chapter 4 Section 1 In 1950 New York was the only metropolitan area in the world with a population over 10 million. By 1994, 14 world cities had populations greater than 10 million. Four of these cities were in economically developed countries; the rest were in countries still developing modern economies. By 2015 experts predict that the population of the following cities will exceed 20 million: Tokyo, Mumbai, Lagos, Shanghai, Jakarta, São Paulo, and Karachi. Of these cities only Tokyo is in an economically developed country.
Population Growth • The population of Earth is now about 6 billion and is expected to reach 7 billion by 2010. People inhabit about 30 percent of the planet’s land.
Growth RatesWorld population is growing rapidly because birthrates have not declined as fast as death rates. • Improved diet and health care have lowered the death rate in many places. • In economically developing countries, the birthrate is often very high. • Wealthy industrialized countries, however, tend to have a low birthrate
Challenges of Population GrowthWorld food production has risen to meet demands on every continent except Africa. • However, rapidly growing populations still face shortages of freshwater, housing, and clothing.
Negative Population GrowthIn some countries the death rate is higher than the birthrate. • Countries with negative growth rates often recruit workers from other countries to supplement their workforce.
Population Distribution • Population DensityThe earth’s people are not evenly distributed over the available land. • Most people live near sources of freshwater and in areas where the climate is temperate. • Population densitymeasures the average number of people living on a square mile or square kilometer of land.
Population MovementMore and more people throughout the world are moving to urban areas in search of better jobs, education, and health care. • About half the world’s people now live in urban areas. • People also migrate from one country to another, seeking greater economic opportunities and political freedom. 3.3 analyze factors that influence human movement and settlement patterns