GEOGRAPHY
A GROWING POPULATION
BEFORE YOU READ
Reach into your background
If you called a hospital in your community, you could find out how many babies were born last week. Multiply that number by all the hospitals. Subtract from this figure the number of people who died both in and out of hospitals. That’s one way to find out how much the world’s population increased in seven days.
Question to explore
1 .How fast is the world’s population growing?
2. What challenges are created by the worlds growing population?
Key terms
Birth care
Death rate
Life expectancy
Green Revolution
Imagine that all the years from A.D. 1 to A.D. 2000 took place in just 24 hours. Now you have an imaginary clock to measure how fast the world’s population is growing .The list below shows that the Earth population doubled several times in those 24 hours.
12:00 AM 200 million people in the world
7:48 PM Population doubles 400 million
10:12 PM Population doubles 800 million
11:00 PM Population doubles 1.6 billion
11:36 PM Population doubles 3.2 billion
11:59 PM Population will double 6.4 billion
How large was the world’s population at the 12:00 AM (A.D 1)? At 10:12PM? During those 24 hours, how many times did the worlds population double? How long did it take for the world population to double the first time? Last time?
Population Growth is Worldwide
The example above makes it easy to see that world population has grown rapidly. Even more important ,the rate of growth has increased greatly in modern times.For example , in 1960 the world population was 3 billion. By 200 only 40 years later it had climbed to more than 6 billion people.
Population Birthrate and Death rate
During different historical periods, population grew at different rates. Demographers want to understand why. They know that population growth depends on birth rate and the death rate.
The birthrate is the number of births each year per 1000 people .The death rate is the number of deaths each year per 1000. By comparing birth rates and death rates, demographers can figure out population growth.
For centuries the world population grew slowly. In those years, farmers worked without modern machinery.
Food supplies often were scarce.
Many thousands died of diseases. As a result, although the birth rate was high, so was the death rate. The life expectancy, or the average number of years that people live, was short .A hundred years ago in the United States ,men and women usually lives less than 50 years.
Reasons for Population Growth Today
Today ,things have changed. The birthrate has increased dramatically. The death rate has slowed .As a result , population in most countries have grown very fast. In some countries , the population doubles in less than 20 years. People live longer than ever. In the United States, for example, the average life expectancy for women is about 80 years and for men about 73 years.
Two scientific developments have made this possible .First new farming methods have greatly increased the world’s food supply.
Staring in the 1950s, scientist developed new varieties of important food crops and new ways to protect crops against insects .Scientist developed new fertilizers to enrich the soil so farmers can grow more crops. Scientist also discovered ways to rise crops with less water.
These changes in agriculture are called Green Revolution.
The second set of scientific advancements came in medicine and health .Today, new medicines and types of surgery treat health problems that used to kill people, such as heart disease and serious injuries.
Researchers also have created vaccines to fight diseases such as smallpox, polio and measles, and antibiotics to fight infections .As a result, many more babies are born and stay healthy , and people live many more years.
The challenges of population growth
Today, food supplies have increased and the people live longer. Even, so the people in many countries still face very serious problems .Growing populations use resources much faster than stable population Some nations, like those in Southwest Asia, face shortages of fresh water and energy. In Asia and Africa, food supplies cannot keep up with the growing population. Often these countries do not have enough money to purchase imported food.
Population growth puts pressure on all aspects of life .The population of many countries is increasing so fast that many people cannot find jobs. There are not enough schools to educate the growing number of children .Decent housing is scarce and expensive. Public services like transportation and sanitation are inadequate.
The problems created by rapid population growth are most visible in South Asia .The region is home to about a quarter of the world’s population. According to a World Bank study, South Asia is also home to about a quarter of the world’s poor. Out of every 14 children born. One will die before reaching the age of one.
Rapid population growth also affects the environment. For instance, forest in areas of India and Pakistan are disappearing .People cut the trees to use the wood for building and for fuel. Cutting forests affect s the supply of clean air. Before, tree roots held soil in place. Now heavy rainfall may wash away the soil.
Look at the population changes indicated in the graphs on this page. It shows how rapidly change has occurred in the last 300 years. The Earth’s resources must now be shared by six times as many people than earlier times. All the Earth’s people must work to meet this challenge.
Section 2 review
1. Define
Birthrate
Death rate
Life expectancy
Green revolution
2. Why has the world’s population increased so dramatically in the last four or five decades?
3 .How have science and technology contributed to the growing population?
Critical thinking
4 .Draw conclusions
The world’s population has been growing at fast rate .What are some of the dangers of rapidly increasing population?
Activity
5 .Writing to Learn World hunger is one of the major concerns caused by rapid population growth. Write one or two suggestions to help solve this problem.
SOURCE: Geography Tools and concepts, World Explorer. Pearson Education. Pages 60-63
