Week 2 Discussion "Climate Change and Population Control"

lenafinest23

Chapter3.pdf

Home >Social Science homework help >Week 2 Discussion "Climate Change and Population Control"

Chapter 1

Population

Prudent men should judge of future events by what has taken place in the past, and what is taking place in the present.

Miguel de Cervantes (1547–1616), Persiles and Sigismunda

The Changing Population of the World

The population of the world is growing. No one will be startled by that sentence, but what is startling is the rate of growth, and the fact that the present growth of population is unprecedented in human history. The best historical evidence we have today indicates that there were about 5 million people in the world about 8000 bc. By ad 1 there were about 200 million, and by 1650 the population had grown to about 500 million. The world reached its first billion people about 1800; the second billion came about 1930. The third billion was reached about 1960, the fourth about 1974, and the fifth about 1987. The sixth came in 1999 and the seventh in 2011. These figures indicate how rapidly the population is increasing. Table 1.1 shows how long it took the world to add each billion of its total population. A projection is also given for the next billion.

There is another way to look at population growth, one that helps us understand the uniqueness of our situation and its staggering possibilities for harm to life on this planet. Because most people born can have children of their own, the human popula- tion can – until certain limits are reached – grow exponentially: 1 to 2; 2 to 4; 4 to 8; 8 to 16; 16 to 32; 32 to 64; 64 to 128; and so on. When something grows expo- nentially, there is hardly discernible growth in the early stages and then the numbers shoot up. The French have a riddle they use to help teach the nature of exponential growth to children. It goes like this: if you have a pond with one lily in it that doubles its size every day, and which will completely cover the pond in 30 days, on what day will the lily cover half the pond? The answer is the twenty-ninth day. What this riddle

4 Global Issues

tells you is that if you wait until the lily covers half the pond before cutting it back, you will have only one day to do this – the twenty-ninth day – because it will cover the whole pond the next day.

If you plot on a graph anything that has an exponential growth, you get a J-curve. For a long time there is not much growth but when the bend of the curve in the “J” is reached, the growth becomes dramatic. Figure 1.1 shows what the earth’s population growth curve looks like.

The growth of the earth’s population has been compared to a long fuse on a bomb: once the fuse is lit, it sputters along for a long while and then suddenly the bomb explodes. This is what is meant by the phrases “population explosion” and “population bomb.” The analogy is not a bad one. The world’s population has passed

Table 1.1 Time taken to add each billion to the world population, 1800–2046 (projection)

Date Estimated world population (billions)

Years to add 1 billion people

1800 1 2,000,000 1930 2 130 1960 3 30 1974 4 14 1987 5 13 1999 6 12 2011 7 12 2024 (projected) 8 13 2046 (projected) 9 22

Source: UN World Population Prospects: The 2008 Revision

Figure 1.1 Population growth from 8000 BC to 2011 AD

1999

2011

1987

1974

1960

1930

1800

8000 BC

7000 BC

6000 BC

5000 BC

4000 BC

3000 BC

2000 BC

1000 BC

1 AD

1000 AD

2000 AD

B ill

io n

s o

f pe

o pl

Year

Population 5

the bend of the J-curve and is now rapidly expanding. The United Nations estimates the world’s population reached 7 billion in 2011, shooting up from the estimated 2 billion in 1930.

Figure 1.2 shows that the largest growth in the future will be in the less developed countries of the world, with India, Africa, and China leading the way. At the end of the twentieth century about 80 percent of the people in the world lived in the devel- oping countries. During the present century, nearly all of the growth in population will occur in the less developed countries. An ever-larger percentage of the world’s population will be relatively poor. In 1950 about two-thirds of the world’s people lived in the less developed countries. By 2000 this percentage had increased to about 80 percent and the United Nations projects that by 2050 about 85 percent of the earth’s population will be residing in the poorer nations.

Because no one knows for sure what the size of the earth’s population will be in the future, the United Nations gives three projections: a high, medium, and low one, based on the possible number of children the average woman will have. Projections are educated guesses. The United Nations believes the middle projection is the most likely and most authors writing on the subject use that number. The population in the developed regions is expected to slowly grow to 1.3 billion in 2050 from 1.2 billion in 2008, with most of that growth in the United States and Canada due to immigration from less developed countries. The less developed countries are expected to increase from 5.5 billion in 2008 to 8.1 billion in 2050.1 From 2010 to 2050 about one-half of the annual growth is expected to occur in nine countries – India, Pakistan, Nigeria, Ethiopia, the United States, the Democratic Republic of the Congo, Tanzania, China, and Bangladesh. (These countries are listed according to

Figure 1.2 Population growth in less developed and more developed countries, 1950–2050 (projected) Source: United Nations Population Division, World Population Prospects: The 2006 Revision, Medium Variant (2007).

0 1950 1970 1990 2010 2030

(projected)

Other less developed countries

Africa

China

India

Population (billions)

2050 (projected)

More developed countries

6 Global Issues

the size of their contribution to world population growth.) The largest growth is expected in India, which is likely to pass China by 2028 to be the largest country in the world, with 1.5 billion people. At that time India and China will account for about one-third of the world’s population. Figure 1.3 gives the three growth projec- tions by the United Nations up to 2050.

High growth rates will take place in the less developed countries because a large percentage of their population consists of children under the age of 15 who will be growing older and having children themselves. If we plot the number of people in a country according to their ages, we can see clearly the difference between rapidly growing populations, which most less developed nations have, and relatively stable or slowly growing populations, which the more developed nations have. Figure 1.4 shows the difference between the populations of the more developed countries and less developed countries. The age structure of the more developed countries is gener- ally column shaped, while the age structure of the less developed countries is usually pyramid shaped.

Another major change occurring in the world’s population is the movement of people from rural areas to urban areas. Although this is happening throughout the world, the trend is especially dramatic in the developing world, where people are fleeing rural areas to escape the extreme poverty that is common in those areas, and because the cities seem to offer a more stimulating life. Mostly it is the young people who go to the cities, hoping to find work and better living conditions. But all too often jobs are not available in the cities either. These rural migrants usually settle in

Figure 1.3 World population projections to 2050: three scenarios Source: United Nations Population Division, World Population Prospects: The 2008 Revision (2009).

B ill

io n s

0 2000 2005 2010 2015 2020 2025 2030 2035 2040

High 10.5

9.1

8.0

Medium

Low

2045 2050

Population 7

slums on the edges of the big cities. At current rates the populations in these informal settlements will double every 10 to 15 years. It is hard to imagine a city like Calcutta getting any bigger. In 1950, when I visited it, it had a population of about 4 million, and thousands of these people lived permanently on the streets; in 1990 it had a population of about 13 million and an estimated 400,000 lived on the streets.2 If the present rate of growth continues, it will have a population of about 17 million by 2015. Table 1.2 gives the world’s ten largest cities in 1950 and 2000 and the

Figure 1.4 Population by age and sex in developed and less developed countries 2010 (projected) Source: United Nations Population Division, World Population Prospects: The 2008 Revision (2009).

85+ 80–84 75–79 70–74 65–69 60–64 55–59 50–54 45–49 40–44 35–39 30–34 25–29 20–24 15–19 10–14

5–9 0–4

85+ 80–84 75–79 70–74 65–69 60–64 55–59 50–54 45–49 40–44 35–39 30–34 25–29 20–24 15–19 10–14

5–9 0–4

Males

Population (millions), 2010 300 200 100 0 100 200 300

Age DEVELOPED COUNTRIES

Females Males

Population (millions), 2010 300 200 100 0 100 200 300

Age DEVELOPING COUNTRIES

Females

Table 1.2 Ten largest citiesa in the world, 1950, 2000, and 2015 (projection)

Population in 1950 (millions) Population in 2000 (millions)

Population in 2015 (projected) (millions)

New York, US 12 Tokyo, Japan 26 Tokyo, Japan 27 London, UK 9 Mexico City,

Mexico 18 Delhi, India 24

Tokyo, Japan 7 São Paolo, Brazil 18 Mumbai (Bombay), India

Paris, France 5 New York, US 17 Sao Paulo, Brazil 21 Moscow, USSR 5 Buenos Aires, 16 Mexico City, Mexico 20 Shanghai, China 5 Los Angeles, US 13 New York-Newark, US 20 Essen, Germany 5 Calcutta, India 13 Shanghai, China 18 Buenos Aires, Argentina 5 Shanghai, China 13 Calcutta, India 17 Chicago, US 5 Dhaka, Bangladesh 13 Dhaka, Bangladesh 17 Calcutta, India 4 Delhi, India 12 Karachi, Pakistan 15

a Formally called “urban agglomerations” in UN publications. Source: (for 2015 projections) UN Population Division, World Urbanization Prospects: The 2009 Revision

Plate 1.2 Growing cities in less developed nations often have a mixture of modern and substandard housing (United Nations)

Plate 1.1 Rural migrants often settle in urban slums in developing nations (United Nations)

Population 9

The most innovative city in the world: Curitiba, Brazil

Curitiba, Brazil, has been called the most innovative city in the world. City officials from around the world visit Curitiba to learn how this city, with rela- tively limited funds, has been tackling urban problems. By using imaginative, low-cost solutions and low technology, Curitiba has created a pleasant urban life that many cities in the more developed nations have yet to achieve. Here is how the city achieved this.

Transportation The city has made public transportation attractive, afford- able, and efficient. Instead of building a subway, which the city could not afford, it established a system of extended, high-speed buses, some carrying as many as 275 passengers, on express routes, connecting the city center with outlying areas. Many people own cars in Curitiba but 85 percent of the commuters use public transportation. This has reduced traffic congestion and air pollution. There are 30 percent fewer cars on city streets than you would expect from the number of cars owned by its residents.

Trash collection Poor people are encouraged to collect recyclable trash in the areas where they live and turn it in for food. In 1995 the city gave out about 350,000 Easter eggs, 25,000 Christmas cakes, and 2 million pounds of food in exchange for trash. About 70 percent of its trash is recycled, one of the highest rates in the world.

Education Small libraries have been built throughout the city in the shape of a lighthouse. Called Lighthouses of Learning, they provide books (many schools in Brazil have no books), an attractive study room, and, in a tower, a strong light and guard to make the area safe.

Health Curitiba has more health clinics – that are open 24 hours a day – per person than any other city in Brazil.

Environmental education The Free University for the Environment was built out of recycled old utility poles next to a lake made from an old quarry. Short courses on how to make better use of the environment have been designed for contractors, merchants, and housewives. Taxi drivers are required to take a course there in order to get their licenses.

(Continued)

projected ten largest for the year 2015.3 Note that eight of the ten largest cities in the year 2015 are expected to be in the less developed countries – Tokyo and New York are the exceptions – whereas in 1950 only three of the ten were in the poorer countries (Shanghai, Buenos Aires, and Calcutta).

Note also the increased size of the cities. Cities with over 5 million people are sometimes called “megacities.” In 1950 Buenos Aires and Shanghai were the only cities in the developing world with at least 5 million people. By 2005 there were about 60 megacities in the world with the majority of them being in the less devel- oped nations. Many of these cities had vast areas of substandard housing and serious urban pollution, and many of their residents lived without sanitation facilities, safe drinking water, or adequate healthcare facilities.