Population Population GeographyGeography

Population DistributionPopulation Distribution• How population is spread out across

the world• World population distribution is World population distribution is

uneven. uneven. • Places which are Places which are sparselysparsely populated populated

contain few people. Places which are contain few people. Places which are denselydensely populated contain many populated contain many people. people.

Population DistributionHow population is spread out across the world

Causes1. Rivers and lakes (transportation, farming, drink)

2. Flat, fertile soil

3. Adequate rainfall

4. Mild climate

5. Ample natural resources

Effects

1. People live in areas that have those characteristics

2. Some continents have greater populations than others

Population DistributionHow population is spread out across the world

Causes1. Rivers and lakes (transportation, farming, drink)

2. Flat, fertile soil

3. Adequate rainfall

4. Mild climate

5. Ample natural resources

Population DistributionHow population is spread out across the world

Effects1. People live in areas that have those

characteristics

2. Some continents have greater populations than others

Population DistributionHow population is spread out across the world

Causes1. Rivers and lakes (transportation, farming, drink)

2. Flat, fertile soil

3. Adequate rainfall

4. Mild climate

5. Ample natural resources

Effects

1. People live in areas that have those characteristics

2. Some continents have greater populations than others

FactsFacts• 81% live in Asia, North America and Europe -

Northern Hemisphere between 20N and 60N latitude

• This is because of suitable climate and vegetation for dense human population - Warm enough and wet enough to make agriculture happen

• Populations concentrated along coast and river valleys

• Lightly populated regions are in polar zones, heavily mountainous regions and desert regions

Population DensityPopulation Density

The average number of people in a The average number of people in a measurable area.measurable area.Population density is calculated by dividing Population density is calculated by dividing the number of people by area. the number of people by area. Because population is not evenly Because population is not evenly distributed across the land, the number distributed across the land, the number may be misleading for an entire nationmay be misleading for an entire nation

United StatesUnited States

In the 1990 census, the population density In the 1990 census, the population density of the US was 70.3 people per square of the US was 70.3 people per square mile.mile.

However, Alaska has a density of 1 person However, Alaska has a density of 1 person per square mile while New Jersey has a per square mile while New Jersey has a density of 1098 per square miledensity of 1098 per square mile

Physical Factors High Density Low Density

Relief (shape and height of land)

Low land which is flat e.g. Ganges Valley in India

High land that is mountainous e.g. Himalayas

Resources

Areas rich in resources (e.g. coal, oil, wood, fishing etc.) tend to densely populated e.g. Western Europe

Areas with few resources tend to be sparsely populated e.g. The Sahel

Climate

Areas with temperate climates tend to be densely populated as there is enough rain and heat to grow crops e.g. UK

Areas with extreme climates of hot and cold tend to be sparsely populated e.g. the Sahara Desert

Human Factors High Density Low Density

PoliticalCountries with stable

governments tend to have a high population density e.g. Singapore

Unstable countries tend to have lower population densities as people migrate e.g. Afghanistan.

SocialGroups of people want to

live close to each other for security e.g. USA

Other groups of people prefer to be isolated e.g. Scandinavians

Economic Good job opportunities

encourage high population densities

Limited job opportunities cause some areas to be sparsely populated e.g. Amazon Rainforest

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Population GrowthPopulation Growth

The world's population is growing very The world's population is growing very rapidly. rapidly. In In 18201820 the world's population reached the world's population reached 1 1 billionbillion. . In In 19901990 it reached it reached 6 billion6 billion people. people.

Birth and Death RatesBirth and Death RatesThe major reason for population changes, The major reason for population changes, whether in an individual country or for the whole whether in an individual country or for the whole world, is the change in birth and death rates. world, is the change in birth and death rates. The The birth ratebirth rate is the number of live babies born is the number of live babies born in a year for every 1000 people in the total in a year for every 1000 people in the total population. population. Death ratesDeath rates are number of people dying per are number of people dying per 1000 people. 1000 people. When birth rates are higher than death rates the When birth rates are higher than death rates the population of an area will increase. population of an area will increase.

Why has the population Why has the population exploded in the last 150 years?exploded in the last 150 years?

Health ImprovementsHealth Improvements

Over the past 150 years improvements in Over the past 150 years improvements in health carehealth care and and sanitationsanitation around the around the world have led to a drop in the death rate. world have led to a drop in the death rate. While birth rates have dropped in MEDCs, While birth rates have dropped in MEDCs, birth rates are still high in LEDCs. birth rates are still high in LEDCs. Therefore the number of people in the Therefore the number of people in the world has grown rapidly. world has grown rapidly.

Life ExpectancyLife Expectancy

Life expectancLife expectancy is the average age a y is the average age a person can expect to live to in a particular person can expect to live to in a particular area. Life expectancy can be used as an area. Life expectancy can be used as an indicator of the overall 'health' of a country. indicator of the overall 'health' of a country. From this figure you can determine many From this figure you can determine many features of a country e.g. standard of features of a country e.g. standard of living. As a general rule the higher the life living. As a general rule the higher the life expectancy the more healthy (or expectancy the more healthy (or developed) a country is. developed) a country is.

Population PyramidsPopulation Pyramids

The population structure for an area The population structure for an area shows the number of males and females shows the number of males and females within different age groups in the within different age groups in the population. This information is displayed population. This information is displayed as an age-sex or population pyramid. as an age-sex or population pyramid.

Population pyramids of Less Economically Developed Population pyramids of Less Economically Developed Countries typically have a wide base and a narrow top. This Countries typically have a wide base and a narrow top. This

represents a high birth rate and high death rate.represents a high birth rate and high death rate.

Population pyramids of More Economically Developed Population pyramids of More Economically Developed Countries typically have a roughly equal distribution of Countries typically have a roughly equal distribution of

population throughout the age groups. The top obviously population throughout the age groups. The top obviously gets narrower as a result of deaths.gets narrower as a result of deaths.

The horizontal

bars show the percentage of

male and female in each age

group.

1. Which age group has the greatest proportion of people? 2.Which bar includes the students in this classroom? 3. Are there more people in your age group or in the age group below yours?

45-49

A pyramid shows the history of a country's population growth. In the United States from 1945 to 1965, people had larger families. These people are now between the ages of 30 and 50 and are called baby boomers. This pyramid is an example of slow population growth.

Short-term fluctuations often can be traced to Short-term fluctuations often can be traced to such historical events as wars, epidemics, such historical events as wars, epidemics, economic booms, or depressionseconomic booms, or depressionsBaby Boom-after WWIIBaby Boom-after WWIIGreat Depression-decline in birth rate 1930 and Great Depression-decline in birth rate 1930 and 19341934World Wars I and II-deficit of men in GermanyWorld Wars I and II-deficit of men in GermanyThe impact of these events emphasizes the The impact of these events emphasizes the interrelationships among population change and interrelationships among population change and economic, social, political, and health factors.economic, social, political, and health factors.

1.How is Congo's pyramid different from that of the U.S.?

2.Which age group in Congo is the largest?

3.What proportion of the population is in this age group?

There are more people in the younger age groupsAlmost 20%

(9% female and 9% male)

1. Now look at Germany. How is it different?

2. How is it different from Congo?

The age groups are closer to being equal

There is a greater proportion of older people

Why do we need this information?Why do we need this information?

Why would a country 's leaders want to know Why would a country 's leaders want to know the proportion of the population in different age the proportion of the population in different age groups? groups? What difference does the age of the people in What difference does the age of the people in a country make? a country make? What kinds of products do young people use? What kinds of products do young people use? What kinds of services do they need? What kinds of services do they need? What about older people? What about older people? Is it important for a government leader or Is it important for a government leader or planner to know the age of the population they planner to know the age of the population they are serving? are serving?

Young people –Schools, and later, jobsYoung people –Schools, and later, jobsOlder people- retirement systems and Older people- retirement systems and medical facilities medical facilities As a population ages, needs change from As a population ages, needs change from childcare and schools to jobs, housing, childcare and schools to jobs, housing, and medical care. and medical care.

Migration also affects pyramid shapeMigration also affects pyramid shape Most migrants are in the working ages, Most migrants are in the working ages, and often more males than females and often more males than females In some Middle Eastern countries a large In some Middle Eastern countries a large number of men migrated to work in the oil number of men migrated to work in the oil fields, which caused a bulge in one side of fields, which caused a bulge in one side of the pyramid, while it took a "bite" out of the the pyramid, while it took a "bite" out of the pyramid of some of the countries from pyramid of some of the countries from which they came. which they came.

Time to make your own Population Time to make your own Population PyramidsPyramids

We will use a modified pyramid with only 4 We will use a modified pyramid with only 4 age groupsage groupsFirst we will practice with the U.S.First we will practice with the U.S.After we are done, you will get in groups of After we are done, you will get in groups of 4 and graph pyramids of other countries4 and graph pyramids of other countries

US Population by Age 2000 (percent)

AGES MALES FEMALES

0-19 15% 14%

20-39 15% 14%

40-59 13% 13%

60+ 7% 9%

60+

40-59

20-39

0-19

30 25 20 15 10 5 0 5 10 15 20 25 30

Percent of Population

Now get in your Now get in your groups and make groups and make your population your population

pyramidspyramids

PolandPolandHaitiHaitiThailandThailandItalyItalySaudi ArabiaSaudi ArabiaBrazilBrazilAustraliaAustraliaEthopiaEthopiaJapanJapanCanadaCanadaArgentinaArgentinaKenyaKenyaGermanyGermanySouth KoreaSouth KoreaIndiaIndiaNigeriaNigeriaCubaCubaLithuaniaLithuania

EgyptEgyptUnited KingdomUnited KingdomChinaChinaMexicoMexicoDem. Rep. of CongoDem. Rep. of CongoFranceFranceBangladeshBangladeshIranIranIndonesiaIndonesiaIrelandIrelandCyprusCyprusPakistanPakistanSri LankaSri LankaVietnamVietnamRomaniaRomaniaHondurasHondurasPapua New GuineaPapua New GuineaHungaryHungary