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					Global Population Growth

1.   What are the trends in global
     population growth?
2.   Where are the people? How do these
     trends come about?
3.   What is the relationship between
     population, the life course, and the
     character of industrial societies?
4.   What do these population changes
     mean for the way we live our lives?
A crowded world
Trends in Human Population Growth
    GROWTH in the World’s Population

   1830 the world’s population reached ONE BILLION
   1930, just 100 years later the population reached 2
    billion.
   1960 (30 years later) it reached 3 billion
   15 more years later in 1975, it climbed to 4 billion.
   12 years later in 1987, it crossed the 5 billion mark.
   12 years later in 1999 the world’s reached 6 billion
   By 2029, the world’s population is estimated to be
    10.4 billion
Population Growth – A graph
Population Growth: developed
and developing countries
How rapidly is the global population adding a
billion?
Distribution of population growth rates
Rate of change in the growth of the
world’s population
Changes in the rate and absolute
growths in the global population
                     As the figure shows,
                      the rate at which the
                      global population is
                      growing is slowing
                      faster than the absolute
                      increases in the
                      population.

                     Can you explain why?
    Distribution of World’s Population
   East Asia: Eastern parts of China, Japan, the Korean
    Peninsula and the island of Taiwan = 25% of World’s
    Population
   South Asia: India, Pakistan, Bangladesh, and Sri Lanka
    20% of World’s population.
   South East Asia: Islands in the Pacific and Indian
    Oceans Indonesia, Philippines etc 500 million people
   Europe = 15% of the World’s People
   North America = Southern Canada & N.E USA has over
    150 million people
   Sparsely populated Areas include – Deserts, Very cold
    Lands (Arctic & Antarctic regions) and Forest Jungles.
Distribution of World’s People
Continental distribution of global population in
2002

                           Asia = 57%
                           Europe = 16%
                           Africa = 12%
                           South America = 9%
                           North America = 5%
                           Australia = 1%
Distribution of the world’s population
1800 – 2050. www.prob.org/...population...growth...growth.htm
World distribution of population by Latitude
Future increases in population
Thomas Malthus (a British Economist) &
his 1798 essay on Population and
Resources
Malthusian Theory on Population
                Thomas Malthus, wrote in
                1798 that: Population was
                increasing geometrically
                but resource supplies
                were increasing
                arithmetically. He
                predicted that eventually,
                population growth will
                outstrip the supply of
                resources and If
                population growth is not
                controlled voluntarily,
                calamities (starvation,
                diseases, wars) will bring
                population in balance with
                the supply of resources.
THE DEOMGRAPHIC TRANSITION
THEORY
Changes in Birth and Death rates during a
demographic transition
                     Stage 1 – Pre-industrial Stage
                       Agriculture leads to population
                       increase and death rate
                       fluctuates due to epidemics
                     Stage 2 – Early Industrial Stage
                        Improved agriculture expands
                       population but improvement in
                       nutrition lowers death rate
                     Stage 3 – Industrial Stage
                        Education and opportunities for
                       jobs causes decline in fertility to
                       match declines in death rates
                     Stage 4 – Post-industrial Stage
                        Low birth and death rates but
                       birth rates might fluctuate at
                       times
Why developing countries today cannot take
advantage of a demographic transition?
   Lack of trained and skilled personnel (brain
    drain).
   Lack of an essential energy base (coal, oil) to
    provide the energy for development.
   Rapid population growth and poverty creates a
    poverty trap and no savings.
   Lack of financial resources for investment in
    building factories and industries
   Strong competition from already industrialized
    countries
What account for variations in Fertility levels
of females from different societies…1?
   The absence of old age social security payments
    necessitate more child birth
   High Infant mortality compels parents to have more
    children
   Society’s view of children i.e. as a prestige
   Educational opportunities for women
   Carrier (job) opportunities for women
   Religious beliefs (Catholics vrs. Muslims)
   Availability and affordable of family planning and
    birth control services
    What account for variations in Fertility levels
    of females from different societies…2?

 Level of affluence in the society
 Cost of educating and raising
  children
 Average age at marriage

 Urbanization and associated high
  standard of living
 Availability and affordable legal
  abortions for women
    Age structure of a country’s population
   A diagram of the age structure of a
    population is called the Population Pyramid.
   The Pyramid records the proportion (%) of
    the total population available in five-year age
    groups usually known as cohorts.
Constructing a Populating Pyramid
1. Look for a census data which divides the
  total population of a country into males and
  females and also into 5-year age groups
  (cohorts).
    Age structure of a country’s population
    …2
   Classify the population of each sex group
    (males & females) into 5 year age group
    intervals (0-4. 5-9, 10-14 etc. to 85+.).
   Calculate the percentage of the total
    population represented by each of the 5 year
    age groups for a) males and b) females.
   Graph the percentage of the 5-year age
    groups for Males on the Left side of the
    vertical axis of a graph sheet and that for
    Females on the Right.
Dependent and Productive Populations
   The pre-productive age = between 0-14yrs,
   Reproductive age = 15 - 44 years and…
   Post-reproductive age = 45 - 85+
Economic Divisions
A) 0-18 = Dependent class
B) 65 years plus = Dependent class
C) 18-65 years = the Productive class
   Age Dependency Ratio: P0-14 + P65+ X 100
                              P 15-64
Types of population pyramids




1. Nigeria - rapidly growing population, broad-base
2. Australia – stable population
3. Bulgaria – declining population, narrow-base
    What is the relevance of the age-
    structure diagram?
   Shows the occupational structure of a
    nation’s population
   Displays the number of males to females
    (sex ratio) in the population
   Provides clues to present and future trends
    in the growth of the population
   Provides evidence of historical events that
    impacted the population (wars, economic
    booms etc).
    Addressing the population problem –
    INDIRECT methods
 Education and empowerment of women
 More women in the labor force

 Improvements in health and economic
  conditions
 Incentives for increasing or decreasing
  births
 State laws setting limits on child births
  e.g. China.
Addressing the population growth
problem – DIRECT methods

 Abstinence
 Family planning & birth control services

 Legal abortion

 Legal migration (immigration and
  emigration)
 Religious beliefs (e.g. catholic)

				
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posted:2/26/2012
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