Chapter 2

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Transcript Chapter 2

Chapter 2
Key Issue 2
Key Issue 2
Where has the World’s
Population Increased?
Population increases QUICKLY in places
 More
people are born than die
 Population
increases SLOWLY in places
Number of births exceed number of deaths
by small margin
Population decreases in places where…
deaths outnumber births
Natural Increase
 Geographers
use 3 measures to examine
population change
 CBR:
total number of live births in a year
for every 1000 alive in society
 CDR:
total number of deaths in a year for
every 1000 alive in society
Natural Increase
 NIR:
Percentage by which population
grows in a year.
Convert CBR & CDR into percentages
of 20 = 2%, CDR of 5 is 0.5%
 Subract CDR from CBR
 2% - 0.5% = ______%
 1.5%
Natural Increase
 2000-2010:
World NIR was 1.2
 Current population is over 7billion
 What will the population be in 2 years?
Natural Increase
 Small
percentage makes HUGE difference
 2006 population:
6.6 billion x 1.2 NIR = 80 million people
(about 1/4 of US pop)
NIR affects doubling time = amount of time
it takes to double a population
At current NIR rate of 1.2, global
population will reach 24 billion by 2100
Natural Increase
 Almost
100% of increased population is in
LDCs: Africa, Asia, Latin America, Mid East
 Exceeds 2% in most LDCs
 0% growth in Europe (negative #)
Natural Population is declining (does NOT
include migration)
Natural Increase
 Most
of world’s additional people live in
countries that CANNOT support them
 Highest
CBRs are in sub-Saharan Africa
(40), lowest in Europe (10)
 TFR: total fertility rate measures average
number of children a woman will have in
her childbearing age (15-49)
 Predicts
future behavior
in Sub-Saharan Africa = 6+
 TFR in Europe = >2
Total Fertility Rate
 In
addition to CDR, IMR and life
expectancy are used to measure
 IMR: annual number of deaths of infants
under 1yrs old, compared to live births
 Highest IMR in sub-Saharan Africa, lowest
in W.Europe
Infant Mortality Rate
exceeds 100 in Africa
 10%
of babies die before 1st bday
 Reflects
a country’s health-care system
 Low
IMRs have well-trained Drs, modern
hospitals, medicine
 Why
does US have higher IMR than
Canada & Europe????
Minorities & poverty often cannot afford
good healthcare
Life Expectancy
 Measures
average number of years a
newborn infant can expect to live
 More favorable in wealthy countries (W
Europe), lower in poor countries (Africa)
 Western Europe = 70s
 Sub-Saharan Africa = 40s
MDCs vs LDCs
 Natural
Increase Rate
 Crude Birth Rate
 Total Fertility
 Infant Mortality
 Life Expectancy
ALL follow similar trends!!!!
Crude Death Rate
 Does
not follow familiar pattern
 Which has higher CDR?
US or Mexico?
Denmark or Mongolia?
 Populations
are at different states in the
Demographic Transition (Key Issue 3)
Key Issue 2 Summary
 Virtually
all the world’s natural increase is
concentrated in the relatively poor
countries of Africa, Asia and Latin
America. In contrast, most European and
North American countries now have low
population growth rates and some are
experiencing population declines. The
difference in natural increase between
MDCs and LDCs is attributable to
differences in CBRs rather than in CDRs
What is crude birth rate?
 Total
number of live births in a year for
every 1,000 people
With a partner…
 Analyze
each map in Key Issue 2
 Each of you comes up with a question
comparing the data.
 Ask each other your questions to be
What is crude death rate?
 Total
number of deaths in a year for every
1,000 people alive in the society
What is NIR?
 The
percentage by which a population
grows in a year
 (subtract CDR from CBR)
What is the NIR today?
 1.2
for the first decade of the 21st century
When did global NIR peak?
 1963
with a peak of 2.2%
About how many people are
being added to the world’s
population each year?
 About
80 million people
Define doubling time
 Number
of years needed to double a
 (assuming a constant rate of natural
In what world regions is most
growth occurring?
 Clustered
in LDCs
 Africa, Asia, Latin America & the Middle
 NIR exceeds 2%
 Negative NIR in Europe
Define total fertility rate
 The
average number of children a
woman will have throughout her
childbearing years (roughly ages 15 to 49)
Define infant mortality rate
 The
annual number of deaths of infants
under 1 year of age compared with total
live births
Define life expectancy
 Measures
the average number of years a
newborn infant can expect to live at
current mortality levels