aims: 1. to calculate population momentum and consider its impacts. 2. to critique choropleth maps

AIMS: 1. To calculate Population

Momentum and consider its impacts.

2. To critique Choropleth maps.

Population Momentum and World Population Growth

As we have seen, global fertility is declining.

HOWEVER, before the rate of natural increase declines, there is a lag period.

This is because children and youths who have already been born have not yet met their childbearing years.

The population has momentum to keep growing.

POPULATION MOMENTUM is when popn continues to grow even after the replacement level of fertility has been met.

High percentage of popn at or before childbearing age.

Population Momentum Factor (PMF)

PMF

There is positive momentum in the population which will lead to further growth.

Natural increase is not contributing to population growth.

The is negative momentum, with a high probability that the population will decline in size.

Accounting for PMFNIGERIA

0.043 X 47 = 2.021

This is fairly typical for African nations (short life expectancies but continued growth because of high fertility).

VIETNAM

0.017 X 73 = 1.241

Vietnam has seen rapid economic development since 1990. Large decline in popn fertility (popn continues to grow because of increase in life expectancy- better living standards).

JAPAN

0.009 X 82 = 0.738

Declining popn (decreasing BR and increasing LE). Large elderly popn supported through income taxes.

Choose 3 countries and calculate their PMF. Try to choose 3 that will contrast nicely.

AS WORLD POPULATION GROWTH SLOWS, THIS DOES NOT MEAN THAT WORLD POPULATION WILL DECLINE,

MERELY THAT IT WILL GROW AT A SLOWING RATE OF INCREASE.

Growth is getting smaller, not population size.

Global Population Density(persons per square kilometre)

Australia: concentrated along the

South-East coast

Egypt: along the Nile River valley

China: Eastern half of the country

What are some of the problems associated with using

Choropleth Maps?

What factors affect Popn density?

DESERT

MOUNTAINOUS

VERY COLD

80% popn