1. Why is Global Population Increasing?
Key Issue #2
Why is Global Population Increasing?

2. What does this graphic tell us about world population growth between 1950-2015?

3. 3 Measures of Population Change
CBR - Crude Birth Rate
Total # of live births in a year for every 1,000 people alive in the society
CDR - Crude Death Rate
Total # of deaths in a year for every 1,000 people alive in the society
NIR - Natural Increase Rate
% by which a population grows in a year

4. Natural Increase Rate
To calculate natural increase in a country’s population, subtract CDR from CBR, after converting both numbers to percentages

5. What implications does the information in this map have?

6. What implications does the information in this map have?

7. World NIR Beginning of 21st century = 1.2
Lower today than the peak 2.2 in 1963

9. Doubling Time
The number of years needed to double a population assuming there is a constant rate of natural increase
2000 years ago – world population estimated at 250 million
Took 16 centuries to double to 500 million (1650)
1820 (170 years later) – population doubled to 1 billion
1930 – 2 billion
POPULATION EXPLOSION! Why?
1975 – 4 billion

10. Doubling Time Today world population is doubling in 54 years
About 82 million people annually – still significant

11. J-Curve and S-Curve
J-curve – when the projection population shows exponential growth. This is important because if the population grows exponential our resource use will go up exponential and so will our use as well as a greater demand for food and more.
S-curve- traces the cyclical movement upwards and downwards in a graph.
Carrying capacity- largest number of individuals of a population that a environment can support

13. Population Growth
There are actually four elements that go into determining population growth
1. deaths
2. births
3. immigration
4. emigration

14. TFR - Total Fertility Rate
Average number of children a woman will have throughout her childbearing years (c )
Attempts to predict the future behavior of individual women in a world of rapid cultural change

15. What does this map of TFR show?

16. How can worldwide population increase when so many countries’ TFRs are declining?
2017– worldwide TFR = 2.5
(above replacement level of 2.1)

17. Population Reference Bureau estimates global population will reach 9
Population Reference Bureau estimates global population will reach 9.3 billion by 2050
Rising TFRs in India, Indonesia, Bangladesh, Pakistan, Nigeria

18. Population Growth at Regional & National Scales
Countries and regions go through stages of expansion and decline at varying times
Continuing high growth rates in Muslim countries of North Africa & SW Asia
Saudi Arabia – one of highest growth rates in world
Iran & Morocco – significant declines
Demographers connect high growth rates with low standing of women
Cultural traditions restrict educational and professional opportunities for women and men dominate per custom

19. Population Pyramids
Display percentages of each age group (5 year groups) by horizontal bar whose length represents its share (males to left, females to right)

20. Population Pyramids
Population in a country is influenced by the demographic transition in 2 major ways:
Percentage of population in each age group
Distribution of males and females
Population composition = # of men and women & their ages (also includes marital status and education)

22. Age Distribution
Dependency ratio = number of people who are too young or too old to work, compared to the number of people in their productive years
Divide population into 3 groups
Age 0-14
Age 15-64
Age 65 and older

23. Japan’s Dependency Ratio

25. Sex Ratio Number of males per hundred females
In general, more males than females, but males have higher death rates
Europe & North America 95:100
Rest of world 102:100
USA males under age :100
Women start outnumbering men at age 40
Women comprise 58% of pop over age 65

28. Population Pyramids for Selected Countries1

29. Guest Workers, mainly from South Asia1

30. Guest Workers from India in the Persian Gulf Countries 1

31. Post War Baby Boom and Declining Birth Rate1

32. 1

33. Declining Birth Rate, Emigration, War1

34. Mourning the dead. 1

35. Stable Population Growth1

36. Slow Decline 1

37. High Birth and Death Rates1

38. “Although the Comoros is a poor country, extreme manifestations of poverty such as famine or homelessness are rare. The great majority of people have access to adequate food, clothing, shelter, and, to some extent, water.” 1

39. Slightly Increasing Population1

40. “Increased prosperity as a result of the Celtic Tiger's economic boom in the wake of its 1973 EU membership has led to major changes in Ireland which is no longer traditionally a country of emigration and is receiving substantial numbers of immigrants to fill jobs.” 1

41. Extremely High Birth and Death Rates1

42. Persistent Poverty and Violence 1

43. What do these tell us about the USA?

44. Population Pyramid Homework
Population Pyramid Homework!! (Population Pyramid and projected population, infant mortality rate and total fertility rate)
(Urban Population %, CO2 admissions, population with access to clean water, HIV infection rate)