Geography Lesson Note for Garde 10... Unit 4 and 5 (1)

Geography Lesson Notes

4.1 OVERVIEW OF WORLD POPULATION GROWTH AND SIZE

A. Global Population Trends

• World population growth surged after World War II, particularly in less developed regions.
• A significant demographic increase occurred:
  • 1 billion added between 1960-1975
  • Another billion by 1987.
• Global population growth breakdown:
  • Increased from 1.6 billion in 1900 to 6.1 billion by 2000.
  • Exceeded 7 billion by 2020.
• Population distribution shifted between 1970-2021:
  • Asia’s share: increased from 58% to 61%
  • Africa’s share: increased from 10% to 13%
  • Latin America and the Caribbean: increased from 8% to 9%
  • Northern America: decreased from 6% (1950) to 5% (1998)
  • Europe: decreased from 18% to 12%.
• Asia remained the most populous continent in 2020, contributing 59.4% of world population, while Africa significantly contributed to global population growth.
• Oceania remained the least populated region with approximated 43 million people.
• Overall, the number of people added to the global population post-1950 exceeds all prior historical growth records.

B. Changes in Fertility and Life Expectancy

• Fertility rates and life expectancy have changed notably over the last seven decades.
  • Early 1970s women: average of 4.5 children per woman.
  • By 2015, fertility rates dropped to under 2.5 children per woman.
  • Global life expectancy increased from 64.6 years (early 1990s) to 70.8 years (2020).
• Despite declining fertility rates, the rate of decline has been slower than that of mortality rates, contributing to ongoing population growth.
  • Advances in medicine, increased living standards, and reduced infant and maternal mortality rates facilitated this growth.

C. Population Size and Growth in Africa

I. Population Size

• Sub-Saharan Africa (SSA) exhibits the world's highest population growth rate at approximately 3% per year.
• Expected rise from 700 million in 1995 to 1.6 billion by 2030 driven by a total fertility rate (TFR) of approximately 6.0 children per woman, which is double the global average.

II. Population Growth

• Population change in SSA much exceeds that of other regions.
  • Africa has emerged as one of the fastest-growing regions globally, driven by interactions of fertility and mortality.
  • Birth and death rates have globally declined; however, Africa's rapid population growth continues unabated.
• Historical context of Africa’s population growth:
  • Population doubled over 700 years (1000-1700 AD), and doubled again in nearly 200 years.
  • Post-1950, population doubling time has shortened to approximately every 25 years due to accelerated growth.
• Calculation of population doubling time uses the Rule of 70, which divides 70 by the growth rate.

D. Examples and Exercises

Example:

• Given Ethiopia’s population at 120 million by 2020 with a growth rate of 2.5% per annum, calculate the years for the population to double.

Exercise:

• A hypothetical country had a total population of 1.4 billion in 2021 with a growth rate of 1.5% per annum. Calculate the years required for its population to double.

E. Factors Responsible for Africa’s Rapid Population Growth

• Interrelated demographic and socio-economic factors contributing to Africa's rapid and consistent population growth from 1950 to 2020 include:
  • High crude birth rates.
  • High fertility rates.
  • Early childbirth practices.
  • Low contraceptive use in many African nations.
  • Declines in infant mortality rates.
  • Declines in maternal mortality rates.
  • Declines in overall death rates.
  • Increase in life expectancy and decline in HIV/AIDS-related deaths.

F. Population Change in Africa

Components of Population Change

• Population change is influenced by three variables:
  1. Fertility (births).
  2. Mortality (deaths).
  3. Migrations (immigration or emigration).
• Population changes can occur through:
  i. Births occurring in an area.
  ii. Deaths of inhabitants.
  iii. Influx of outsiders.
  iv. Outflows of residents.

G. Demographic Balancing Equation

• Population analysis relies on methods to accurately calculate birth rates, death rates, and migration rates, referred to as demographic variables.
  • Natural increase (excess of births over deaths) and net migration (balance between immigration and emigration) affect population changes.
• The Demographic Balancing Equation is used to compute population changes, presented in two forms:
  • End Population: $P_t - P_0 = B - D + I - O$
  • Alternative form:
    $P_t - P_o = NI + NM$
    Where:
  • $P_t =$ Population at the end of the period
  • $P_o =$ Population at the beginning of the period
  • $B =$ Births
  • $D =$ Deaths
  • $I =$ In-migration
  • $O =$ Out-migration
  • $NI =$ Natural Increase (B-D)
  • $NM =$ Net Migration (I-O)

H. Components of Population Change (Figure 4.3)

4.2 AFRICA’S MAJOR DEMOGRAPHIC TRENDS

I. Fertility Patterns in Africa

• Fertility refers to the frequency of childbirth in a human population.

Key Definitions:

• Total Fertility Rate (TFR): Average number of children a woman would bear if she passes through her childbearing years (15-49 years) experiencing current age-specific fertility rates.
• Crude Birth Rate (CBR): Number of live births within a specified geographical area per 1,000 mid-year total population annually is defined mathematically as:
  $(CBR = \frac{Total\ annual\ number\ of\ live\ births}{Total\ mid-year\ population} \times 1000)$

II. Example Calculation

• Hypothetical situation: An African country ‘X’ had 2,407,500 live births in 2020 with a mid-year population of 53,500,000.

Calculation of CBR:

• $(CBR = \frac{2,407,500}{53,500,000} \times 1000 = 45)$
• Thus, Country ‘X’ had 45 live births per 1,000 of the mid-year population in that year.

III. Total Fertility Rate by Region (Table 4.4)

Data (Source: Population Reference Bureau Reports 2019):

• Northern Africa: 2004 (3.4), 2008 (3.0), 2012 (3.1), 2016 (3.4), 2020 (2.9)
• Western Africa: 2004 (5.8), 2008 (5.7), 2012 (5.4), 2016 (5.4), 2020 (5.1)
• Eastern Africa: 2004 (5.7), 2008 (5.4), 2012 (5.1), 2016 (4.8), 2020 (4.3)
• Central Africa: 2004 (6.4), 2008 (6.1), 2012 (5.9), 2016 (6.0), 2020 (5.8)
• Southern Africa: 2004 (2.9), 2008 (2.8), 2012 (2.5), 2016 (2.5), 2020 (2.4)

IV. Current Crude Birth Rate for Africa

• According to UN World Population Data Sheet (2020), Africa's Crude Birth Rate (CBR) is estimated at 33 per 1,000 population. This is notably higher than the standard for less developed countries which averages 20 per 1,000.

V. Crude Birth Rates by Major Regions (Table 4.5)

Data (2020)

• Northern Africa:
  • Sudan: 31/1000
  • Tunisia: 16/1000
• Western Africa:
  • Niger: 47/1000
  • Cape Verde: 18/1000
• Southern Africa:
  • Namibia: 27/1000
  • South Africa: 19/1000
• Central Africa:
  • Chad: 47/1000
  • Sao Tome and Principe: 28/1000
• Eastern Africa:
  • Somalia: 49/1000
  • Ethiopia: 32/1000
  • Mauritius: 11/1000

VI. Current Trends and Influences

• Despite a decline in crude birth rates in Africa, they remain relatively high compared to global standards. Key influencing factors include:
  • Limited access to contraceptives.
  • High levels of poverty.
  • Low status of women.
  • High demand for labor, leading to a larger number of offspring.
  • Cultural attitudes regarding large families as a symbol of virility.
  • Low educational attainment.
  • Traditional and cultural influences on family size.

VII. Future Fertility Trends

• Projections to 2050 indicate that Africa's population could peak at 2.5 billion, equating to 25% of the global population.
• Anticipated decline in overall annual population growth to 2% by 2030 while comparing with other regions:
  • Asia: 1.0%
  • Latin America and the Caribbean: 1.2%
  • Eastern Europe: 0.8%
  • World: 1.5%

VIII. Population Growth Graph (Figure 4.4)

4.3 MORTALITY PATTERNS IN AFRICA

I. Definition of Mortality

• Mortality refers to the incidence of death within a population.
• It's a natural negative factor facilitating a decrease in population size.

II. Measures of Mortality

A. Crude Death Rate (CDR)

• The Crude Death Rate is defined as the number of deaths occurring per 1,000 mid-year total population annually.
• Mathematically expressed as:
  $CDR = \frac{Total\ annual\ death}{Total\ mid-year\ population} \times 1000$

III. CDR Example Calculation

• Hypothetical country: 856,000 deaths in 2020 with a mid-year population of 53,500,000.

Calculation of CDR:

• $CDR = \frac{856,000}{53,500,000} \times 1000 = 16$
• Therefore, the CDR for Country ‘X’ is 16 deaths per 1,000 mid-year population in 2020.

IV. B. Infant Mortality Rate (IMR)

• The Infant Mortality Rate symbolizes the incidence of infant death before the age of one.
• It's typically expressed as a number of infant deaths per 1,000 live births within the same year.
• Defined Mathematically as:
  $IMR = \frac{Total\ number\ of\ infant\ deaths}{Total\ number\ of\ live\ births} \times 1000$

V. IMR Example Calculation

• Hypothetical scenario: a country recorded 5,000 infant deaths and had