Population and Migration

AP Human Geography

Population: Unit 2

The “Ecumene”

  • The “ecumene” is the inhabited area of the earth.
  • Today, the only areas that aren’t inhabited are those that are too hot, dry, cold or at high elevations.
  • 3/4’s of the earth’s population live on 5% of its surface (71% ocean)
  • 20% of the earth is too dry
  • Precipitation over 50 inches a year leaches nutrients
  • Permafrost toward the poles
  • High elevations (80% live at less than 1,640 feet elevation)

The World Today: Seven Billion People

  • 90% of the world’s people live north of the equator.
  • 90% live on 20% of the earth’s land.
  • 2/3 live within 500 km (310 miles) of an ocean
  • About 50% of the world’s people are urban (living in or near cities).

Major population clusters:

  • East Asia
  • 20% of humanity (mostly China—third largest land area)
  • About 2/3 rural
  • China—26 cities over 2 million people, 52 with more than 1 million
  • South Asia
  • 20% of humanity (India—second most populous country)
  • 15% of humanity in India alone (about 1 in every 6 people)—concentrated along the Ganges and Indus rivers
  • About ¾ rural
  • Southeast Asia
  • About ½ billion people (100 million on the island of Java alone—Indonesia 4th most populous country)
  • 8% of humanity
  • Mostly rural
  • Europe
  • About 2/3 billion people
  • 11% of humanity (more than 1 in every 10 people)
  • About ¾ urban—less than 20% are farmers
  • Eastern North America (just to give us some perspective)
  • About 120,000,000 (major eastern cities of US & Canada)
  • Just 2% of humanity (US & Canada combined are ~5% of world)

Population Density: Remember, density is a measure of “how many per.”

  • The question is – what are we interested in finding out?
  • Different density measures give us different insights, such as:
  • Level of development
  • Type of economy
  • Clues about population growth, health, status of women, etc.

Different Density Measures: Examples—these can be deceiving because population within a country isn’t distributed

evenly

  • ARITHMETIC DENSITY (“average density”)
  • (total population)/(total land area)
  • US population = ~300,000,000
  • US land area = 9,161,923 km2
  • (299,000,000)/(9,161,923) = ~32.6
  • PHYSIOLOGIC DENSITY (“farmland density”)
  • (total population)/(total arable land area)
  • US population = ~300,000,000
  • US arable land = ~1,650,000 km2
  • (300,000,000)/(1,650,000) = ~181.8

Rate of Natural Increase: CBR – CDR = NI

  • Currently about 1.2% for the world—all-time peak at 2.2%in 1963
  • 80 million being added to the world annually
  • Clustered in LDCs—Africa, Latin America, and the Middle East—Europe is actually negative—most of the world’s additional population lives in countries least able to sustain them

Crude Birth Rate: CBR = (births per year)/(total population)

  • “crude”—focused on society as a whole rather than a particular segment of the population
  • Highest in sub-Saharan Africa and lowest are in Europe

Crude Death Rate: CDR = (deaths per year)/(total population)

  • Notice the similarities in numbers between the MDC’s in Europe and the LDC’s around the world…why would this be?
  • Highest in the world is 19, lowest is 1

Doubling Time: Interest

Simple vs. Compound Interest (Initial amount: $100 Interest: 10%)

  • Conclusion: At 10% it takes less then 8 years for compound interest to double the initial amount. If we continued, we'd find that the amount tripled in 12 years, quadrupled in 15 years, etc.

Doubling Times & Population Growth

  • The rate of natural increase declined between 1950 and 2000–but the number of people added to the world’s population each year has remained fairly steady for about 40 years.
  • At 1.2% doubling time is 54 years—by 2100 there would be 24 billion people—if it drops to 1% the doubling time becomes 70 years
  • Why? Because global populationincreased from 2.5 billion to over 6billion during this time period!

Other Population Measures

Total Fertility Rate (TFR): An estimate of how many children a woman will have during her childbearing years. (roughly

between the ages of 15-49)

  • Assumes women in the future will act exactly as women today do.
  • 2.7 for the world as a whole today—ranges from 6 in some countries to less than two in some European countries

Infant Mortality Rate (IMR): Deaths of infants less than 1 year old, divided by total births per year.

  • (total infant deaths)/(total births) = IMR
  • More than 100 in much of Africa (that’s over 10%)
  • Reflects on a country’s health system
  • Why is the US’s so high given the quality of the medical care?...many can’t afford health care in the US/immigrant populations

Life Expectancy: An estimate of the number of years a child born today can expect to live at current mortality levels.

The Demographic Transition

  • Q: Why do countries have different rates of natural increase and different fertility rates? Why do these rates change?
  • A: The Demographic Transition
  • The demographic transition is a model of how birth and death rates change over time
  • Birth and death rates change because of
  • Changes in the economic system (from traditional to post-industrial)
  • Changes in information about health and health care (sanitation, etc.)
  • Changes in people’s attitudes about family size
  • Demographic Transition Stages
  • Stage 1: Low Growth
  • Most of humanity’s history—NIR was essentially zero because of high birth rates and high death rates
  • Agricultural Revolution—8000 BCE, we see some modest growth due to the birth of agriculture and food surpluses—population still kept in check by famine, war, disease, etc.
  • No country is found in this category today
  • Stage 2: High Growth
  • 1750—Industrial Revolution leads to improvements in manufacturing creating greater wealth and allowing communities to become healthier over time—become more hygienic and improved sanitation
  • CBR remains consistent with stage 1, but the CDR drops drastically—leads to rapid population growth
  • Arrived in Latin America, Asia, and Africa much later than in the West by 1950—medical revolution (penicillin, vaccines, insecticides) arrived and reduced the CDR but without actually the changes in societyresulting in a reduction in the CBR
  • Stage 3: Moderate Growth
  • CBR begins to dropdrastically—CDR may continue to fall but not at the same rate as in stage 2—NIR may still increase but the rate is much smaller
  • People choose to have fewer children because of a change in social custom—may be a delayed reaction to the decreasing Infant mortality rate (IMR)—children are no longer financial assets and living in cities people no longer work on farms, smaller urban dwellings may also discourage as many kids
  • North America and Europe moved into this state in the mid-20th century, Latin America and Asia more recently, and most of Africa not yet
  • Stage 4: Low Growth
  • CBR declines to the point it virtually equals CDR and the NIR approaches zero
  • Zero Population Growth (ZPG)—
  • It takes a Total Fertility Rate (TFR) of 2.1 to sustain the current population—migration may account for some continued population growth
  • Women enter the labor force, access to birth-control all result in reduced CBR
  • Stage 5???—Declining Population
  • Russia and other countries have negative population growth—state sponsored family planning, fear of the future, and pollution have reduced their population

Population Pyramids

  • One way of visualizing how a country is changing (and how it maychange in the future) is by using a population pyramid, a kind of bar chartthat shows the age and sex structure of the population.
  • Sex Ratio—varies among countries—slightly more males than females are born, but males have higher death rates (Europe and North America—95 men:100 women, Rest of the world 102:100—women die during childbirth in LDC’s and so much of the population is young that males haven’t died off yet)
  • What do the countries with the highest numbers of men to women havein common? Almost all are countries where there are enormous numbersof workers in male-dominated industries (oil, fishing). The onlyexception: China
  • What do the countries with the lowest numbers of men to women have incommon? Almost all were part of the former Soviet Union (or weredominated by the Soviet Union), and have experienced social, medicaland economic disruption during the last 20 years. The only exception:Cape Verde, where a large percent of the male population hastraditionally gone overseas, looking for work
  • Dependency Ratio—number of people who are too young or too old to work—0-14 and 65 and older—creates a burden on the rest of society if there are too many—in stage 2 can be as high as half the population vs. stage 4 which is about one-third
  • More than one-fourth of all government expenditures (social security, medical care,) are spent on older people in the US, Japan, Canada, and many European countries

Overpopulation?

  • The only rational wayto define overpopulationis to saythat if the population istoo great for the localenvironment to supportit, a place isoverpopulated.
  • Any other definition isbased on culturalvalues.
  • Carrying Capacity

Thomas Malthus

  • Thomas Malthus (1766-1834), British clergyman and economist—in the midst of the industrial revolution—looked around at the chaos and drew some conclusions
  • Published An Essay on the Principle of Population in 1798.
  • Crucial insight: Population tends to grow faster than the food supply.
  • Arithmetic vs. geometric growth
  • Population growth can be stopped:
  • FAMINE/WAR/DISEASE—higher CDR’s
  • “MORAL RESTRAINT”—lower CDR (no contraception)
  • Was Malthus right?
  • For animal populations – yes.
  • For people – not so far!
  • What did he miss? Contraception (the pill) and improved agricultural techniques and technology
  • Technology—higher-yielding seeds, cultivation of more land, etc.
  • Declining NIR percentages—1990’s1.8percent, today 1.3%
  • “Neo-Malthusians” vs. “Cornucopians”—
  • Neo-Malthusians—modern geographers—argue that there are still instances and regions in which resources are outstripped by population increase…those least able to deal with population increases are increasing most rapidly—resource shortages, ie. energy, water, food
  • Critics:
  • Cornucopians—futurist who believes that continued progress and provision of material items for mankind can be met by similarly continued advances in technology. Fundamentally they believe that there is enough matter and energy on the Earth to provide for the ever-rising population of the world.
  • Marxists—Engels and others would argue that there is plenty to go around if it were distributed equally
  • Boserup, Simon Kuznets, Julian Simon—larger population stimulates the economy
  • Underpopulation—retards economic growth…see Russia begging for ethnic Russians to return home

How do we continue to reduce Natural Increase

  • The rate of natural increase can only decline if either birth rates declineor death rates increase. Of thetwo, most normal people preferthe first – but even this approachis controversial!
  • Reducing birth rates:
  • Economic development (as the economy changes fromtraditional to advanced,countries go through the

Demographic Transition, and birth rates will fall)

Contraception (in many – butnot all – countries, women wish to limit family size).

Two Approaches:“High Mortality=Fast Population Growth”

  • Economic Development—
  • Wealthier communities have more money to spend on education and health-care promoting lower birth rates
  • Women who attend school longer are more likely to be employed and gain economic control—too busy and too inconvenient to have kids
  • IMR declines eventually leading women to have fewer children
  • Women often view having children as a sign of status if they’re provided no alternative way of advancing themselves in society
  • Distribution of Contraceptives—diffusing modern contraceptive methods…”ban-aid solution???”
  • Greater demand than supply available

China vs. India: Population Growth and Change

  • By 2050 India will probably have a population of 1.6 billion, a large percentage of whomwill be in (or entering)

the child-bearingyears.

  • China will probablyhave a population of1.4 billion, but with amuch smallerpercentage in (orentering) the childbearingyears, and amuch older populationoverall.

China

  • One-Child—
  • Financial subsidies, long maternity leave, better hosuing, more land in rural areas if you agree to have one child
  • Gov’t prohibits marriage for men under 22 and women under 20

India

  • 1952—government began to distribute contraceptives, legalized abortion in 1972 (several million per year)
  • 1971—established a controversial program to pay women/men to be sterilized, would then be paid the rest of their lives (in 1976, 8.3 million were sterilized in just a 6 month period)
  • Today: In some places, access to land or housing, pay raises, and other incentives are given to government officials with no more than two children, in some places people are prohibited from holding office if they have more than two

The Epidemiologic Transition

  • At different stages of developmentthere are different processes thataffect the death rate—distinctive causes of death in each stage of the demographic transition model—created by Abdel Omran—epidemiologist, 1971
  • Epidemiology—medical science concerned with the incidence, distribution, and control of diseases that affect large numbers of people
  • Different countries have differentlevels of technologicaldevelopment – and differenthealth problems.
  • Stage 1: stage of “Pestilence & famine”Malthus called these “natural checks” on human population—(“Black Plague”)—spread by migrating infected rats
  • Stage 2: Receding pandemics(“Cholera”)—
  • Pandemic—disease that occurs over a wide geographic area and affects a very high proportion of the population
  • John Snow—1854, mapped cholera outbreak in London to determine their origin—were able to initially close wells to stop the spread
  • Cholera—spread due to sewage getting into the water/well supply—addressed by proper sanitation/sewer systems
  • Stamped out in MDC’s but renewed outbreaks in LDC’s began process of urbanization
  • Stage 3: Degenerative &human-caused diseases (“heartattack & cancer”)
  • Polio and small pox all but stamped out—tetanus, measles, leprosy are gone in MDC’s and declining elsewhere
  • Vaccination
  • Stage 4: Delayed degenerative diseases (“cardiovasculardisease & ontology”)
  • Improving health due to better diet, reduced tobacco and alcohol use, and exercise
  • Stage 5: Emergence &reemergence of infectious &parasitic diseases (“AIDS,”“SARS,” “TB,” “Ebola,” etc.)—West Nile—probably introduced by a bird/animal imported to the US—never found in the Western Hemisphere until 1999 New York City—now a real problem in Texas
  • Reasons for renewal of infectious disease:
  • Transportation and Technology make possible the transmission of infectious disease
  • Resistance to DDT (kills mosquitoes) and antibiotics
  • Continued poverty—don’t have money for treatments for TB and AIDS, or education to stamp it out
  • AIDS— 99% of new cases in the last decade come from LDC’s, 2/3’s of HIV cases are in Sub-Saharan Africa, 9/10’s of the world’s infected children are in Africa
  • Life-expectancy has declined in Botswana, Lesotho, and Swaziland from the mid-50’s in the 1980’s to the mid-30’s today

Migration: Unit 2

Migration: Terms

Mobility: “all types of movement”

  • Circulation: “short term, repetitive, or cyclical movements” vs. migration which is permanent

Migration: “a permanent move to a new location”—type of relocation diffusion

  • Emigration: “migration from”
  • Immigration: “migration to”

Net Migration: “the difference between the number of immigrantsand the number of emigrants”

  • Immigrants > Emigrants: “net in-migration”
  • Immigrants < Emigrants: “net out-migration”

Ravenstein’s 19th Century “Laws” of Migration

  • Most people migrate for economic reasons.
  • Cultural & environmental factors may also be important, but not asimportant as economics
  • Most migrants move a short distance, and stay within a country.
  • Long-distance migrants go to major centers of economic activity (jobs).
  • Most long-distance migrants are males.
  • Most long-distance migrants are adults, not families with their children.

Why Do People Migrate?

PUSH FACTORS encourage them to leave their current location

PULL FACTORS encourage them to come to a new location (usuallya particular place)

  • There are 3 basic kinds of push & pull factors
  • ECONOMIC
  • Jobs (Availability, Advancement)
  • Resources
  • Land (for agriculture, pasturage)
  • Natural resources (minerals, forests, fish)
  • Government Policies (Homestead Act of 1862, etc.)
  • CULTURAL
  • Political Instability
  • War and civil war
  • Prejudice and persecution
  • Refugees—people who have been forced to migrate from their homes and cannot return for fear of persecution, because of their race, religion, nationality, membership in a social group, or political opinion (33 million world-wide as of 2005)
  • Palestinians and Afghans are the two largest groups
  • Columbia and Sudan—are the two largest internal refugees due to political instability—South Sudan was an effort to fix that
  • Political Stability (a pull – not a push!)
  • Forced Migration: Slavery—Please note that slavery is not just of historical interest. It isestimated that more than 20 million people today live in some formof slavery (bonded labor, forced labor, chattel slavery, etc.)—Trail of Tears!!!
  • ENVIRONMENTAL
  • Health and Disease—elderly go to Florida
  • Water (flood, drought, or reliability)
  • Amenities (attractive scenery, beaches, warm winters, etc.)

International Migration: Forced vs. Voluntary—

  • Traditionally, people who move for economic or environmentalreasons are automatically considered to be voluntary migrants.
  • The category of forced migrants is usually limited to two groups:slaves and refugees.
  • Since most people move for economic reasons – most migrants areconsidered to be voluntary.

Refugees

  • Who is a refugee? In the US [under the Immigration and Nationality Act,Section 101(a)(42)]:
  • The term 'refugee' means: (A) any person who is outside any countryof such person's nationality … who is unable or unwilling to return to,and is unable or unwilling to avail himself or herself of the protectionof, that country because of persecution or a well-founded fear ofpersecution on account of race, religion, nationality, membership in aparticular social group, or political opinion, or (B) in suchcircumstances as the President … may specify, any person … who ispersecuted or who has a well-founded fear of persecution on accountof race, religion, nationality, membership in a particular socialgroup, or political opinion.
  • Note that the US is not obligated to accept all refugees, but has agreednot to return people who face persecution to their home country.However, under the 1996 Illegal Immigration and ImmigrantResponsibility Act, foreign nationals who come to this country withoutproper documentation can be summarily expelled unless they expresslystate a fear of return (the “shout rule”). In 2004 the US returned 3,100Haitian and 1,500 Cuban asylum seekers it interdicted on the high seaswhile they were trying to reach Florida (for more information see

Who Is Not a Refugee?