Transcript Chapter 2
Chapter 2 Population Key Issue 2 Key Issue 2 Where has the World’s Population Increased? Population increases QUICKLY in places where…. More people are born than die Population where…. 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 CBR of 20 = 2%, CDR of 5 is 0.5% Subract CDR from CBR 2% - 0.5% = ______% 1.5% NIR 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) NIR in LDCs Natural Increase Most of world’s additional people live in countries that CANNOT support them Fertility 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 TFR future behavior in Sub-Saharan Africa = 6+ TFR in Europe = >2 Total Fertility Rate Mortality In addition to CDR, IMR and life expectancy are used to measure mortality 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 IMR 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!!!! MDCs vs LDS 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 answered 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 population (assuming a constant rate of natural increase) In what world regions is most growth occurring? Clustered in LDCs Africa, Asia, Latin America & the Middle East 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