Demographic Changes Demographic Transition Model Transitions In World Population

Calculating Population Change Population changes as result of four variables: –Births + immigration = increase –Deaths + emigration = decrease (CBR+I)-(CDR+E)= Total population This equation better suited to study population trends rather than specifics In what ways might geographers use this data?

Demographic Transition Model Used to determine stages of a country’s growth Graphs population, time, birth and death rates (doesn’t account for migration) Used to correlate a country’s progress in technology and society PopPop Stages/Time

Stage 1: Low Growth (High Stationary) Overall Population is sparse High birth-high death= stationary pop Lack of major food surplus keeps population low Super long doubling time ALL WORLD REGIONS UNTIL 17 th C Agricultural Revolution: domesticated plants/animals make for better food sources and lead to transition

Population graph for the first four million years

Stage 2: High Growth (Early Expanding) CDR decreases rapidly (especially people under the age of 5) CBR remains steady Results in natural increase Industrial Revolution –Technology produces and transfers goods –Industry and farming improve Sanitation improvements- examples? Medical advancements- examples? Bangladesh, Nigeria, Pakistan

Stage 3: Moderate Growth (Late Expanding) CBR drops CDR drops but slower than stage 2 decrease NIR is modest CBR drops because of new technologies –People have fewer kids –Medical advances mean less chance of children dying –Economic factors: less farming more urban How does this correlate? –Women become better educated How does this correlate? –China, Brazil, Mexico, India

Entering Stage Three Even though birth rate is falling, population momentum keeps the total population growing.

Stage 4: Low to No Growth (Low Stationary) CBR=CDR (little to no growth) Most European nations in Stage 4 –U.S. moving in this direction Social Customs –Women working –Employed parents need to plan for day care –Entertainment and leisure activities –EXPLAIN! US, Sweden, Japan, Britain

Stage 1Stage 2Stage 3Stage 4 Low growthincr grwthdecr grwthlow/no Birth Rate Death Rate Total Popul ation

Problems with the Model? No "guidelines" for how long it takes a to get from Stage I to IV. Just describes it –Western Euro countries took centuries –Economic Tigers took decades.Economic Tigers Nations that were populated by emigration did not go through early stage Birth rates have fallen below death rates in some areas, should there be a stage V?

PROPOSED FIFTH STAGE: Negative population growth CBR drops to zero-CDR very low-population is slowly dying out (Children of Men) Not enough people in the work force to support programs for the aged (dependency ratio very lopsided) Social programs overloaded-unrest & probable chaos Innovations stagnant Prezi