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ESS Topic 3 Lesson 4. Key Concepts: Computer simulations, population projection. Assessment Statements 3.1.4. What is a population projection?. RECAP: What factors affecting popn size would we need to take into account?. 2.6. 2.1. 1.7. UN Population Projection.
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ESS Topic 3 Lesson 4 Key Concepts: Computer simulations, population projection. Assessment Statements 3.1.4
What is a population projection? RECAP: What factors affecting popn size would we need to take into account?
2.6 2.1 1.7 UN Population Projection
http://www.learner.org/courses/envsci/interactives/demographics/demog.htmlhttp://www.learner.org/courses/envsci/interactives/demographics/demog.html Choose 2 different countries from the drop-down list. For each country, RUN 3 fertility scenarios: 2.6, 2.1 and 1.7 children per woman Write down the projected impact upon population size growth, and explain why this would occur.
Value of projection models? • Requires 2 data points; easy to analyse. • Identify when / if carrying capacity will be met. • Govts can plan for pressures on resources: housing space, transport, food, water, finance, medical care… • Prepare for the environmental impact humans will have. • Put into place popn policies in advance (POPULATION MOMENTUM)
Possible problems? • Assumptions about levels of fertility and mortality and migration levels. • Based upon current population estimates. • Data in many nations is unreliable. • Smaller / LIC nations given less focus. • Assumptions made regarding age groups and fertility or mortality. • Fluctuating BRs (govt policies) and DRs (new vaccines or diseases eg HIV).
How else could we predict population change? Strengths? and Weaknesses?