Overpopulation Global Issue Presentations 2013 2014 What is
Overpopulation Global Issue Presentations 2013 -2014
What is overpopulation? What is the issue? “Man begets, but land does not beget” -Cecil Rhodes • Increasing population • Decreasing resources • Population density • Population is higher than the carrying capacity
The Issue • The world population is increasing along with the average life expectancy. • Life Expectancy • 76 – 2045 -2050 • 82 – 2095 -2100 • 89 – 2100 in developed nations (World Population Prospects: the 2012 Revision) United Nations
Statistics 7 billion – October 31 st 2011 (United Nations) Growth rate: • Worldometers – 1. 1% • CIA World Factbook (2012) – 1. 095% +80 million per year Growth rate peak – 2. 19% in 1963
Statistics
Previous milestones • • 1 billion – 1804 2 billion – 1927 3 billion – 1960 4 billion – 1974 5 billion – 1987 6 billion – 1999 7 billion – 2011
Sigmoid Population Growth
Human Population Growth Source: Worldometers. info
Predictions (United Nations) • +1 billion in the next 12 years • 8. 1 billion – 2025 • 9. 6 billion – 2050 Developing regions 5. 9 billion – 8. 2 billion (2013 -2050) • China and India: 1. 45 billion (2028) • 50% of population growth: Africa • Stabilize at 10 billion - 2062
Mathematics • Carrying capacity – 10 billion (2062) • +75 – 80 million per year • Current population 7 billion • 75, 000/7, 000, 000 = 0. 0107 x 100 = 1. 07% • 80, 000/7, 000, 000 = 0. 0114 x 100 = 1. 14%
Exponential Growth and Decay • Future Population = N=N 0 ekt • Time = • Rate =
Variables Explained • • • ln = natural logarithm: log to the base e e = an irrational number (2. 7182818…) (Euler) t = time k or r = growth rate (births – deaths) N = future population N 0 = initial population
Calculations Finding the time that the population will reach 10 billion (carrying capacity). 10=7 e(0. 011)(t) 1. 429=e(0. 011)(t) ln(1. 429)=ln(e(0. 011)(t)) ln(1. 429)=0. 011 t ln(1. 429)/0. 011 = t t ≈ 32. 452 Property of Logarithms: ln(ex) = x
Verifying Calculations • Future population = N=N 0 ekt 10 = 7 e(0. 011)(32. 452) = 10. 003 Future population Current population (billions) Growth rate Time (from previous calculation)
UN Estimates UN – 2062 -2013 = 49 years N=N 0 ekt 7 e(0. 011)(49) =12 billion ln(10/7)/49=0. 00727 If the population will reach 10 billion in 49 years, the average growth per year will be 0. 7%
- Slides: 15