POPULATIONS BY THE NUMBERS. 10,000 yrs ago- 5 million Growing Exponentially 1930- 2 billion 1975 – 4 billion 2011 – 7 billion 2050 – 9.5 billion. What does it mean to grow exponentially?. Youtube. The most important video you’ll ever see
growth rate = CBR-CDR
If there were 20 people born per 1,000 people and 8 deaths per 1,000, the global population growth rate would be 1.2%
20-8 OR 20-8 x100
In 2011, the population growth rate of the ….
world was 1.09%
Zimbabwe = 4.3%
Japan = -0.1%
US = 0.9%
India = 1.3%
growth rate 10
Population Growth Rate we take immigration and emigration into account.
Fig. 11.3, p. 240
n = 70/r
rate # of people in pop
A TFR of 2.1 for a developed country suggests that the country is at replacement-level fertility and thus the population is stable.
So, X= 8,600 people/year
Since there is no growth due to biological replacement and a net migration of 8,600 people, the rate of increase is
8,600 people/year = 0.2%
How many years will it take the population to double at this rate?
__CBR-CDR__14 = 1.4%
70/1.4 = 50 years
50 years + 2010 = 2060
26,804 people x 0.386 mi2 = 10,346 people
1 mi2 1 km2 km2
The population of Atlanta is 420,003 and covers an area of 131 square miles.
Calculate the density of the population in
in mi2 and km2
420,003 people = 3206 people/ mi2
3206 people x 0.386 mi2
mi2 1 km
= 1238 people/km2
10,346 people/mi2 = 3.2 times
3,206 people/ mi2
States by density: New Jersey, Rhode Island, Massachusetts population density. With an area of 3/4 of a square mile and a total population of 32,000, Monaco has a density of almost 43,000 people per square mile.States by population: California, Texas, New YorkCities by population: New York, LA, Chicago
“The Lily Pond Parable” from EcoFuture population density. With an area of 3/4 of a square mile and a total population of 32,000, Monaco has a density of almost 43,000 people per square mile.
1. If a pond lily population doubles every day, and it takes 30 days to completely cover a pond, on what day will the pond be ¼ covered?
2. If a pond lily population doubles every day, and it takes 30 days to completely cover a pond, on what day will the pond be ½ covered?
3. Does the size of the pond make a difference?
4. What kind of environmental consequences can be expected as the 30th day approaches?
5. What will begin to happen at one minute past the 30th day?
6. At what point (what day) would preventative action become necessary to prevent unpleasant events? Explain your reasoning.
A. The CBR of a country is 35 and the CDR is 8. Calculate the population growth rate.
B. The population of a city is growing at a rate of 1.7%. It currently has 100,000 people. What will the population be next year?
C. A small country of 600,000 people has 15,000 immigrants and 2,500 emigrants. They also experience 8,000 deaths and 5,500 births. What is the growth rate of this country?
D. How long will it take a population to double if the growth rate is 1.1%