human-population

human-population - Since the early 1800s, the human...

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Since the early 1800s, the human population on Earth has been growing exponentially. The United Nations estimated the Earth 's human population to be 6,800,000,000 in 2009
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Human Population History
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In 1850, the human population reached its first billion. By 1930, it was 2 billion. By 1960, the human population reached 3 billion. Then in 1975, 4 billion, and so on…
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The human population is now growing at a rate of about 3 people/second or 260 thousand/day or 1.8 million per week or 93 million/year
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Each dot represents 1 million people
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The overall rate of population increase depends on the number of births and deaths, but also on the length of generations -- the age at which women have their first baby. For example, if all women had three kids with a 15-year average generation time, the rate of population growth would be 2.7%. If the average spacing were 30 years, the growth would drop in half -- to 1.35%.
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Birth/Death Rates When a substantial proportion of a country's population is young, high population growth rates in a country are to be expected, even if the average total fertility rate is modest. The reason is that so many females are of childbearing age, that even a modest average total fertility rate results in a large number of births.
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Total fertility rate (TFR) - estimate of the average number of children a woman will have during childbearing years In 1995, the TFR was 3.1 children per woman; still far This map shows the average number of children born to a woman during her lifetime. The darker the color, the
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This note was uploaded on 09/06/2010 for the course EE 56244 taught by Professor Kim during the Spring '10 term at UCSF.

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human-population - Since the early 1800s, the human...

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