1. 1 Increasing Human Population The Greatest Environmental Problem Spring 2012, Lecture 2

2. 2 US Census Bureau Population Estimate Click link below to see Latest Census Bureau Estimate of U.S. and World Populations United State Population Clock World Population Clock

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4. 4 United Nations Population Division – 2012 Estimates YearPopulationYearPopulation 19502 529 22920056 506 649 19552 772 98220106 895 889 19603 038 41320157 284 296 19653 331 00720207 656 528 19703 696 18620258 002 978 19754 076 41920308 321 380 19804 453 00720358 611 867 19854 863 29020408 874 041 19905 306 42520459 106 022 19955 726 23920509 306 128 20006 122 770 In thousands

5. 5 2050 Population Estimates Year of Estimate Low variantMedium variant High variant Constant fertility variant 20027 408 5738 918 72410 633 44212 753 513 20057 679 714 9 075 903 10 646 31111 657 999 20087 958 779 9 149 984 10 461 08611 030 273 20128 112 191 9 306 128 10 614 31810 942 544 In thousands

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8. 8 Thomas Malthus (1798) “An Essay on the Principle of Population” Populations grow geometrically while supporting resources grow arithmetically Population, if not purposefully checked (“preventative checks”), would outpace resources and lead to unplanned “positive checks” that would return population to sustainable levels

9. 9 Significant Developments and Human Population

10. 10 Recent Population Explosion Detailed look at the last thousand years

11. 11 Global Fertilizer use Crop Yield and Fertilizer Input “Green revolution”: high-yielding crop varieties chemical fertilizers pesticides irrigation mechanization

12. 12 Humans Have: Transformed or degraded 39-50% of the Earth's land surface Increased atmospheric CO 2 concentration by 40% Overexploited or depleted 22% of marine fisheries 44% more are at the limit of exploitation

13. New South Wales, Australia 13 Figure shows the trend in the total catch for marine fisheries in NSW since 1984–85.

14. 14 Changes Due to Man About 20% of bird species have become extinct in the past 200 years, almost all of them because of human activity Man uses more than half of the accessible surface fresh water On many islands, more than half of plant species have been introduced by man On continental areas, man has introduced 20% or more of the plant species present

15. 15 Human Activities Over 50% of terrestrial nitrogen fixation is caused by human activity Use 8% of the primary productivity of the oceans (25% for upwelling areas and 35% for temperate continental shelf areas)

16. 16 Changes Due To Man

17. 17 Population and Availability of Renewable Resources Source: Postel, S. "Carrying capacity: Earth's bottom line." State of the World, 1994. 19902010 Total Change (%) Per Capita Change (%) Population (millions) 5,2907,03033 Fish Catch (million tons) 8510220-10 Irrigated Land (million hectares) 23727717-12 Cropland (million hectares) 1,4441,5165-21 Rangeland and Pasture (million hectares) 3,4023,5404-22 Forests (million hectares) 3,4133,165-7-30

18. 18 Regional population patterns: Population density Consortium for International Earth Science Information Network.

19. 19 Doubling Times World 40 years Africa 23 years Kenya (fastest)20 years Latin America 30 years Asia 36 years

20. Doubling Time Map - 2000 20

21. Worldwide Fertility, 2005 21 Children per woman

22. 22 Reduction in Childhood Death Rates DDT used against mosquitoes that transmit malaria Childhood immunization used against cholera, diphtheria, etc. Antibiotics used against bacterial infections

23. Demographic Transitions 23 When a country moves from stage 1 of the demographic model to stage 2, a population explosion occurs This transition occurs when technology and medical care improvements decrease a countries death rate dramatically while the birth rate stays the same; this causes the natural rate of increase to increase rapidly

24. 24 Demographic Transition -Sweden “Rate of Natural Increase”

25. 25 Demographic Transition -Mexico “Rate of Natural Increase”

26. 26 National Age Structures The proportion of individuals in different age groups has a significant impact on the potential for future population growth Mexico – large fraction of young people likely to reproduce in the near future Sweden – even distribution of population through all age groups, and many people beyond prime reproductive years United States – even distribution except for bulge due to post WWII baby boom

27. 27 Age Structures Each horizontal bar is a five-year cohort Blue = pre-reproductive, yellow – reproductive, and orange – post- reproductive

28. 28 People over 100 years old in U.S. 4,000 in 1970

29. People over 100 years old in U.S. 79,086 in 2010 29

30. People over 100 years old in U.S. 30 Projected 597,547 thousand in 2050

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32. Trends in U.S. Population 32

33. 2008 Population Projections 33

34. 34 Global Income Distribution, 1960 - 1989 Share of Global Income Going To: Year Richest 20%Poorest 20 % Ratio of richest to poorest 196070.22.330 to 1 197073.22.332 to 1 198076.31.745 to 1 198982.71.459 to 1 Source: United Nations Development Programme, Human Development Program, 1992 (New York, Oxford University Press, 1992)

35. Global Income Distribution Graphic 35

36. Global Wealth Pyramid, 2011 36

37. Food Distribution Animation 37 http://vimeo.com/moogaloop.swf?clip _id=8812686

38. China - 20% of world’s population Potential for rapid population growth 2000: 1,263,637,531 38

39. 39 China: "one-child-per-couple" policy since 1979 Rewards for having only one child: grants, additional maternity leave, increased land allocations. Children get preferential treatment in education, housing, and employment. Couples punished for refusing to terminate unapproved pregnancies, for giving birth when under the legal marriage age, and having an approved second child too soon. Penalties include fines, loss of land grants, food, loans, farming supplies, benefits, jobs and discharge from the Communist Party. In many provinces sterilization is required after the couple has had two children.

40. 40 China’s Population Policy Children per woman: 1970: 5.01 1995: 1.84 Population still growing! Population in 2000: 1.3 billion Projected for 2025: 1.5 billion Use of abortion Forcible abortions and sterilization Infanticide Criticisms:

41. China 2025 Approaching stabilization 2025: 1,394,638,699 41

42. China 2050 Possible decline in population 2050: 1,303,723,332 42

43. 43 2000: 1,006,300,297 India

44. 44 India 2025 2025 predicted: 1.396.046.308 The base is narrower than the top

45. 45 India 2050 2050 predicted: 1,656,553,632 A definite “baby-boom” shape Note disparity male/female numbers

46. 46 U.N. Conference on Population (Cairo, 1994) "Programme of Action" (182 nations) Goal: to stabilize human population at 7.8 billion by 2050 1. Provide universal access to family-planning and reproductive health programs. 2. Recognize that environmental protection and economic development are not necessarily antagonistic. Promote free trade, private investment and development assistance. 3. Make women equal participants in all aspects of society - by increasing women's health, education, and employment. 4. Increase access to education. Provide information and services for adolescents to prevent unwanted pregnancies, unsafe abortion, and the spread of AIDS and sexually transmitted diseases. 5. Ensure that men fulfill their responsibility to ensure healthy pregnancies, proper child care, promotion of women's worth and dignity, prevention of unwanted pregnancies, and prevention of the spread of AIDS and sexually transmitted diseases.

47. 47 United Nations Population Fund (UNFPA) Programs to improve: Pre- and post-natal mother's health Access to voluntary family planning programs and contraception STD and HIV education and prevention U.S. funding withheld for many years because of UNFPA’s support of China’s policies U.S. funding restored for F.Y. 2000 at level of $25 million

48. 48 Slowing Population Growth The HIV epidemic is measurably slowing population growth Nowhere is this more evident than in sub-Saharan Africa, a region of 800 million people, where the epidemic is spiraling out of control If a low-cost cure is not found soon, countries with adult HIV infection rates over 20 percent, such as Botswana, South Africa, and Zimbabwe, will lose one fifth or more of their adult population to AIDS within the next decade

49. 49 Slowing Population Growth When the United Nation's demographers did their biennial update of world population numbers and projections in October of 1998, they reduced the projected global population for 2050 from 9.4 billion to 8.9 billion – in 2009, it is 9.1 billion Of this 500 million drop, two thirds was because of falling fertility - that's the good news The bad news is that one third of the fall was the result of rising mortality from AIDS