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Overpopulation / Overconsumption Humans have inhabited the planet for more than 150,000 years. During most of that time their numbers have remained below.

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Presentation on theme: "Overpopulation / Overconsumption Humans have inhabited the planet for more than 150,000 years. During most of that time their numbers have remained below."— Presentation transcript:

1 Overpopulation / Overconsumption Humans have inhabited the planet for more than 150,000 years. During most of that time their numbers have remained below two million and their impact on the planet and other living creatures has remained well below sustainable levels. For most of those years the lack of modern technologies ensured that human activity could not seriously damage the planet in any major way. Early humans lacked modern methods of birth control, and we have little reason to think that they did much to limit the size of their families. The major forms of population control were famine, war, disease, accidents, acts of nature, and acts that we would now call homicide. But since the 1800s both human populations and the use of new technologies have increased geometrically. Over seven billion people now inhabit the earth, and the effect of activities by the wealthiest portions of that population can now be detected even where people do not live. The following pages show several consequences that have resulted from human populations growing larger and more affluent.

2 Recent growth explosion of people and consumption rates Since the 1800s world population has surged 700%. But Wikipedia estimates that since 1800 Gross World Product (the combined gross product of all the nations in the world has grown from $175 billion to $71,830 billion in 2012 U.S. dollars, a growth rate of 41,000%

3 Consequence 1: What are the worlds deforestation and arid soil defoliation rates? Tropical rainforests are being reduced by over 80,000 acres per day. If planting is delayed until erosion occurs, these lands become permanently barren. What are the causes of massive deforestation and arid soil defoliation? Seven billion people needing lumber, wood products, building sites and farmland. Overgrazing in arid climates causes permanent desert expansion (called desertification). Plowing where sources of irrigation water cannot keep up with demand also causes desert expansion.


5 What are the consequences of massive deforestation and arid soil defoliation? Deforestation can cause topsoil loss. About half of the worlds non-forested topsoil has been lost to erosion, salt buildup, and other human activity. Flooding, such as the great flood of Thailand in 2011, results from the water retention benefits lost when forests are removed. Water reserves run dry sooner after rains. Less water for irrigation and urban areas. This also often leads to more forest fires. Burning forests adds CO 2 and other pollutants to the air. Loss of forests slows conversion of CO 2 -laden air back to normal air.

6 Consequence 2: Author Lester Brown says the prices of vital food staples (grains, corn, and rice) have doubled since 2007.

7 What has been causing this? Half of the worlds people live in 18 nations where irrigation water sources are in rapid decline as the demand for water increases. Harvests have either peaked or are falling in most of these nations. Overgrazing in arid climates has caused massive desertification. Poor farming methods and hillside farming has caused soil loss. Degraded top soils reduces farming yields. Loss of glaciers, earlier melt-off of snow-capped mountains, and the over-pumping of groundwater aquifers means less irrigation water at a time when average farmland temperatures are rising and droughts are more frequent. Each 1º C increase of average annual temperature reduces farm outputs 10%.

8 Continued: Causes of vital food staples (grains, corn, and rice) having doubled since 2007 The diversion of food staples to ethanol production (32% of grain plus large amounts of corn) has driven up prices and caused food shortages in poor nations. The diversion of grain staples to meat production drives up prices of life- sustaining staples for the worlds poorest people. Urbanization generally occurs where farms once existed. 8,000 square miles of farmland per year are lost to urban sprawl. The U.S. has paved a land mass equal to the size of Georgia. Poor farmers are losing traditional farmlands to wealthy interests. The World Bank estimates that 140 million acres of mostly African and Asian farmlands have gone to such land grabs. That exceeds the amount of U.S. cropland used for wheat or corn.

9 What are the consequences of food prices doubling? Hunger rates have recently quadrupled in poor nations. People who were spending 30% of their incomes on food saw prices double in just five years. The land grabs noted above prevent many thousands of subsistence farmers from growing their own food. Malnourished children experience stunted mental and physical development. Wars and insurrections are on the rise in the areas most affected. Note that almost all of the Arab Spring uprisings have occurred in lands where basic food staples have doubled in price. New leaders will face the same shortages. Lester R Brown, Full Planet, Empty Plates, WW Norton & Co., New York, Free download

10 As food prices spike, people revolt. Incidents of civil or societal unrest in North Africa and the Middle East (shown in red) show a strong correlation between food price spikes and societal instability.

11 Consequence 3: What pollutants get dumped into our air, land, and waters; what damage do they do; and what population-related factors cause this?

12 Some chemicals that have been dumped into our air, land, and waters include: – CFCs cause depletion of the ozone layer. – Mercury causes madness, loss of body functions and horrific deaths. – Cadmium causes decalcification and kidney damage. – Lead poisoning affects brain functioning. – DDT kills wildlife, is a carcinogen at low doses, and can kill people in large doses. – Phthalates from plastics cause reduced sperm counts and malformed sex organs. – Nation-wide findings of CR 6 in well water leads to stomach cancer – New pesticides have threatened the survivability of bees, monarch butterflies and other valued species. – Nitric and sulfur oxides in smoke damage plant life. They contribute to acid rain, which kills trees and lake wildlife. – CO 2 and other greenhouse gases causes water acidification and climate change.

13 Population-related factors that cause air and water pollution: Burning fossil fuels by the millions of tons Burning anything laced with (or painted with) chemicals. Garbage (land fill) burning or seepage. Improper toxic waste disposal (especially in poor nations) and other chemical discharges, such as Freon leakage form refrigeration units. Farming chemicals. Farming runoff Vehicle coolant and lubricants pollute roadway runoff Boat waste cast offs and bilge emissions

14 What are the consequences of dumping pollutants into our air, land, and waters? Smog laced with chemicals and cancer- causing carcinogens in densely populated areas and developing-nation cities causes asthma, allergies, cancer, and lung disease. Water pollution, especially near land runoff areas, can have many toxic effects. In poor nations unsafe drinking water kills millions of children. Scientists have measured steady world-wide increases of several greenhouse gasses. They suspect these gasses are the cause of many current climate aberrations and water acidification. If their worst-case predictions hold true, the effects will be substantial and difficult to reverse.

15 Consequence 4: By what percentages have breeding stocks of the worlds most frequently eaten wild fish been depleted and why? Between 70 and 90 %, depending on the popularity of the fish and other factors. When the stocks of one popular fish species collapse, the fish industry begins exploiting another species.

16 What is causing depletion of the breeding stocks of the worlds most frequently eaten wild fish? The global fishing fleet is 2-3 times larger than what the oceans can support, and it uses highly efficient methods that leave few breeding fish for replenishment. Only 10% of the normal number of large fish (tuna, swordfish, marlin, cod, halibut, and flounder) remain in the sea (Journal Nature). There is no place left in the world where man can legally fish that is not being exploited. The use of drag-netting and other activities damage breading habitats, such as reefs and estuaries. Water pollution, especially near land runoff areas, causes dead zones near the mouths of many large rivers.

17 Consequence 5: What percentage of the worlds reefs are classed as dead or near to fatally degraded, and what population-related factors have caused this? Over 1/3, including much of Australias Great Barrier Reef Causes: Overfishing, which allows reef-destroying starfish, algaes, and other damaging species to spread without natural enemies Acidity due to excess CO 2 absorption Abnormally high water temperatures Drag-netting, dynamiting, and other physical insults Water pollution, especially near land runoff areas

18 Reef damage due to human activity

19 Consequence 6: What is the species extinction rate? Why does this matter? What population-related factors cause this? Every 20 minutes, the world adds over 3,000 human lives but loses one or more species of animal or plant life - at least 27,000 species per year. (Source: PBS). At the present rates, as many as 20% of the world's 7-15 million species could become extinct in the next 30 years. Causes: Habitat destruction Pesticides and pollutants Overhunting Climate change Non-native species introduction


21 Why does it Matter? Many species serve a vital function in balance of nature, e.g., controlling the spread of pest species Many species have unique genes that can be used to improve the strains of valuable plants and animals or unique properties used by the pharmaceutical industry. Some species are valued for their beauty or other features. Are we also vulnerable to these factors? In what ways do the same factors that kill other species also damage our species? The disappearance of species may be like the canary in the coal mine – a warning of growing toxicity. We may depend on the services provided by lost species in ways we do not appreciate.

22 Other Consequences of overpopulation : Pressure to expand, flee or emigrate, but no frontier lands left to accommodate settlers or refugees. Cities of over 20,000,000 people, most of them living in slums or favelas. Poor cities with >10 million people have serious problems with water, waste disposal, transportation, disease control, crime, housing, and the quality of life for most people. When cities double in size, the problems more than double. Competing claims for land, water, and fish resources that can lead to war and threats of war Waste disposal problems where land appropriate for landfills becomes further from the cities and harder to obtain Non-renewable resource depletion, e.g. fuels, metals, and minerals. As these commodities grow scarcer, they become more expensive and they will eventually become unavailable for future generations.

23 Negative Consequences: Can falling birthrates cause any negative consequences? Having a lower ratio of working adults to retired people will make the burdens of elder care fall on a smaller number of worker/taxpayers (a concern referred to as rising dependency ratio.) How serious is this problem? Falling birthrates could help to resolve more menacing population problems. Nations that need more working-age people can relieve the pressures on overpopulated nations by inviting foreign guest workers to fill their workplace shortages. However, nations with falling populations must first find jobs for their own young people.

24 How serious are the problems related to falling birthrates? (continued) In Italy and Spain, where birthrates have recently plummeted, over 20% of the people are unemployed and 50% of recently graduated young people cant find work. Lack of work opportunity may explain why this generation of young adults is having fewer children. The world has no frontier lands left to settle refugees. But refugees can be trained to take care of elderly people and do other jobs in affluent nations. Calling for people to have more children in an overpopulated world resembles calling for war to stimulate a stagnated economy. In both cases, the proposed solution has worse consequences than the problem being addressed.

25 What is the current world population? What is the forecast for population growth? The current population exceeds 7 billion. Estimates range from billion by 2050, peaking at from billion after that. U.N. demographic projections show the world population growing to 9.3 billion by 2050 or 290,000 new people per day. The birthrates that raised the world population from 6-7 billion in just 13 years would lead to 10 billion by 2050.) However, the CIA World Factbook shows birthrates falling recently, enough to slow down, but not reverse, the world- wide growth trend. Lester R Brown, Full Planet, Empty Plates, WW Norton & Co., New York, (Note that projections made by different informed groups vary, but even the most optimistic projections forecast an increase >12% by 2050.)

26 What will be the consequence if the population grows that much? With even the best-case estimate, the consequence is acceleration and intensification of all the problems listed above. Stanford University studies concluded that current human activities are unsustainable. When the study was made several years ago, it concluded that human byproducts and emissions already exceeded the natural regeneration and cleansing capacity of the air and water by 40%. The study estimated the maximum population that would allow for damage reversal and long-term sustainability, and it projected a population growth barrier that would be hard to exceed.

27 What maximum population did the study say would allow for damage reversal and long-term sustainability? Two billion modestly affluent people could live with replenishable fishing and without climate change, massive species extinctions, reef destruction, increased desertification, etc. Any greater number will have a significant impact on the environment. We are experiencing many consequences of overpopulation and overproduction, and even best-case projections predict worsening problems. The actions we take can lessen the damage, but on our present course we will not be able to totally undo that damage in the foreseeable future.

28 What growth barrier did the Stanford study say would be hard to exceed? Our earths environment could probably not long support more than 13 billion people. Death rates would probably keep population growth rates in check beyond that point. We can build more high rises, but high density areas can thrive only where low density areas are available for food production and to offset the human impacts.

29 Which is more responsible for the problems listed above: the expansion of affluence and consumerism or expanding levels of population growth? The problem stems from a world having more people while at the same time more people have greater affluence. The greater the rates of affluence and consumption; the greater the toll on resources and pollution. One man with a private jet, luxury boat and three large homes to heat and cool can consume more fuel than a small village. 80% of the worlds income goes to less than 15% of the people. The gap between the worlds rich and poor widened fivefold between 1870 and Wealthy nations import much of what we consume, but most of the people in poor nations receive no benefit from local resources sold abroad.

30 Should we worry more about expanding affluence or expanding levels of population growth? Since 1800, the population has increased about 700%, but consumption has increased 43,000%, and it continues growing faster than population. Having both more and wealthier people is unsustainable. If we dont want more poverty, the answer is fewer people. Richer people have the greatest impact per capita. The U.S. is a major offender. With 4.6% of the worlds people, the U.S consumes 29% of the worlds resources – a rate 75 times greater than those who live at subsistence level. We cause far more sustainability problems than people living at subsistence level. Yet birthrates are highest in the poorest nations, so they are driving the overpopulation problem. More than 95% of population growth during the next 40 years is predicted to occur in the developing nations. This expansion causes species extinctions and regional environmental damage due to poor sanitation, deforestation, over-farming, etc.

31 How is modern technology causing the problem? More vehicles, buildings, and roads require more resources for operation, construction, heating, etc. And they produce more land, air, and water pollution.

32 How is modern technology causing the problem? Chemical byproducts and discards create biohazards. Advanced fishing technologies lead to overfishing. High tech mining, tree cutting, hauling and manufacturing, speed the rate of over- consumption. Even the orbital sphere around the Earth is now littered with hazardous junk.

33 How can modern technology contribute to solutions? New technologies can reduce pollution when burning fuels (e.g., catalytic converter, better fuel efficiency) Better technologies reduce spoilage. Insect infestation and spoilage result in the loss of up to 20% of all foods during shipment and storage. Recycling technologies can reduce waste. Better medicines and foods keep people more healthy and productive.

34 Didnt the Green Revolution (GR) improve farming output? What were the successes and failures of the GR? In the short term the GR produced dramatic (up to three- fold) increases in food production, but over the long term several problems have occurred: Huge increases in population growth that followed the GR made more people dependent on the continued growth of benefits from GR technologies. Instead, we are now seeing 13% declines in output per hectare from many GR farms due to salting, water shortage, soil damage, and the high cost and overuse of fertilizers, pesticides and other required GR investments.

35 Will genetically-modified foods cause similar production gains? Genetically-modified food technologies have not been well accepted, but they may help to increase yields in some cases. Other new food growing technologies offer some hope of reducing the pressures on fish stocks and getting more food from our declining available arable farmlands. This can help to compensate for losses due to overfishing and land being taken out of cultivation. Food production responds more to income growth than human need. The wealthiest 20% consume about half of the worlds food output. While 800 million people suffer from undernourishment problems, the affluent people discard large quantities of high- quality foods. Growing meat requires far more farmland than just growing vegetables. To feed more people, we might need to devote less land to meat and ethanol production.

36 We seldom hear much about overpopulation. The combined effect of overpopulation and overindulgence of material products is probably the worlds most pressing problem. Yet, except where Republicans and anti-abortion groups complained about support for family planning, the issue was never mentioned by either party in the presidential contest. Many people are concerned about climate change, but climate change is just one of several serious problems caused by overpopulation and overconsumption.

37 Given the urgency of the problem, why does it get such low priority? Perhaps we view overpopulation as a third-world problem, or we feel that there is nothing we can do about it. Economists call for more consumption to stimulate job growth. No one wants to give up an affordable vacation flight to cut pollution. Recent books say that low rates of reproduction should be avoided do to the need for young workers to drive innovation and generate income to support the social safety nets. Many people who distrust the west also distrust the motives of family planning initiatives. We need more airtime and support from the educational establishment to counter these influences and raise the issues priority.

38 Can Catholic nations achieve population control? What Nations have the best and worst records? Spain, Italy, Poland, Russia, Portugal and Japan have the worlds lowest birthrates. Much of Europe has low birthrates, as do Canada, China, and Australia. More than half of these nations are democracies with Catholic majorities. Even some Muslim nations have active family planning programs. The highest birthrates are shown in darkest blue.

39 What Nations have the best and worst records? The U.S has the worlds third largest population, which is projected to reach 422 million by With four new immigrants entering the U.S. per minute, our population is growing mostly due to immigration. Yemen, Palestine, Afghanistan, and most of Africa have the worst records. In those nations the population doubles every decade. Their biggest problems seem to relate to poverty and the lack of family planning education and services. Religious resistance to family planning does exist, but ignorance, indifference by public leaders, and lack of access to family planning probably inhibits family planning more than anything else.

40 What can concerned people do to help reduce the potentially catastrophic problems of overpopulation and overconsumption? Consume less. We now spend 90% of GDP on consumer goods. U.S. homes have doubled in space per occupant, and we buy more cars, electronic devices (e.g. TVs), etc. Spend more on things to reduce fuel consumption and environmental damage. Travel more modestly: According to the NY Times, traveling round-trip from Chicago to Frankfurt generates as much CO 2 per passenger as the average family car produces in a year. Have small families and encourage others to do so. Pick a favorite family planning NGO for contributions. Recommend Life on the Brink, Philip Cafaro and Eileen Crist (Editors), or World on the Edge (free PDF download) or Full Planet, Empty Plates (both by Lester R. Brown) to your book club. Political recommendations will appear on the following pages.

41 On the negative side, six Republican candidates in the 2011 Presidential Primary had 34 children among them (not counting Michele Bachmanns 23 foster children, which I applaud). What does that suggest about their enthusiasm for family planning? Family planning does not appear to be their highest priority. What is the Mexico City Policy? This refers to Ronald Reagans announced withdrawal of support for international agencies that provide any form of support for abortions. This resulted in the U.S. condemning more family planning NGOs than it supported and a substantial reduction of U.S. dollar support for family planning. It remains difficult to get support for any form of international family-planning programs through Congress. What is the political Climate?

42 The U.S government may be hostile to family planning. What about the American people ? On the positive side, many Americans do favor family planning. According to Kenneth Weiss in a March 2, 2013 article in the Los Angeles Times, Nearly two- thirds of American voters believe human population growth is driving other animal species to extinction and that, if the situation gets worse, society has a moral obligation to fix the problem. 50% of those surveyed think the worlds population is currently growing too fast.

43 What we can do politically? Request candidates to talk more about population issues. Ask for schools to discuss it. Ask our candidates to support family planning services both at home and abroad through the U.N. or through NGOs. In place of personal consumerism, support more social spending on things like day care, education, psychological services, rehabilitation, etc. Support carbon, fuel, and excise taxes and use the money to build better systems for high-speed, fuel-efficient mass transit. Support subsidies to green technologies. Get government to stop subsidizing industries we should shrink, such as fishing, logging, livestock grazing (on public lands), fossil fuel production and use, luxury transportation.


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