GSS Logo
Page Heading
• Global Systems Science

POPULATION GROWTH

Home Button
About Button
Student Books
Staying Uptodate Button
Teacher Guides
Software
Order Button

1. What is a Population?

2009 November 4. North American Origins for the Falklands Wolf. By Henry Fountain, The NY Times. Excerpt: The Falklands wolf has puzzled evolutionary biologists since Charles Darwin first encountered it during the voyage of the Beagle in the 1830s. It was the only native land mammal on the Falkland Islands, which are 300 miles off the coast of Argentina. No one knew how it got there or what mainland animals it was descended from — and it did not help that the wolf was hunted to extinction by 1876.
But using genetic analysis, Graham J. Slater, a post-doctoral researcher at the University of California, Los Angeles, and colleagues have solved some of the mystery....
The researchers obtained snippets of DNA from five museum specimens, looked at variations among the samples and compared them with DNA from living species. They were able to build a family tree and a timeline of when the various branches diverged.
Earlier studies of the Falklands wolf had suggested it was related to foxes, but the DNA work showed the closest living relative to be another South American canid, the maned wolf....

2009 July 15. Greater Yellowstone elk suffer worse nutrition and lower birth rates due to wolves. By Tracy Ellig, MSU News. Excerpt: Bozeman -- Wolves have caused elk in the Greater Yellowstone Ecosystem to change their behavior and foraging habits so much so that herds are having fewer calves, mainly due to changes in their nutrition, according to a study published this week by Montana State University researchers.
During winter, nearly all elk in the Greater Yellowstone Ecosystem are losing weight, said Scott Creel, ecology professor at MSU, and lead author on the study....
"Essentially, they are slowly starving," Creel said....
With the presence of wolves, elk browse more - eating woody shrubs or low tree branches in forested areas where they are safer - as opposed to grazing on grass in open meadows where they are more visible, and therefore more vulnerable to wolves.
...the change in foraging habits results in elk taking in 27 percent less food than their counterparts that live without wolves, the study estimates.
...Obviously, wolves kill elk, and direct predation is responsible for much of the decline in elk numbers, but the rate of direct killing is not great enough to account for the elk population declines observed.... In addition to direct predation, the decline is due to low calving rates, which are a subtle but important effect of the wolves' presence, Creel said....

29 March 2005. How Foxes in the Aleutian Henhouse Doomed Islands' Plant Life. By CHARLES PETIT. NY Times. Foxes may not graze, but a new scientific study describes how their arrival on Aleutian islands destroyed rich grasslands and left only sparse tundra. The authors of the report, which appeared in Science last week, say this transformation shows how an entire ecosystem may go into a tailspin if just one new top carnivore shows up. The inadvertent experiment began in the late 1700's and continued into the early 20th century as fur traders looking to expand their supply released nonnative arctic foxes and, in some cases, red foxes on more than 400 Alaskan islands. Some died out, but many populations survived.... The botanical impoverishment that has resulted is the reverse of what usually happens when a new meat-eater comes along. "Traditionally, the predator eats the grazer; the grazer no longer eats the green stuff; and the habitat gets more green," said Dr. Donald Croll, a professor of biology at the University of California, Santa Cruz, and the lead author of the report. An example of the more usual routine is in Yellowstone National Park, where returning wolves, preying on sapling-browsing elk and confining the wary survivors to areas where they can see wolves coming, have touched off a resurgence of willow, aspen and other vegetation. The contrary effect in the Aleutians, once sorted out, has a simple explanation. The grazers on these islands were grass- and seed-eating Aleutian geese, which are smaller cousins of Canada geese. The foxes drove the geese near extinction, which would have been a boon for grasses except that the foxes also feasted on the eggs and hatchlings of puffins, auklets and other ocean-feeding seabirds they found brooding in vast numbers almost everywhere. Some islands lost almost all birds except for cliff-nesting species. And as ground-nesting birds faded, so did their nutrient-rich excrement, or guano, which had been a natural fertilizer. The research team concluded that islands with no foxes received an average 361.9 grams per square meter yearly. Fox-infested islands get just 5.7 grams per square meter of guano per year....

 

Chapters:

  1. What is a Population?
  2. Patterns in Populations
  3. Population Reproduction, Growth, and Change Over Time
  4. The History of Human Population Growth
  5. The Environmental Impact of Populations
  6. One Child
  7. Can We Limit Human Population Growth?
  8. Choosing a World
Addition to Teacher Guide:
The Population Game From NSTA Science Teacher, April 2004.

2. Patterns in Populations

Archive of Past Articles for Chapter 2

1 November 2007. Is the ocean carbon sink sinking? RealClimate website. --David. Excerpt: The past few weeks and years have seen a bushel of papers finding that the natural world, in particular perhaps the ocean, is getting fed up with absorbing our CO2... evidence that the hypothesized carbon cycle positive feedback has begun.
...If changing climate were to cause the natural world to slow down its carbon uptake, or even begin to release carbon, that would exacerbate the climate forcing from fossil fuels: a positive feedback.
The ocean has a tendency to take up more carbon as the CO2 concentration in the air rises, because of Henry's Law, which states that in equilibrium, more in the air means more dissolved in the water. Stratification of the waters in the ocean, due to warming at the surface for example, tends to oppose CO2 invasion, by slowing the rate of replenishing surface waters by deep waters which haven't taken up fossil fuel CO2 yet.
... Le Quere et al. [2007] ... find that the Southern Ocean has begun to release carbon since about 1990....
A decrease in ocean uptake is more clearly documented in the North Atlantic by Schuster and Watson [2007]. They show surface ocean CO2 measurements ... rose by about 15 microatmospheres
...The warming at the end of the last ice age was prompted by changes in Earth's orbit around the sun, but it was greatly amplified by the rising CO2 concentration in the atmosphere. The orbits pushed on ice sheets, which pushed on climate. The climate changes triggered a strong positive carbon cycle feedback which is, yes, still poorly understood.
Now industrial activity is pushing on atmospheric CO2 directly. The question is when and how strongly the carbon cycle will push back.

January 2007. Logarithms and Modelling page has problems in exponential growth as part of the Exercises in Math Readiness [http://math.usask.ca/mrc-cgi bin/emr/first_page.cgi]

January 2007. Exponential growth applet - interactive. See also "logistic growth" http://www.otherwise.com/population/logistic.html

Archive of Past Articles for Chapter 2

 

Chapters:

  1. What is a Population?
  2. Patterns in Populations
  3. Population Reproduction, Growth, and Change Over Time
  4. The History of Human Population Growth
  5. The Environmental Impact of Populations
  6. One Child
  7. Can We Limit Human Population Growth?
  8. Choosing a World

3. Population Reproduction, Growth, and Change Over Time

Archive of Past Articles for Chapter 3

2008 October 7. Future of Giant Turtle Still Uncertain. By Jim Yardly, The New York Times. Excerpt: ...Scientists trying to save one of the world’s most endangered species of freshwater turtles say waiting is their only recourse after a complicated attempt to mate two elderly turtles during this year’s breeding season ended without producing any offspring.
The fate of the Yangtze giant soft-shell turtle seems especially uncertain because only one female is known to exist — an 80-year-old turtle with a leathery shell that lived without notice for a half century inside a zoo in Changsha, the capital of Hunan Province, in southern China. Only when scientists discovered her existence last year did it become clear that a chance remained to save her species.
In May, scientists drove her more than 600 miles to a zoo in the city of Suzhou. There, a male turtle estimated to be 100 years old awaited her. He had been the last known male of the species, though in recent months scientists discovered two more males in Vietnam.
...The female produced roughly 100 eggs and about half appeared to be fertilized. But scientists now say the embryos apparently died in early development....
...Xie Yan, the China program director for the Wildlife Conservation Society, said she remained hopeful.
...“The male and the female didn’t spend enough time together this year,” she said. “This was the first time they mated. Next time will be better.”...

2008 August 7. VIDEO: Lonesome George a Father? National Geographic. The last of his species, the giant tortoise Lonesome George has fertilized 11 eggs with 2 females at his home on one of the Galápagos Islands, scientists say.

2007 November 10. Giant Galapagos Reptiles on Slow Road to Recovery. Bryn Nelson, Science News. Not far from where the Galapagos Islands' most famous loner spends his days, tourists disembark by the inflatable boatload at a modern dock. A ... walkway leads to a natural enclosure sheltering a misanthropic Galapagos tortoise named Lonesome George.
The confirmed bachelor has been a potent icon of conservation ever since he was spotted on remote Pinta Island in 1971 ... Now in his 60s, 70s, or beyond - no one really knows - George may have lived more than half his life in exile. He is quite likely the world's last pure-bred Pinta tortoise ...
Last April, however, the surprise discovery that Lonesome George has a genetic cousin on another island cast doubt, in a hopeful way, on George's one-of-a-kind status. The revelation is just one illustration of how genetics and conservation biology are intermingling to rewrite an oversize reptile's evolutionary past and to reshape plans to safeguard the remaining tortoise species well into the future.

2007 May 8. A Lonesome Tortoise, and a Search for a Mate. By JOHN TIERNEY, NY Times. Excerpt: When I met Lonesome George two decades ago, in his pen on the main island of the Gal‡pagos, I had the usual impulse to fix up the world's most famous bachelor.... I didn't find her, of course, so I went back to George's pen to bid a sad farewell to him and his species. Then I penned a long - and quite moving, I thought - contemplation of the ethics of conservation, the destructiveness of man and the meaning of life. Now it seems the obituary was premature. ... Last week, after sampling the genes of a few tortoises on Isabela Island, biologists announced that there is probably at least one Pinta tortoise somewhere among the thousands of tortoises there. Next year the researchers hope to find a female to take back to George's pen.
...George is not what you would call a stud. When I visited him in 1985, he was thought to be a relatively young adult, maybe 50 years old, but he was already a confirmed bachelor. He hadn't shown any interest in two females of a similar species placed in his pen. One had flipped over and drowned in the wading pool. The keepers weren't positive that George had driven this tortoise to her death, but he definitely hadn't been doing any Barry White serenades.
A few years later, in 1993, there was briefly a companion known as "Lonesome George's girlfriend," but she was not a tortoise. She was a 26-year-old graduate student in zoology from Switzerland named Sveva Grigioni. By coating her hands in the genital secretions of female tortoises and gently stroking him, she managed to demonstrate a couple of times (in the course of several months' work) that George was capable of an erection. But whereas her touch could induce other male tortoises to reach orgasm within a few minutes, with George she never managed to collect any sperm. ..."He started to try copulation," Ms. Grigioni said, "but it was like he didn't really know how to." To be fair to George, he's never been observed with a female of his race, Geochelone nigra abingdoni....The tortoise populations in the Gal‡pagos were devastated first by hungry whalers and pirates, and then by museum collectors who were far more energetic than the sailors in scouring the islands for the few remaining animals. Until George was discovered, the last tortoises seen alive on Pinta were the ones captured and killed a century ago by an expedition from the California Academy of Science....

Archive of Past Articles for Chapter 3

 

 

Chapters:

  1. What is a Population?
  2. Patterns in Populations
  3. Population Reproduction, Growth, and Change Over Time
  4. The History of Human Population Growth
  5. The Environmental Impact of Populations
  6. One Child
  7. Can We Limit Human Population Growth?
  8. Choosing a World

4. The History of Human Population Growth

2010 January 18. Genome Study Provides a Census of Early Humans. By Nicholas Wade, The NY Times. Excerpt: From the composition of just two human genomes, geneticists have computed the size of the human population 1.2 million years ago from which everyone in the world is descended.
They put the number at 18,500 people, but this refers only to breeding individuals, the “effective” population. The actual population would have been about three times as large, or 55,500.
...In biological terms, it seems, humans were not a very successful species, and the strategy of investing in larger brains than those of their fellow apes had not yet produced any big payoff. Human population numbers did not reach high levels until after the advent of agriculture.
Geneticists have long known that the ancestors of modern humans numbered as few as 10,000 at some time in the last 100,000 years. The critically low number suggested that some catastrophe, like disease or climate change induced by a volcano, had brought humans close to the brink of extinction.
If the new estimate is correct, however, human population size has been small and fairly constant throughout most of the last million years, ruling out the need to look for a catastrophe....

2004 September. India's Population to Surpass China's By 2035. The 2004 World Population Data Sheet, released this month by the Population Reference Bureau, http://www.prb.org/, projects an overall global population increase of 45% to 9.3 billion people by the year 2050. The United States is expected to remain the third most populous country through that year, falling behind India, which will become the most populous country, and China, which will drop to number two. PRB predicts that most of the population growth will occur in the developing countries, despite higher HIV/AIDS infection rates and higher infant mortality rates than in the developed world. The figures assume that HIV/AIDS prevalence in Africa will peak in 10-15 years and then rates will drop on the continent, where they are already decreasing in 14 of 38 countries. The gap between the developed and developing countries' figures is also attributed to aging populations, along with more frequent contraceptive use and lower birth rates in several European countries.

Population Density Maps -- http://sedac.ciesin.columbia.edu/plue/gpw

 

Chapters:

  1. What is a Population?
  2. Patterns in Populations
  3. Population Reproduction, Growth, and Change Over Time
  4. The History of Human Population Growth
  5. The Environmental Impact of Populations
  6. One Child
  7. Can We Limit Human Population Growth?
  8. Choosing a World

5. The Environmental Impact of Populations

Archive of Past Articles for Chapter 5

2009 November 19. The New Republic: Combating Climate For The Ladies. By Lydia Depillis, NPR. Excerpt: Is climate change gender-neutral? Not according to the U.N. Population Fund, which earlier today released a report arguing that women suffer disproportionately from the impacts of global warming....
But on the flipside, the report argues, women are also in the best position to help mitigate both the causes and effects of rising temperatures — which is why policies to empower women, like targeted microloans and reproductive healthcare, shouldn't be treated as separate from climate policy.
...Letting women control their own reproductive destines is essential not only for their own well-being, but also to head off future emissions. Population growth, the UNFPA notes, has been responsible for between 40 percent to 60 percent of past emissions growth — and getting people to change their consumption habits has proven harder than simply helping women to make their own decisions on how many kids to have, through better education or access to birth control....
Beyond that, though, women are crucial to environmental management for things they can do, rather than things they can chose not to do. For example, women produce 60 percent to 80 percent of the food in developing countries, and often know agricultural techniques that sequester carbon and also keep fields in better shape....

2009 July 31. The Food, Energy and Environment ‘Trilemma’. By John Lorinc, The NY Times. Excerpt: At the 2009 Bio World Congress on Industrial Biotechnology, held in Montreal last week, industry players and scientists found themselves pondering two seemingly contradictory concerns.
One focused on how rapid advances in genetic engineering and biotechnology can expand the market for cellulosic ethanol and other “second-generation biofuels,” which are touted as low-emission substitutes for corn ethanol (itself a partial substitute for gasoline).
The other involved the problem of ensuring that exponential growth in the global biofuel market — which is projected to grow 12.3 percent a year through 2017, according to one recent study of the industry — will not hurt the environment and divert vast tracks of arable land needed for food or grain production.
A paper published in Science earlier this month, referred to the triple challenges of energy, environment and food as the biofuel “trilemma.” The authors identified five “beneficial” sources of biomass: perennial plants grown on abandoned farm fields, crop residue, sustainably harvested wood residue, double or mixed crops, and industrial/municipal waste.
“In a world seeking solutions to its energy, environmental, and food challenges, society cannot afford to miss out on the global greenhouse-gas emission reductions and the local environmental and societal benefits when biofuels are done right,” the authors state. “However, society also cannot accept the undesirable impacts of biofuels done wrong.”...

2009 July 31. Family Planning Has Major Environmental Impact. ScienceDaily. Excerpt: Some people who are serious about wanting to reduce their "carbon footprint" on the Earth have one choice available to them that may yield a large long-term benefit – have one less child.
A study by statisticians at Oregon State University concluded that in the United States, the carbon legacy and greenhouse gas impact of an extra child is almost 20 times more important than some of the other environmentally sensitive practices people might employ their entire lives – things like driving a high mileage car, recycling, or using energy-efficient appliances and light bulbs.
The research also makes it clear that potential carbon impacts vary dramatically across countries. The average long-term carbon impact of a child born in the U.S. – along with all of its descendants – is more than 160 times the impact of a child born in Bangladesh.
"In discussions about climate change, we tend to focus on the carbon emissions of an individual over his or her lifetime," said Paul Murtaugh, an OSU professor of statistics. "Those are important issues and it's essential that they should be considered. But an added challenge facing us is continuing population growth and increasing global consumption of resources."
In this debate, very little attention has been given to the overwhelming importance of reproductive choice, Murtaugh said. When an individual produces a child – and that child potentially produces more descendants in the future – the effect on the environment can be many times the impact produced by a person during their lifetime.
Under current conditions in the U.S., for instance, each child ultimately adds about 9,441 metric tons of carbon dioxide to the carbon legacy of an average parent – about 5.7 times the lifetime emissions for which, on average, a person is responsible....

2008 Nov. The Food and Farming Transition. by Richard Heinberg, MuseLetter #199. Excerpt: The only way to avert a food crisis resulting from oil and natural gas price hikes and supply disruptions while also reversing agriculture’s contribution to climate change is to proactively and methodically remove fossil fuels from the food system.
The removal of fossil fuels from the food system is inevitable: maintenance of the current system is simply not an option over the long term....
Given the degree to which the modern food system has become dependent on fossil fuels, many proposals for de-linking food and fuels are likely to appear radical. However, efforts toward this end must be judged not by the degree to which they preserve the status quo, but by their likely ability to solve the fundamental challenge that will face us: the need to feed a global population of 7 billion with a diminishing supply of fuels available to fertilize, plow, and irrigate fields and to harvest and transport crops.
If this transition is undertaken proactively and intelligently, there could be many side benefits—more careers in farming, more protection for the environment, less soil erosion, a revitalization of rural culture, and more healthful food for everyone....

2008 July 21. Mideast Facing Choice Between Crops and Water. By Andrew Martin, The New York Times. Excerpt: CAIRO — Global food shortages have placed the Middle East and North Africa in a quandary, as they are forced to choose between growing more crops to feed an expanding population or preserving their already scant supply of water.
For decades nations in this region have drained aquifers, sucked the salt from seawater and diverted the mighty Nile to make the deserts bloom. But those projects were so costly and used so much water that it remained far more practical to import food than to produce it. Today, some countries import 90 percent or more of their staples.
Now, the worldwide food crisis is making many countries in this politically volatile region rethink that math.
....The population of the region has more than quadrupled since 1950, to 364 million, and is expected to reach nearly 600 million by 2050. By that time, the amount of fresh water available for each person, already scarce, will be cut in half, and declining resources could inflame political tensions further.
“The countries of the region are caught between the hammer of rising food prices and the anvil of steadily declining water availability per capita,” Alan R. Richards, a professor of economics and environmental studies at the University of California, Santa Cruz, said via e-mail. “There is no simple solution.”...

2008 June 14. China Increases Lead as Biggest Carbon Dioxide Emitter. By Elisabeth Rosentha, The New York Times. Excerpt: China has clearly overtaken the United States as the world's leading emitter of carbon dioxide, the main heat-trapping gas, a new study has found, its emissions increasing 8 percent in 2007. The Chinese increase accounted for two-thirds of the growth in the year's global greenhouse gas emissions, the study found.
The report, released Friday by the Netherlands Environmental Assessment Agency, found that in 2007 China's emissions were 14 percent higher than those of the United States. In the previous year's annual study, the researchers found for the first time that China had become the world's leading emitter, with carbon emissions 7 percent higher by volume than the United States in 2006.
"The difference had grown to a 14 percent difference, and that's indeed quite large," said Jos Olivier, a senior scientist at the Dutch agency. "It's now so large that it's quite a robust conclusion."
China's emissions are most likely to continue growing substantially for years to come because they are tied to the country's strong economic growth and its particular mix of industry and power sources, the researchers said.
China is heavily dependent on coal and has seen its most rapid growth in some of the world's most heavily polluting industrial sectors: cement, aluminum and plate glass.
The United States still has a vast lead in carbon dioxide emissions per person. The average American is responsible for 19.4 tons. Average emissions per person in Russia are 11.8 tons; in the European Union, 8.6 tons; China, 5.1 tons; and India, 1.8 tons.
Experts said the new data underscored the importance of getting China to sign on to any new global climate agreement. Neither China nor the United States participated in the current treaty to limit emissions, the Kyoto Protocol, which expires in 2012 and will be replaced by a new agreement to be signed in Copenhagen at the end of 2009.
...

24 November 2007. Far From Beijing's Reach, Officials Bend Energy Rules. The New York Times--By HOWARD W. FRENCH. Excerpt: QINGTONGXIA, China - When the central government in Beijing announced an ambitious nationwide campaign to reduce energy consumption two years ago, officials in this western regional capital got right to work: not to comply, but to engineer creative schemes to evade the requirements.
The energy campaign required local officials to raise electricity prices as a way of discouraging the growth of large energy-consuming industries and forcing the least efficient of these users out of business. Instead, fearing the impact on the local economy, the regional government brokered a special deal for the Qingtongxia Aluminum Group, which accounts for 20 percent of this region's industrial consumption and roughly 10 percent of its gross domestic product.
Local officials arranged for the company to be removed from the national electrical grid and supplied directly by the local company, exempting it from expensive fees,
...national officials aimed to cut energy use by 20 percent per dollar of output within five years. China's energy consumption has more than quadrupled since 1980. The environmental toll is staggering. The country is already the world's largest user of coal, the dirtiest type of energy. China's coal consumption alone is projected to double in the next 20 years, according to the International Energy Agency.
...Even before the national energy consumption campaign began in 2005, Ningxia officials worked to get around environmental regulations that could hinder growth. Although Beijing issued rules in 2002 trying to limit the number of new coal-burning power plants, Ningxia has built at least three that either did not have the required permission, or failed to meet new environmental standards, according to the State Environmental Protection Administration.
... "To get reforms implemented, two things have to be done," said Lin Boqiang, director of the China Energy Research Institute at Xiamen University. "One is to rate the local government's performance on compliance, and if they don't comply telling people they have to go. The other is introducing financially meaningful penalties. We haven't seen either of these yet."

26 September 2007. Can Earth's Plants Keep up with Us? by Stephanie Renfrow. Excerpt: ...as global population and incomes rise, will plants be able to keep up with the human appetite? And if they cannot, which regions will be short on food and other plant-based resources, and what will that mean for nations as they try to assure food security for their citizens?
Marc Imhoff, a biophysical scientist with NASA, has been exploring these questions with colleagues from the University of Maryland's Earth System Science Interdisciplinary Center, the World Wildlife Fund, and the International Food Policy Research Institute for six years. He said, "Our primary motivation has been to find out where we stand relative to our survival on the planet, and what our needs are compared to the capability of the biosphere to sustain them.
...To measure net primary production, Imhoff used an index, or scale, of vegetation based on satellite data from the Advanced Very High Resolution Radiometer (AVHRR) instrument. ...He combined the monthly vegetation data with temperature, humidity, rainfall, and land cover type in a model that simulates plant growth. The model provided Imhoff and his colleagues an estimate of the planet's net primary production....
...Imhoff's next step was to measure the amount of net primary production that humans use worldwide in an average year, and then tie it to cultural consumption habits. To do that, he turned to statistics from the United Nations Food and Agricultural Organization (FAO) on food and fiber consumption by country, taking the data from 1995 as a typical year that matched the satellite timeline....
...To Imhoff, a ... surprising finding was the importance of technology in helping balance the equation between supply and consumption. "We found that using improved technology-especially in harvesting and storage techniques-can actually halve the amount of waste in agricultural production," he said. "Take logging. Without the benefits of improved harvesting technology, you might literally lose a tree for every one that you use."
...Asia's per-capita consumption is on the rise," he said. "If consumption begins to match Western levels, there will be a significant increase in demand for food and fiber products. If technology improvements do not come with that growth, then you'll see populations that are outstripping their regional food production capacity. ...Although citizens in industrialized countries may not find the rising population in developing nations of immediate concern, poverty has been connected to terrorism, war, underemployment, border pressures, disease, and political unrest....

10 April 2007. Millions Face Hunger From Climate Change. By THE ASSOCIATED PRESS Excerpt: MEXICO CITY (AP) -- Rising global temperatures could melt Latin America's glaciers within 15 years, cause food shortages affecting 130 million people across Asia by 2050 and wipe out Africa's wheat crop, according to a U.N. report released Tuesday. The report, written and reviewed by hundreds of scientists, outlined dramatic effects of climate change including rising sea levels, the disappearance of species and intensifying natural disasters. It said 30 percent of the world's coastlines could be lost by 2080. ...Polar ice caps will likely melt, opening a waterway at the North Pole and threatening to make the Panama Canal obsolete, IPCC member Edmundo de Alba said. Warmer waters will spawn bigger and more dangerous hurricanes that will threaten coastlines not traditionally affected by them. Latin America's diverse ecosystems will struggle with intense droughts and flooding and as many as 70 million people in the region will be left without enough water, according to the report. ''What's clear is places suffering from drought are going to become drier, and places with a large amount of precipitation are going to see an increase in precipitation,'' de Alba said. Many Latin American farmers will have to abandon traditional crops such as corn, rice, wheat and sugar as their soil becomes increasingly saline, and ranchers will have to find new ways to feed their livestock, scientists said. ...In Asia, nearly 100 million people will face the risk of floods from seas that are expected to rise between 0.04 inches to 0.12 inches annually, slightly higher than the global average. The report suggests that a 3.6-degree increase in mean air temperature could decrease rain-fed rice yields by 5 percent to 12 percent in China. In Bangladesh, rice production may fall by just under 10 percent and wheat by a third by the year 2050. The drops in yields combined with rising populations could put close to 50 million extra people at risk of hunger by 2020, 132 million by 2050 and 266 million by 2080, the report said. ...On the Net: http://www.ipcc.ch/

7 February 2007. China Says Rich Countries Should Take Lead on Global Warming. By JIM YARDLEY, NY Times. Excerpt: BEIJING, Feb. 6 - China said Tuesday that wealthier countries must take the lead in curbing greenhouse gas emissions and refused to say whether it would agree to any mandatory emissions limits that might hamper its booming economy. Jiang Yu, a spokeswoman for the Foreign Ministry, said ... "It must be pointed out that climate change has been caused by the long-term historic emissions of developed countries and their high per capita emissions," she said, adding that developed countries have responsibilities for global warming "that cannot be shirked." ...China is the world's second largest emitter of the greenhouse gases contributing to climate change, .... Last November, the International Energy Agency in Paris predicted that China would pass the United States in emissions of carbon dioxide in 2009. ...Qin Dahe, chief of the China Meteorological Administration, told reporters ... "President Hu Jintao has said that climate change is not just an environmental issue but also ... ultimately a development issue." ..."As a developing country that's growing rapidly and has a big population, to thoroughly transform the energy structure and use clean energy would need a lot of money," Mr. Qin said, according to Reuters...

The Gazette
http://www.populationconnection.org/education/gazette/
Population Activities http://www.populationconnection.org
Population Reference Bureau http://www.prb.org/
United Nations Population fund http://www.unfpa.org/

Archive of Past Articles for Chapter 5

 

Chapters:

  1. What is a Population?
  2. Patterns in Populations
  3. Population Reproduction, Growth, and Change Over Time
  4. The History of Human Population Growth
  5. The Environmental Impact of Populations
  6. One Child
  7. Can We Limit Human Population Growth?
  8. Choosing a World

6. One Child

Archive of Past Articles for Chapter 6

2009 Dec 15, In 2025, India to Pass China in Population, U.S. Estimates. By SAM ROBERTS, NY Times. Excerpt: India will become the world's most populous country in 2025, surpassing China, where the population will peak one year later because of declining fertility, according to United States Census Bureau projections released Tuesday.
The bureau suggests that the projected peak in China, 1.4 billion people, will be lower than previously estimated and that it will occur sooner. With the fertility rate declining to fewer than 1.6 births per woman in this decade from 2.2 in 1990, China's overall population growth rate has slowed to 0.5 percent annually.
... China and India alone account for 37 percent of the world's population of about 6.8 billion. Every minute, the bureau's estimates, 250 people are born worldwide and 107 die, for an increase of more than 75 million annually....
... After China and India, the most populous countries are, in order, the United States, Indonesia, Brazil, Pakistan, Bangladesh, Nigeria, Russia and Japan....

2009 May 28. India, Enlightened. By George Black, NRDC OnEarth. Raise a Billion People out of Poverty Without Destroying the Environment. Can It Be Done?

2008 Summer. Global Appetites: How Better Nutrition, Sustainable Fuel Accelerated the Food Emergency. Dr. Mark Rosegrant, The Interdependent, Vol. 6 No. 2. pages 12-13. Excerpt: Some of today's global food woes are the unintended consequences of success, according to Dr. Mark Rosegrant of the International Food Policy Research Institute. He looks at warnings over the past decade, how new prosperity brought better nutrition for millions and how the quest for alternative fuels to protect the planet actually set the stage for trouble. "Biofuels Blamed in Food Cost"...

2008 July. Coal in China. by Richard Heinberg, MuseLetter 195. Excerpt: China is the world's foremost coal producer and consumer, surpassing the United States by a factor of two on both scores and accounting for 40 percent of total world production. Moreover, its coal consumption has been rising rapidly, at a rate of up to ten percent per year (which translates to a doubling of demand every 7 years). While China is a significant producer of oil and natural gas, coal dominates the nation's fossil-fuel reserve base. About 70 percent of China's total energy is derived from coal, and about 80 percent of its electricity. The country has recently become the world's foremost greenhouse gas emitter due to its growing, coal-fed energy appetite. ... The nation's short-term survival strategy thus centers on producing enormous quantities of coal today, and far more in the future.
However, there are signs that China's domestic coal production growth may not be able to keep up with rising demand for much longer.
... The supply problems discussed here appear already to be manifesting. During the winter of 2007-2008, power plants in many parts of the country ran short of coal due to soaring prices and transport bottlenecks, while snow and ice storms disrupted power transmission. A People's Daily article, quoting Zhang Guobao, deputy head of the National Development and Reform Commission, noted that only a "fragile balance" existed in the thermal coal market despite huge and growing coal output. During that same winter, prices for internationally traded coal climbed substantially.
... China's furious pace of economic growth, which is often touted as a sign of success, may turn out to be a fatal liability. Simply put, the nation appears to have no Plan B. No fossil fuel other than coal will be able to provide sufficient energy to sustain current economic growth rates in the years ahead, and non-fossil sources will require unprecedented and perhaps unachievable levels of investment just to make up for declines in coal production-never mind providing enough to fuel continued annual energy growth of seven to ten percent per year....

26 August 2007. As China Roars, Pollution Reaches Deadly Extremes. The New York Times. By JOSEPH KAHN and JIM YARDLEY. Excerpt: BEIJING, Aug. 25 - No country in history has emerged as a major industrial power without creating a legacy of environmental damage that can take decades and big dollops of public wealth to undo. China's cement factories... use 45 percent more power than the world average, and its steel makers use about 20 percent more. But just as the speed and scale of China's rise as an economic power have no clear parallel in history, so its pollution problem has shattered all precedents. Environmental degradation is now so severe, with such stark domestic and international repercussions, that pollution poses not only a major long-term burden on the Chinese public but also an acute political challenge to the ruling Communist Party. ...Pollution has made cancer China's leading cause of death, the Ministry of Health says. Ambient air pollution alone is blamed for hundreds of thousands of deaths each year. Nearly 500 million people lack access to safe drinking water.
...For air quality, a major culprit is coal, on which China relies for about two-thirds of its energy needs. It has abundant supplies of coal and already burns more of it than the United States, Europe and Japan combined. But even many of its newest coal-fired power plants and industrial furnaces operate inefficiently and use pollution controls considered inadequate in the West.
...Emissions of sulfur dioxide from coal and fuel oil, which can cause respiratory and cardiovascular diseases as well as acid rain, are increasing even faster than China's economic growth.... Other major air pollutants, including ozone, an important component of smog, and smaller particulate matter, called PM 2.5, emitted when gasoline is burned, are not widely monitored in China.
...Perhaps an even more acute challenge is water. China has only one-fifth as much water per capita as the United States. But while southern China is relatively wet, the north, home to about half of China's population, is an immense, parched region that now threatens to become the world's biggest desert. ...In many parts of China, factories and farms dump waste into surface water with few repercussions. China's environmental monitors say that one-third of all river water, and vast sections of China's great lakes, the Tai, Chao and Dianchi, have water rated Grade V, the most degraded level, rendering it unfit for industrial or agricultural use.
...Officials have rejected proposals to introduce surcharges on electricity and coal to reflect the true cost to the environment. The state still controls the price of fuel oil, including gasoline, subsidizing the cost of driving.

6 April 2007. To Fortify China, Soybean Harvest Grows in Brazil. By ALEXEI BARRIONUEVO, NY Times. Excerpt: RONDONîPOLIS, Brazil - For more than 2,000 years, the Chinese have turned soybeans into tofu, a staple of the country's diet. But as its economy grows, so does China's appetite for pork, poultry and beef, which require higher volumes of soybeans as animal feed. Plagued by scarce water supplies, China is turning to a new trading partner 15,000 miles away - Brazil - to supply more protein-packed beans essential to a richer diet. China's global scramble for natural resources is leading to a transformation of agricultural trading around the world. In China, vanishing cropland and diminishing water supplies are hampering the country's ability to feed itself, and the increasing use of farmland in the United States to produce biofuels is pushing China to seek more of its staples from South America, where land is still cheap and plentiful. ...The Chinese want to connect directly with Brazilian farmers, bypassing the multinational grain merchants. While they have yet to make a major purchase of cropland in Brazil, they are looking to invest in improved facilities and upgrade the antiquated rail system.
China began looking overseas for more soybean supplies in the mid-1990s, when the scope of its land and water problems became clearer. Beijing has also chosen to use more of its arable farmland to grow fruits and vegetables, crops that make better use of China's cheap labor and scarcer water supplies to generate higher returns on the export market....

Archive of Past Articles for Chapter 6

Chapters:

  1. What is a Population?
  2. Patterns in Populations
  3. Population Reproduction, Growth, and Change Over Time
  4. The History of Human Population Growth
  5. The Environmental Impact of Populations
  6. One Child
  7. Can We Limit Human Population Growth?
  8. Choosing a World

 

7. Can We Limit Human Population Growth?

Archive of Past Articles for Chapter 7

2009 November 14. Broaching Birth Control With Afghan Mullahs. By Sabrina Tavernise, The NY Times. Excerpt: MAZAR-I-SHARIF, Afghanistan — The mullahs stared silently at the screen. They shifted in their chairs and fiddled with pencils. Koranic verses flashed above them, but the topic was something that made everybody a little uncomfortable.
...It was a seminar on birth control, a likely subject for a nation whose fertility rate of 6 children per woman is the highest in Asia. But the audience was unusual: 10 Islamic religious leaders from this city and its suburbs, wearing turbans and sipping tea.
...Nothing in Islam expressly forbids birth control. But it does emphasize procreation, and mullahs, like leaders of other faiths, consider children to be blessings from God, and are usually the most determined opponents of having fewer of them.
It is an attitude that Afghanistan can no longer afford, in the view of the employees of the nonprofit group that runs the seminars, Marie Stopes International. The high birthrate places a heavy weight on a society where average per capita earnings are about $700 a year. It is also a risk to mothers. Afghanistan is second only to Sierra Leone in maternal mortality rates, which run as high as 8 percent in some areas....

2008 March. Family Planning and Access to Safe and Legal Abortion are Vital to Safeguard the Environment. By Joseph Speidel, M.D. and Richard Grossman, M.D. Contraception, Volume 76 Issue 6 - December 2007 - pages 415-417 Speidel, et al, Reprinted in The Reporter (Population Connection). Excerpt: ...One valid way of quantifying our use of resources is by calculating our ecological footprint* (EF). This concept is based on the understanding that all human activities require space-to live on, to grow food on, for developing resources, and for disposal of waste....
...Using these calculations, we find that people are using an average of 2.2 hectares (5.5 acres) of the planet's resources per person, a full 0.5 hectares (1.1 acres) more than our fair share.... The worldwide overshoot of 30% helps to explain environmental deterioration.
...Because our children and grandchildren will suffer, limiting human numbers and consumption have become moral issues, if not issues of life or death. Fortunately, many couples want to limit their childbearing far below their current fertility. What is missing is access to good family planning....
...Of 210 million pregnancies annually worldwide, 80 million (38%) are unplanned, and 46 million (22%) end in abortion.
More than 200 million women in developing countries would like to delay their next pregnancy-or stop bearing children altogether-but rely on traditional, less effective methods of contraception (64 million) or use no method because they lack access or face other barriers to using contraception (137 million). These barriers include cultural values that support high fertility, opposition to use of contraception by family members, and fears about health risks or side effects of contraception.
...the United States-the world's third largest country-is experiencing rapid population growth of nearly three million each year. The United States is projected to grow from 303 million in 2007 to nearly 350 million in 2025 and to 420 million by 2050. An estimated 1.4 million of 4.1 million annual U.S. births result from unintended pregnancy.... Even with immigration contributing more than one million people annually, unintended pregnancy is the source of about half of annual population growth in the United States...

2008 Summer. More Hunger, Less Hope: Striving to Grasp. Barbara Crossette, The Interdependent, Vol. 6 No. 2. pages 10-11. Excerpt: It is not as if there were no warnings over the last decade about the limitations of food production in an era of dwindling investment and innovation in agriculture and rapid population growth, with millions more people also able to eat better. But few agronomists or economists could have predicted that the law of supply and demand would kick in as harshly as it did this year. It was the combustible mix of general global economic jitters, big increases in consumer demand, record energy prices and the campaign to reduce oil dependence and carbon emissions by turning food crops into fuel that combined to send food prices skyrocketing. The World Food Program's director, Josette Sheeran, an American, calls it a "perfect storm." That was before two catastrophic natural disasters in Asia: a cyclone in Burma's rice-growing area and the earthquake in China. In affected areas of Burma, next year's rice harvest may also have been lost as seeds were washed away...

11 May 2006. Scientists Will Gather to Discuss Safety of Abortion Pill. By GARDINER HARRIS NY Times. Worried about a bacterial infection that led to the deaths of at least five women who took the abortion pill RU-486, scientists from the nation's leading public health agencies will gather in Atlanta today for the first meeting in 10 years on the drug's safety. ...Abortion experts have been at a loss to explain why four of the deaths occurred in California. Initially, the F.D.A. investigated whether the pills used in California might have been contaminated, but an agency official said tests had found no evidence of contamination. Another theory concerned the role a dry climate might play in encouraging the growth of Clostridium sordellii, which lives in soil. Some experts believe that pregnant women who take RU-486 with another drug, misoprostol, are more vulnerable to infection. RU-486 by itself ends early pregnancies, but the pill is routinely given along with misoprostol, which causes uterine contractions ...There has been no hint that the F.D.A. is considering further restrictions on the use of the drug. ...A 43-year-old New York mother of two who said that she had had "every kind of abortion," told her abortion provider during a counseling session recently that she would consider only a pill-based procedure. "I do not like doctors and hospitals," said the woman, who did not wish her name to be used for privacy reasons. "Both of my children were born at home without anything. And that's how I want to have my abortion: in home, in my privacy, at my own pace and without somebody's other agenda over me." ...Anne Hawkins, 36, also of New York, said she, too, had had both pill-based and surgical abortions. But taking RU-486, she said, "was the worst experience, the most physically and emotionally painful thing, that I've ever been through." Ms. Hawkins had another abortion in March, and she chose surgery. "It was 10 minutes, max, and then it was over," Ms. Hawkins said of the surgical procedure. "The pill for me was the experience of having a baby. Contractions for 10 hours, sweating, screaming, being by myself. It was emotionally scarring and physically horrible."

Archive of Past Articles for Chapter 7

Chapters:

  1. What is a Population?
  2. Patterns in Populations
  3. Population Reproduction, Growth, and Change Over Time
  4. The History of Human Population Growth
  5. The Environmental Impact of Populations
  6. One Child
  7. Can We Limit Human Population Growth?
  8. Choosing a World

 

8. Choosing a World

2008 Summer. Making Megacities Livable. The Interdependent, Vol. 6 No. 2. pp. 31-32. Excerpt: In 1900 150 million people lived in cities. By 2000, it was 2.8 billion people, a 19-fold increase. As of 2008, more than half of us are living in cities - making us, for the first time, an urban species. In 1900 there were only a handful of cities with a million people. Today 414 cities have at least that many inhabitants. And there are 20 megacities with 10 million or more residents. Tokyo, with 35 million residents, has more people than all of Canada. Mexico City's population of 19 million is nearly equal to that of Australia. New York, São Paulo, Mumbai (formerly Bombay), Delhi, Shanghai, Kolkata (Calcutta) and Jakarta follow close behind. Rethinking How We Get Around [We] are seeing the emergence of a new urbanism, a planning philosophy that environmentalist Francesca Lyman says "seeks to revive the traditional city planning of an era when cities were designed around human beings instead of automobiles." One of the most remarkable modern urban transformations has occurred in Bogotá, Colombia, where Enrique Peñalosa served as mayor for three years. Under his leadership, the city banned the parking of cars on sidewalks, created or renovated 1,200 parks, introduced a highly successful bus-based rapid transit system, built hundreds of kilometers of bicycle paths and pedestrian streets, reduced rush-hour traffic by 40 percent, planted 100,000 trees and involved local citizens directly in the improvement of their neighborhoods. In doing this, he created a sense of civic pride among the city's eight million residents, making the streets of Bogotá in this strife-torn country safer than in Washington, DC.

2008 April 11. Can People Have Meat and a Planet, Too? By ANDREW C. REVKIN. NY Times. Excerpt: The world has seen the first international conference on manufacturing meat. This is the process, tested so far only at laboratory scale, of growing pork, chicken, or beef through cell culture in vats instead of raising and slaughtering animals.
…The three-day meeting of the In Vitro Meat Consortium, held at the Norwegian Food Research Institute, is wrapping up today. It brought together biologists, engineers, government officials and entrepreneurs seeking - for both environmental and ethical reasons - to move from animal husbandry to technology as a means of providing the kind of protein people crave in a world heading toward 9 billion ever more affluent mouths.
A paper presented at the meeting concluded that, for the moment, the costs of cultured meat can't come close yet to competing with, say, unsubsidized chicken. (A pdf is downloadable here.) The paper noted the reality of the climb up the protein ladder as countries move out of poverty, with global meat consumption at about 270 million metric tons in 2007 and growing at about 4.7 million tons per year.
It laid out the theory: "The environmental impact of meeting this forecast demand from existing livestock systems is significant. Cultured meat technology offers an alternative production route for a proportion of this consumption. This would then allow a downsized livestock production system to continue to be ecologically sound and to meet basic animal welfare needs."
The group noted that costs for research, large-scale testing, and public relations will be significant, and anticipated that governments and nonprofit groups would chip in. That seems idealistic, at best, in a world with deeply entrenched interests linking ranching, the agrochemical industry, and giant restaurant chains.
…For the moment, startup costs aside, the conferees concluded that unsubsidized chicken-raising still comes in at half the price. But the century is yet young…

Population Activities http://www.populationconnection.org

Population Reference Bureau http://www.prb.org/

United Nations Population fund http://www.unfpa.org/

 

Chapters:

  1. What is a Population?
  2. Patterns in Populations
  3. Population Reproduction, Growth, and Change Over Time
  4. The History of Human Population Growth
  5. The Environmental Impact of Populations
  6. One Child
  7. Can We Limit Human Population Growth?
  8. Choosing a World

Please take our web survey!

GSS Home | About | Student Books | Staying Up to Date | Teacher Guides | Software | Order

Lawrence Hall of Science    © Monday, 22-Mar-2010 06:25:56 PDT The Regents of the University of California    Contact GSS    Updated Tuesday, 09-Feb-2010 12:13:35 PST