Slowing urban sprawl, adding forests curb floods and help rivers

By Brian Wallheimer
August 18, 2010

WEST LAFAYETTE, Ind. - Controlling urban growth and increasing forested land are the most effective ways to decrease future water runoff and flooding, according to a Purdue University study.

Bryan Pijanowski, an associate professor of forestry and natural resources, used a model to simulate Michigan's Muskegon River watershed runoff rates from 1900 through the present and forecast them 30 years into the future. Several scenarios, including forest regrowth, urbanization, and buffers between development and streams, were analyzed to estimate their impact on rivers and streams.

"Changes in the land's surface feed back to runoff. Urban sprawl and impervious surfaces are the biggest culprits," Pijanowski said. "If you're able to control development, it is the most effective way to save our river ecosystem."

Pijanowski said urban areas in the United States would double in 20 years at the current rate. In the model predictions, doubling the urban area in the Muskegon River watershed would increase runoff by 1 1/2 times.

Excess runoff can have several consequences, including flooding, increases in agricultural nutrients and urban pollutants entering nearby water and affecting aquatic life, increases in water temperature in rivers and streams that can affect aquatic life, and changes in the apportionment of water to wetlands and groundwater.

Pijanowski's findings, published in the early online version of the journal Environmental Management, suggest that slowing the rate of urban sprawl would be the most effective way to reduce or control runoff. Adding forest near rivers and streams and requiring buffer zones between those waterways and development also could help. …

Slowing urban sprawl, adding forests curb floods and help rivers

Technorati Tags: population,urban sprawl,forest,environmental restoration

How women can save the planet

“And the one proven way to reduce fertility rates is to empower young women by educating them.”

At six billion plus today, the earth’s human population will reach more than nine billion by 2050, according to estimates. If this many people consume energy at the current rate in the developed world, the planet will need more than double the amount of power it consumes today. But energy is just one issue that humankind will have to tackle to create a sustainable future. The root cause of the looming energy problem--and the key to easing environmental, economic and religious tensions while improving public health--is to address the unending, and unequal, growth of the human population. And the one proven way to reduce fertility rates is to empower young women by educating them.

High fertility rates in areas of the developing world that can least cope put tremendous pressure on freshwater and sanitation needs and fuel economic and religious tensions. In response, these countries ramp up their energy production via the only means available to them based on their resources--means that tend to either pollute the environment or contribute to global warming. …

How Women Can Save the Planet

Technorati Tags: pollution

Teen birth rates highest in most religious states

Link may be due to communities frowning on contraception, researchers say

By Jeanna Bryner

U.S. states whose residents have more conservative religious beliefs on average tend to have higher rates of teenagers giving birth, a new study suggests.

The relationship could be due to the fact that communities with such religious beliefs (a literal interpretation of the Bible, for instance) may frown upon contraception, researchers say. If that same culture isn't successfully discouraging teen sex, the pregnancy and birth rates rise.

Mississippi topped the list for conservative religious beliefs and teen birth rates, according to the study results, which will be detailed in a forthcoming issue of the journal Reproductive Health. (See chart below.)

However, the results don't say anything about cause and effect, though study researcher Joseph Strayhorn of Drexel University College of Medicine and University of Pittsburgh offers a speculation of the most probable explanation: "We conjecture that religious communities in the U.S. are more successful in discouraging the use of contraception among their teenagers than they are in discouraging sexual intercourse itself." …

Teen birth rates highest in most religious states via Pharyngula

Technorati Tags: population

'Contraception cheapest way to combat climate change'

Contraception is almost five times cheaper as a means of preventing climate change than conventional green technologies, according to research by the London School of Economics.

By Richard Pindar

Every £4 spent on family planning over the next four decades would reduce global CO2 emissions by more than a ton, whereas a minimum of £19 would have to be spent on low-carbon technologies to achieve the same result, the research says.

The report, Fewer Emitters, Lower Emissions, Less Cost, concludes that family planning should be seen as one of the primary methods of emissions reduction. The UN estimates that 40 per cent of all pregnancies worldwide are unintended.

If these basic family planning needs were met, 34 gigatons (billion tonnes) of CO2 would be saved – equivalent to nearly 6 times the annual emissions of the US and almost 60 times the UK’s annual total.

Roger Martin, chairman of the Optimum Population Trust at the LSE, said: “It’s always been obviously that total emissions depend on the number of emitters as well as their individual emissions – the carbon tonnage can’t shoot down as we want, while the population keeps shooting up.”

UN data suggests that meeting unmet need for family planning would reduce unintended births by 72 per cent, reducing projected world population in 2050 by half a billion to 8.64 million. …

'Contraception cheapest way to combat climate change'

Technorati Tags: climate change,population,carbon dioxide

Family planning has major environmental impact

CORVALLIS, Ore. – 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. …

Family planning a major environmental impact

Technorati Tags: climate change,carbon dioxide,carbon footprint,population

Japan honours 'Limits to Growth' science author

TOKYO (AFP) — Japan on Thursday awarded its top science prize to a US researcher who decades ago predicted that rapid economic and population growth on a finite planet would lead to the collapse of civilisation.

Professor Dennis Meadows led a research team that in the 1972 study "The Limits to Growth," using a computer model called World3, forecast that on current trends humanity was headed for doom by 2100.

Meadows, of the US Massachusetts Institute of Technology, was the lead author of the study, which became a best-seller but was also attacked as alarmist and opposed to technology and progress.

Emperor Akihito watched Thursday as Meadows, 65, received the 500,000-dollar annual Japan Prize from the country's Science and Technology Foundation for "transformation towards a sustainable society in harmony with nature."

In his study, Meadows argued that "human demand exceeds nature's supply."

Unless the human race switched from exponential population and economic growth to a sustainable system, his team argued, they would "overshoot" the Earth's limits, leading to the collapse of human civilisation.

More than three decades on -- a time span in which the world population has grown from less than four billion to more than six billion -- Meadows said that today he sees even fewer signs of hope.

"In 1972, our projections suggested growth would end in this 21st century, and that still seems inevitable to me," he told a Tokyo conference this week.

"If demand against the planet rises above its carrying capacity, the carrying capacity will decline," he said.

"Growth will not end gradually and peacefully in the distant future. It will end soon and suddenly through overshoot and collapse." …

Japan honours 'Limits to Growth' science author

Technorati Tags: financial collapse,population,resource depletion,Peak Oil

‘Limits to Growth’ predictions surprisingly accurate after 37 years

From The Oil Drum:

This post relates to an article written by my advisor Charles Hall and a close friend of his. The article is available online, but is behind a paywall for nonacademic IPs.

There are only finite resources in the world, but population continues to grow. How will this situation resolve itself? This was a question a group of scientists (Meadows et al), commissioned by the "Club of Rome," attempted to answer back in 1972, in a book called Limits to Growth. The model they presented predicted growing resource scarcity, increasing pollution, and eventual population decline, all prior to 2100.

Charles A. S. Hall and John W. Day revisit these predictions in an article published this month in American Scientist called Revisiting the Limits to Growth After Peak Oil. Their analysis indicates that the predictions from 1972 were surprisingly accurate, considering how long ago they were made:

According to Hall and Day, "The values predicted by the limits-to-growth model and actual data for 2008 are very close." …

Limits to Growth Model Worth Another Look

Technorati Tags: resource depletion,population,Peak Oil