Interview: Designing Green Cities
To Meet 21st Century Challenges
Landscape architect Martha Schwartz is a passionate believer in the role that landscape can play in urban sustainability. Great landscape design, she says, can
Martha Schwartz Partners
moderate extreme heat, recycle water, reduce energy use, lower carbon emissions, and attract people to urban areas. Following these principles, her London-based firm, Martha Schwartz Partners
, has designed such projects as Dublin’s Grand Canal Square; Exchange Square, in Manchester, England; and Abu Dhabi’s Corniche beachfront area. In an interview with Yale Environment 360
, Schwartz, a professor at Harvard University’s Graduate School of Design, talks about the importance of incorporating cultural values in urban design, explains why the design of streets and parking lots is as important as the design of parks, and discusses why the U.S. lags behind many other nations in the greening of its cities. Read the interview
04 Dec 2012:
Air Quality Improvements
Continue to Yield Health Benefits
While the rate of improvement of U.S. air quality has slowed during the last decade, even those small improvements have had a beneficial effect on life expectancy, according to new research
. In a study of 545 counties across the U.S., researchers from the Harvard School of Public Health found that a slight decrease of fine particulate matter of 2.5 micrometers or less in diameter — known as PM2.5 — from 2000 to 2007 was associated with an average increase in life expectancy of 0.35 years. During that period, researchers say, concentrations of PM2.5 decreased by 10 micrograms per cubic meter. While that improvement in air quality was far less significant than the pollution reductions observed between 1980 and 2000, the new findings suggest that continued improvements have additional health benefits. “It appears that further reductions in air pollution levels would continue to benefit public health,” said Harvard researcher Andrew Correia, lead author of the study published in Epidemiology
28 Nov 2012:
Scientists Develop Standardized
Analysis of City Pollution Emissions
A team of Israeli researchers has developed a method to track pollution over the world’s mega-cities
, a satellite-based process they say could help hold nations accountable for their pollution and promote cleaner
Smog over Beijing
industrial practices. Using data collected by three NASA satellite systems, the researchers from Tel Aviv University (TAU) collected pollution trends for 189 cities with populations exceeding 2 million. According to Pinhas Alpert, head of TAU’s Porter School of Environmental Study, the research represents the first standardized global analysis of the smog levels in the atmosphere over the world’s largest cities. Based on the data, collected from 2002 to 2010, cities in Northeast China, India, the Middle East, and Central Africa saw the steepest rise in aerosol concentrations, with an average increase of 34 percent. The greatest improvements occurred in Houston, with a 31 percent decrease in aerosol concentrations; Curitiba, Brazil, a 26 percent decrease; and Stockholm, a 23 percent decrease.
21 Nov 2012:
Solar-Equipped ‘iShacks’ Offer
Cheap, Sustainable Housing in South Africa
South African researchers say they have developed a low-cost and sustainable housing alternative to the flimsy corrugated iron shacks found in the country’s growing settlements. Developed by an interdisciplinary
team at Stellenbosch University’s TsamaHUB center
, the so-called iShack is insulated with inexpensive, natural materials such as mud and cardboard boxes and has a sloped roof for harvesting rainwater. A photovoltaic cell on the roof provides the energy for motion-sensitive exterior lighting, interior lighting, and a cellphone charger. So far, a mother and her three children are living in a prototype iShack
in Ekanini, an informal settlement of 8,000 residents in Cape Town that lacks access to electricity and an adequate water supply. Project developers also taught six residents in the community how to install and maintain the solar power system in hopes they can use the skills for future entrepreneurial ventures. Researchers look to apply the iShack’s design to upgrade settlements in other regions.
19 Nov 2012:
Breeding Birds in UK
Have Declined 20 Percent Since 1960s
The population of breeding birds in the UK has plummeted by 21 percent since 1966
, losing more than 44 million birds in less than a half-century, according to the newly released State of the UK’s Birds 2012
report. According to experts, the number of house sparrows has
State of the UK's Birds 2012
The yellow wagtail
dropped from 30 million in 1966, when the first reliable bird-monitoring surveys were conducted, to about 10 million today — a loss of about 50 sparrows every hour. Once-abundant populations of the willow tit have all but disappeared in most regions of the UK, while numbers of the lesser spotted woodpecker and Arctic skua are now too few to number. Populations of farmland bird species are now half of what they were in 1970, according to the report, which draws on information from numerous bird surveys and databases. Land use changes and coastal water management have likely been key factors in these declines, as some species have had increasing difficulty finding suitable places to nest or forage, experts say.
In New York, The Rising Threat Of
Flooding Was Predicted for Years
While climate experts hesitate to say Hurricane Sandy was caused by climate change, scientists for years have predicted that such devastating events would become increasingly common as sea levels rise and ocean
Rising Currents: A 2010 exhibit showed visions of New York adapting to climate change.
temperatures become warmer. For more than a decade, reports have warned that climate change will likely trigger more intense hurricanes and more frequent and severe flooding in low-lying areas
, such as occurred in New York and New Jersey. And with sea levels projected to rise by as much as six inches per decade by mid-century and as much as several feet by 2100,
experts say New York City’s flood zone will continue to expand
. In Sandy's wake, New York officials are starting to discuss projects that might withstand such surges
, including building a levee system or barriers.
17 Oct 2012:
Elevated Levels of CO2
May Impair Cognitive Abilities, Study Says
Elevated levels of carbon dioxide in indoor settings can have a detrimental effect on decision-making abilities and work performance
, according to a new study. In a series of tests, U.S. researchers exposed 22 healthy adults to different levels of carbon dioxide concentrations (600 parts-per-million, 1,000 ppm, and 2,500 ppm) in an office-like room. Under each condition, the participants were asked to take a computer-based test that measured their decision-making abilities. According to the findings, published in the journal Environmental Health Perspectives
, the participants’ performance declined notably on six of nine tests when CO2 levels were increased to 1,000 ppm; performance declined substantially on seven of the tests when levels were bumped to 2,500 ppm. Earlier research has associated increased student absences and poorer performance with higher CO2 levels, said William Fisk, a researcher at the Lawrence Berkeley National Laboratory and co-author of the study. “But we never thought CO2 was actually responsible,” he said. “We assumed it was a proxy for other [pollutants].”
26 Sep 2012:
Approved for California Roadways
California Gov. Jerry Brown has signed a law that will allow self-driving vehicles on the state’s public roadways
by next year. While fully automated vehicle technology may be years away, the California law establishes safety and performance regulations for testing these cars next year — provided that the driver is ready to take control of the vehicle if needed. Several companies, including Google, are developing self-driving cars
that utilize a series of sensors — including GPS, cameras, lasers, and radar — as well as data from other vehicles to learn what is around the vehicle and guide its navigation. Developers say the innovative technology has the potential to improve safety, reduce congestion, and improve fuel efficiency. “We’re looking at science fiction becoming tomorrow’s reality,” said Brown, who drove to the signing ceremony at Google’s Mountain View headquarters in the passenger seat of a vehicle that steered itself.
24 Sep 2012:
Air Pollution in Europe
Shortening Lives of Urban Dwellers
Air pollution in Europe is shortening lifespans by an average of eight months
and by as much as two years in the most polluted cities and regions, according to a report from the European Environment Agency (EEA). While the European Union has cut emissions of many harmful pollutants over the last decade, the report finds that nearly a third of urban dwellers are still exposed to harmful levels of airborne particulate matter
, tiny pollutants small enough to penetrate the respiratory system and cause serious health ailments. About 21 percent of city dwellers are exposed to particulate matter above EU health standards. And 17 percent were exposed to higher levels of ozone, which can cause respiratory problems. “In many countries, air pollutant concentrations are still above the legal and recommended limits that are set to protect the health of European citizens,” said Jacqueline McGlade, executive director of the EEA. According to the report, humans living in industrial regions of Eastern Europe face the highest exposure to harmful pollutants.
18 Sep 2012:
Explosive Urban Growth
To Put Major Strain on Biodiversity
The world’s urban areas will expand by more than 1.2 million square kilometers by 2030
, nearly tripling the area of urban development that existed worldwide in 2000, according to a new study. That development surge, researchers say, will coincide with construction of new roads, buildings, and energy and water systems, causing considerable habitat loss in critical biodiversity hotspots — including many regions that were relatively undisturbed by development only a decade ago. Writing in the journal Proceedings of the National Academy of Sciences
, researchers from Yale, Texas A&M, and Boston University predicted that nearly half of that urban expansion will occur in Asia, particularly in China and India. Urban growth will occur fastest in Africa, they say, with a projected six-fold increase in land development compared with 2000. “Given the long life and near irreversibility of infrastructure investments, it will be critical for current urbanization-related policies to consider their lasting impacts,” said Karen Seto, an associate professor at the Yale School of Forestry & Environmental Studies and lead author of the study.
30 Aug 2012:
Better Use of Fertilizer, Water
Can Feed Growing Population, Study Says
A new study suggests that the the world can meet the surging demand for food in the coming decades without rampant deforestation if farmers make better use of fertilizer and water resources
. In an analysis of management practices and yield data for 17 major crops worldwide, researchers from McGill University in Montreal and the University of Minnesota estimated that yields for most crops can be increased 45 to 70 percent on lands already used for agriculture through more efficient fertilizer application and irrigation. Writing in the journal Nature
, the scientists found that the deployment of best-practice farming could boost global yields of corn, wheat, and rice by 64 percent, 71 percent, and 47 percent
, respectively. In some parts of the world, including the U.S., China, and Western Europe, the study found that far more fertilizer is used than necessary, with much of it ultimately washing into waterways. Through more efficient use of that fertilizer, nutrients could be made available for use in Eastern Europe and Western Africa without adversely affecting communities in the U.S. and China.
24 Aug 2012:
Drought Conditions Trigger
Smallest Gulf ‘Dead Zone’ in Years
U.S. scientists say the nation’s worst drought in five decades has had at least one positive effect: the smallest so-called “dead zone” seen in the Gulf of Mexico in years
. In a 1,200-mile research cruise conducted in the
Algal blooms in the Gulf of Mexico
waters of the gulf this month, scientists from Texas A&M University found only 1,580 square miles of oxygen-depleted, or hypoxic, water in the gulf, compared with 3,400 square miles last August. The hypoxic zone is created when algal blooms, caused by large amounts of fertilizer and nutrients washing into the gulf, remove oxygen from the water and suffocate marine life. According to the researchers, hypoxia was found only in the waters near the Mississippi River delta, which accounts for nearly 90 percent of all freshwater runoff in the gulf; no hypoxia was observed off the Texas coast. “What has happened is that the drought has caused very little fresh-water runoff and nutrient load into the gulf, and that means a smaller region for marine life to be impacted,” said Steve DiMarco, an oceanographer at Texas A&M.
15 Aug 2012:
Wildlife Vanishing in Brazil’s
Fragmented Atlantic Forest, Study Says
The fragmentation of tropical forests in eastern Brazil as a result of agricultural expansion and other human activities has decimated biodiversity even within the pockets of forest that still remain, a new study has found
. Using wildlife surveys and interviews conducted at 196 forest fragments across a 253,000-square-kilometer region inside Brazil’s Atlantic Forest, a team of researchers estimated that only about 22 percent of the animals that once inhabited the region are still there — far lower than earlier estimates
. According to their findings, published in the journal PLoS ONE
, white-lipped peccaries have been “completely wiped out,” while jaguars, lowland tapirs, woolly spider-monkeys and giant anteaters are essentially extinct. The loss of wildlife has even extended to areas where forest canopies are still relatively intact, said Carlos Peres, an ecologist at the University of East Anglia and lead author of the study. While the Atlantic Forest once covered more than 1.5 million square kilometers, about 90 percent has been cleared for agriculture, pasture, or urban expansion. Most remaining patches of forest, researchers say, are about the size of a football field.
13 Aug 2012:
Auto-Related Pollution in L.A.
Declined 98 Percent Over 50 Years
Levels of some automobile-related pollutants in Los Angeles have plummeted by 98 percent since the 1960s
, even as gasoline consumption nearly tripled during the same period, a new study says. Levels of volatile organic
compounds (VOCs), which are emitted from the tailpipes of cars and are a key ingredient in ground-level smog, have dropped steadily and fell by about half between 2002 and 2010, researchers found. “The reason is simple: Cars are getting cleaner,” said Carsten Warneke, a researcher at the University of Colorado and lead author of the study, published in the Journal of Geophysical Research
. Using data from the National Oceanic and Atmospheric Administration and California air quality measurements, the scientists calculated that VOC levels declined by an average of 7.5 percent per year. Researchers attributed the steep decline to the required use of catalytic converters, introduction of fuels less prone to evaporate, and improved engine efficiency.
01 Aug 2012:
Historic Blackouts Reveal
Troubling Holes in India’s Power Network
The historic blackouts that left more than 670 million people in India without electricity this week revealed profound problems with a power network struggling to keep pace with one of the world’s fastest growing economies, experts say. While it’s unclear what specifically triggered this week’s massive grid failures, which knocked out power in 20 Indian states
, government officials accused several northern states of drawing more power from the grid
than their allocated amounts. Another factor may have been increased electricity usage caused by unusually high water pumping for irrigation as a result of weak monsoon rains. Experts say the blackouts reveal a fundamental gap between supply and demand in a nation that aspires to be a global economic leader. While India has increased its power capacity more than 35 percent in the last five years, a peak-hour electricity shortfall of about 10 percent exists
and hundreds of millions of people in rural areas have no access to electricity. As much as two-thirds of India’s electricity comes from the burning of coal and some plants are struggling to meet demand because of a coal shortage.
12 Jul 2012:
Urban Noise May Increase
Mortality of Songbirds, Study Finds
A new study says that urban noise may cause an increase in mortality among young sparrows
, suggesting that adult birds are less able to hear their hungry offspring above the clamor of their surrounding environment. In a long-term study conducted on a small, remote island off the UK coast, scientists from the University of Sheffield found that birds nesting in noisy areas were less effective at feeding their chicks than those living in quiet areas, and actually produced fewer offspring. Chicks that were reared in a loud barn, for instance, were lighter when they were ready for flight, a factor that could affect a young bird’s chances for survival, said Julia Schroeder, co-author of the study published in the journal PLoS ONE
. “There are lots of studies on great tits and urban noise, but these tend to focus around mate choice, where the male advertises its quality to the female,” Schroeder told BBC News. “But the idea that the communication between parents and offspring could be affected in cities is fairly new.”
29 Jun 2012:
Recent Policies May Undermine
Brazil’s Green Progress, Scientists Say
Recent policies enacted by the Brazilian government — including changes to its Forest Code and a push to build 30 new dams in the Amazon region — threaten to undermine critical environmental progress made by the nation over the last two decades, scientists say. In a declaration
published after its annual meeting in Bonito, Brazil, the Association for Tropical Biology and Conservation
(ATBC) stated that government policies to reduce deforestation and protect indigenous lands had made Brazil a global conservation model over the last two decades. “But recent developments raise concerns,” said John Kress, a botanist at the Smithsonian Institution who is executive director of the ATBC. The group cited recent changes to Brazil’s forest protection laws that they say favor agribusiness and will likely increase deforestation in the Amazon, as well as numerous large-scale dam projects
that will interfere with critical fish migration routes and flood vast areas of rainforest and indigenous communities.
28 Jun 2012:
Cities in U.S. Northwest
Adopt Aggressive Recycling Programs
Seattle, San Francisco, and Portland, Ore., have all adopted stringent recycling programs that have generally been embraced by citizens in these progressive cities and have significantly reduced the amount of garbage going to landfills
. The New York Times
reports that Portland has cut the amount of garbage going to landfills by 44 percent by recycling a wide range of materials, including food scraps, and collecting garbage only twice a month. San Francisco, which has adopted even more aggressive recycling initiatives, now reuses 78 percent of what enters its waste stream, compared with the national average of 34 percent. This summer, Seattle is opening a mammoth new waste transfer station that will enable it to sort through and recycle a large portion of its garbage, the Times
reports. With citizens in these relatively small cities — all with populations under 800,000 — pushing for a zero-waste policy, Seattle says that by 2018 it will even provide some neighborhoods with containers to recycle dog and cat waste, turning the excrement into power using anaerobic digests.
26 Jun 2012:
Elevated Ozone Levels
Trigger Heart Risks for Healthy Adults
Exposure to ozone at levels sometimes present in the world’s most polluted cities can trigger potentially dangerous changes to human cardiovascular systems, according to a new study
. In a series of tests conducted
Mexico City smog
on 23 healthy adults, scientists found evidence of cardiac inflammation and heart rhythm disturbance after exposure to air containing ozone at 0.3 parts per million for two hours — about the same dose they would receive if exposed to ozone levels exceeding the U.S. standard of 0.075 parts per million over eight hours. According to the findings, published in the journal Circulation
, the blood levels of several inflammatory agents increased — more than doubling in some cases — after ozone exposure. This finding “caught us by surprise,” said Robert Devlin, a toxicologist with the U.S. Environmental Protection Agency and lead author of the study. “We think it’s one of the more important and significant findings.” Heavily polluted cities such as Beijing and Mexico City often have extremely high ozone levels, and ozone in U.S. cities such as Los Angeles and Houston can reach levels equal to those used in the experiment.
19 Jun 2012:
Major World Cities
Cite Progress in CO2-Reduction Effort
Speaking at the Rio+20 sustainability summit, the mayors of New York City and Rio de Janeiro will announce that 48 of the world’s largest cities are taking steps to cut 248 tons of greenhouse gas emissions by 2020
, the equivalent of removing 44 million cars from the road for a year. New York Mayor Michael Bloomberg and Rio de Janeiro Mayor Eduardo Paes said that four-dozen cities in the C40 Cities Climate Leadership Group
are reducing emissions by launching energy efficiency programs, capturing methane in landfills, installing more efficient street lighting, and other initiatives. They cite the CO2 reductions as proof that cities can make significant progress on slashing greenhouse gases even in the absence of a global agreement on cutting carbon emissions. “We’re not arguing with each other about emissions targets,” Bloomberg told reporters in a teleconference. “What we’re doing is going out and making progress.” Bloomberg and Paes said that 59 cities have committed to cut their carbon emissions by a total of 1 billion tons by 2030, equivalent to the combined greenhouse gas emissions of Canada and Mexico.
19 Jun 2012:
Being Killed at Alarming Rate, Report Says
At least one person is killed per week in disputes over environmental protection or land rights as the competition for natural resources globally becomes increasingly violent, according to a new report
. In a survey of incidents worldwide, the group Global Witness estimated that 711 environmental activists, journalists or community members have been killed during the last decade over disputes involving land and forest rights. In 2011 alone, the number was 106, which was twice the number of killings in 2009. The report's authors say it provides a stark reminder of a “hidden crisis” and highlights a culture of impunity and a lack of oversight in many countries. The greatest number of killings reportedly occurred in Brazil, Colombia, the Philippines and Peru. “It is a well-known paradox that many of the world's poorest countries are home to the resources that drive the global economy,” the report said
. “Now, as the race to secure access to these resources intensifies, it is poor people and activists who increasingly find themselves in the firing line.”
07 Jun 2012:
Environmental Tipping Point
Is Nearing, International Study Says
The rapid warming of the planet, a soaring human population, the steady loss of biodiversity, over-exploitation of energy resources, and the degradation of the world’s oceans are driving the world toward an ecological tipping point,
according to a new study in Nature
. Twenty-two scientists from five nations compared the major changes taking place today with previous ecological shifts — such as the end of the last Ice Age 14,000 to 18,000 years ago — that triggered mass extinctions of some species, expansions of others, and the creation of new global ecosystems. The paper said that while there is still considerable uncertainty as to whether the world is now approaching such a “state shift,” many signs point to a future of ecological upheaval. “Given all the pressures we are putting on the world, if we do nothing different, I believe we are looking at a time scale of a century or even a few decades for a tipping point to arrive,” lead author Anthony Barnosky
, a biologist at the University of California, Berkeley, said in an interview.
29 May 2012:
Wind Farms Consider
Radar Systems to Prevent Bird Deaths
The operators of large California wind farms are considering the use of advanced radar and telemetry systems to reduce the number of birds killed
by spinning turbines located in critical migration pathways. The so-called avian radar systems, which
American Bird Conservancy
have been deployed at wind farms in Texas and Europe, would be able to identify birds early enough to shut down the turbines, at least briefly, to prevent collisions. Advocates say the systems could prevent large-scale killings of many migratory songbird species, as well as the critically endangered California condor and the federally protected golden eagle. According to the Los Angeles Times
, one possible customer for the radar systems is the Los Angeles Department of Water and Power, which operates a wind farm that is under federal investigation following the discovery of several dead golden eagles at the site. “Renewable energy operators are coming around to the view that they have to do something,” said Gary Andrews, chief executive of De Tect Inc., a manufacturer of such systems. The systems, however, are expensive, at $500,000 per unit, and existing technologies typically have difficulty differentiating among bird species.
23 May 2012:
Street Lights Can Cause
Long-Term Ecological Changes, Study Says
The presence of artificial street lights can alter the behavior of ground-dwelling invertebrates and insects
and ultimately change the structure and function of some ecosystems, according to a new study. In a series of tests in Cornwall in western England, researchers from the University of Exeter used 28 traps to capture 1,200 animals on the ground beneath street lights and in darker areas between the lights. According to their findings, published in the journal Biology Letters
, invertebrate predators and scavengers were more common underneath the lights, even during the daylight hours. Thomas Davies, a researcher at the University of Exeter and lead author of the study, said these findings suggest that nocturnal behavior is affecting habitat preference overall, and could have implications for critical ecosystem services, including pollination and the breakdown of organic matter. “It’s amazing how long we’ve been using street lighting and artificial lighting, and how little research has been done on the impact of those lights on the environment,” he told BBC News
30 Apr 2012:
Australia Lists Koala As
Threatened Species for First Time
The Australian government has added the koala to the list of threatened species
in parts of the country for the first time, saying the iconic species is under threat from habitat loss, urban expansion, disease, and climate change. Following a three-year study, Environment Minister Tony Burke announced
that koalas will be listed as vulnerable in Queensland, where populations have declined by 40 percent in two decades; New South Wales, where numbers have dropped by one-third; and the Australian Capital Territory. In addition to the listing, which will impose restrictions on development in areas where the species is threatened, the government committed $300,000 for koala monitoring and habitat research. Not only are koalas facing declining food sources as eucalypt plants are aggressively cleared for development, but scientists say the nutritional value of remaining eucalypts has diminished as a result of climate change. While the government says there are about 200,000 remaining koalas nationwide, the Australian Koala Foundation estimates there are likely fewer than 100,000.
16 Mar 2012:
Africa Could Produce
More E-Waste Than Europe by 2017
Africa, typically a dumping ground for electronic waste from other nations, could produce more e-waste than the European Union by 2017
, experts say. Across Africa, a combination of population growth and increased access to mobile phones and other technology will produce a surge in e-waste over the next five years, Miranda Amachree of Nigeria’s National Environmental Standards and Regulations Enforcement Agency told reporters at the Pan-African Forum on E-Waste. While the continent has long received thousands of tons of waste for disposal from developing nations, a recent report by the UN Basel Convention found as much as 85 percent of Africa’s e-waste is now local. That report
found that in five West African nations ten times as many people have personal computers as a decade ago, and 100 times as many people have cellphones. In those countries alone, as much as 1 million tons of domestic e-waste is now generated per year. Katharina Kummer Peiry, of the Basel Convention, said African nations must “move towards more formal recycling in order to ensure precious metals are properly extracted from, say, mobile phones.”
08 Mar 2012:
New York Roof Study Shows
Drastic Cooling with White Surfaces
A New York City roof covered in a white synthetic membrane was on average 43 degrees F cooler than surrounding black tar and asphalt roofs
during times of peak heat last summer, according to a study by scientists from Columbia University and NASA. On the
hottest day of the summer — July 22, 2011, when the city set a record for electricity usage during a heat wave — the dark surfaces of some city roofs reached 170 degrees F, while temperatures on the white test roof peaked at less than 130 degrees F. The city’s CoolRoofs initiative
is working to install “living roofs” with plants and to convert many tar and asphalt roofs to a white color using membranes or white paint. The goal, the city says, is to help reduce the urban “heat island” effect, which can boost temperatures by 5 to 7 degrees F, especially at night. Lowering the heat island effect would reduce demand for air conditioning and cut illnesses and deaths during heat waves. Converting roofs to white is cheaper than planting “living roofs,” the researchers noted. “Bright is the new black,” said Stuart Gaffin, a Columbia scientist and lead author of the study, which was published in the journal Environmental Research Letters.
15 Feb 2012:
Short-term Exposure to Pollutants
Increases Heart Attack Risk, Study Says
A new report says that even short-term exposure to major air pollutants increases the risk of heart attack
. In an analysis of more than 100 studies conducted worldwide, researchers from the Paris Cardiovascular Research Center found that increased exposure to pollutants — including fine particles, coarse particles, nitrogen dioxide, carbon monoxide, and sulfur dioxide — consistently increased the health risks after even short-term exposure, or less than seven days. While the risk from pollutant exposure was relatively small, compared with factors such as high blood pressure, the number of people breathing these pollutants worldwide is so large that a sizable number of people are at risk, the study said. In the case of fine particles, the researchers found that heart attacks increased 2.5 percent for every incremental increase in pollution levels. In other words, if fine particle levels reached 10 micrograms per cubic meter in one city, and 20 micrograms in another, the rate of heart attacks would be 2.5 percent greater in the second city, according to the study, published in the Journal of the American Medical Association
. Most of the pollutants are associated with the burning of fossil fuels for transportation or industry. In a separate study, MIT researchers found that air pollution associated with China’s steep industrial growth caused health care costs to jump from $22 billion in 1975 to $112 billion in 2005
13 Feb 2012:
Electric Vehicles in China
Pollute More Than Gas-Fueled Cars
The use of electric cars in China produces more particulate matter pollution than gasoline-fueled vehicles
, according to a new study. In an analysis of five vehicle technologies in 34 major Chinese cities, U.S. researchers found that the power generated to run electric cars produces significantly greater particulate matter emissions because 80 percent of China’s electricity comes from coal-burning power plants. While those plants are typically located far from population centers, the researchers nevertheless found that the difference in pollution is so great that electric vehicles are still more harmful to the public health per-kilometer traveled than conventional vehicles. The study, published in the journal Environmental Science and Technology
, emphasizes that electric vehicles are a cleaner option if powered by a clean energy source. “In China and elsewhere, it is important to focus on deploying electric vehicles in cities with cleaner electricity generation and focusing on improving emissions controls in higher polluting power sectors,” said Chris Cherry, a researcher at the University of Tennessee, Knoxville, and lead author of the study.
10 Feb 2012:
Wastewater Reuse Could Increase
U.S. Supplies 27 Percent, Report Says
Advanced treatment of municipal wastewater could increase available water supplies in the U.S. by 27 percent, according to a recent report by the National Academy of Sciences
. Of the 32 billion gallons of municipal wastewater discharged each day nationwide, about 12 billion gallons of effluent is emptied into an ocean or estuary, the report said. Existing treatment technologies would allow municipalities to reuse that water for a variety of purposes — including irrigation, industrial use and drinking water — while posing no increased risk of exposure to microbial or chemical contaminants than in some existing drinking water systems. As reported in the New York Times
, an increasing number of U.S. communities are utilizing wastewater reuse technologies — including a pilot plant in San Diego that produces about 1 million gallons of clean drinking water daily — or are considering it. According to the National Academy report, increased stress on water supplies as a result of climate change and population growth will require many municipalities to consider alternative sources of water.