Tuesday, November 30, 2010

Traffic, Air Pollution and Heart Disease in Vancouver

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Long-Term Exposure to Traffic-Related Air Pollution and the Risk of Coronary Heart Disease Hospitalization and Mortality (39 page pdf, Environ Health Perspect., Nov. 16, 2010)

Key Quotes:

“To identify specific traffic-related air pollutants that are associated with the risk of coronary heart disease (CHD) morbidity and mortality to support evidence-based environmental policy making”

“used a high-resolution LUR model combined with residential histories to estimate individual exposure to traffic-related air pollutants including black carbon, PM2.5, NO2, and NO during the 5-year exposure period”

“Long-term exposure to traffic-related fine particulate air pollution, indicated by black carbon, may partly explain the observed associations between exposure to road traffic and adverse cardiovascular outcomes”


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Monday, November 29, 2010

Impact of Air Pollution on Health

The Health Effects of Air Pollutants (59 slide pdf, 6th Annual Workshop on Air Pollution and Health, Jun. 15, 2009)

Also discussed here:

(2 min YouTube video)

Key Quotes:

“A recent Canadian Medical Association estimate for BC residents projected 306 premature deaths (of which 85% relate to long-term exposure), and 1158 hospital admissions for 2008 through exposure to air pollution”

“Long-term particulate exposure is associated with:

  • More frequent preterm births and low birth weight babies

  • Middle ear disease in children

  • Accelerated heart and lung disease”

“Short-term exposure results in:

  • Increased rates of myocardial infarction for those with risk factors for heart disease

  • Heart rate disturbances

  • Episodes of acute asthma and bronchitis

  • Reduced lung function”

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Friday, November 26, 2010

How Critical is Population Density for Public Transit?

Although an important factor, there is a compl...
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http://mams.rmit.edu.au/j4oa4rdaow29.pdf (13 page pdf, State of Australian Cities Conference, Perth, 25 November 2009)

The author of the article under review today analysed density and transport patterns in Canada, the US and Australia He challenges the long-used assumption by urban planners that the viability of transit depends on high urban population density, pointing out that transportation policy can be changed much more rapidly than the built environment which is required for higher densities. He concludes that a much better measure of urban population density is needed to assess public transit potential and, on the other hand, car usage for commuting.

Key Quotes:

“For at least two decades, urban policy in Australia has been based on the belief that high levels of car use and poor public transport are mainly the result of low urban densities”

“Some cities (e.g.Brisbane) contain large areas of vacant land within their boundaries, while others (e.g. the City of Toronto) occupy only the inner part of the urbanised area. Therefore, more accurate density measures are needed”

“Far from being the archetype of sprawl, Los Angeles has the highest density of any urban area in the table, just edging out Toronto and San Francisco, and significantly higher than other Canadian and US cities”

“The US cities, apart from New York, have the lowest rates of public transport use and the Canadians the highest, with Australia in-between”

“Car usage rates are.. lowest in Canadian cities and New York; highest in the United States. Again, density is a poor predictor of car usage rates: New York and Ottawa are the only cities where the figure is below 70 per cent, but do not have particularly high densities”

“densities as low as 12 people per hectare would be sufficient to support an unsubsidised rail service supported by feeder buses, provided the railway serves a strong centre with a significant share of the region’s jobs and activity”

“the compact city is unlikely to solve the problem of automobile dependence, as the increases in density required to significantly change transport patterns on a metropolitan scale are impossible to achieve”

“we don’t need impossible increases in density to provide viable alternatives to the car. The relative attractiveness of competing urban transport modes seems to influence mode choice much more than differences in density”

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Thursday, November 25, 2010

Road Diet- putting a curb on roads

A person rides a bicycle in a diamond lane in ...
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Road Diets Fixing the Big Roads (15 page pdf, Walkable Communities, Inc. March 1999)

Also discussed here: Applying the Road Diet for Livable Communities (20 slides, ITE, 2005)

And here Summary Report: Evaluation of Lane Reduction "Road Diet" Measures and Their Effects on Crashes and Injuries(6 page pdf, Highway Safety Information System, US Dept of Transportation)

And here: Road diet (Wikipedia)

And here:  The Benefits of a “Road Diet” (StreetsBlog, May 3, 2007)

One well recognized axiom of road design is that the wider they become the more traffic and congestion can be expected. The counter to this is to improve traffic flow not by widening the roads but by reducing their width and lanes- a concept called “Road Diet”. Results show fewer fatalities form crashes and one might expect lower emissions as a result of less congesiton and the idling that accompanies stalled traffic. The replacement of vehicle lanes with cycling lanes also contributes to a less polluting city and safer riding for cyclists. Pedestrians too are safer not having as wide a street to cross as before, with a safe median as a refuge in the middle of the road. Is the four lane road an antiquated design whose time has come and gone?

Key Quotes:

““Road dieting” is a new term applied to “skinnying up” patients (streets) into leaner, more productive members of society. The ideal roadway patient is often a four-lane road carrying 12-18,000 auto trips per day”

“Pedestrians have rugged times finding gaps across four lanes. Crash rates and severity of conflicts with autos result in almost certain death (83% of pedestrians hit at 40 mph die)”

“Researchers have found that road diets can be expected to reduce crashes by 6% to 29%”

“The change can increase value of existing properties. In some cases costs of reconstructing roadways are repaid in as little as one year through increased sales tax or property tax revenue”

Best places to start:

  • “Moderate volumes (8-15,000 ADT)

  • Roads with safety issues

  • Transit corridors

  • Popular or essential bicycle routes/links

  • Commercial reinvestment areas

  • Economic enterprise zones

  • Historic streets

  • Scenic roads

  • Entertainment districts

  • Main streets”

“In Toronto, we have removed traffic lanes on approximately 18 km (12 miles) of downtown streets (eight different streets) to provide bike lanes. These routes represent about two thirds of our existing bike lanes”

“We have a project in Ottawa where a bridge is being reconstructed. The original cross-section included two HOV (buses only) lanes and four car lanes (2 in each direction). The new cross-section includes two HOV buses only) in the outside lanes, then two car lanes and two bicycle lanes (one in each direction). A median was also added. In essence, two car lanes were given over to bicycle lanes and a median”


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Wednesday, November 24, 2010

Greening Cities with Immigrants

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From a “Green Farce” to a Green Future - Refuting False Claims About Immigrants and the Environment (21 page pdf, Center for American Progress, Oct. 2010)

Immigration is a sensitive political issue in many countries, particularly in the report reviewed today which focuses on the situation in the USA.  The report challenges claims that immigrants cause or contribute to environmental degredation, especially regarding the difficulty faced by climate change policy makers in getting Americans (and Canadians, I dare say) to adopt less polluting life styles and shift energy use off carbon sources. Once again, the role of cities is seen as crucial in finding solutions – in addition to encouraging more, rather than fewer, immigrants with inherently greener outlooks. What is not discussed in the report is the environmental record of countries and the societies from where the immigrants come – which might reveal a not surprising link between lower standards of living and lower consumption, for example, which might change when the immigrant becomes part of a higher income, higher polluting society.

Key Findings:

  • “The 10 highest carbon-emitting cities have an average immigrant population below 5 percent

  • The cities with the lowest carbon footprint have an average immigrant population of 26 percent.

  • Immigrants.. are more likely to use public transportation and practice sustainable habits like compact living, conservation, and recycling.

  • Immigrants, who are largely low income, are also more likely to have their lives disrupted by extreme weather events and other adverse effects of climate change.

  • Addressing climate change and poverty on a global scale will help stabilize immigration flows from undeveloped countries.

  • Immigrants are disproportionately hurt by the dirty energy economy and face unique environmental challenges

  • Immigrants ..accounted for 70 percent of men and women who entered the engineering and science fields”

Key Energy Facts:

  • “Thirty-eight percent of U.S. GHG emissions come from buildings.

  • Commercial and industrial buildings account for as much as 50 percent of U.S. energy use and residential buildings account for another 20 percent.

  • Twenty-nine percent of U.S. GHG emissions come from transportation.

  • Seventeen percent of global GHG emissions are caused by deforestation.

  • Fifty-seven percent of global GHG emissions are caused by burning fossil fuels.

  • The United States meets 85 percent of its energy needs by burning fossil fuels”

Key Recommendations:

  • “mandatory annual electricity and natural gas consumption reduction targets for utilities—can save 262 million metric tons of greenhouse gas emissions.

  • Expand renewable energy. ..Remarkably, only 7 percent of our current national energy portfolio comes from renewable sources

  • Curb deforestation. Tropical deforestation is responsible for more emissions than all the cars, trucks, planes, and ships in the world combined.

  • Limit fossil fuels..include improved fuel economy standards, development of advanced bio-fuels, incentives for nonpolluting electric vehicles, and use of natural gas.

  • Plan smart cities…include widely available mass transit and walking-bicycle paths (to curb vehicle travel), compact residential and commercial development (to curb overuse of open space), and efficient use of electricity and water through networked resource management, also called a “smart grid.”

“The reality is that our environmental impact is not just determined by our numbers, but how we use resources—how we produce and consume energy, and what policies we put in place to shape these decisions“

“the world will be utterly unable to solve its significant environmental challenges so long as problems of global importance are viewed through a narrowly nationalistic lens”

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Tuesday, November 23, 2010

Powering Small Smart Devices with Light and Motion

Image representing iPad as depicted in CrunchBase
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University of Bolton scientists create smart material to generate energy from the elements (ASM International, Nov. 3, 2010)

Also discussed here: Scientists Create Photovoltaic-Piezoelectric Fiber To Power Gadgets With Light & Motion (The Green Optimistic, Nov. 2, 2010)

And here: Photovoltaic-Piezoelectric Fiber Could Power Your Laptop (Solar Novus, Nov. 1, 2010)

And here: University of Bolton researchers create hybrid solar energy-generating fiber (Solar Server, Oct. 28, 2010)

The explosion taking place in the number of low-powered smart appliances and their need to be recharged has resulted in an overall increase in demand for electrical power. When this demand is multiplied across a city or country, it translates into the need for more power generation from polluting sources, such as coal and natural gas. The invention by researchers in the UK and China gathers energy from the sun and motion in a fibre which could be applied easily in many if not most small smart devices.

Key Quotes:

“scientists developed a flexible piezoelectric fiber that can harness motion, but now they’ve upgraded the fiber, making it capable to transform the material into a solar energy source.”

“the fiber can be woven into energy-harvesting fabrics, and has the potential to produce electricity from sunlight as well as motion, including wind and wave action”

“The most immediate applications will be in the area of low-power microelectronic-driven devices like mobiles, laptops, MP3s, Ipads - anything that requires re-chargeable batteries or small batteries to run”

“can currently produce one watt from a 20cm by 20cm square of the material…When you consider a low-energy light bulb uses nine watts you can see that now, even in its early development stages, the material is producing credible power.”

“The advantage of a hybrid photovoltaic and piezoelectric cell is that it can generate energy when there is no sunlight on a rainy or windy day, by using wind and rain energy”

“At home, a tree with needle like-fibers, could be converting sun, wind, and rain into electrical energy, which is stored ready for charging,”

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Monday, November 22, 2010

Long Time Exposure to Traffic Pollution and COPD

Age-standardised disability-adjusted life year...
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Chronic Obstructive Pulmonary Disease and Long-Term Exposure to Traffic-Related Air Pollution: A Cohort Study (Abstract, American Journal of Respiratory and Critical Care Medicine., Sep. 24, 2010)

Also discussed here: Air Pollution Exposure Increases Risk of Severe COPD (Science Daily, Nov. 5, 2010)

Key Quotes:

“Long term exposure to low-level air pollution may increase the risk of severe chronic obstructive pulmonary disease (COPD)”

“estimated pollution exposure by linking residential addresses to outdoor levels of NO2 and NOx levels, which were used to approximate the overall level of traffic-related pollutants since 1971. They looked at exposures over 15-, 25- and 35-year periods to assess the effect of different exposure lengths on COPD incidence”

"When we adjusted for smoking status and other confounding factors, the association remained significant, indicating that long-term pollution exposure likely is a true risk factor for developing COPD."

“effect of air pollution on COPD was strongest in people with pre-existing diabetes and asthma”

"In any case, sufficient data, including the results of this study, provide evidence that traffic-related urban air pollution contributes to the burden of COPD and that reductions in traffic emissions would be beneficial to public health."

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Friday, November 19, 2010

3D Forecasts of Air Quality – PREV’AIR

PREV’AIR -An Operational Forecasting and Mapping System for Air Quality in Europe (11 page pdf, Bulletin of American Meteorological Society, Jan. 2009)

Also discussed here: PREV’AIR

Key Quotes:

“[French] local authorities in charge of air pollution can now inform the public and take emergency decisions related to air pollution control not only on the basis of measurements, but also by accounting for numerical forecasts”

“three main functions of the PREV’AIR system:

  1. The “forecasting” function delivers forecasted atmospheric concentrations of ozone, particulate matter (PM10 and PM2.5), and nitrogen oxides, simulated throughout Europe at low resolution (0.5° × 0.5°) and over France with a higher resolution (0.15° × 0.1°).

  2. The “analysis” process uses available near-realtime observations to build the “analyzed” maps that are considered as the most realistic description of pollution patterns.

  3. The “performance evaluation” function of the system uses observation data that are routinely acquired for continuous evaluation of the model forecasts, with descriptive indicators given online. Every day, statistical skill scores (bias, errors, percentage of errors lower than a certain level, and correlation) are calculated and updated on the PREV’AIR Web site”

“In case of a pollution episode, when concentrations exceed the regulatory thresholds, PREV’AIR forecasts are broadcast on television channels to enhance public information.“

“system provides real-time information about air pollutant concentrations throughout Europe, with a focus on France, which is particularly relevant to health prevention in acute pollution episodes.“

“Air quality forecasting and mapping is an efficient tool for authorities in charge of air quality management. Anticipating pollution events with concentrations exceeding regulatory levels allows them to inform the general public and to decide emergency control measures.”

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Thursday, November 18, 2010

Health and Urban Poverty

Meeting the Health Challenge of Urban Poverty and Slums (62 minute streaming video, Woodrow Wilson Center, Jul. 20, 2010)

Also discussed here: Urbanization and Health: challenges and promises (23 slide pdf, Woodrow Wilson Center's Environmental Change and Security Program, Jul. 20, 2010)

Today’s review article looks at the health challenges of the urban poor, noting that this is likely to grow as urban populations grow from 50% of the world’s population to 70 % in the next 40 years. Poorer areas of individual cities are more likely to suffer from more pollution of the air and water in particular, as well as cities in poorer countries in warmer climates. Also of note is the need to look at individual city characteristics and requirements rather than acting on general assumptions.

Key Quotes:

“170 million urban residents currently do not have access to a latrine and over 1.2 million people will die from urban air pollution this year.”

“While urban centers have the most hospitals and attract many of the best doctors, the hospitals are often not managed or governed well. As a result, many urbanites suffer worse health care than their rural neighbors.”

“as the world transforms from a rural to an urban planet, it is essential for emerging and growing cities to use successful urban development examples from both the Global North and the South.”

“you’ve got to do analytical work to see what the problems are in each city and to look not at the averages but to unmask the differentials.”

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Wednesday, November 17, 2010

Reporting Climate Change - Carbon Footprints for Cities

Carbon Disclosure Project - The Case for City Disclosure(24 page pdf, Accenture, Carbon Disclosure Project, Nov. 2010)

Also discussed here: CDP Pushes Cities to Disclose Their Climate Impact (Triple Pundit, Nov. 2, 2010)

Cities are now the home for more than 50% of the world’s population (predicted to rise to 60 percent by 2030, and 70 percent by mid-century, according to UN figures) and generate as much as 80% of the greenhouse gas emissions. Curbing the damaging aspects of climate change will depend on cities taking action to adapt or mitigate the impacts and to reduce carbon emissions. The report reviewed today describes a disclosure system used for reporting emissions by companies world wide that could be used for cities.

Key Quotes:

" Cities only occupy about 2% of the world's land, but house half of its population....could contribute up to 80% of the globe's total emissions"

“the inhabitants of some cities have an increased likelihood of climate change-related health issues, such as heat exhaustion and increased incidence of tropical disease provoked by rising temperatures”

“Cities have the unique ability to respond to a global issue like climate change at a local, more visceral level, and cities usually offer more immediate and effective communication between the public and decision makers. Cobenefits of climate change mitigation and adaptation schemes are largest in cities” (World Bank)

“climate change reporting can become an essential component to enable cities to:

  • Drive economic competitiveness through the realization of operational efficiencies and the attraction of investment and innovation;

  • Improve climate change risk management;

  • Demonstrate the value of cities’ sustainability strategies to society”

“Cities are using climate change action plans as a means to overhaul ageing infrastructure, engage and educate their residents, generate new jobs and businesses, and implement broad, far-reaching sustainability agendas”

“Each city is different and faces distinct challenges in reducing GHG emissions. Cities should not be judged simply on a series of quantitative metrics, but on a complete picture of the unique situation of the city”

“A recent study for the City of Chicago estimated the total cost impact of anticipated climate change on city departments and functions for the 2010–2099 period is $2.54 billion under a “high-emissions scenario” and $690 million under a “low-emissions scenario.”

“The city mapped Chicago’s hottest spots and overlaid a map of phone calls regarding heat-related emergencies to assess the correlation between the urban heat island and heat stress-related issues to help inform its cooling and energy efficiency strategies”

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Tuesday, November 16, 2010

The Changing Meaning of Sustainability

Definitions of sustainability often refer to t...
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What is Sustainability? (13 page pdf, Sustainability 2010, 2(11), 3436-3448, Nov.1, 2010)

The authors of the article under review today tackled a large challenge in examining what “sustainable development” meant when introduced in 1987 by the Brundtland Commission and what it has become in being applied with such concepts as Triple Bottom Line. Indeed, “Sustainable Cities” was considered for the title of this blog but discarded in preference to a clearer “Pollution Free Cities” where the link to sustainability is expected from striving for a city without pollution- a term which, unlike sustainability, is measurable. The other main point made in the article is the lack of priority given to the environment compared to socio-economic trends which also tend to be viewed short term “happiness” as opposed to the long term well being implied in maintaining a high quality environment.

Key Quotes:

“The concept of sustainability was originally coined in forestry, where it means never harvesting more than what the forest yields in new growth.. is a natural topic of study for economists: after all, the scarcity of resources is of central concern to the dismal science”

“two major developments in the concept of sustainability:

  • its interpretation in terms of three dimensions, which must be in harmony: social, economic and environmental.

  • the distinction between ‘strong’ and ‘weak’ sustainability”

“Sustainability ..was concerned with the tension between the aspirations of mankind towards a better life on the one hand and the limitations imposed by nature on the other hand.. re-interpreted as encompassing three dimensions, namely social, economic and environmental.. obscures the real contradiction which exists between long-term sustainability and short-term welfare.”

“return to the original meaning, where sustainability is concerned with the well-being of future generations and in particular with irreplaceable natural resources—as opposed to the gratification of present needs which we call well-being”

“If ‘sustainability’ is anything more than a slogan or expression of emotion, it must amount to an injunction to preserve productive capacity for the indefinite future”

“Happiness, Well-being and Welfare.. may be used to express a primary goal of government policy: to improve people’s lives”

“view happiness as a basic goal of human behaviour but not of policy.. well-being refers to the objective conditions that help to make people happy..equivalent to ‘livability of the environment’.. Welfare is then a more limited concept denoting prosperity in terms of material needs such as food, water, health, and shelter.

“Sustainability may then be defined as maintaining well-being over a long, perhaps even an indefinite period. This covers largely the environmental dimension of the triple bottom line, but environment and sustainability are not synonymous”

“should pose two questions: what resources should we preserve at all cost, and to what degree?.. Sustainability, then, is a matter of what resources—natural resources, quality of the environment, and capital—we bequeath to coming generations”

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Monday, November 15, 2010

Atmospheric Chemistry Processes in Smog Formation

Predicting Smoggiest Days: Experiments Improve Accuracy of Ozone Predictions in Air-Quality Models (Science Daily, Oct. 28, 2010)

Also discussed here: Rate of Gas Phase Association of Hydroxyl Radical and Nitrogen Dioxide (Abstract, Science, Vol. 330. no. 6004, pp. 646 – 649, Oct. 29, 2010)

Key Quotes:

“The reaction of OH and NO2 to form gaseous nitric acid (HONO2) is among the most influential in atmospheric chemistry….We demonstrate the impact of the revised value on photochemical model predictions of ozone concentrations in the Los Angeles airshed.”

“The key reaction in question in this research is between nitrogen dioxide and the hydroxyl radical.. Until about the last decade, scientists thought these two compounds only combined to form nitric acid, a fairly stable molecule with a long atmospheric life that slows ozone formation”

“researchers found the loss of hydroxyl radical and nitrogen dioxide is slower than previously thought-although the reactions are fast, fewer of the radicals are ending up as nitric acid than had been supposed, and more of them are ending up as peroxynitrous acid.”

"a small but significant impact on the predictions of computer models used to assess air quality, regulate emissions and estimate the health impact of air pollution,"

“the laboratory results suggest that, on the most polluted days and in the most polluted parts of L.A., current models are underestimating ozone levels by 5 to 10 percent”

“a 10 part-per-billion increase in ozone concentration may lead to a four percent increase in deaths from respiratory causes-any increase in expected ozone levels will be important to people who regulate emissions and evaluate health risks”

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Friday, November 12, 2010

Modelling Air Quality in an Urban Canyon

Estimation of CO concentrations for an urban street canyon in Ireland (8 page pdf, Air Quality, Atmosphere & Health, Mar. 5, 2010)

Today’s review article looks at the performance of two canyon air quality models – STREET and OSPOM – when compared with stationary monitor located near a busy roadway in Dublin. In addition an assessment is made using emission factors (HEF for hourly and CEF for Composite) to judge the models as to the emissions from the source

Key Quotes:

“The WHO has estimated that 1.4 billion urban residents in developing countries breathe air in which pollutant concentrations exceed WHO air quality guidelines (WHO 1992). Urban air pollution episodes are associated with sudden incidences of high concentrations of pollutants, which are generally governed by local meteorology, emissions and dispersion conditions (Mayer 1999). The major source groups responsible for urban air pollution are primarily motor traffic and industries”

“In most European cities, traffic is the most important source of air pollution, with the highest ambient concentrations often found on streets in urban centres. Vehicular pollution dispersion models are therefore essential computational tools for predicting the impacts of emissions from road traffic”

“two urban street canyon models, namely STREET and Operational Street Pollution Model (OSPM), were investigated at Pearse Street, an important traffic route in the centre of Dublin city

“Hourly background concentrations were obtained from an urban air quality monitoring station.. approximately 100 m from the nearest trafficked street. All this recorded parameters were used in computing the modelled CO concentrations. These were then compared with measured CO concentrations”

“An emission factor is the relationship between the amount of pollution produced and the amount of raw material processed or burned. For road traffic, it is the relationship between the amount of pollution produced and the number of vehicle kilometres travelled (grams per kilometre). By using the emission factor of a pollutant and specific data regarding quantities of materials used by a given source, it is possible to compute emissions for the source”

“This paper tries to highlight the STREET model as a suitable screening model for the prediction of CO concentrations in an urban street canyon. When compared with monitored data, concentrations calculated using STREET and OSPM both successfully predict observed variations in air quality”

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Thursday, November 11, 2010

Neuro-fuzzy Urban Air Quality Modelling

Haze over Kuala Lumpur.
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Adaptive neuro-fuzzy modeling for prediction of ambient CO concentration at urban intersections and roadways (10 page pdf, Air Quality, Atmosphere & Health, May 19, 2010)

Modelling of urban air pollution has developed from purely statistical to deterministic but today’s article focuses on neuro-fuzzy techniques which bridges the use of “expert” modelling techniques from artifical intelligence research to estimate extremes as well as average concentrations- in this case, for carbon monoxide at the street/intersection level.

Key Quotes:

“There has been a substantial growth in road traffic over the years and that has resulted in increase in air pollution. In many cities across Europe, USA, Japan, China, and Singapore, vehicular exhaust emissions (VEEs) are now considered as one of the most important sources of urban air pollution”

“screening, assessment, and prediction of ambient air pollutant due to VEE in such urban corridors has become an essential requirement as a part of an efficient local/episodic urban air quality management plan”

“environmental damage is caused both by extreme as well as by the average concentrations of pollutants. Hence, the models should predict not only ‘extreme’ ranges but also the ‘middle’ ranges of pollutant concentrations, i.e., the entire range.”

“Two types of forecast models have been developed. The first model uses a fuzzy expert system and forecasts the possibility of high O3 concentration. The second model uses a neural network system to forecast daily maximum concentration of O3 on the following day”

“The fuzzy models are capable of analyzing linguistic information and efficiently carry out programming/processing with improved knowledge representation and uncertainty reasoning. In addition, the neuro-fuzzy modeling technique can interpret and analyze any kind of information (numeric, linguistic, and logical) and possesses self-learning, self-organizing, and self-tuning capabilities, thus improving the quality of forecasts. The present study was under taken to develop models for CO based on neuro-fuzzy approach for different seasons”


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Wednesday, November 10, 2010

Micro-Environmental Monitoring

A nephelometer installation at Acadia National...
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Monitoring of long-term personal exposure to fine particulate matter (PM2.5) (9 page pdf, Air Quality, Atmosphere & Health, Apr. 23, 2010)

Advances in air quality monitors:  accuracy, portability and allied technologies to locate the observations (GIS and GPS) have progressed to the point where it is possible to continuously monitor personal exposure to air pollution over significant time periods and short time intervals. In today’s review article, the results of such “micro-environmental” monitoring is analyzed with some surprises as to the impact of a few high intensity periods notably in association with wood-burning stoves or a smoking environment indoors or close to traffic outdoors.

Key Quotes:

“A battery-operated, fast-responding nephelometer [(DustTrakTSI model 8520) ]was worn by the individual for a period of 10 months, recording PM2.5 concentration every 5 min..Since no important industrial sources are present in Prague or in its close surroundings, traffic is considered the main source of PM in the urban and suburban region of this city”

“Of the total time monitored, 84.3% was spent indoors, 10.6% outdoors, and 5.1% in transit.”

“both the indoor and outdoor PM2.5 concentrations exhibited high variability and that the averages are affected by extremely high values, again in the indoor and, to a certain extent, also in the outdoor microenvironments.”

“We also recorded high concentrations and high exposures in indoor microenvironments with traditional stoves burning wood and coal. Peak PM2.5 events belong to the highest of all 5-min concentration intervals included in our dataset”

“The overall average of the year-long measurement was 14.9±52.5 µg.m−3 .. The highest PM2.5 average concentration was detected in restaurant microenvironments (294.4 µg.m−3),.The lowest mean aerosol concentrations were detected outdoors in a rural/natural environment (7.0 µg.m−3) and indoors at the monitored person's home (9.3 µg.m−3).”

Advantages of personal monitoring:

  1. "personal samplers are smaller, pollutant specific, more accurate, and able to run for longer time than previously;

  2. sophisticated methods of surveying, such as GPS and GIS, allowing tracking of the movement of the target individual, are well-established and accessible;

  3. an ever-increasing number of specific and sensitive biomarkers can be used together with new methods for their detection and analysis; and

  4. comprehensive databases of human activity are available for use in epidemiological studies”

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Tuesday, November 9, 2010

Bright Green Cities

"We don't know yet how to build a society which is environmentally sustainable, which is shareable with everybody on the planet, which promotes stability and democracy and human rights, and which is achievable in a time frame necessary to make it through the challenges we face. We don't know how to do this yet [but Worldchanging] is a news service for the unimaginable future. What we're out there doing is looking for examples of tools, models and ideas, that if widely adopted would change the game..."

Alex Steffen, the Co-Founder and Executive Editor of Worldchanging

Building a Bright Green Future that Works (17 min TED video)

Life-Cycle Assessment of Nanotechnology and Health

Jay Wright Forrester
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Sustainable Nanotechnology: Through Green Methods and Life-Cycle Thinking (16 page pdf, Sustainability 2010, 2(10), 3323-3338, Oct. 25, 2010)

Before futurist Jay W. Forrester at MIT, developed the “World” model for the Club of Rome in 1970, he focussed on the same Systems Dynamic approach by applying it to an urban setting.  Many years later, we are still learning that a cradle-to-grave approach is needed to build pollution-free sustainable cities, especially with the advent of electronic devices such as TVs and cell phones, whose lifetimes are measured in weeks or months. The result of this and even greater miniaturization is an ever growing mountain of highly toxic materials which form part of either urban waste centres or shipments to even bigger mountains in China, India and other countries, as discussed in this post E-Waste

The article reviewed today assesses the life cycle of nanotechnology with some interesting observations such as the need to identify health impacts as soon as possible in development of these devices.

Key Quotes
“Sustainability and futures studies are linked to each other; the time scales involved may be different from the individual viewpoints of stakeholders, depending on whether they are futurists environmentalists. Futures thinking calls for planning in the time scale of hundreds of years whereas the environmental research community may think in terms of a few decades at the most”

“the need to conduct ―life cycle-based assessments as early in the new product development process as possible, for a better understanding of the potential environmental and human health consequences of nanomaterials over the entire life cycle of a nano-enabled product”

“The wide-ranging applications of nanotechnology have an equally widespread potential to adversely affect human health and the environment, through various exposure routes of nanoparticles, including occupational exposure”

“nano-based products that seem environmentally preferable over other alternatives in the Use stage may not actually turn out to be so when the whole life cycle is considered”

“the effects on human health and the environment are characterized based on environmental loadings… calculated using formulas based upon quantities of pollutants discharged to air, water, and land.”

Risk Assessment goes from quantities of pollutants discharged to analyzing their effects under ambient conditions, through various exposure pathways”

“current Life-Cycle Assessment methodology, developed for use with conventional bulk materials, needs to be reconsidered and modified, if necessary, to make it suitable for evaluating nanomaterials”

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Monday, November 8, 2010

Impact of Pollution from Traffic on Childhood Development

The structure of Ovalene, a polycyclic aromati...
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Prenatal Exposure to Airborne Polycyclic Aromatic Hydrocarbons and Children’s Intelligence at 5 Years of Age in a Prospective Cohort Study in Poland (6 page pdf, Environ Health Perspect 118:1326-1331, 20 April 2010)

Also discussed here: Can Pollution Affect My Child’s IQ? (Health News, Oct. 22, 2010)

Key Quotes:

“study found that children between the ages of eight and 11 living and attending school in areas of Boston with higher levels of traffic pollutants scored an average of 3.7 points lower on IQ tests than children living in less polluted areas”

“The effect of pollution on intelligence was similar to that seen in children whose mothers smoked 10 cigarettes a day while pregnant, or in kids who have been exposed to lead,”

“showed even greater effects on the offspring of expecting mothers living in parts of Harlem and the Bronx in New York City. Researchers found that those children exposed to the highest amounts of PAH pollution had IQs some 4.31 to 4.67 lower than non-exposed kids.”

“This finding is of concern because IQ is an important predictor of future academic performance, and PAHs are widespread in urban environments and throughout the world.”

“Some researchers believe that traffic pollution acts like secondhand smoke or marijuana use, restricting oxygen and nutrients delivered to the fetus,”

“airborne PAH concentrations can be reduced through currently available controls, alternative energy sources and policy interventions,” she says. Indeed, urban planners, regulators and eco-entrepreneurs are experimenting with different methods of reducing smog and other pollutants in problem areas. But until such techniques are perfected and clean-up mandates enforced, those living near busy roadways or otherwise polluted areas put their families at risk every time the front door opens”

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