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Increasing Air Pollution | Earth Wise

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According to researchers from the University of Exeter, half of the world’s population is exposed to increasing air pollution despite global efforts to improve air quality.  The study, which was completed in conjunction with the World Health Organization, suggests that air pollution represents a major and growing threat to human health. 

For the study, which was recently published in the journal Climate and Atmospheric Science, the researchers reviewed global air quality trends between 2010 and 2016.  The research team examined those findings against a backdrop of global policies to reduce air pollution.  The researchers used ground monitoring data and satellite data to develop yearly air quality profiles for individual countries and regions. 

The scientists focused on fine particulate matter, which is a mixture of solid particles and liquid droplets found in the air.  Some of the particles, like dust, soot, or smoke, are large enough to be seen by the naked eye.  Others are so small that they can only be seen using a microscope.  Inhaling fine particulate matter can cause all sorts of health issues, including asthma, respiratory inflammation, and even promote cancer. 

For much of the world’s population, the consequences of polluted air are more deadly than war, violence, and many diseases.  According to the World Health Organization, more than four million deaths every year can be attributed to outdoor air pollution.  Some of the major sources of air pollution include coal-fired power plants, agriculture, transportation, and deforestation. 

The study found that low and middle income countries experience the highest burden of air pollution around the world, with the largest concentrations found in central and southeastern Asia.

More long term policies are needed to curb this growing threat to public health. 

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Half of the world’s population exposed to increasing air pollution

Photo, posted August 2, 2019, courtesy of Ron Reiring via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Side Effects Of Geoengineering | Earth Wise

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As the world struggles to reduce the greenhouse gas emissions that are warming the global climate, some researchers are exploring proposals to deliberately engineer climate changes to counteract the warming trend.  One of the most widely discussed approaches is to shade the Earth from a portion of the sun’s heat by injecting the stratosphere with reflective aerosol particles.  Proponents of this idea point out that volcanoes do essentially the same thing, although generally for only a limited amount of time.  Particularly large eruptions, such as the Krakatowa eruption of 1883, wreaked havoc with weather around the world for an entire year.

Schemes to launch reflective aerosols – using planes, balloons, and even blimps – appear to be quite feasible from the standpoint of physically accomplishing them. But this says nothing about the political, ethical, and societal issues involved.  The point is that such an approach could indeed lower global temperatures and thereby potentially offset the warming effects of greenhouse gases.

A study by scientists at MIT looked at what other effects such a solar geoengineering project might have on the climate.  Their modeling concluded that it would significantly change storm tracks in the middle and high latitudes.  These tracks give rise to cyclones, hurricanes, and many more ordinary weather phenomena.

According to the study, the northern hemisphere would have weakened storm tracks, leading to less powerful winter storms, but also stagnant conditions in summer and less wind to clear away air pollution.  In the southern hemisphere, there would be more powerful storm tracks.

Aside from turning the world’s weather patterns inside out, solar geoengineering would do nothing to address the serious issue of ocean acidification caused by increasing carbon dioxide levels.

As many have pointed out, playing the geoengineering game would have many unintended consequences.

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Study: Reflecting sunlight to cool the planet will cause other global changes

Photo courtesy of MIT.

Earth Wise is a production of WAMC Northeast Public Radio.

The Lockdown Cleans Up Indian Air | Earth Wise

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Our stories often discuss how human activities change the natural environment.  With most of us confined to our homes, the lack of human activities is having profound effects on the environment.  We are talking about some of these this week.

India suffers from some of the worst air pollution in the world.  Of the most polluted cities in the world, 21 out of 30 were in India in 2019.  According to World Health Organization standards, at least 140 million people in India breathe air containing 10 times or more greater levels than the safe limit for pollutants.  Air pollution contributes to the premature death of 2 million Indians every year.

Half of India’s air pollution comes from industry, 27% from vehicles, and 17% from crop burning.  Crop burning is prevalent because it is much cheaper than mechanical tilling after the harvest.

On March 25, the Indian government placed its 1.3 billion citizens under a strict lockdown to reduce the spread of COVID-19.   The country-wide mandate decreased activity at factories and drastically reduced car, bus, truck, and airplane traffic.

Within one week, NASA satellite sensor observed aerosol levels at a 20-year low for this time of year in northern India.  Aerosols are tiny solid and liquid particles suspended in the air that reduce visibility and can damage the human lungs and heart.  Some aerosols have natural sources, such as dust storms, volcanic eruptions, and forest fires.  But many come from human activities such as the burning of fossil fuels and croplands.  Scientists expected to see changes in atmospheric conditions during the Indian lockdown, but the current changes are dramatic.  They also present a unique opportunity to separate how natural and human sources of aerosols affect the atmosphere.

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Airborne Particle Levels Plummet in Northern India

Photo, posted April 29, 2020, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Coronavirus Shutdowns And The Environment | Earth Wise

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Our stories often discuss how human activities change the natural environment.  With most of us confined to our homes, the lack of human activities is having profound effects on the environment.  We are talking about some of these this week.

The COVID-19 pandemic is a global catastrophe, but it has ironically been a boon for the environment.  By taking billions of people off the streets around the globe and slashing all forms of travel, the global environment has seen dramatic changes.

Sea turtles in many countries are prospering by not having to compete with humans for precious beach space.  Animals everywhere have more freedom to roam and are taking advantage of the opportunity. The Himalayas are visible from parts of India for the first time in decades.

Satellite imagery has shown dramatic drops in nitrogen dioxide emissions in China, where pollution from vehicles is a serious public health problem.  Similar reductions in air pollution are evident in India, Italy and even in Los Angeles.  The city that is notorious for its smog suddenly has pristine air.

In Venice, water in the canals has become clear in the absence of heavy boat traffic stirring up sediments from the bottom.  Wildlife that normally is invisible such as jellyfish are being spotted.

Not all the changes to animal behavior are desirable.  Some wildlife that have become dependent on humans as a source of food are becoming aggressive and are taking to the streets of cities to look for food.  Monkeys in Thailand are mobbing towns and brawling, hunting for things to eat.  Rats in New York City are fighting over suddenly meager food supplies.

In many ways, the natural world is reacting to much of humanity sheltering in place.

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On Earth Day 2020, coronavirus shutdowns are a gift to the environment

Photo, posted April 2, 2020, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Shutting Down Pollution | Earth Wise

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With much of the country shut down as the coronavirus forces people to stay at home, there has naturally been a drastic reduction of traffic on roads and highways.   And with that decrease, there has been a dramatic reduction in pollution as well.

A satellite that detects emissions in the atmosphere linked to cars and trucks has observed huge declines in pollution in major metropolitan areas such as Los Angeles, Seattle, New York, Chicago, and Atlanta.

Los Angeles is infamous for its rush-hour traffic but that has pretty much ceased to exist. Similar changes can be seen in the San Francisco Bay Area, where nearly 7 million residents have been ordered to shelter in place.  New York City is less dependent on car travel than in other metro areas, but the shutdown of office buildings, schools, and restaurants has nonetheless resulted in a substantial reduction of traffic on the streets of the city.

While this sudden decline in air pollution over U.S. cities has some near-term health benefits, those benefits are likely to be fairly minor in the big picture.  When the coronavirus outbreak subsides and people are allowed to leave their homes and go back to their normal lives, air pollution will most certainly rebound to previous levels.  In any event, studies have shown that long-term exposure to air pollution has a larger impact on public health than any transient events.

Having much cleaner air for a while is certainly a good thing, but this shutdown is not a sustainable way to reduce air pollution and the long-term effects of the coronavirus crisis will certainly not be positive.

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Traffic and Pollution Plummet as U.S. Cities Shut Down for Coronavirus

Photo, posted March 15, 2020, courtesy of Tom Collins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar And Wind Power In China | Earth Wise

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Reducing greenhouse gas emissions is a global challenge and nowhere is that challenge greater than in China.  China accounts for 30% of the world’s emissions and much of that comes from coal power plants.  If the world is going to reach its climate targets, China is going to have to replace as much as possible of its current power mix with renewable energy.

As of 2018, China still made 69% of its electricity from fossil fuels.  Its vast coal reserves have driven its rapid industrialization and better standard of living.  But terrible air pollution problems along with climate issues have led to heavy investments and rapid expansion of both wind and solar power in China.

China is now a world leader in renewable energy, both in terms of producing and using renewable power.  At the start of 2016, China had installed a total of 145,000 megawatts of wind power, which is 3,000 MW more than all 28 European Union countries combined.  And this has occurred even though China only started developing their wind power industry 30 years later than the first EU countries.

Until 2009, China exported almost all the solar panels it produced.  But gradually China began to use solar energy in a big way.  The industry took off in 2014, and growth has been exponential.  Solar power production in China is now almost as extensive as wind power.

One has to consider that much of China’s electricity production is used by industries that produce products for the rest of the world.  In effect, these are exported emissions.  China has a long way to go in replacing its fossil fuel generation and we all have a stake in China succeeding in the task.

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China’s rapid development of solar and wind power

Photo, posted November 12, 2007, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Cost Of Air Pollution | Earth Wise

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The environmental consequences of burning fossil fuels are a dominant topic.  The increasing changes in the climate have far-reaching effects across the globe and are a growing geopolitical crisis.  But the climate effects of fossil fuel emissions are by no means the only problem they cause.  

A new report by the Center for Research on Energy and Clear Air has, for the first time, attempted to quantify the global economic and health impacts of fossil fuel-caused air pollution.  In total, the estimate is that the economic and health costs of air pollution from burning fossil fuels totaled $2.9 trillion in 2018, calculated in the form of work absences, years of life lost, and premature deaths. The cost represents 3.3 percent of global GDP, or about $8 billion per day. 

The study focused on the health impacts of three specific types of pollutants:  nitrogen dioxide, ozone, and fine particulate matter, which has the greater impact.  Collectively, these pollutants cause about 1.8 billion days of missed work due to disease and $2.2 trillion in air pollution costs every year. Together, air pollution from these three pollutants is responsible for 4.5 million premature deaths around the world each year.

According to the report, the most premature deaths from fossil fuel-related air pollution in 2018 were in mainland China (1.8 million), India (1 million), and the United States (230,000). As a result, those three countries also faced the highest annual costs: $900 billion in China, $600 billion in the U.S., and $150 billion in India. 

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Toxic Air: The Price of Fossil Fuels (Full Report)

Photo, posted November 17, 2019, courtesy of Kristoffer Trolle via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving Costs And Reducing Emissions From Shipping | Earth Wise

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International shipping is a large and growing source of greenhouse gas emissions.  Maritime transport produces about a billion tons of CO2 annually, accounting for about 2.5% of global greenhouse gas emissions.  The environmental impact of shipping includes air pollution, water pollution, and even acoustic pollution.  In many coastal areas, ships are responsible for more than 18% of some air pollutants.  Overall, there are more than 100,000 transport ships at sea, of which about 6,000 are large container ships.

In recent years, the shipping sector has had both internal willingness and external pressure to reduce emissions, but shipping is a tough, competitive business and it isn’t easy to stay competitive and help protect the environment.

A recent study at Abo Akademi University in Finland has found that improved ship utilization rates and investments in environmentally sustainable technologies for enhanced energy efficiency would significantly reduce carbon dioxide emissions.  Of equal importance, those same measures would contribute to lowering of freight costs.

If the same cargo volume can be shipped using less fuel, shipping companies will gain major savings in terms of fuel costs.  Digitalization can provide valuable benefits.  For example, new digital planning and booking systems would enable smarter use of routes while also diminishing traffic with half-empty vessels or even ones with no cargo aboard.  Reducing such underutilization would improve the capacity utilization rate and eliminate emissions caused by so-called ballast traffic.

Global shipping continues to grow.  It is essential that it becomes smarter and more efficient to protect the environment and improve its economics.

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Environmentally friendly shipping helps to reduce freight costs

Photo, posted February 18, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Air Pollution And Bone Health | Earth Wise

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Many of the negative effects of air pollution are well documented.  Studies have shown that exposure to air pollution is associated with an increased risk of lung cancer, stroke, respiratory and cardiovascular diseases, and so on. 

Now, according to a new study in India led by the Barcelona Institute for Global Health (ISGlobal), exposure to air pollution is also associated with a higher risk of developing osteoporosis.  Osteoporosis, which literally means porous bone, is a disease in which the density and quality of bone is reduced. As bones become more porous and fragile, the risk of fracture is greatly increased. 

The study, which surveyed 3,700 people from 28 villages in southern India, was recently published in the medical journal Jama Network Open.     

The researchers used a model to estimate air pollution by fine particulate matter (commonly referred to as PM2.5) and black carbon at each participant’s residence.  The research team then assessed bone health using a special type of radiography (called dual-energy x-ray absorptiometry) that measures bone density.  They measured bone mass of the participants’ left hip and at the lumbar spine.

The results showed that exposure to air pollution, particularly fine particulate matter, was associated with lower levels of bone mass.  Annual average exposure to PM2.5 was 32.8 micrograms per cubic meter, well above the maximum levels recommended by the World Health Organization (10 micrograms per cubic meter) and the U.S. EPA (12 micrograms per cubic meter).   

The researchers say their findings add to a growing body of evidence that indicates that particulate air pollution is relevant for bone health. 

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Air pollution can worsen bone health

Photo, posted November 15, 2019, courtesy of Ninara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Air Pollution With Plants | Earth Wise

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New research by Ohio State University suggests that adding plants and trees to the landscapes near factories and other pollution sources could reduce air pollution by an average of 27%.  In addition, the study indicates that, in many cases, plants may be a cheaper option for cleaning the air than more technological approaches.

The study looked at public data on air pollution and vegetation on a county-by-county basis across the lower 48 states. It then calculated what adding additional trees and plants might cost.  The calculations included the capacity of current vegetation to mitigate air pollution as well as the effects that restorative planting might have on pollution levels.

In 75% of the counties analyzed, it was cheaper to use plants to mitigate air pollution rather than add technological interventions such as smokestack scrubbers to the sources of pollution.  The results varied according to the pollution source.  For example, technology is cheaper at cleaning the air near industrial boilers than ecosystem approaches.  For the broad manufacturing industry, one approach or the other was favorable, depending on the type of factory.

Adding trees or other plants generally can lower air pollution levels in both urban and rural areas, although success rates depend on a variety of factors including how much land is available to grow new plants and current air quality.

Reducing air pollution is critical to public health.  An estimated 4 in 10 people in the U.S. live in areas with poor air quality, leading to health issues including asthma, lung cancer, and heart disease.  The study shows that nature should be part of the planning process for industry to deal with air pollution.

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Nature might be better than tech at reducing air pollution

Photo courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Roofs Going Green

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Green roofs are roofs on buildings that are partially or completely covered with vegetation and a growing medium, generally planted over a waterproofing membrane.  The modern version of these roofs began in Germany in the 1960s and spread to many other European countries over time.  With concerns about climate change and shrinking natural resources rising, green roofs are becoming increasingly popular across North America.  The Toronto-based organization Green Roofs for Healthy Cities estimates that the number in North America has increased by about 15% since 2013.

Replacing black asphalt and shingles with plants can lower the surrounding air temperature, filter dirty storm water, and reduce building energy use.  The National Research Council of Canada estimates that a green roof can reduce air conditioning use in a building by as much as 75%.  The roofs also help to reduce air pollution and greenhouse gas emissions according to the EPA.

As the benefits of green roofs become more widely known, cities around the world are passing green roof legislation.  Copenhagen passed a law in 2010 requiring all new commercial buildings to have green roofs if their roofs are not sloped too much.  Toronto was the first city in North America to pass a green roof law in 2009.  Over 640 green roofs covering more than five million square feet have since been constructed in Toronto.

Apart from the environmental benefits, green roofs are providing pleasant spaces in the urban environment that may include flower beds, trees, herb gardens, gazebos and picnic tables.  As for the economics, studies show that over the course of a roof’s lifetime, green roofs are actually considerably cheaper than conventional roofs taking into account energy savings.

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The Green Revolution Spreading Across Our Rooftops

Photo, posted July 15, 2014, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Air Quality In The U.S.

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Globally, poor air is a serious problem.  According to the World Health Organization, exposure to air pollution is linked to the premature deaths of an estimated 7 million people every year.  In fact, 91% of the people on the planet live in places where air pollution exceeds WHO guideline limits. 

In the United States, air pollution has dramatically improved over the last four decades due in large part to federal regulations put in place under the Clean Air Act of 1970.  Fine particulate matter (known as PM2.5) and other pollution, including ozone, sulphur dioxide, and nitrogen dioxide, have all decreased during this time span. 

But according to recent research, this trend has unfortunately done an about-face.  New data reveals that air pollution has increased nationally since 2016.  An analysis of Environmental Protection Agency data by researchers at Carnegie Mellon University found that, on average, fine particulate pollution increased 5.5% across the country between 2016 and 2018. 

This increase in fine particulate pollution was associated with nearly 10,000 additional premature deaths in the United States during that time period. 

According to researchers, there are several factors likely causing this uptick in unhealthy air, including increases in both driving and the burning of natural gas.  Wildfires out west are also thought to be a major contributor. 

The researchers also suggest that a decrease in enforcement of the Clean Air Act may also be playing a role.  The law put in place strict air pollution standards for vehicles, factories, power plants, and other sources, and is credited with saving hundreds of thousands of lives.

It’s time for clean air to be recognized as a basic human right.

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America’s Air Quality Worsens, Ending Years of Gains, Study Says

Photo, posted April 6, 2007, courtesy of Brett Weinstein via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Benefits Of Zero-Carbon Cities

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A new report issued by a coalition of 50 leading international institutions shows that low carbon initiatives in cities could reduce urban emissions by nearly 90% and support 87 million jobs worldwide by 2030.  The report finds that implementing low carbon measures in cities would be worth almost $24 trillion by 2050.

Cities are home to more than half the world’s population but produce 80% of gross domestic product and 75% of carbon emissions.  The research highlights the significant benefits carbon reduction can bring to cities in areas such as public health, job creation, and poverty alleviation.

The report shows that it is possible to cut 90% of emissions from cities using currently available technologies and practices including carbon savings from buildings, transportation, materials efficiency, and waste reduction.  Doing so would require an investment of nearly $2 trillion per year but would generate annual returns of nearly $3 trillion in 2030 and $7 trillion in 2050 based on cost savings alone.  Many low carbon measures would pay for themselves in less than five years, including more efficient lighting, electric vehicles, improved freight logistics, and solid waste management.

In addition to economic benefits, compact, connected and clean cities could provide a higher standard of living and greater opportunity for all.  These measures would also reduce air pollution, cut chronic traffic congestion, and improve worker productivity.

The report offers case studies from around the world where national and local governments have worked together to rapidly and profoundly transform their cities for the better within 20 or 30 years.

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The benefits of investing in zero-carbon cities

Photo, posted September 8, 2018, courtesy of Steffen Flor via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Electric Buses In Latin America

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Latin America has become increasingly urbanized.  In fact, about 80% of the region’s population lives in cities today and by 2050, that figure could climb to 90%.  Transportation is the largest and fastest-growing source of energy-related emissions in Latin America and accounts for about a third of all of the region’s carbon dioxide emissions. 

Private vehicle ownership is rising in Latin America but at the same time, the region’s rapidly growing cities have increased demand for buses, taxis, and motorcycles.  Currently, an estimated 64,000 people die prematurely every year in Latin America and the Caribbean as a result of air pollution, which is mostly caused by transportation emissions.

Given this situation, major cities across Latin America – from Colombia to Argentina – are starting to adopt electric bus fleets.   Latin America actually has the highest use of buses per person globally.  So, the transition to electric buses is an important step toward meeting climate targets, cutting fuel costs, and improving air quality.

Medellin, Colombia – whose metropolitan area has 3.7 million people – has started to add electric buses to its fleet, the rest of which runs on natural gas.  When new units arrive from China later this year, Medellin will have the second largest electric bus fleet in Latin America, after Santiago, Chile. 

Worldwide, 425,000 electric buses are in operation, 99% in China.  Europe has a couple of thousand while the United States has only 300.  But going forward, and especially in Latin America, electric buses are the wave of the future.  Estimates are that there will be 1.3 million on the roads by 2040.

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An Increasingly Urbanized Latin America Turns to Electric Buses

Photo, posted April 22, 2018, courtesy of Hans Johnson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Cleaner Air Saves Lives

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A new study by Columbia University has concluded that lower air pollution levels saved an estimated 5,660 lives in New York State in 2012, compared to 2002 mortality levels.

The study looked at New York State levels of the specific type of pollution known as fine particulate matter, referred to as PM2.5.  These microscopic particulates are a mixture of solid particles and liquid droplets that either come from burning fuel or are formed in the atmosphere as a result of complex reactions of chemicals such as sulfur dioxide and nitrogen oxides from power plants, industries, and automobiles.

Long-term exposure to PM2.5 can lead to respiratory and cardiovascular problems.

The study looked at extensive amounts of data to analyze trends in PM2.5 levels across New York State.  The data showed that PM2.5 levels dropped by 28 to 37% between 2002 and 2012.  This was a result of continued progress in cleaner vehicles, the reduction of high sulfur-dioxide emitting coal-burning power plants, and other air pollution reduction programs.  They calculated that this amount of reduction in PM2.5 reduced the air pollution mortality burden for New York State residents by 67% – from 8,410 premature deaths in 2002 to 2,750 deaths in 2012.

The study provides evidence that emission controls on air pollutants – which were initiated by the Clean Air Act of 1970 and later expanded in 1990 – have improved public health across New York State.  According to the researchers, the study is a key step to documenting the health benefits from cleaner air.

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Air Pollution Cuts Are Saving Lives in New York State

Photo, posted October 13, 2018, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Indoor Pollution

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We mostly think of air pollution as an outdoor problem.   The primary culprits are vehicle and factory exhaust as well as occasional wildfire smoke.  What we don’t think about is the air quality inside our own homes.

Researchers at Washington State University have found that indoor pollution levels can be surprisingly high and that they vary throughout the day and increase as temperatures rise.

Indoor air pollution comes from a variety of sources, including building materials, furniture, household chemical products, and from activities like cooking.  One of the most serious pollutants is formaldehyde, which often is emitted from gypsum wallboard.  About half of the gypsum used in homes as drywall is made from waste products from the coal industry.  When the material is heated, formaldehyde and possibly even mercury can be emitted.

Pollutant levels rise in homes as temperatures increase.  Thus, the highest levels of pollution occur in the afternoon and the lowest are in the early morning.  Before this research, manufacturers and builders assumed that pollution levels were pretty much constant over time.

Building laws require that homes are structurally sound, and that people are comfortable, but there is little regulation of air quality in people’s homes.  One of the best ways to clear out harmful chemicals is with ventilation to the outdoors.  But with increased concern about reducing energy use, builders are making homes more airtight, which may inadvertently be worsening the problem.

We need to balance making more energy efficient homes with protecting our health by being aware of the dangers that lurk in the air in our homes.  Running the air conditioning or opening windows are good things to do.

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Researchers uncover indoor pollution hazards

Photo, posted October 14, 2010, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change Is Not Natural

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It has been the overwhelming consensus of the scientific community for a long time that human activity and other external factors are responsible for the continuing rise in global temperature.  Despite this widespread agreement, there have been those who argue that natural ocean cycles might be influencing global warming over the course of multiple decades.

A new study, published in the Journal of Climate, provides an answer to the question of how much influence natural cycles might have, and that answer is very little to none.

The study looked at observed ocean and land temperature data since 1850 and, apart from human-induced factors such as greenhouse gas concentrations, took into account other occurrences such as volcanic eruptions, solar activity, and air pollution peaks.  The findings demonstrated that slow-acting ocean cycles do not explain the long-term changes in global temperatures.

Based on the study, the researchers can state with confidence that human factors like greenhouse gas emissions and particulate pollution, along with year-to-year changes caused by natural phenomena like volcanic eruptions or El Niño, are sufficient to explain virtually all the long-term changes in temperature.  The idea that the oceans could have been driving the climate either in a colder or warmer direction for multiple decades in the past and therefore will do so in the future is unlikely to be correct.

A number of previous studies have compared flawed observations with flawed modeling results to claim that naturally-occurring ocean cycles have played a large role in global temperatures.  The new study shows that such cycles have little influence on the climate.  Reducing greenhouse gas emissions is really what we need to do.

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Global temperature change attributable to external factors, confirms new study

Photo, posted November 13, 2007, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Schools And Solar Power

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A new study from Stanford University looked at the benefits of installing solar panels on the rooftops of schools.  According to the study, taking advantage of all the viable space for solar panels could allow schools to meet up to 75% of their electricity needs and reduce the education sector’s carbon footprint by as much as 28%.

Given the long list of spending priorities for schools, solar power seems like a luxury item.  But the Department of Energy estimates that K-12 schools spend more than $6 billion a year on energy and, in many districts, energy costs are second only to salaries.  In the higher education sector, yearly energy costs add up to more than $14 billion.  In total, educational institutions account for approximately 11% of energy consumption by U.S. buildings and 4% of the nation’s carbon emissions.

The Stanford study suggests that investments in the right solar projects combined with the right incentives from states could free up much-needed money in school budgets.

To no surprise, the study finds that three large, sunny states – Texas, California, and Florida – have the greatest potential for generating electricity from solar panels on school rooftops.

Apart from measurable effects on air pollution and electricity bills, solar installations at schools can also provide new learning opportunities for students.  In fact, some schools are already using data from their on-site solar energy systems to teach students basic ideas about fractions, as an example, as well as more sophisticated concepts such how shifting solar panel angles can affect power production.

According to the study, nearly all states could reap value from school solar projects.

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What happens when schools go solar?

Photo, posted February 28, 2011, courtesy of Black Rock Solar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Smog And Solar Power

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China has been struggling with some of the worst air pollution in the world.  Beijing frequently sits under a brown blanket made of exhaust gases from industry, cars and coal fires, which dump harmful particulate matter, soot, sulfur dioxide and nitrogen oxides into the air.

The human health consequences are severe.   According to the World Health Organization,air pollution contributes to about 1.6 million premature deaths in China each year.  World-wide, air pollution is implicated in over 7 million deaths annually.

Faced with this air pollution crisis, China has undertaken a wide variety of measures to improve its air and curb carbon dioxide emissions alongthe way.  Among other things, China has invested heavily in the deployment of solar power and has plans for ever greater expansion of solar power in the future.

A study by researchers at ETH in Zurich looked at the impact of China’s air pollution on the production of solar energy.  The smog in China’s cities reduces the amount of solar radiation that reaches the ground and therefore significantly reduces the power output of solar energy systems. According to the study, solar radiation would increase by an average of 11% nationwide as a result of strict air pollution control measures.  In some places, cleaning up the air would result in 26% more energy production.

China’s electric power industry is the world’s largest electricity producer, having passed the United States in 2011.  Two-thirds of the electricity in China still comes from coal, which, apart from the serious climate and health consequences associated with its use, continues to make it more difficult to switch to clean solar power.  Much work remains to be done.

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Fighting smog supports solar power

Photo, posted February 7, 2014, courtesy of Flickr. 

Earth Wise is a production of WAMC Northeast Public Radio.

Cleaner Air For China

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For more than 15 years, the Chinese government has been grappling with some of the deadliest air pollution in the world.  Extreme pollution events are a regular wintertime occurrence and health experts estimate that more than a million people die each year in China from particulate air pollution.

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