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Strategies To Promote Green Products | Earth Wise

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Green products are environmentally-friendly products with features that are less harmful to people and the planet.  For instance, green products may require fewer resources to produce, consume less energy, contain non-toxic ingredients, or create fewer emissions.  Some examples include biodegradable waste bags, LED light bulbs, low-flow shower heads, organic cotton clothing, and reusable coffee cups and water bottles.  

But according to new research from two universities in the United Kingdom, companies looking to promote their latest environmentally-friendly product should actually downplay its greenness if they want consumers to buy it.

The study, by researchers from the University of East Anglia and the University of Leeds, found advertising that highlights a product’s green attributes can lead consumers to associate it with weak performance.  The findings, which were recently published in the Journal of Advertising, indicate that companies should downplay a product’s green qualities and instead promote it on more traditional aspects.

An example of these two distinct advertising strategies – green emphasis versus green understatement – can be found in the auto industry.  Car manufacturer Toyota prominently highlights the low emissions and low fuel consumption features of the Prius, employing what the researchers term as ‘explicit signals’.  In contrast, automaker Tesla reduces the prominence of its green attributes, focusing instead on its cars’ acceleration, handling, and other performance-related characteristics.  This is known as the ‘implicit signals’ marketing approach.

After conducting two experiments, the research team found that the implicit, rather than explicit, marketing approach about greenness leads to higher performance evaluations and purchase intent.

Consumers appear more likely to engage in pro-social actions when it’s accompanied by some form of personal benefit. 

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Highlighting product greenness may put consumers off buying

Photo, posted December 21, 2019, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Food Waste And Access To Groceries | Earth Wise

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One-third of all food produced is wasted, which turns out to be a major contributor to carbon emissions.  Most of the carbon emissions associated with food waste are related to the production of the food.  Reducing waste would trickle through the supply chain over time and ultimately less food would be produced.

A study at Cornell’s SC Johnson College of Business looked at a particular strategy for reducing food waste’s environmental impact:  opening more grocery stores.

It turns out that the more stores there are, the lower food waste will be.  Cornell Professor Elena Belavina created a model that incorporates data from the grocery industry, the U.S. Census Bureau, and other academic studies.

When applied to Chicago, which is typical of many American cities, the model predicts that by adding just three or four markets within four-square-mile area, food waste would be reduced by 6 to 9 percent.  This would achieve an emissions reduction comparable to converting more than 20,000 cars from fossil fuels to electric power.  According to the model, not only would food waste be reduced, but so would grocery bills.  By trimming food waste and travel costs, consumers would spend up to 4% less.

Most big cities are well below their ideal density of grocery stores that would minimize food waste. When consumers can purchase perishable goods nearby, they shop more often but buy less each time.  There is less food sitting at home, so there is a much lower likelihood that food will spoil.

New York City, which has an abundance of produce stands and neighborhood markets, comes close to having the ideal density of markets.  Basically, the way to reduce food waste is to bring less groceries home.

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Better access to groceries could reduce food waste, emissions

Photo, posted March 22, 2009, courtesy of Nick Saltmarsh via 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.

The Value Of Abandoned Agricultural Lands | Earth Wise

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It is perhaps surprising to learn that more land is now being abandoned by farming than converted to it. In fact, abandonment of rural lands has become one of the most dramatic planet-wide changes of the modern era, affecting millions of square miles of land.

In part, it is due to rural flight driven by the economic, social, and educational appeal of cities.  It is also a result of climate change and the globalization of the food supply chain.  The global footprint of agriculture has been decreasing over the past twenty years but the global food supply isn’t shrinking.  The lost land has generally been marginal and farming elsewhere has become more productive.

Many researchers see abandoned agricultural lands as a huge opportunity for ecological restoration and strengthening of biodiversity.   Others see these lands as an opportunity for a massive program to plant trees to reduce carbon dioxide in the atmosphere.  A recent study published in Science estimated that planting trees on abandoned agricultural lands could remove 25% of the carbon dioxide humans have added to the atmosphere.

There are strong criticisms to all of these ideas.  In most cases, the studies don’t incorporate the social context of why these lands are in transition, the potential effects on local populations, whether the lands are publicly or privately owned, and whether lands now suitable for regeneration will remain so as climate change advances.

Current government initiatives on degraded lands typically lack even rudimentary planning.  There are real opportunities presented by the vast amounts of abandoned agricultural lands, but there are many caveats and many issues to confront.  As a society, we have barely begun to even think about what to do.

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Could Abandoned Agricultural Lands Help Save the Planet?

Photo, posted May 9, 2010. courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Extreme Heat From Solar Power | Earth Wise

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Renewable sources are playing a growing role in meeting our energy needs, but one place where they have continued to fall short is in industrial processes that require extreme heat.  These include the cement, steel, and glass industries, among others.  These industries account for a significant amount of CO2 emissions because the most effective way to reach the necessary temperatures continues to be combustion of fossil fuels.  The cement industry alone accounts for 7% of global emissions and the need for cement continues to grow.

A previously stealthy startup company backed by Bill Gates and fellow billionaire Soon-Shiong has made a breakthrough in the area of using solar energy to achieve high temperatures.  The company, called Heliogen, has created a solar oven that is capable of generating heat above 1800 degrees Fahrenheit, which is enough for high-temperature industrial processes.

The Heliogen technology uses concentrated solar power to generate heat.  Concentrated solar power uses arrays of mirrors to reflect sunlight and focus it to a single point.  That technology is not new;  there are systems that use it to produce electricity and, to some extent, heat for industry.  But it could not achieve high enough temperatures for producing cement or steel.

The new system uses computer vision software, automatic edge detection and other sophisticated technologies to focus the sun’s rays far more finely than ever before and thereby generate far higher temperatures at the focal point.

Heliogen is now focused on demonstrating how the technology can be used in a large-scale application, such as cement-making.  The selling points to industry are that not only will there be no emissions generated, but that the fuel needed to obtain their extreme heat will be free.

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Secretive energy startup backed by Bill Gates achieves solar breakthrough

Photo courtesy of Heliogen.

Earth Wise is a production of WAMC Northeast Public Radio.

Another Greenhouse Gas Record

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According to the World Meteorological Organization, levels of heat-trapping greenhouse gases in the atmosphere have reached yet another new record high.  Globally averaged concentrations of carbon dioxide reached 407.8 parts per million in 2018, up from 405.5 parts per million in 2017.

The increase year-over-year was similar to that from 2016 to 2017, and remains a little over the average for the last decade.  Global CO2 levels crossed the 400 parts per million threshold in 2015.

Concentrations of methane and nitrous oxide also increased by higher amounts than the average for the past decade, based on observations from the Global Atmosphere Watch network with stations all over the globe.

Since 1990, there has been a 43% increase in total radiative forcing – which is the warming effect on the climate from long-lived greenhouse gases. Carbon dioxide accounts for about 80% of this.  The report notes that the last time the Earth experienced this high a level of CO2 was 3 to 5 million years ago. At that time, global temperatures were 2 to 3 Celsius degrees higher and sea levels were 30 to 60 feet higher than now.

The report includes data on the isotopic analysis of the CO2 in the atmosphere.  CO2 produced by fossil fuel combustion comes from plant material from millions of years ago and does not contain radiocarbon, that is, carbon-14.  CO2 from natural sources contains radiocarbon produced by cosmic rays.  The increasing CO2 levels in the atmosphere contain decreasing levels of radiocarbon, indicating that the overall increase is largely due to human activities.

Overall, global efforts to date to reduce emissions have not been very successful, and this is borne out by the growing levels of carbon dioxide in the atmosphere.

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Greenhouse gas concentrations in atmosphere reach yet another high

Photo courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Carbon Capture As Big Business

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Removing greenhouse gasses from the atmosphere is an essential part of the overall effort to achieve zero net carbon emissions and stabilize the climate.  Since we have not been able to reduce emissions fast enough to do the job, it is important to find ways to pull carbon dioxide out of the atmosphere.

There are many ways to do it, but they tend to be rather expensive and, so far, the need to mitigate climate change does not seem to provide sufficient incentive. A new study by researchers at UCLA, the University of Oxford, and five other institutions, analyzed the possibility of creating a large global industry based on capturing carbon dioxide and turning it into commercial products.

The study investigated the potential future scale and cost of 10 different ways to use carbon dioxide, including in fuels and chemicals, plastics, building materials, soil management, and forestry.  The study looked at processes using carbon dioxide captured from waste products that are produced by burning fossil fuels as well as by simply capturing it directly from the atmosphere.  The study also looked at processes that use carbon dioxide captured biologically by photosynthesis.

The conclusions of the study were that on average each of the ten utilization pathways could use about half a billion tons of carbon dioxide that would otherwise escape into the atmosphere.  Thus, theoretically, these various pathways could take more than five billion tons of CO2 out of the atmosphere.   Currently, fossil fuel combustion emits about 40 billion tons of carbon dioxide.

The authors of the study stress that there is no silver bullet in the fight against climate change.  It will require multiple approaches – including CO2 removal for industrial use – to make real progress

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Carbon dioxide capture and use could become big business

Photo, posted September 18, 2015, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Detecting Methane

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Natural gas has become a huge industry in the United States, increasingly replacing coal in power plants, and otherwise contributing to energy independence.  Unfortunately, it also contributes to climate change.  Methane – the primary component of natural gas – is a powerful greenhouse gas that is estimated to be responsible for as much as a quarter of atmospheric warming.

Not all of the emissions from natural gas come from its use.  In the United States, so-called fugitive emissions from the oil and gas industry total an estimated 13 million metric tons per year.  These emissions basically consist of leakage of various types from the extraction, transportation, and processing of natural gas and cost the industry $2 billion in lost revenue each year.  Globally, that figure is estimated to be $30 billion.

Research labs and startup companies are working on developing and deploying novel technologies to address the growing issue of methane leaks across the fossil fuel supply chain.

One company called LongPath Technologies – a spinout from the University of Colorado – uses frequency comb laser technology that can pinpoint a leak to about a 50 square-foot area from half a mile away.  Other companies use different variations on laser absorption technology to be able to measure methane concentrations from a distance. 

Methane is a much more powerful greenhouse gas than carbon dioxide, but it stays in the atmosphere for much less time.  As a result, reducing methane emissions can pay off much more quickly than reducing carbon dioxide emissions.

The current EPA is trying to eliminate emissions regulations on the natural gas industry, but it is in the industry’s economic interest to curb those emissions even if they were unconcerned about the environment.

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Methane Detectives: Can a Wave of New Technology Slash Natural Gas Leaks?

Photo, posted October 22, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

SUVs And Carbon Emissions

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Global carbon dioxide emissions increased between 2010 and 2018.  The largest contributor to this increase was the power sector as electricity demand around the world continued to grow.   The second largest contributor to increased emission turns out to be SUVs, even while emissions for other cars actually decreased.

During that time period, SUVs more than doubled their global market share from 17% to 39% and their annual emissions rose to more than 700 million tons of CO2, which is more than the yearly total emission of the UK and the Netherlands combined.

This dramatic shift toward bigger, heavier SUVs has offset both efficiency improvements in small cars and savings from electric vehicles.  If SUV drivers were a nation, they would rank 7th in the world for carbon emissions.

SUVs are bigger, they are heavier, and their aerodynamics are poor.  As a result, it takes more gas to drive them.  They started to become popular in the 1980s – mostly in American suburbia – but now they have become globally popular.

The demand for SUVs is thought to be driven by perceptions of heightened safety or increased social status.  There is also the marketing and business strategy of manufacturers who obtain larger profit margins in the SUV segment.  Of course, for at least some consumers, the utility aspects of sport utility vehicles are actually important and not just the status.

For whatever reasons, SUVs are likely to be extremely popular for the foreseeable future as demand for sedans continues to decline.  Fortunately, electric SUVs are beginning to enter the market – including next year’s mass-market priced Tesla Model Y.  Such cars are the best solution to emissions from SUVs.

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Demand for SUVs a Major Contributor to the Increase in Global CO2 Emissions

Photo, posted May 9, 2017, courtesy of Yonkers Honda via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Arctic As A Carbon Source

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According to a new NASA-funded study, the Arctic may now be a source for carbon in the atmosphere rather than being the sink for it that is has been for tens of thousands of years.

The study, published in Nature Climate Change, warns that carbon dioxide loss from the world’s permafrost regions could increase by more than 40% over the next century if human-caused greenhouse gas emissions continue at their current pace.  Worse yet, carbon emitted from thawing permafrost has not even been included in most climate models.

Permafrost is the carbon-rich frozen soil and organic matter that covers nearly a quarter of Northern Hemisphere land area, mostly in Alaska, Canada, Siberia, and Greenland.  Permafrost holds more carbon than has ever been released by humans from fossil fuel burning, but it has been safely locked away by ice for tens of thousands of years.

As global temperatures rise, the permafrost is starting to thaw and release greenhouse gases into the atmosphere.

The recent findings indicate that the loss of carbon dioxide during the winter in the Arctic may already be offsetting carbon uptake during the growing season.  The researchers compiled on-the-ground observations of carbon dioxide emissions across many sites and combined these with remote sensing data and modeling.  They estimate that the permafrost region is now losing 1.7 billion metric tons of carbon during the winter season but taking up only 1 billion during the growing season.

The major concern is that as the Arctic continues to warm, more carbon will be released into the atmosphere from the permafrost region, which will further the warming.  Climate modeling teams across the globe are trying to incorporate these findings into their projections.

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Arctic Shifts to a Carbon Source due to Winter Soil Emissions

Photo, posted July 27, 2015, courtesy of Gary Bembridge via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A New Way To Remove CO2 From The Air

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Researchers at MIT have developed a new way of removing carbon dioxide from a stream of air that could be a powerful tool in the battle against climate change.  The new system can pull carbon dioxide out of almost any concentration level of the gas, even including the roughly 400 parts per million level currently found in the atmosphere.

The technique is described in a new paper in the journal Energy and Environmental Science and is based on passing air through a stack of electrochemical plates. The device is essentially a large battery that absorbs carbon dioxide from the air passing over its electrodes as it is being charged up, and then releases the gas as it is being discharged.

To use it, the device would simply alternate between charging and discharging.  Fresh air or some other feed gas would be blown through the system during the charging cycle and then pure, concentrated carbon dioxide would be blown out during discharging.

The specialized battery uses electrodes coated with a compound called polyanthraquinone, which is composited with carbon nanotubes.  These unique electrodes have a binary affinity to carbon dioxide, which means that they either strongly want to capture carbon dioxide or not at all, depending upon whether the device is charging or discharging.

Carbon dioxide is important in many industries such as soft drinks and greenhouse agriculture.  With this device, the stuff could literally be pulled out of the air.  And, of course, in power plants where exhaust gas is dumped into the air, these novel electrochemical cells could be used to prevent the emission of CO2 into the atmosphere.  At the right price, this could be a game changer.

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MIT engineers develop a new way to remove carbon dioxide from air

Photo, posted August 9, 2007, courtesy of William Clifford via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Potential For Offshore Wind

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According to a new report from the International Energy Agency, offshore wind technology has vast potential for meeting our energy needs.  In total, offshore wind has the potential to generate more than 420,000 terawatt-hours of electricity each year, which is more than 18 times the global electricity demand that exists today.

Based on current policy targets and plummeting technology costs, offshore wind could increase 15-fold by 2040, becoming a $1 trillion industry and eliminating 5 to 7 billion tons of carbon dioxide emissions annually.

Offshore wind today generates just 0.3% of the world’s electricity, but its’ use is growing rapidly.  The industry has grown nearly 30% a year since 2010, and 150 new offshore projects are currently in development around the world.  The leading countries are in Europe – especially in the UK, Germany, and Denmark – but China is greatly expanding its offshore capacity and the US, India, Korea, Japan, and Canada are also expected to make large investments in offshore wind going forward.

Offshore wind is in a category of its own because it is considered a variable baseload power generation technology.  This is because the hourly variability of offshore wind is much lower than solar power or onshore wind.  Offshore wind typically fluctuates far less from hour-to-hour than the other variable energy sources.

Technology improvements and industry growth are driving steep cost reductions for offshore wind.  The cost of offshore wind is expected to be cut in half in the next five years, dropping to $60 per megawatt-hour, which is on par with solar and onshore wind and cheaper than new natural gas-fired capacity in Europe.

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Offshore Wind Has the Potential to Fulfill Global Electricity Demand 18 Times Over

Photo, posted August 9, 2016, courtesy of Lars Plougmann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Emissions From Natural Gas Processing

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Qatar, a small country in the Middle East with a population of about 2.5 million has the highest per capita income of any country in the world.  This is largely a result of being one of the world’s top producers of natural gas.  The upshot of that is that the tiny country has the dubious honor of being the world’s leading emitter of CO2 per capita.

Texas A&M University has a campus in Qatar and researchers there in collaboration with colleagues at the main campus in College Station, Texas have developed a new reactor technology that can help Qatar process its wealth of natural gas while reducing the country’s carbon footprint.

The technology processes natural gas and captured CO2 to produce both syngas – which is a valuable precursor for many products – and high-quality carbon nanotubes, all without releasing CO2 into the atmosphere.

Natural gas reforming is a process by which syngas – a feedstock for liquid hydrocarbons and ultraclean fuels- is produced.  The process requires lots of heat and emits CO2.  The new technology adds a novel CARGEN (or CARbon GENerator) reactor that advances the natural gas reforming process and includes a catalyst that captures the CO2 emissions and produces nanotubes.  The reactor can be driven by either electric or solar power, eliminating the need to burn fuel that ordinarily results in more carbon emissions.

The result is that Qatar’s CO2 emissions would be converted into two products that are important to its economy.  In particular, carbon nanotubes are very expensive and extremely versatile, and can be used to manufacture products such as computers and other high-quality materials.

The next step for the researchers is to partner with industry collaborators to further scale up the technology.

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Qatar Researchers Develop Natural Gas Processing Technology That Could Reduce Qatar’s Carbon Footprint

Photo, posted September 30, 2012, courtesy of Jimmy Baikovicius via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Stranded Coal Assets In Japan

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Japan is facing a looming financial problem as a result of heavy investments in coal technology that may quickly become stranded assets as renewable energy sources become increasingly inexpensive.

Japan is gradually adding more ambitious policies with regard to climate change including goals to reduce emissions and to have renewables become the main source of power over the next three decades.  But despite these policy efforts, Japan is still investing heavily in coal power.  Japan currently has 21 new coal projects with over 11 GW of under-construction, permitted or pre-permitted coal capacity.  But these tens of billions of dollars in assets would have to be closed prematurely in order to remain consistent with the goals of the Paris Climate Agreement.

According to a new report by the Carbon Tracker Initiative, a financial think tank, and the University of Tokyo, offshore wind power will be cheaper than coal in Japan by 2022, new solar cheaper by 2023, and onshore wind less expensive by 2025.  The price of offshore wind is already comparable to existing coal power in Japan.  Japan had a total of 55.5 GW of solar capacity last year and has the potential to reach 150 GW by 2030.

The report notes that 42% of the global coal fleet likely became unprofitable last year and this could rise to 72% by 2040.  The authors contend that building coal power today equals high-cost power and financial liabilities tomorrow.  The planned and operating coal capacity in Japan is partially protected by regulations that give coal generators an unfair advantage in the marketplace.  Ultimately, the stranded coal assets are likely to be passed down to consumers through higher power prices.

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Land of the Rising Sun and Offshore Wind

Photo, posted April 25, 2019, courtesy of Jen via 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.

Urban Agriculture And Sustainability Goals

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In 2016, the City Council of Phoenix, Arizona adopted eight Environmental Sustainability goals for 2050 that lay out the desired long term requirements in order to become a Sustainable Desert City.  Recently, a group of researchers from Arizona State University assessed how urban agriculture can help Phoenix, a desert city of 1.6 million people, meet those sustainability goals.  

Using public records and high-resolution satellite imagery, researchers analyzed the potential benefits of growing crops in three types of urban areas in Phoenix: vacant lots, rooftops, and building facades.  The study, which was supported by the National Science Foundation and the USDA, estimated that there are 28 square miles (or 5.4% of city space) available for urban agriculture.  The data-driven analysis found that 71% of the available areas for urban agriculture would come from existing buildings as opposed to vacant lots. 

All this available space for urban agriculture in Phoenix could supply the city with nearly 183,000 tons of fresh produce annually, which would allow for the delivery of fresh fruits and vegetables to all of the city’s existing food deserts. In fact, the city’s own urban-agriculture output could meet 90% of the fresh produce demand that currently exists in Phoenix. 

In addition to producing food, rooftop agriculture could also reduce the energy use in buildings by 3% per building per year, and displace more than 55,000 tons of CO2 annually.  The use of vacant lots could increase the total Phoenix green space by 17%, and reduce the number of areas lacking green space by 60%.   

This study demonstrates the many different ways that urban agriculture can benefit a city. 

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Urban agriculture can push the sustainability

Photo, posted May 10, 2011, courtesy of Stephen Zank 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.

Amazon And Climate Change

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Online shopping giant Amazon has unveiled a Climate Pledge, committing to meet the goals of the Paris climate agreement ten years ahead of schedule, and to be carbon neutral by 2040. This is the company’s most ambitious push yet to reduce its carbon footprint, which currently rivals that of a small country.  In fact, Amazon is responsible for 48.9 million tons of carbon dioxide last year, which is about 85% of what Switzerland typically emits in a year. 

Amazon, which ships more than 10 billion items a year on fossil fuel-intensive planes and trucks, has ordered a fleet of 100,000 electric vans that will start delivering packages to doorsteps in 2021.  The vans will be made by Rivian, a Michigan-based company that Amazon invested in earlier this year. 

Amazon plans to get 100% of its energy from solar and other renewable sources by 2030.  Currently, it gets about 40% of its energy from renewables. 

Amazon is also investing $100 million in nature-based climate solutions and reforestation projects around the world in order to remove carbon from the atmosphere. 

While announcing these initiatives recently at the National Press Club in Washington, D.C., Amazon CEO Jeff Bezos said the company needs to be a leader on the climate change issue:

We want to say look, if a company of Amazon’s complexity, scale, scope, physical infrastructure, delivering 10 billion items can do this, so can you.

After revealing Amazon’s Climate Pledge, Bezos said he would talk with CEOs of other large companies to try to get them to also sign it.  You can find a link to Amazon’s progress on its commitments by visiting this website.

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‘Middle of the herd’ no more: Amazon tackles climate change

Amazon: Committed to a sustainable future (track progress here)

Photo courtesy of Amazon.

Earth Wise is a production of WAMC Northeast Public Radio.

Emissions-Free Cement

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The production of cement – which is the world’s leading construction material – is a major source of greenhouse gas emissions, accounting for about 8% of global man-made emissions. 

Cement production produces carbon dioxide in two ways:  from a key chemical process and from burning fuel to produce the cement.  The process of making “clinker” – the key constituent of cement – emits the largest amount of CO2.  Raw materials, mainly limestone and clay – are fed into huge kilns and heated to over 2,500 degrees Fahrenheit, requiring lots of fossil fuel.  This calcination process splits the material into calcium oxide and CO2.  The so-called clinker is then mixed with gypsum and limestone to produce cement.

A team of researchers at MIT has come up with a new way of manufacturing cement that greatly reduces the carbon emissions.  The new process makes use of an electrolyzer, where a battery is hooked up to two electrodes in water producing oxygen at one electrode and hydrogen at the other.  The oxygen-evolving electrode produces acid and the hydrogen-evolving electrode produces a base.  In the new process, pulverized limestone is dissolved in the acid at one electrode and calcium hydroxide precipitates out as a solid at the other.

High-purity carbon dioxide is released at the acid electrode, but it can be easily captured for further use such as the production of liquid fuels or even in carbonated beverages and dry ice.  The new approach could eliminate the use of fossil fuels in the heating process, substituting electricity generated from renewable sources. 

The process looks to be scalable and represents a possible approach to greatly reducing one of the perhaps lesser known but nevertheless very significant sources of greenhouse gas emissions.

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New approach suggests path to emissions-free cement

Photo, posted March 26, 2014, courtesy of Michael Coghlan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Other Ways To Cut Vehicle Emissions

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It is pretty clear that the way to drastically reduce vehicle greenhouse gas emissions is to switch as many vehicles as possible to electric power.  As a result, more and more localities are putting in place policies that encourage electrification.

While there is no doubt that electrification is the long-term solution to vehicle emissions, a recent study by MIT and the Ford Motor Company found that, in the short term, there are some places in the US where electric cars are not the best way to reduce emissions.

The study looked at a variety of factors that affect the relative performance of vehicles.  These include the role of low temperatures in reducing battery performance, regional differences in the average number of miles driven annually, and significant differences in the way electricity is generated in different parts of the US.

The results showed that electric vehicles definitely provide the greatest impact in reducing greenhouse gas emissions for most of the country – and particularly on both coasts and in the south – but that there are some places in the upper Midwest where the greatest reduction would be achieved by the use of lightweight gasoline-powered vehicles.

In places like parts of Wisconsin and Michigan, it is mostly rural, there are cold winters, and electricity is predominantly generated by coal-powered plants.  In these places, if gas-powered lightweight cars were to be used, the overall benefit would be greater than that of electric cars.  Unfortunately, there are no high-volume lightweight gasoline-powered mid-sized cars on the market in the US.  Ironically, the only cars of that class using lightweight aluminum construction are Teslas.

While electric cars are truly the long-term solution, the study does demonstrate the benefits of reducing the weight of vehicles.

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Photo, posted February 9, 2018, courtesy of Dave Field via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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