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Electric trains are healthier

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The majority of commuter trains in the U.S. are powered by diesel fuel.  This is despite the fact that electric trains are quieter, more reliable, and produce fewer greenhouse gases than diesel locomotives.  A new study has found that electric trains are healthier for passengers as well.

Caltrain carries millions of passengers a year along a 47-mile route between San Francisco and San Jose.  It is the busiest commuter rail system in the western U.S.  Over a six-week period beginning in August 2024, Caltrain retired all 29 of its diesel locomotives and replaced them with electric trains.

As the process began, an environmental engineering and environmental health professor at UC Berkeley noticed the rapid change in the air aboard the trains and decided to study its potential health impacts.  With the support of Caltrain, he installed black carbon detectors aboard the trains and tracked the improvements in air quality as old diesel locomotives were being replaced by new electric trains.

Statistical analysis of the reduction in black carbon exposure achieved by the change predicted a reduction in excess cancer deaths by 51 per million people for passengers and 330 per million people for train conductors.  EPA policy states that any exposure that increases the average individual’s cancer risk by more than one per million is considered unacceptable.

In the context of the whole U.S. where millions of people commute by rail every day, the study predicts that hundreds of cases of cancer could be prevented each year.  California has long-term plans to electrify most of its rail systems.  The study indicates that the process shouldn’t be carried over the next 25 years but rather be sped up.

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Electric trains are quieter, more reliable than diesel. New study finds they’re healthier, too.

Photo, posted September 4, 2024, courtesy of J. Kehoe via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Removing microplastics from water

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Microplastics come from the breakdown of larger plastics in the environment as well as from direct use in various products such as certain cosmetics.  They are found everywhere, from oceans and mountain peaks to the air and water, and alarmingly, in our bodies.  They are ingested by all sorts of organisms, from tiny plankton to fish and marine mammals.  Microplastics just don’t go away.  They don’t biodegrade so they simply accumulate in the environment.

Researchers at North Carolina State University have recently demonstrated proof of concept for a system that actively removes microplastics from water.  Such a system has the potential for helping to cleanse oceans and other bodies of water from the tiny plastic particles.

The system makes use of soft dendritic colloids, which are tiny particles that have the ability to stick to just about any surface.  These sticky particles can attract microplastics and grab them, even in wet and salty conditions.  The colloids are made from chitosan, a harmless and biodegradable polymer made from processed shellfish waste.

The researchers produced small pellets of the colloids that also contain small amounts of magnesium, which makes them bubble up and rise to the surface of water.  The pellets are coated with a gelatin layer, which blocks the magnesium.  As the gelatin gradually dissolves away, the pellets collect microplastics.  Eventually, the result is a microplastic-laden scum that rises to the surface where it can be skimmed away.

The scum itself can be bioprocessed into more chitosan that can create more of these microcleaner pellets to then capture more microplastics.  The researchers are investigating how the process can be scaled up to become a valuable tool in dealing with the microplastics problem.

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New Water Microcleaners Self-Disperse, Capture Microplastics and Float Up for Removal

Photo, posted January 17, 2018, courtesy of Bo Eide via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Trapping carbon with rocks

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Many experts say that combating global warming will require both drastically reducing the use of fossil fuels and permanently removing billions of tons of CO2 already in the atmosphere.  Developing practical, large-scale technologies for carbon removal is a significant challenge.

There is a nearly inexhaustible supply of minerals that are capable of removing carbon dioxide from the atmosphere, but they don’t do it quickly enough to make a significant dent in the ever-growing supply in the atmosphere.  In nature, silicate minerals react with water and atmospheric CO2 to form minerals in the process called weathering.  But this chemical reaction can take hundreds or even thousands of years.

Researchers at Stanford University have developed a new process for converting slow-weathering silicates into much more reactive minerals that capture and store carbon quickly.  The new approach resembles a centuries-old technique for making cement.  They combine calcium oxide and another common mineral containing magnesium and silicate ions in a furnace.   The result are new materials that, when exposed to water, quickly trap carbon from the atmosphere.

In their experiments, the carbonation process took weeks to months to occur, thousands of times faster than natural weathering.

The idea would be to spread these materials over large land areas to remove CO2 from the air.  Meaningful use for trapping carbon would require annual production of millions of tons.  But the same kiln designs used to make cement could produce the needed materials using abundant minerals found in many places.  In fact, the required minerals are often common leftover materials – or tailings – from mining.

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Scientists discover low-cost way to trap carbon using common rocks

Photo courtesy of Renhour48 via Wikimedia.

Earth Wise is a production of WAMC Northeast Public Radio

Microplastics and birds

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Microplastics are tiny plastic particles, less than 5 millimeters in size, that come from the breakdown of larger plastics, synthetic fibers, microbeads, and tire wear.  Microplastics are found in oceans, rivers, soil, and even the air we breathe. These particles can take hundreds of years to degrade, spreading across ecosystems and accumulating in unexpected places, such as deep-sea sediments and Arctic sea ice.

According to a new study by researchers from the University of Texas at Arlington, microscopic plastic pollutants drifting through the air are lodging in the lungs of birds.  These findings raise  significant concerns about the impact on their respiratory health, but also raise alarms about potential risks to human health.

Birds were chosen for the study because they are found in almost every corner of the world and often share environments with humans. 

In the study, the research team examined 56 different wild birds from 51 distinct species, all sampled from the Tianfu airport in western China.  The researchers found high concentrations of microplastics in bird lungs, with an average of 221 particles per species.  The most common types identified were chlorinated polyethylene, which is used for insulating pipes and wires, and butadiene rubber, which is a synthetic material in tires.

Although there is no established “safe” level of plastic particles in lung tissue, high levels of microplastics have been linked to serious health risks, including heart disease, cancer, respiratory issues, and fertility problems.

The study highlights an urgent need to tackle plastic pollution in the environment because of its far-reaching impact on ecosystems and human health.  

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Birds breathe in dangerous plastics—and so do we

Photo, posted January 28, 2017, courtesy of Pete Richman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Fighting fires with man-made wind

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Researchers at Ohio State University have developed a new portable tool that may help firefighters battle blazes more efficiently and with less risk.

Traditional firefighting methods include chemical foams – which are toxic – and the use of hydrants, which can strain water resources.  The recent fires in Southern California demonstrated the need for efficient fire suppression methods.  The new device works to suppress flames using conductive aerosols, which are small particles that can direct electricity.

The device uses vortex rings – small donut-shaped bands of air – that transform the aerosol particles into short pulses of wind that convert nearby oxygen into ozone.  This accelerated airflow generates rapid turbulence, which disrupts the natural combustion process and quickly extinguishes the target fire.

The device resembles a small bucket, attached to an arm brace.  Firefighters would aim the bucket toward the fire, and it would use bursts of compressed air to deliver aerosols in an electric arc to fight the fire.

Testing identified a coarse copper solution for the vortex ring material and simulations showed that the device would succeed in suppressing fires.  They then worked on optimizing the power and range of the device.

Depending on the size of the fire and number of firefighters, it is likely that several of the devices would be required in a real emergency.  According to the developers, the design of the vortex launcher is actually very simple and is very scalable.  The device is maneuverable in tight spaces and could be taken through doors and indoor environments.  Vortex rings can carry chemical payloads over longer distances than other methods, making firefighters safe by staying further from flames. 

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New device uses electrically assisted wind to fight fires

Photo, posted November 12, 2024, courtesy of the USDA Forest Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The warmest year on record

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It came as no surprise that 2024 ended up as the warmest year on records. It was the hottest year since record keeping began in 1880.  The global average temperature was 1.28 degrees Celsius (or 2.3 degrees Fahrenheit) above the 20th-century baseline period of 1951-1980.  It was actually 1.47 degrees above the 1850-1900 average.

The Paris Climate Agreement has a goal to keep the global average temperature increase below 1.5 degrees Celsius over the long term.  Long term is specified because for more than half of 2024, average temperatures were more than 1.5 degrees above the baseline.

The temperature of an individual year can be influenced by various natural climate fluctuations, such as the presence of an El Niño or a La Niña condition in the Pacific, or volcanic eruptions.  A strong El Niño began in 2023 and continued throughout much of 2024.  That El Niño has abated, so it is no longer a factor in the global climate condition.

The global temperature is determined using surface air temperature data collected from thousands of meteorological stations as well as sea surface temperature data collected by ships and buoy-based instruments. 

When the climate changes, it is observed first in the global mean temperature.  Then there are changes seen on a continental scale and then at the regional scale.  Finally, changes are observable at the local level.  These changes are becoming more and more common as people’s everyday weather experiences become different from any they had encountered before.

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2024 Was the Warmest Year on Record

Photo, posted August 26, 2015, courtesy of Saskia Madlener / NASA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Cold spells and global warming

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January saw some major bouts of subfreezing temperatures across much of North America and significant snowfall in places like Pensacola, Florida and New Orleans.  This spate of frigid weather undoubtedly prompted many people to question whether global warming is really happening.  But such cold spells quite likely are not happening in spite of global warming, but actually as a result of it.

The polar jet stream is a slim band of westerly winds that circles the Arctic.  It is formed where cold air from the north meets warmer air to the south.  As the planet warms, the Arctic has been heating up nearly four times faster than the rest of the planet, which narrows the difference in temperature between the northern air and southern air.  The result is that the jet stream is weaker and more meandering, which allows frigid air to reach further south.

The polar vortex is a whirling mass of cold air that extends across the Arctic.  It is stronger in the winter when the Northern Hemisphere leans away from the sun.  The polar jet stream normally holds on to the vortex and keeps it far to the north.  But when the jet stream gets wobbly, this mass of cold air can break out and travel south, even to places like Florida, Louisiana, and Texas.

The planet as a whole is warming, and the Arctic is warming even faster.  But there will still be plenty of ice, snow, and frigid air in the Arctic winter for decades to come.  As the behavior of the polar jet stream gets increasingly erratic, there may well be more frequent episodes of plunging temperatures in areas unaccustomed to them.

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Severe Cold Spells May Persist Because of Warming, Not in Spite of It

Photo, posted January 5, 2025, courtesy of Dermot O’Halloran via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Fertilizer from thin air

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Ammonia is one of the largest-volume synthetic chemicals produced in the world. Globally, manufacturing plants produce about 200 million tons of it each year.  About 70% of ammonia is used to produce fertilizers.

Most ammonia is produced using the Haber-Bosch process, which converts hydrogen and nitrogen into ammonia.  The process is energy-hungry, running at over 900 degrees Fahrenheit, and therefore results in lots of greenhouse gas emissions – about 1% of the world’s annual CO2 emissions.

Researchers at Stanford University and King Fahd University in Saudi Arabia have developed a prototype device that can produce ammonia using wind energy to draw air through a mesh.  The method allows sustainable production of ammonia using the nitrogen in the air.

The process gets nitrogen from the air along with hydrogen from water vapor.  A mesh coated with catalysts facilitates the necessary chemical reactions.  The process operates at room temperature and standard atmospheric pressure, eliminating the need  for the high temperatures and high pressures of the Haber-Bosch process.

In principle, farmers could run a portable device onsite, eliminating the need to purchase and ship fertilizer from a manufacturer. 

The device is two or three years away from being market ready.  The developers are designing increasingly large mesh systems to produce greater quantities of ammonia.  Ammonia has more uses beyond fertilizers including its use as an energy carrier that can store and transport energy more efficiently than hydrogen gas.

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New device produces critical fertilizer ingredient from thin air, cutting carbon emissions

Photo, posted September 2, 2013, courtesy of Chafer Machinery via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Planting trees in Europe

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Planting lots of trees is one of many strategies being pursued to combat climate change.  Trees are storehouses of carbon from the atmosphere and planting more of them helps remove carbon dioxide.  But trees do more than that.  Trees are natural air conditioners in cities.

Trees significantly cool urban environments by providing shade and via a process called evapotranspiration by which they release water vapor into the air, which provides cooling.  This helps mitigate the urban heat island effect. Areas under trees in cities can be as much as 25 degrees cooler than in unshaded areas covered in asphalt.

The city of Paris has laid out a plan to help the city prepare for increasing amounts of extreme heat.  The goal is to replace 60,000 parking spaces across the city with trees by the end of this decade.  The plan to rip up parking spaces is part of a greater aim to create more than 700 acres of green space by 2030.  The Paris plan also includes creating more car-free zones and installing reflective roofs on 1,000 public buildings.  Nearly 80% of the buildings in Paris have zinc roofs – an affordable, corrosion-resistant and pretty much inflammable innovation of the 19th century.  However, these roofs can heat up to 194 degrees on a summer day, transferring heat into largely uninsulated top-floor garrets below.

Elsewhere in Europe, Danish lawmakers have agreed on a plan to rewild 10% of the country’s farmland and plant one billion trees.   According to the Danish government, this plan would bring about the biggest change to the Danish landscape in over 100 years.

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To Cope with Extreme Heat, Paris Will Swap Parking Spaces for Trees

Photo, posted April 11, 2014, courtesy of Val H. via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Dangers of distant fires

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Smoke from wildfires is well known to exacerbate health problems like heart disease, lung conditions, and asthma.  People living in the vicinity of where fires occur face these dangers.  But a new study at the University of Maryland has found that there are health impacts from wildfires occurring thousands of miles away.

During the summer of 2023, massive Canadian wildfires created a vast plume of smoke that drifted more than 2,000 miles across the country resulting in poor air quality across the entire East Coast of the U.S. 

Baltimore had very dark skies over a six-day period in June 2023, sending many individuals to doctors’ offices complaining of breathing issues.  University of Maryland researchers found that medical visits for heart and lung problems rose by nearly 20% during that period.

Using satellite and EPA data combined with electronic health records, the researchers found increased likelihood of patients going to the doctor for complications related to cardiopulmonary conditions during the days with the most smoke in the air.  They found a 55% increase in the risk for an outpatient visit for heart and lung conditions and these additional patients tended to be older, non-smokers, and more socio-economically affluent than the typical patients who see their doctors for such conditions when the air quality is good.

With more climate-related events likely to occur in the future, doctors may require better tools to help disadvantaged patients on so-called hotspot days when conditions are most dangerous.  Increasingly common wildfires are a particular danger to people even when those fires are far away from where they live.

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Exposure to Remote Wildfire Smoke Drifting Across the U.S. Linked to Increased Medical Visits for Heart and Lung Problems

Photo, posted June 8, 2023, courtesy of Marc A. Hermann / MTA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Thermal batteries for heavy industry

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Heavy industries like cement, steel, chemicals, and paper require large amounts of heat and, for the most part, that heat comes from burning fossil fuels.  Other sectors of the economy have been making progress in reducing carbon emissions, but heavy industry has not found easy answers for supplying the heat it needs for manufacturing.

Researchers at MIT have developed a way to supply heat that only uses electricity, which in principle can come from carbon-free sources.  The idea is to use thermal batteries.  These are basically an electrically conductive equivalent of ceramic firebricks, which have been used to store heat for centuries in fireplaces and ovens.

A spinout company called Electrified Thermal Solutions has demonstrated that its firebricks can store heat efficiently for hours and release it by heating air or gas up to 3,272 degrees Fahrenheit. 

The firebrick arrays are contained in insulated, off-the-shelf metal boxes.  The standard system can collect and release about 5 megawatts of energy and store about 25 megawatt-hours.  The thermal battery can run hotter and last longer than any other electric heating solution on the market.

Using this technology can be a way to take advantage of the low cost of electricity in off-peak hours.  In the so-called wind belt in the middle of the U.S., electricity prices can even be negative at times.  Using the firebrick technology – called the Joule Hive Thermal Battery – it can be possible to provide industrial heating capability at very competitive prices, and that doesn’t even factor in the positive climate impact.

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Decarbonizing heavy industry with thermal batteries

Photo, posted April 19, 2019, courtesy of Hans M. via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Neighborhood geothermal energy

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Residential geothermal energy makes use of the constant, year-round temperature of the earth below the surface to efficiently provide both heating and cooling for a home.  In the summer, the cool earth beneath a house sits at about 55 degrees and can be tapped into with a heat pump to provide cooling.  In the winter, that 55-degree underground expanse provides a much warmer source of air to heat instead of the often freezing-cold air outside.  Geothermal systems are appealing because they use far less energy than other sources of heating and cooling.

Using geothermal energy to heat and cool buildings is nothing new.  But after years of planning and months of drilling into the ground, the first neighborhood-scale geothermal heating and cooling project has come online in Framingham, Massachusetts.

The project ties together 31 residential and five commercial buildings that share the underground infrastructure needed to heat and cool them.  This sort of shared geothermal system has previously been used on college campuses and similar places, but never before across a neighborhood in the United States.

The $14 million project, built by Eversource, broke ground in June 2023, and comprises 90 boreholes or wells drilled 600-700 feet underground. Approximately 135 customers are connected to the system, including low- and moderate-income customers, apartment buildings, a gas station, and a kitchen cabinet showroom.

A total of 13 states, including Massachusetts and New York, are considering pilot projects or advancing legislation that would allow gas utilities to develop networked geothermal heating and cooling.

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First-in-the-Nation Geothermal Heating and Cooling System Comes to Massachusetts

Photo, posted September 30, 2019, courtesy of Stephen D. Strowes via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Giant batteries in the Earth

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The wind and the sun are inexhaustible sources of energy, and we are tapping into them to produce electricity at a growing rate around the world.  But neither of them is always available when we need them.  When the sun isn’t shining and the wind isn’t blowing, they don’t work.

An opposite problem also exists.  When our energy needs are low, but it is sunny or windy, solar and wind power are all dressed up with nowhere to go.  Energy storage is the answer to both of these problems.   When there is excess generation, store the energy for later use.  When there is need for energy and not enough is being generated, tap into the energy that is stored.

Giant banks of lithium-ion batteries are the rapidly growing form of energy storage, and they are increasingly providing resilience in the electric grid.  But battery storage is short-term energy storage.  Even the largest battery banks can only provide a few hours of electricity. 

So, there is a real need for “long-duration energy storage” – systems that provide at least 10 hours of backup power and sometimes much more – for the grid to be fully reliable.

Pumped hydro storage, which uses water from elevated reservoirs to drive turbines, has been around for a long time.  Historically, this is the largest form of energy storage in the world.  Other methods include pumping compressed air into underground caverns or lifting massive blocks into elevated positions.  All of these techniques use excess electricity to place things like water, air, or cement into a position where they can be used to drive electrical generators.

The grid of tomorrow will store energy in giant battery banks, but also in the ground, in reservoirs, and in large structures.

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How giant ‘batteries’ in the Earth could slash your electricity bills

Photo, posted March 21, 2024, courtesy of Sandra Uecker/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Artificial plants to clean indoor air

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The average American spends about 90% of their time indoors breathing the air in our workplaces, homes, or schools.  The quality of this air affects our overall health and well- being.  Indoor air quality is an issue because many sources can generate toxic materials, including building materials, carpets, and more.  But high levels of carbon dioxide are a health hazard themselves. Indoor CO2 levels can often be 5 to 10 times higher than the already heightened levels in the atmosphere. 

Many of us make use of air purification systems, which can be expensive, cumbersome, and require frequent cleaning and filter replacements.

Researchers at Binghamton University in New York are working to develop artificial plants that consume carbon dioxide, give off oxygen, and, as a bonus, generate a little electricity. These artificial plants make use of the artificial light in the indoor environment to drive photosynthesis.  They achieve a 90% reduction in carbon dioxide levels, which is far more than natural plants can achieve.

The Binghamton researchers had been working on bacteria-powered biobatteries for various applications, but they repurposed the work into a new idea for artificial plants.  The artificial plants have “leaves” containing a biological solar cell and photosynthetic bacteria.  Their first plant had five leaves and demonstrated promising carbon dioxide capture rates and oxygen generation.  It also produced a little electricity.  If its generating capacity can be improved, it might also be useful for charging cell phones or other practical applications.

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Binghamton researchers develop artificial plants that purify indoor air, generate electricity

Photo, posted October 13, 2012, courtesy of F. D. Richards via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Rainfall and sea turtles

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There are seven species of sea turtles that inhabit the world’s oceans. Six of the seven sea turtle species – all of them except the flatback – are present in U.S. waters, and are listed as threatened or endangered under the Endangered Species Act. 

Sea turtles, which have been around for more than 100 million years, spend the majority of their lives in the ocean, but they do periodically come ashore to nest.  Female sea turtles lay their eggs in the sand and then return to the ocean.  Survival odds for sea turtle hatchlings are quite bleak.  In fact, only one out of every 1,000 makes it to adulthood. 

Research shows that both air and sand temperatures are critical for sea turtle hatchling development.  Cooler temperatures produce larger, heavier hatchlings with more males.  Hatchling size matters because larger hatchlings, which can move faster, are more likely to survive because they spend less time on risky beaches.  But rising temperatures might shorten incubation periods, and erratic rainfall can disrupt growth, potentially affecting survival.

A new international study by researchers from Florida Atlantic University and the University of Tübingen in Germany found that fluctuating rainfall patterns have a greater impact than changes in air temperature on sea turtle hatchling development. 

The results, which were recently published in the journal BMC Ecology and Evolution, reveal that the impact of rainfall varies between species.  As climate change shifts rainfall patterns, the impact on sea turtle nesting sites suggests that global conservation strategies for some species – like loggerhead and green sea turtles – likely need to be updated.

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Rain or Shine? How Rainfall Impacts Size of Sea Turtle Hatchlings

Sea Turtle

Photo, posted August 27, 2015, courtesy of USFWS/Orsulak via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Water from thin air

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The Earth’s atmosphere contains enormous amounts of water.  Being able to efficiently and economically extract some of it to provide drinking water would be extremely beneficial to the billions of people across the globe who face chronic water shortages.

There are existing technologies for atmospheric water harvesting – or AWH.  But there are downsides associated with size, cost, and efficiency.   A new device developed by mechanical engineering researchers at the University of Utah has the potential to provide a new drinking water source in arid places.

The device is a compact, rapid-cycling, fuel-fired AWH device.  It relies on adsorbent materials that draw water molecules out of non-humid air and then applies heat to release those molecules into liquid form.

Hygroscopic materials are those that have an affinity for water and soak it up at every opportunity.  Such materials are used, for example, in disposable diapers.  The Utah device makes use of metal organic frameworks, which have enormous amounts of surface area on the molecular scale.

The initial work on the Utah device targeted a small compact water generation unit for soldiers in the field.  Instead of lugging around a large canteen filled with water, the small unit can produce water on demand.  The prototype was able to produce 5 liters of water per day per kilogram of adsorbent material.  Within three days in the field, the system outperforms packing water.  The heat required to precipitate the liquid water was provided by a standard-issue Army camping stove.

Non-military needs are the ultimate application for the device.  The researchers have applied for a patent for what they hope will be a potential solution to a persistent global problem.

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Producing water out of thin air

Photo, posted August 9, 2012, courtesy of Enid Martindale via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Cooling cities

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As the climate warms, city dwellers tend to suffer from extreme heat more than people in rural areas because of the urban heat island effect. Extensive surfaces of man-made materials like concrete, asphalt, and brick absorb the sun’s energy and lead to temperatures well above those in the surrounding countryside.

Cities can take countermeasures that include creating urban green spaces full of plants that cool the surrounding air and the use of cool roofs that reflect the sun’s energy back into space.  Local governments in many cities provide incentives for planting more trees.  But more could be accomplished by encouraging the use of cool roofs.

The heat island effect has been well-known for a long time, but scientists are only recently learning what interventions are most effective. A recent study modeled two days of extreme heat in London in 2018 and compared the potential effects of cool roofs, green roofs, roof-top solar panels, and ground level vegetation. They found that cool roofs are the most effective way to lower temperatures and would have reduced London temperatures by 2 degrees on average and as much as 3.6 degrees in some places.

Cool roofs are created by swapping out dark, heat-absorbing roofing materials with reflective materials or simply by painting roofs white. Los Angeles is the first major city to require that all new residential construction includes a cool roof. 

Apart from the effectiveness of passive cooling techniques, using them also reduces the reliance upon air conditioning to protect people from heat.  Air conditioners themselves contribute considerable amounts of heat to urban environments.

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The surprisingly simple way cities could save people from extreme heat

Photo, posted February 21, 2024, courtesy of Warren LeMay via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The end of the Chevron deference

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 At the end of June, the US Supreme Court upended 40 years of legal precedent in a ruling that sharply limited the regulatory authority of federal agencies.  The so-called Chevron Deference doctrine stated that when a legislative delegation to an administrative agency on a particular issue or question was not explicit but rather implicit, a court may not substitute its own interpretation of the statue for a reasonable interpretation made by the administrative agency.

Under the new ruling, courts will have more power to interpret these statutes.  Environmentalists fear that this decision could lead to hundreds of rules being weakened or even eliminated, particularly Environmental Protection Agency limits on air and water pollution, regulations on toxic chemicals, and policies to tackle climate change.

Conservative political organizations have been pushing for decades to roll back the government’s regulatory powers.  The new ruling creates a massive opportunity for environmental regulations to be challenged, considering the proliferation of increasingly activist, right-leaning courts.  In particular, climate regulations under the Clean Air Act are more susceptible to judicial reversal.  The ruling shifts the power from the agencies to the courts.

The danger of this decision is that more Americans will suffer from the worse effects of climate change, air pollution, and other environmental harms that current government regulation protect against.  Any time that the Court makes it harder for the government to regulate and easier for businesses to challenge regulations, it makes it more likely that industries will injure the public and the planet in search of profits.  This is basic economics in action.

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A Seismic Supreme Court Decision

Photo, posted September 17, 2020, courtesy of Thomas Hawk via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Biofuel refineries and toxic pollution

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There have been decades of government support for renewable, crop-based fuels – primarily corn ethanol.  In fact, it is a required component of gasoline sold in this country.  The biofuels industry has long claimed ethanol to be a clean, greener alternative to petroleum. 

There have been arguments all along that the environmental benefits of corn ethanol are dubious at best because of the energy required to produce the stuff.  There are also issues related to burning a food crop instead of feeding it to people and that the conversion of grasslands and forests to produce it releases massive amounts of carbon.

Recently, another serious concern has emerged.  A new review of industry data has found that the country’s biofuel refineries, mostly located in the Midwest, produce large amounts of toxic air pollutants, in some cases ever more than from their petroleum counterparts.

Emissions data from the country’s 275 ethanol, biodiesel, and renewable diesel plants revealed that they release carcinogenic formaldehyde as well as other potentially dangerous substances including acetaldehyde, hexane, and acrolein.  In 2022, biofuel refineries released 12.9 million pounds of hazardous air pollutants, compared to 14.9 million pounds emitted by oil refineries, and the biofuel plants actually emitted more of the four chemicals just mentioned than petroleum refineries did.

The broad use of crop ethanol is the result of intensive industry lobbying.  Ethanol plants are even exempt from some air pollution permitting requirements.  Perhaps the time has come to revisit its pervasive and mandated use.

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Biofuel Refineries Are Releasing Toxic Air Pollutants in Farm Communities Across the US

Photo, posted February 27, 2021, courtesy of Sue Thompson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A brief bout of bad air in Scotland

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Scotland, and the UK in general, used to suffer from sulfur dioxide pollution.  Industrial and domestic emissions, especially from burning coal, contributed heavily to urban air leading to the London smog of the 1950s and the acid rain of the 1980s.  But national air pollution agreements and various international measures have been highly successful in reducing sulfur dioxide emissions.  Desulfurization of coal-fired powerplants and the introduction of ultralow sulfur fuels among other measures have decreased sulfur dioxide emission by 98% since 1970. 

As a result, it came as quite a surprise on May 31st when Edinburgh saw sulfur dioxide levels higher than had been observed in over 30 years.  The levels greatly exceeded air quality objectives for 10 hours with concentrations even creeping towards workplace exposure limits.

What happened?  For once, it was nothing that people did.  Two days earlier, a volcanic fissure eruption took place in the Reykjanes Peninsula in Iceland, some 850 miles from Edinburgh.  Because of an unusual meteorological configuration, the prevailing winds sent the plume of volcanic gases southward towards Scotland.  Had the eruption taken place 60 miles further north or happened a few hours later, the plume of gases would have missed the UK entirely and would have traveled north to the Arctic region.

Icelandic volcanic eruptions have impacted air travel in Europe on a number of occasions.  This non-explosive eruption had little impact outside of its local region, but it turned out to briefly wreak havoc in Scotland.  Fortunately, this pollution event was short-lived.

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Atmospheric sulphur dioxide levels reach historic high in Scotland following Icelandic volcano eruption

Photo, posted November 17, 2021, courtesy of Catherine Poh Huay Tan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

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