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More floating solar

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Floating solar power is starting to gain some traction in the United States.  Installing solar panels on rafts so that they float on water instead of sitting on land allows them to not take up land that can be used for other purposes.  There are other benefits as well.

The world’s largest floating solar farm is one in Shandong, China, and produces 320 MW of power.  Floating solar has been common in Asia for years.  To date, floating solar only makes up a tiny fraction of the installed solar power in the U.S. and is mostly limited to small-scale projects.  The largest in the U.S. is the 8.0 MW Canoe Brook Water Treatment Plant in Millburn, NJ.  A floating solar array in the water reservoir at the Cohoes Water Filtration Plant in New York’s Capital Region is currently under construction.  A 6-MW floating solar system is now being built in the Village of Monroeville, Ohio.

Floating solar systems have the advantage that covering the surface of reservoirs dramatically reduces the amount of evaporation that occurs, which is a real benefit in drought-stricken regions like California.  In addition, proximity to the large body of water keeps solar panels cool, which allows them to generate more electricity than their land-based counterparts.

Estimates are that federally controlled reservoirs alone have the potential to host roughly 1,000 GW of floating solar capacity.  It is more expensive to install them than conventional land-based solar and floating solar competes with recreational use of bodies of water.  Nonetheless, the floating solar market is expected to grow significantly in the coming years.

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Ohio’s largest floating solar array is now under construction

Photo, posted May 28, 2025, courtesy of Mike Popp / University of Arkansas via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Waste colonialism

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Plastic pollution is a pervasive environmental problem that manifests itself in multiple ways.  Very little plastic is recycled; most of it ends up in landfills or is burned, both solutions having serious shortcomings.  High-income countries – such as many in Europe, the United States, Japan, and Australia – facing increasingly strict regulations in disposing of waste, have long grappled with the problem.

One approach they have often pursued for dealing with plastic waste is to export the waste elsewhere, preferably to countries with weaker waste regulations.  For over 20 years, China was the place to send plastic waste.  In the 1980s-90s, China accepted trash from richer countries to salvage raw materials from it.  This led to serious pollution, health risks, and illegal dumping.  In 2018, China banned the import of plastic waste.

Since then, Western countries have sent their waste to other parts of Asia and Africa. These waste exports are often advertised as contributions to recycling, but mostly, it is just a charade that simply makes the waste someone else’s problem – namely less developed countries, often with inadequate waste management infrastructure. 

This practice of developed nations consuming excessively and exporting their waste to less developed countries is known as waste colonialism.  It is a modern incarnation of historical colonialism, where natural resources and labor were stripped from colonized regions. 

Its inherent injustice aside, the practice does not solve any of the problems created by waste.  It just moves them somewhere else.

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Waste Colonialism: A Brief History of Dumping Rich Countries’ Trash in the Global South

Photo, posted February 13, 2011, courtesy of Dan DeLuca via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Restored wetlands and climate

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Forests are well-known to be major storehouses of carbon in the environment.  Less known but also extremely important are peatlands and wetlands and, like forests, both have suffered declines as a result of human activity.  And, like forests, both are seeing efforts at restoration.

Restoring peatlands has the drawback that it initially causes a spike in methane emissions, and it therefore takes a long time for them to have a net positive effect on the climate after they are restored. 

In a new study by RMIT University in Australia, it was found that reviving floodplain wetlands reduces carbon emissions by 39% and restores critical ecosystem functions in one year without any increase in methane emissions.  The 6-year study reintroduced water flow to a degraded freshwater wetland.  Over the course of the study, carbon stocks in the wetland increased by 53%.  Freshwater wetlands cover less than 10% of the Earth’s surface but contribute up to 25% of global methane emissions.  Despite this, they still play a crucial role in global ecosystem function.

Floodplain or riparian wetlands comprise over half of global wetlands.   They store less carbon than peatlands but restoring them gains substantial ecosystem benefits quickly.  The carbon is stored in plant roots and soil.  Wetlands are nature’s purification system removing both nitrogen from waterways and carbon from the atmosphere. 

Restoring and managing freshwater wetlands for the purpose of carbon sequestration also boosts flood and drought resilience.  Riparian wetlands are connected to other ecosystems like rivers and streams and provide benefits to them.

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Restored wetlands reap benefits for climate, drought-resilience after just one year: study

Photo, posted January 7, 2014, courtesy of Tom Barnes / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Return of the frogs

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The mountain yellow-legged frog is a species that lives in the mountains of Southern California.  It is listed as an endangered species for protection by the federal government.   Surveys 20 years ago determined that the frog’s population was declining and on a trajectory toward extinction.  The frogs are severely impacted by water pollution and are vulnerable to the effects of wildfires, floods, disease, and drought.

A collaboration headed by the Scripps Institution of Oceanography at UC San Diego along with the San Diego Zoo Wildlife Alliance, UCLA, and the Big Bear Alpine Zoo has been raising mountain yellow-legged frogs in captivity as part of a long-running recovery program with partners at multiple federal and California state agencies.

In August, more than 350 of the frogs were reintroduced into the wild in Southern California’s San Bernardino Mountains, one of the largest releases of the captive-raised frogs to date.  This represented the first species reintroduction by the Scripps Institution and an important milestone in its growing conservation work.

The frogs were transported in coolers to the mountains where a team then hiked the frogs to three sites along a lake within a protected reserve.  The frogs were microchipped with passive transponder tags that will allow researchers to identify individuals during future surveys.  This will enhance long-term monitoring and inform ongoing conservation efforts.

The goal of these efforts is to help to delist or at least downlist the endangered status of the frogs by enhancing the genetic diversity of both captive and wild populations, optimizing reintroduction efforts, and increasing wild frog populations.

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Hundreds of Mountain Yellow-legged Frogs Leap Back Into the Wild

Photo, posted April 27, 2011, courtesy of Rick Kuyper / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Energy storage in New York isn’t easy

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The state of New York has the ambitious goal of having 70% of its electricity come from renewable sources in 2030 and a 100% zero-emission electric grid by 2040.  Meeting these goals is becoming increasingly unlikely as the state faces multiple challenges including local opposition to projects, rising inflation, and the termination of offshore wind projects.

Solar and wind power are key elements of New York’s renewable plans, and both require battery energy storage so that excess energy can be saved when there is plentiful sun and wind so that there will be power available when nature hasn’t cooperated.

There are now over 6,000 battery storage projects in the state, mostly relatively small in magnitude.  Currently, the state has a storage capacity of about 445 megawatts, enough to power roughly 300,000-400,000 homes.  The state has a goal of having 6 gigawatts of storage by 2030, more than a dozen times more than exists today.

Most of New York’s electricity demand is downstate, in and below the Hudson Valley.  Real estate is limited and expensive and there is lots of opposition to big energy projects in the region. 

However, installing the actual battery systems themselves can be one of the easier parts of the process.  Obtaining permits from state and local authorities, buying or leasing land, negotiating with grid operators, completing environmental reviews, overcoming local opposition, and especially, connecting to the electric grid, are all challenging and very time consuming.

Meeting the state’s energy storage goals is not easy.

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Figuring Out a Battery Storage System to Fit New York’s Wind and Solar Ambitions Has Not Been Easy

Photo courtesy of NineDot Energy.

Earth Wise is a production of WAMC Northeast Public Radio

Trying to replace neonics

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Neonicotinoids – often called neonics – are a class of insecticides that are among the most widely used in agriculture.  They are neuro-active, meaning that they affect the central nervous system of insects, killing or harming a wide variety of both target and non-target insects.  They are often applied to seeds before planting as a prophylactic treatment for potential insect pests.

Neonics have been linked to adverse ecological effects, especially the harm they cause to bees and other pollinators.  The Birds and Bees Protection Act in New York State, signed into law in 2023, is phasing out the sale, distribution, or purchase of certain neonic-treated corn, soybean, and wheat seeds over the next few years. 

A multi-year, multi-state study by researchers at Cornell University investigated the ability of a variety of non-neonicotinoid insecticides to protect large-seed vegetable crops including snap beans, dry beans, and sweet corn.  It is a difficult problem because insecticides kill insects, and it isn’t easy to find ones that kill pests but have minimal effects on pollinators and other beneficial insects.

The research found safer alternative insecticides with comparable effectiveness for treating snap bean seeds but not for dry beans. Much more successful was the result that five alternative seed treatments proved as effective as standard neonics for sweet corn while having far fewer negative environmental impacts.  Sweet corn is a major crop in New York state, so these results could be of great importance in improving the long-term sustainability of pest management programs.

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New pesticides provide challenging alternatives to neonicotinoids

Photo, posted May 31, 2021, courtesy of Papa Piper via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Five-minute car charging

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A long-standing complaint about electric cars is the amount of time it takes to charge their batteries.  A decade ago, this was a serious shortcoming.  Even at the fastest chargers available at the time, it could take hours to refill the electric fuel tank.  Combined with the limited range earlier electric cars had, this made long-distance road trips in an electric car something only for the adventurous.

Nowadays, electric cars can go much further on a charge – 300 miles and more – and the fastest public chargers can add 200 miles in 20 minutes.  With this kind of performance, electric cars are eminently practical for the great majority of drivers and the great majority of road trips.  But for some people, it just isn’t good enough.  They want to be able to charge up a car as fast as they can fill up a tank of gas.

That capability is about to be available in China.  Two Chinese companies announced technology breakthroughs that will allow electric cars to add 250 miles of range in five minutes.  China is the world’s largest user and producer of electric cars, and the country has invested heavily in charging technology, especially in the infrastructure enhancements required for high-speed charging.

When will this capability be available in the United States?  It isn’t clear.  The Trump Administration has been aggressively rolling back policies that support the EV industry.  The regulatory changes that would permit higher-power charging stations are unlikely to happen any time soon.

Electric cars are already very practical for most people, but if one wants them to be able to please everyone, one may have to go to China.

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Why Can’t the U.S. Build 5-Minute E.V. Chargers?

Photo, posted April 17, 2023, courtesy of FirstEnergy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Help from elephants in cooling buildings

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Elephant ears play a crucial role in keep the giant animals cool.  Elephants don’t have significant sweat glands.  Instead, they rely on their large ears to regulate body temperature.  Their ears make up 20% of their body’s surface area.  The ears act like a natural air conditioner, making use of a network of blood vessels close to the surface that help dissipate heat when it’s hot and absorb heat when it’s cold.

Researchers at Drexel University have developed a new approach to passive heating and cooling that has the potential to make buildings more energy efficient.  The idea, published in the Journal of Building Engineering, embeds the equivalent of a vascular network within cement-based building materials.  The network, when filled with paraffin-based material, can help passively regulate the surface temperature of walls, floors, and ceilings.

Building energy demand contributes almost 40% of the production of greenhouse gas from energy use, and about half of building energy use is spent maintaining comfortable temperatures.

The new temperature regulation method puts a grid of paraffin-filled channels in the surface of building concrete.  When temperatures drop, the paraffin transitions from liquid to solid and releases heat energy.  When ambient temperatures rise, the paraffin absorbs heat energy, producing a cooler surface.  This is essentially the same way elephants as well as jack rabbits regulate their temperatures with their large ears.

The Drexel study was a proof-of-concept effort, but the results are promising enough to warrant further work.  With additional testing and scaling, it has the potential to make a significant contribution to ongoing efforts to improve the energy efficiency of buildings.

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Drexel Engineers Want to Make Buildings More Energy Efficient by Making Walls, Floors and Ceilings More Like Elephant Ears

Photo, posted September 1, 2016, courtesy of Nane Kratzke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Super drivers and electric cars

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The average American driver travels about 13,400 miles a year. The top 10% of drivers average about 40,200 miles a year and account for 35% of the nation’s gasoline use from private light-duty vehicles, meaning cars, SUVs, pickup trucks, vans, and minivans.  Those 21 million Americans alone burn more gasoline than is burned each year in Brazil, Canada, and Russia combined.

These super drivers often live in rural areas and small towns, drive an average of 116 miles each weekday, and typically own vehicles that are larger and less fuel efficient.  Many have long commutes to work because they were pushed out of cities by rising housing prices.  Some are tradespeople who travel from site to site all day in their jobs. 

Given the disproportionate amount of gasoline usage by this small segment of the population, the key to cutting vehicle emissions by adopting electric vehicles may rest with super drivers.  And so far, not many of them have made the transition.

A report by the environmental nonprofit group Coltura contends that getting super drivers to switch to electric cars would lead to a much faster reduction in emissions.

The range of most recent electric cars is sufficient for most super drivers.  The obstacles remaining include availability of convenient charging stations, but that is changing.  Finding the right vehicle might also be a problem, but electric pickup trucks and large SUVs are entering the market. 

The transition to electric vehicles is important for society, and the most active drivers need to take part in it.

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Are You a Super Driver? Some States Want to Help You Go Electric.

Photo, posted January 9, 2025, courtesy of Phillip Pessar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

What happened to the sea stars?

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Billions of sea stars off the Pacific coast of North America from Mexico to Alaska have died from a wasting disease since 2013.  This die-off is considered to be the largest ever marine epidemic.  Over 90% of the population of sunflower sea stars has succumbed to the disease.

The result has been an explosion in the population of the sea urchins that the sea stars feed on.  In turn, the sea urchins have devoured kelp forests that provide habitat for thousands of marine creatures.  These kelp forests support a multi-million-dollar economy through fisheries and tourism as well as sequestering carbon dioxide and protecting vulnerable coastlines. 

The disease begins with lesions and eventually kills sea stars by seemingly melting their tissues over a period of about two weeks.  Sea stars with the disease become contorted and lose their arms.

For years, the definitive cause of the wasting disease has been elusive.  But researchers from the University of British Columbia, the Hakai Institute, and the University of Washington have now identified a bacterium that is the disease-causing agent.

A strain of the Vibrio pectenicida bacteria – named FHCF-3 – is responsible.  The Vibrio genus of bacteria includes pathogens that infect corals, shellfish, and even humans.  Vibrio cholerae is the cause of cholera.

Research is now underway to understand the link between the disease and warming ocean temperatures due to climate change.  The hope is that the discovery of the cause of the wasting disease will help guide management and recovery efforts for sea stars and impacted ecosystems.

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‘Disease detectives’ discover cause of sea star wasting disease that wiped out billions of sea stars

Photo, posted April 16, 2011, courtesy of Brian Gratwicke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Energy droughts

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With new ways of doing things, there are always new problems.  Our energy systems are increasingly dependent upon solar and wind power.  These energy sources are free to take and aren’t going to run out, but they also depend on natural processes that are out of our control.  In particular, the sun doesn’t always shine, and the wind doesn’t always blow.

Fortunately, the two sources of energy are typically not in sync and often when one is diminished, the other can take up the slack.  But it is possible for both sun and wind to not be present, and it can even happen for an extended period of time.  This is known as a compound energy drought. There are some parts of the country where these energy droughts can last for nearly a week.

Researchers at the Pacific Northwest National Laboratory studied the phenomenon and its potential impact on the electric grid.   Looking at 40 years of weather data, the study found that the longest energy drought occurred in California for 6 days; the longest in Texas was 37 hours.

The study further investigated the possible connection between energy droughts and energy demand, again mapping historical data over the past 40 years.  The impact of an energy drought depends on how much demand for energy exists at the time.

The data from the study will provide critical insights into the design and management of multi-day energy storage facilities that can provide the resilience of the electric grid that is required.  Clearly, the storage needs in a place like California will be substantially greater than those in Texas.  As more and more of the grid depends on wind and solar power, appropriately designed and operated storage facilities will be essential.

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“Energy Droughts” in Wind and Solar Can Last Nearly a Week, Research Shows

Photo, posted February 10, 2023, courtesy of Guilhem Vellut via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Harmful algal blooms and climate change

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An algal bloom is a rapid increase in the density of algae in an aquatic system.  Harmful algal blooms occur when bodies of water get overloaded with nitrogen and phosphorus runoff from agriculture and other human activities. These excess nutrients can facilitate the out-of-control growth of cyanobacteria, also known as blue-green algae. 

Some species of blue-green algae produce a toxin called microcystin.  These toxins pose a serious health hazard to people, animals, and the environment.  Microcystin affects liver function and can cause death in animals, as well as humans in rare instances.  A notable incident occurred in the summer of 2014, when cyanobacteria contamination in Lake Erie left 500,000 residents in Ohio and Michigan without water for 72 hours and sickened more than 100 people. 

According to a study led by researchers from Carnegie Science, as climate change warms the earth, higher-latitude regions will be at a greater risk for microcystin produced by algal blooms.  The study found water temperatures of 68 to 77 degrees Fahrenheit as being at the greatest risk for developing dangerous levels of microcystin. 

In the study, which was published in the journal Nature Water, the research team also demonstrated that the areas most susceptible to high toxin concentrations will continue to move northward. And in some areas, researchers say the relative risk of exceeding water quality guidelines will increase by up to 50% in the coming decades.

The research team hopes its findings raise more awareness about water sustainability, and the need to focus on the quality of the water as much as the quantity of water. 

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Geographic redistribution of microcystin hotspots in response to climate warming

Photo, posted October 27, 2010, courtesy of Nara Souza / Florida Fish and Wildlife Commission via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Abandoned farmland and the environment

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Abandoned farmland has been increasing dramatically in recent decades.  Estimates are that a billion acres – an area half the size of Australia – have been relinquished from cultivation globally.  While more and more of the tropics have been cultivated in recent times, the global amount of land used for agriculture has been in decline since 2001.  In the past 30 years, arable land in the United States has declined by almost a sixth.  The situation in Europe is similar.  Huge amounts of the former Soviet Union now lie abandoned. 

Farmland is abandoned for various reasons.  It may suffer from damaged soil so that crop yields are too low to be worth the effort.  Farm owners may become too old or be physically unable to continue farming.  Many younger people head for jobs in the cities and more attractive opportunities.  Wars, natural and man-made disasters, and political turmoil have all contributed.

Another form of largely ignored lands are so-called degraded forests.  These are forests that were logged in the past but are no longer productive and aren’t protected either.  These places also represent unused land with great potential value.

Ecologists point to the potential of these lands as neglected resources for rewilding efforts, improving biodiversity, and for increasing natural ways to capture carbon.  Left to its own devices, nature will usually reclaim abandoned places.  This generally provides benefits for biodiversity and climate.  But mapping, studying, managing, and protecting the increasingly vast tracts of abandoned land could increase their potential to contribute to climate change mitigation and the restoration of species and their habitats.

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Abandoned Lands: A Hidden Resource for Restoring Biodiversity

Photo, posted January 26, 2023, courtesy of Larry Syverson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Supermarket bargains and food waste

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Food waste is a major global problem.  The UN estimates that one third of all food goes to waste.  Apart from the fact that this is happening in a world where many people don’t have enough to eat, food waste is both an economic and a climate problem.

Researchers from the University of Copenhagen and Southern Methodist University investigated how different types of grocery sales strategies affect people’s shopping and food waste.  The result was that bulk offers increase food sales by nearly 20%, but they also lead to increased food waste in people’s homes.

The study analyzed over 43,000 purchases of fresh vegetables in eight Swedish supermarkets.  When customers were offered “two-fer” offers, they bought significantly more than when only single items were available.  The attraction of a special offer can be strong.  But, according to a follow-up survey, food from bulk offers ended up in the trash more often.  People thought they were saving money, but often ended up buying more than they can eat.

The researchers tested two strategies for reducing overbuying.  One was to make the actual savings explicit by displaying the regular price next to the offer.  The second was to put a friendly reminder on the offer sign along the lines of “I’d love to come home with you if you eat me.”  Both of these approaches resulted in reduced sales of 9-11% compared to the original volume offer despite the sale price remaining the same. 

Clearly, small changes in marketing can make a big difference.  Supermarkets play a big role in the occurrence of food waste and they have the ability to help nudge consumers into better behavior.

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Good deals – bad for the climate: Supermarket volume discounts lead to food waste

Photo, posted November 13, 2006, courtesy of Josh Hallett via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Recycling solar panels

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The use of solar energy has been growing by leaps and bounds in recent years. It is the fastest growing source of energy in the U.S.   Solar panels have a useful life of about 25 to 30 years and there are growing numbers that have been around that long.  They contain valuable materials, including silver, copper, and aluminum, as well as some hazardous materials, so just committing them to landfills is a bad idea from many perspectives.

Recycling solar panels is a relatively new but increasingly important business.  At the present time, roughly 90% of panels that have lost their efficiency due to age or that are defective end up in landfills because that is much cheaper than recycling them.  The best option is to reuse them where their reduced efficiency is acceptable.  This includes in developing nations or in other places that are able to make use of the lower power in exchange for lower installation cost.

Estimates are that the area covered by solar panels in the U.S. that are due to retire by 2030 would cover about 3,000 football fields.   The amount of potential waste contained in all of those panels is quite substantial.

There are new companies dedicated to solar panel recycling such as one called SolarCycle that are trying to change this situation.  It is much more expensive to have SolarCycle take away solar panels than to send them to landfills, but it is difficult to find landfills that accept panels and many clients want to minimize the environmental impact of their old panels.

Only 10% of retired solar panels are currently recycled. That that is likely to change as economics and regulations continue to evolve.

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As Millions of Solar Panels Age Out, Recyclers Hope to Cash In

Photo, posted November 23, 2024, courtesy of Mussi Katz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Air pollution and human health

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Climate change is making air quality worse in many parts of the world. Rising temperatures increase ground-level ozone, and more frequent wildfires release harmful smoke and particulates into the air. These changes, combined with ongoing pollution from sources like vehicle exhaust and industrial emissions, lead to longer and more intense episodes of unhealthy air.

A new study led by researchers from the University of Toronto in Canada examined more than 600 people and found that long-term exposure to air pollution is associated with early signs of heart damage.  The research, which was recently published in the journal Radiology, indicates that fine particulate matter in the air may contribute to diffuse myocardial fibrosis, a form of scarring in the heart muscle that can precede heart failure. 

Cardiovascular disease is the leading cause of death worldwide. 

Long-term exposure to common air pollutants is also linked to a significantly higher risk of dementia.  A separate study by researchers from the University of Cambridge in the UK analyzed data from nearly 30 million people and found that for every 10 micrograms of fine particulate matter per cubic meter of air, the risk of dementia increases by 17%.  The study, which was recently published in The Lancet Planetary Health, found that exposure to nitrogen dioxide and soot was also strongly associated with an increased risk of dementia.

Dementia is estimated to affect more than 57 million people worldwide, a number that is expected to swell to 152 million by 2050.

Strengthening efforts to reduce air pollution could make a real difference for the environment and human health.

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Even low levels of air pollution may quietly scar your heart, MRI study finds

Is the air you breathe silently fueling dementia? A 29-million-person study says yes

Photo, posted February 25, 2017, courtesy of CCO Bay via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Seaweed and concrete

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Modern civilization is pretty much made of concrete.  People use more concrete than any other substance apart from water.  But concrete is made from cement, and cement is the source of 10% of all carbon dioxide emissions worldwide.

Researchers at the University of Washington and Microsoft have developed a new kind of concrete made by mixing dried, powdered seaweed with cement.  By fortifying cement with seaweed, the global warming potential of the concrete is reduced by 21% without weakening it. 

This novel recipe for concrete was developed using machine learning models, arriving upon it in a fraction of the time it would have taken by traditional experimentation.

Producing cement leads to carbon emissions from the fossil fuels used to heat raw materials and from a chemical reaction called calcination that occurs during the production process.  Seaweed is a carbon sink that pulls carbon dioxide out of the air and stores it while it grows.  By replacing some of cement in concrete, the resultant product has a much smaller carbon footprint.

Machine learning was used to predict the ideal mixture of cement and seaweed to yield concrete with a reduced carbon footprint that still passed mechanical strength tests.  Finding the right mixture would have taken 5 years ordinarily, but the machine learning process took only 28 days.

The researchers plan to generalize their work to different kinds of algae and even to food waste or other natural materials in order to create local, sustainable cement alternatives around the world. 

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Seaweed-infused cement could cut concrete’s carbon footprint

Photo, posted June 29, 2009, courtesy of Peter Castleton via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Facemask pollution

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During the height of the Covid-19 pandemic, the global usage of disposable facemasks reached a staggering 129 billion per month. Most of these masks are manufactured from petroleum-based non-renewable plastics like polypropylene and the disposal of these masks results in serious pollution problems.  These include the loss of ecological integrity from buried waste in landfills, air pollution from increased waste incineration, and microplastic pollution. 

Recent research by engineers at Washington University in St. Louis investigated the multipronged pollution problem brought about by discarded facemasks.  The study in particular looked at the chemical changes that occur when facemasks are exposed to sunlight, water, and trace metal ions.

Masks littering the environment degrade into nanoplastics and produce reactive oxygen species.  These chemical agents interact with trace metal ions in the environment within hours.  The result is oxides of metals like manganese and iron, which can drive various biogeochemical reactions.

Abandoning and forgetting about plastics like facemasks is an unsustainable practice.  Plastics not only cause physical damage, but also introduce unpredictable and potentially dangerous chemical changes into environmental systems.

Plastic waste is a global problem that has continued to grow and become an increasingly serious threat over decades.  Understanding the nature of the effects of billions of facemasks in the environment is essential to efforts to address the challenges created by them.

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Sun exposure changes chemical fate of littered face masks

Photo, posted August 21, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Better blue LEDs

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LEDs have become the standard source of energy-efficient lighting.  They make use of semiconductors to turn electricity into light.  Depending upon the materials used to make them, LEDs produce different colors.  In the early 1990s, the first blue LEDs were discovered, ultimately earning the Nobel Prize in physics, and enabling LEDs to produce white light, which is essential for general lighting applications.

Blue LEDs have shortcomings.  Some have issues with stability, scalability, cost, efficiency, complexity in manufacturing, or have environmental concerns because of the use of toxic components. 

Researchers at Rutgers University in collaboration with scientists at several other institutions have found a way to make blue LEDs more efficient and sustainable.  These LEDs use a new type of hybrid material that is a combination of copper iodide with organic molecules.  The impressive performance of these LEDs was achieved through an innovative technique called dual interfacial hydrogen-bond passivation.  This new manufacturing technique boosts the performance of LEDs by a factor of four.

The material has several advantages.  It has a very high photoluminescence quantum yield, which means that it converts nearly all the photoenergy it receives into blue light.  The LEDs last longer than many others and they work well in larger-scale applications, maintaining high efficiency.  The materials are eco-friendly and cost-effective.

According to the researchers, this new approach could be a versatile strategy for generating high-performance LEDs that can pave the way for better, brighter, and longer-lasting LEDs.

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Scientists Develop Deep-Blue LEDs Expected to Greatly Enhance General Lighting

Photo, posted February 1, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

An anti-malaria breakthrough

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The deadliest animal in the world is the mosquito.  Mosquitos infected 263 million people with malaria in 2023, leading to 600,000 deaths, 80% of which were children.  Malaria is caused by infection from Plasmodium parasites.  The parasites are transmitted to humans from the bite of infected female mosquitos.

Researchers at the University of California San Diego, Johns Hopkins University, UC Berkeley, and the University of Sāo Paulo have developed a new method that genetically blocks mosquitos from transmitting malaria.

The study was published in the journal Nature.  They used gene editing to change a single molecule within mosquitos.  The genetically altered mosquitos can still bite people with malaria and can still acquire parasites from their blood, but the parasites can no longer be spread to other people.  The switching of one specific amino acid known as L224 with a genetic alternative called Q224 prevents malarial parasites from reaching the salivary glands of the mosquito, thereby preventing the spread of infection.  In extensive tests, the researchers found that while the genetic switch disrupted the parasite’s infection capabilities, the mosquitos’ normal growth and reproduction remained unchanged.

The hope is that the replacement of a single amino acid in mosquitoes that prevents them from being infected with malarial parasites is a beneficial trait that can spread throughout a mosquito population.  The researchers believe that the trait can be spread across diverse mosquito species and populations and can pave the way for adaptable, real-world strategies to control malaria.

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Stealth Genetic Switch in Mosquitoes Halts Malaria Spread

Photo, posted June 20, 2014, courtesy of John Tann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)