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Bees and urban wildflowers

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Post-industrial cities often have large numbers of vacant lots, left behind as people have moved out of the area.  Local residents are often tempted to plant wildflowers to make these deserted spaces more attractive. 

Wildflowers are an important food source for bees.  Pollinators like bees play a vital role in food production and attracting them with food sources is a good idea.  However, a study by researchers at the University of Cambridge in the UK found that there are dangers associated with planting wildflowers in some urban settings.

Wildflowers growing on land previously used for buildings and factories can accumulate lead, arsenic, and other metal contaminants from the soil.  These metals have previously been shown to damage the health of pollinators that ingest the metals in the nectar as they feed.

The Cambridge study was carried out in Cleveland, Ohio, which has nearly 34,000 vacant lots.  Cleveland was previously the site of iron and steel production, oil refining, and car manufacturing.  The researchers tested the nectar from flowering plants growing on disused land throughout the city.  Lead was the contaminant found in the highest concentrations.  They also found that different species of plants accumulate different amounts and different types of metals.

The goal of the study was not to discourage the planting of wildflowers in towns and cities.  It is to highlight the importance of growing the right species of wildflowers as well as to encourage testing soils for metals before planting wildflowers and to clean up pollution.  Wildflowers are important for pollinators, but it is also important that they don’t contribute to the decline of pollinator populations that has already been happening for a number of reasons.

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Growing wildflowers on disused urban land can damage bee health

Photo, posted August 26, 2012, courtesy of RJP via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A giant plane for giant wind turbines

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Wind turbines have been getting bigger all the time.  Larger turbines have real advantages.  They can operate at lower speeds so they can be deployed in more places.  They capture more wind, so they make more power.  Large wind turbines can have blades more than 200 feet long and even larger ones are on the way.  An offshore wind farm in China has turbines with 400-foot blades.

Giant wind turbines face a thorny problem:  getting the blades to where they are to be installed.  The enormous blades can’t be easily shipped across aging roads and bridges.   Tunnels are too narrow, bridges are too low, and roads can be too tight to allow turns when transporting these massive turbine parts.  Some developers have actually had to build special roads for wind projects.

For nearly a decade, a Boulder Colorado company called Radia has been working on what would be the world’s largest plane.  The WindRunner aircraft would have a dozen times the cargo volume of a Boeing 747.  The WindRunner will be 356 feet long and 79 feet tall.  While its primary purpose would be transporting wind turbine blades, the plane could also be used to aid the military or businesses that are thinking really big.  Product developers often don’t even try to invent really big things because there is no way to transport them.  Radia expects the WindRunner to be rolled out before the end of the decade.

The wind industry is currently facing strong opposition from the Trump administration, but wind energy is not going away and bigger and better wind turbines will ultimately be built and will have to be transported.

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Building the World’s Biggest Plane to Help Catch the Wind

Photo, October 10, 2013, courtesy of Allan Der via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Vegetation and climate change

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Temperatures have been steadily rising around the world as a result of the increased greenhouse gas emissions from human activities.  This warming trend has led to more frequent and intense heat waves, droughts, and other extreme weather events.  Rising temperatures are also impacting human health, leading to increased risks of heat-related illnesses and a higher number of fatalities during extreme heat events.

One simple but effective way to reduce the health risks from extreme heat is to increase urban vegetation.  According to new research led by scientists from Monash University in Australia, increasing urban vegetation by 30% could save more than one-third of all heat-related deaths.  The study, which was recently published in The Lancet Planetary Health, examined more than 11,000 urban areas and found that increasing greenery could have saved up to 1.16 million lives worldwide between 2000 and 2019.

The impact of increasing urban vegetation on heat-related deaths varies by climate, greenness, socioeconomic, and demographic factors, with the greatest benefits seen in Southern Asia, Eastern Europe, and Eastern Asia. 

Vegetation has a cooling effect on temperature.  Vegetation helps regulate the Earth’s climate by absorbing carbon dioxide during photosynthesis, which helps to reduce greenhouse gases in the atmosphere. Vegetation also cools the environment through shading, moisture release, and evapotranspiration, which reduces temperatures and mitigates heat-related health risks.

Incorporating more vegetation into urban areas is a powerful solution to mitigate the impacts of climate change and protect human health.

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Increasing urban vegetation could have saved over 1.1m lives in two decades

Photo, posted July 1, 2023, courtesy of Lauri via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Modeling geoengineering

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As the impacts of climate change continue to mount up, there is increasing interest in radical intervention measures designed to keep a lid on rising global temperatures.  Such measures are fraught with potential dangers and unintended consequences but there is no guarantee that one or another of them might still be attempted in the future.  Increasing international interest in geoengineering as a potential strategy for mitigating climate change has created a pressing need to consider its impact before any potentially irreversible actions are taken.

The Natural Environment Research Council in the UK is funding four research projects aimed at understanding the potential consequences of solar radiation modification (SRM) being deployed in the real world.

SRM consists of methods to reflect some of the Sun’s radiation back into space instead of allowing it to reach and warm the earth. 

One approach is stratospheric aerosol intervention in which particles such as sulfates are introduced into the upper atmosphere to reflect sunlight thereby producing a dimming effect.   The idea is to mimic the effects of large volcanic eruptions, which naturally send sulfates into the atmosphere.

A second approach is marine cloud brightening, which increases the reflectivity of clouds over the ocean by spraying very small droplets of sea water into the air.  The fine particles of sea salt enhance cloud condensation nuclei, producing more cloud droplets and making clouds more reflective.

The research aims to deliver independent risk analyses to inform policymakers about the potential environmental impacts of SRM.

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Scientists to model the impact of controlling Earth’s temperature by reflecting solar radiation

Photo, posted May 6, 2009, courtesy of Denys Zadorozhnyi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Volcano monitoring

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Researchers at the University of Alaska Fairbanks and the U.S. Geological Survey have developed a radar-based volcano monitoring system.  The purpose is to provide situational awareness of volcano behavior and identify volcanoes that are becoming restless before other more obvious indications like earthquake activity occur.

The system is called VolcSARvatory and makes use of interferometric synthetic aperture radar to detect ground movement changes as small as one centimeter.  It utilizes two or more radar images from satellites taken at different times.  The images are used to create a time series of data from a single location.

The system has been in operation since early 2022 and proved to be valuable in studying the unexpected activity at the long-quiet Mount Edgecumbe volcano near Sitka, Alaska where conventional monitoring was not taking place.

According to the researchers, the technology has evolved to the point where it can be operational at a national level.  The goal is to provide a consistent approach to monitoring active volcanoes.

Volcanoes are not a rare and unlikely source of potential danger in this country.  The volcanoes of Hawaii are the best-known active volcanoes in the United States, but Alaska has about 140 volcanoes that are technically classified as active, with more than 50 that have been active within the past 300 years.  In total, 169 U.S. volcanoes are classified as active including ones in Arizona, California, Colorado, Idaho, Nevada, New Mexico, Oregon, Utah, Washington and Wyoming.

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Alaska-developed volcano monitoring system will expand across U.S.

Photo, posted March 18, 2013, courtesy of Jeffrey Wickett / USFS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

More eco-friendly desalination

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There are about 16,000 operational desalination plants, located across 177 countries, which generate an estimated 25 billion gallons of fresh water daily.

For every gallon of drinking water produced at a typical desalination plant, one and a half gallons of brine are produced.  Much of it is stored in ponds until the water evaporates, leaving behind solid salt or concentrated brine for further treatment.  There are various other techniques for concentrating brines, but they are energy-intensive and environmentally problematic.  The process called electrodialysis uses electrified membranes to concentrate salts. 

Water flows into many channels separated by membranes, each of which has the opposite electrical charge of its neighbors.  Positive salt ions move towards negatively charged electrodes and negative ions move toward positive electrodes.  Two streams result, one containing purified water and one containing concentrated brine.

This eliminates the need for evaporation ponds, but existing electrodialysis membranes either result in leakage of salts into the environment or are too slow, making the process impractical for large-scale use.

Researchers at the University of Michigan have developed a new kind of membrane for electrodialysis.  The new membranes don’t leak and are ten times more conductive than those on the market today which means that they can move more salt using less power.  The membranes can be customized to suit a broad range of water types, which may help make desalination a more sustainable solution to the world’s growing water crisis.

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Making desalination more eco-friendly: New membranes could help eliminate brine waste

Photo, posted February 4, 2012, courtesy of David Martinez Vicente via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Fighting honey fraud

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Honey fraud is a significant issue for the food industry.  What is honey fraud?  Typically, it involves mislabeling where honey was produced or what types of flowers the bees collected nectar from.  Honey made from a single type of flower is often more expensive because of the unique flavor it provides or from potential health benefits.  Sometimes even cheap alternatives like sugar syrups are labelled as honey.  It turns out that honey is one of the most fraud-prone commodities in global trade, with fraud estimated to occur in up to 10% of the honey traded internationally.  Honey from some countries, such as China and India, has had 30% or more of samples found to be fraudulent.

Researchers at McGill University in Montreal have developed an AI-powered method to verify the origin of honey thereby ensuring that what is on the label corresponds to what is in the jar.

The McGill method can determine what kind of flowers the bees visited to produce a particular sample of honey.  Previous honey authentication involved pollen analysis, which is ineffective for honey that was processed or filtered.  The new method uses high-resolution mass spectrometry which captures a unique chemical “fingerprint” from the honey.  Machine learning algorithms read the fingerprint to identify the honey’s origin.

The researchers tested their methodology on a variety of honey samples which they then compared with honey from known botanical sources.  Using previous methods for honey authentication can take days.  The McGill method takes only minutes and works regardless of how the honey was processed.

According to the researchers, people deserve to know that the honey they buy is what it claims to be, and honest honey producers deserve protection from fraudulent competitors.

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Fighting honey fraud with AI technology

Photo, posted May 6, 2012, courtesy of Emma Jane via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Hot water in Boise

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Boise is the capital of Idaho, and the Idaho Statehouse is the only one in the United States to use geothermal heat.  Geothermal heating is possible in Boise because of fault lines that expose its groundwater to hot rocks.  The underground water supply in Boise is heated to around 170 degrees Fahrenheit.  It is the basis of the largest municipally-run geothermal system in the country.

People in Boise began using this natural resource to supply heat to buildings in the 1890s by drilling wells into aquifers that yielded hundreds of thousands of gallons of piping hot water a day.  The water heated pools and public baths, a Victorian mansion, and, eventually, hundreds of homes in what was called the Boise Warm Springs Water District.

The number of buildings that the city of Boise heats with its geothermal resource has grown more than sixfold over the past 40 years.  The water is drawn from wells in the nearby foothills and pumped into a closed-loop network of pipes that reach into buildings.  In each building, the geothermal heat is transferred to water in separate adjoining pipes that distribute the heat throughout the building.  The well water goes back to the aquifer to be heated again.

Today, there are four separately run geothermal water systems in Boise.  One is run by the city, another by the Boise Warm Springs District, and two others that serve the Capitol and Veterans Affairs Buildings.

In 2024, city officials calculated that using geothermal heat reduced annual carbon dioxide emissions by 7,000 tons, the equivalent of removing 1,500 gas-powered cars from the road each year.

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They’re in Hot Water in Idaho. Here’s Why That’s a Good Thing.

Photo, posted May 26, 2010, courtesy of Jason W via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

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

Extreme heat and dairy production

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Climate change is causing more frequent and intense heat waves in the United States. Studies show that not only are heat waves now occurring more often, but that the average heat wave season is nearly 50 days longer now than it was in the 1960s.  The overall rise in temperatures, linked to climate change, has led to increased health risks and fatalities from extreme heat. 

As humans face increasing health risks from this extreme heat, livestock are also suffering from the effects of rising temperatures.  Extreme heat negatively impacts dairy production by causing heat stress in cows, which can reduce milk yield, quality, and the cows’ overall health.

A new study by researchers from the University of Illinois Urbana-Champaign analyzed milk production data from 18,000 dairy farms across nine Midwest states between 2012 and 2016.  The researchers found that high heat and humidity have led to a 1% decline in annual milk yield. While this might not sound like a lot, it amounts to about 1.4 billion pounds of milk over five years from the 18,000 herds included in the study – equivalent to about $245 million in lost revenue.

The study, which was recently published in the journal Food Policy, found that small farms are hit harder than large farms.  Larger farms may be able to mitigate some of the effects through management strategies, such as open barn sides, fans, and sprinklers.

Using projections from 22 different climate models, the research team estimates that more frequent extreme heat will increase milk yield losses by about 30% by 2050. 

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Illinois study: Extreme heat impacts dairy production, small farms most vulnerable

Photo, posted March 13, 2018, courtesy of Gosdin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The problem of mountain lions

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Mountain lions – also known as pumas, cougars, and even sometimes panthers – are the most widely distributed wild land mammal in the world.  They are found from Canada to South America.  There are an estimated 30,000 mountain lions in the United States, mostly in the West, but there are also mountain lions from the Midwest to the East Coast. 

Unlike wolves or grizzly bears, mountain lions are not managed by the federal government; they are managed by states and state regulations vary greatly.  In some places, hunting mountain lions is banned completely; in other places, it is always open season.

As more people encroach on wild land – building homes and small farms, as well as hiking and biking – the numbers of encounters between people and mountain lions are increasing.  And when mountain lions lose their fear of people, there is trouble.

Since 1890, there have been at least 32 fatal mountain lion attacks on humans and more than 170 non-fatal attacks.  California has seen the most attacks in the last 40 years with 22 people injured and four killed.  Despite this, Californians passed a ballot initiative in 1990 that bans all hunting of mountain lions.

There are strategies to reduce habituation and instill fear of humans in mountain lions.  One is called “tree-and-free” that uses dogs to chase mountain lions up trees.  But there are opponents of this and other measures employed. 

The fact is that there are simply too many mountain lions living in close proximity to humans and peaceful coexistence is very difficult to achieve.  Places where hunting lions is permitted have few problems with them, but that is not a solution that is acceptable in many places.  It’s a difficult problem.

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Deadly Encounter: Mountain Lion Attacks Spark Controversy

Photo, posted March 26, 2013, courtesy of the USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Relocating native plants

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Climate change is endangering many native plant species.  As the climate warms, many species will need to establish themselves in new places that are more hospitable than their historic ranges.  But many native plants in the U.S. cannot move themselves by natural forces quickly enough to avoid climate-change driven extinction.  For such plants to survive into the future, they will need human help to move into adjacent areas, a process called “managed relocation.”

Such a process has its problems.  There is no guarantee that a plant will thrive in a new area.  On the other hand, relocating plant species historically has often had disastrous consequences.  Consider, for example, the story of kudzu in the American south.

Researchers at the University of Massachusetts Amherst have studied this problem in detail and reported the results in the journal Global Change Biology.

The issue is how to help plants move successfully without their causing harm in their new locations.  The study found that some plant traits can lead to success and some to ecological disaster.  In some cases, the same traits that help plants to establish themselves in a new location make them powerful invasive species.  Traits like having a large size predispose a plant to not only establish itself but spread wildly. 

The study recommends that people managing relocation need to focus on plants whose traits they have determined to be conducive to successful relocation but more unlikely to cause harm in their new environment. 

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If Native Plants Are Going to Survive Climate Change, They Need Our Help to Move—Here’s How to Do It Safely

Photo, posted August 17, 2012, courtesy of Joshua Mayer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Scrubbers to clean up shipping

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Cargo ships are significant sources of global air pollution because of their fuel oil.  Most ships burn heavy fuel oil that is loaded with sulfur, so when it is burned it produces noxious gases and fine particles that can harm human health and the environment.  The International Maritime Organization enacted a mandatory cap of 0.5% for the sulfur content of marine fuels in 2020.  Heavy fuel oil has a sulfur content of 2 to 3 percent.

Shipping companies can comply by burning low-sulfur fossil fuels or biofuels, but these are much more expensive.  The most feasible and cost-effective option is to install exhaust gas cleaning systems, known as scrubbers. 

A scrubber is a huge metal tank installed in a ship’s exhaust stack.  Seawater is sprayed from nozzles to wash the hot exhaust.  The seawater reacts with sulfur dioxide and converts it to sulfates, which are environmentally benign natural components in seawater.

A study by the National Technical University of Athens in Greece has performed a lifecycle assessment of the use of scrubbers and has found that burning heavy fuel oil with the use of scrubbers can match or even surpass the benefits of using low-sulfur fuels.

Producing low-sulfur fuel causes additional greenhouse gas and particulate matter emissions in refineries. On the other hand, scrubbers reduce sulfur dioxide emissions by 97% and dramatically reduce other pollutants as well.

The study shows the importance of incorporating lifecycle assessments into evaluation of environmental impact reduction policies.

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Study: Burning heavy fuel oil with scrubbers is the best available option for bulk maritime shipping

Photo, posted August 3, 2015, courtesy of Lotsemann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Repurposing used tires

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Every year, millions of tires from cars and trucks end up in landfills.  Just in the U.S., more than 270 million tires were scrapped in 2021 and more than 50 million of them ended up in landfills.  Discarded tires take up huge amounts of space but, more importantly, create environmental hazards.  They leach chemicals into the environment and are a serious fire hazard.

Some tires are chemically recycled via pyrolysis, which is a high-temperature process to decompose the materials in the tire.  But that process introduces harmful byproducts like benzene and dioxins. 

Researchers at the University of North Carolina Chapel Hill have introduced a new chemical method for breaking down rubber waste.  The process transforms discarded rubber into valuable precursors for epoxy resins.

Rubber – either natural rubber or the synthetic kind used in tires – is made of polymers cross-linked together to form a tough, flexible, and durable material.  These very desirable properties make it difficult to break down rubber.

The new research has led to a two-step chemical process that breaks down the rubber into functional materials that be used to produce epoxy resins.  The method does not require extremely high temperatures, uses aqueous media, and takes only six hours.   It represents an efficient, scalable solution for repurposing rubber waste which, even as many other aspects of motor vehicle are changing for the better, remains a continuing environmental problem associated with driving.

This new research marks a significant step towards greener recycling technologies.

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A Cleaner Future for Tires: Scientists Pioneer Chemical Process to Repurpose Rubber Waste

Photo, posted May 5, 2011, courtesy of TireZoo via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Transparent wood

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Plastics are pretty much everywhere in the modern world including places we want them to be and places where we don’t.  Conventional plastics are not biodegradable and instead cause increasing problems wherever they end up after their useful life.  As a result, there are global efforts to find environmentally friendly replacements for petroleum-based plastics.

An interesting candidate for replacing many types of plastic is transparent wood.  Transparent wood is a man-made material derived from natural wood.  Wood has three components:  cellulose, hemicellulose, and lignin.  Transparent wood is created by removing the lignin and hemicellulose, leaving behind a porous, paper-like network of cellulose.  It is transparent but lacks structural strength.  In the past, clear materials like epoxies have been added to produce a strong, transparent material:  transparent wood.  But because of the epoxy – itself a form of plastic – the resultant material was non-biodegradable.

Researchers at Kennesaw State University in Georgia have developed a method for producing transparent wood that replaces epoxies with an egg white and rice extract mixture along with a curing agent called diethylenetriamine.  The end product is a semi-transparent form of wood that is biodegradable. 

The researchers also incorporated silver nanowires into samples of their transparent wood.  This enabled the wood to conduct electricity and could be useful in wearable sensors or as coatings for solar cells.  There is additional research needed to improve the properties of this transparent wood, but a plastic replacement made from natural and inexpensive materials could be quite valuable.

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Making sturdy, semi-transparent wood with cheap, natural materials

Photo, posted August 1, 2017, courtesy of NOAA Marine Debris via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Renewables dominate new global power

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The current administration in the United States is adversarial towards renewable energy and highly supportive of the use of fossil fuels.  Unquestionably, this will create rough waters for the clean energy industry and, unfortunately, will throw a monkey wrench into the world’s efforts to mitigate climate change.  But it cannot stop what has become a powerful global trend.

In the words of U.N. Secretary-General António Guterres: “Renewable energy is powering down the fossil fuel age.”

According to a new report from the International Renewable Energy Agency, renewables accounted for 92% of new power capacity worldwide last year.  Solar is by far the fastest-growing form of renewable power, accounting for 77% of new capacity.

In the U.S., renewables accounted for about 90% of new installed capacity in 2024.  The country added nearly 40 GW of solar power capacity as well as 5 GW of wind power.  Renewables now make up about 30% of the country’s large-scale power generating capacity.  Adding in all carbon-free electricity sources (which include nuclear power), nearly 44% of the country’s electricity was carbon-free.

Headwinds against the growth of renewable energy are getting stronger in the US, but the global trend driven by both economics and environmental concerns is powerful and will continue.  For one thing, in much of the world, solar power is simply the cheapest way to produce electricity and that is pretty difficult to ignore. Global trade wars and economic turmoil will impact renewable energy much as they will other industries, but the long-term trend is clear.

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Renewables Made Up More Than 90 Percent of New Power Installed Globally Last Year

Photo, posted November 23, 2022, courtesy of John Morton 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

The dangers of deep sea mining

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The White House is considering an executive order that would fast-track permitting for deep-sea mining in international waters and allow mining companies to bypass a United Nations-backed review process.

Deep sea mining is the extraction of minerals from the seabed in the deep ocean.  Most of the interest is in what are known as polymetallic nodules, which are potato-sized mineral deposits that have built up in layers over thousands of years. They are located several miles below the surface, primarily in what is called the Clarion-Clipperton zone, which is an environmental management area of the Pacific Ocean about halfway between Mexico and Hawaii.

A new multiyear study led by UK’s National Oceanography Center and published in the journal Nature found that the site of a deep-sea mining test in 1979 still showed lower levels of biodiversity than in neighboring undisturbed sites 44 years later.

Much is not known about the undersea nodules.  We know that they produce oxygen.  If the nodules are removed, will that reduce the amount of oxygen in the deep sea and affect the organisms that live there?  If mining occurs, what effect will the metal-containing sediment plumes churned up by the mining process have? 

The nodule fields sustain highly specialized animal and microbial communities.  More than 20 billion tons of nodules are estimated to lie on the seabed of the Clarion-Clipperton Zone.  If large-scale mining takes place, and there is much interest in that happening, it is important to find out what the impact will be on the ocean and its ecosystems because it is likely to be largely irreversible.

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Deep sea mining for rare metals impacts marine life for decades, scientists say

Photo, posted September 4, 2014, courtesy of James St. John via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A new way to recycle plastic

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Researchers at Northwestern University have developed a new method for recycling plastic that is safer, cleaner, cheaper, and more sustainable than those currently in use.  The U.S. is the world’s largest plastic polluter per capita, and we only recycle 5% of our plastics.  There is a pressing need for better technologies for processing different types of plastic waste.

The Northwestern method is designed to break down polyethylene terephthalate or PET, which is the most common type of polyester plastic.  PET plastic is used in food packaging and beverage bottles and represents 12% of total plastics used globally.  It does not break down easily and is therefore a major contributor to plastic pollution.  It mostly either ends up in landfills or, over time, degrades into tiny microplastics or nanoplastics that end up almost everywhere. 

The non-toxic, environmentally friendly, solvent-free Northwestern process first uses an inexpensive molybdenum catalyst to break apart the bonds in PET.  Then the broken plastic is exposed to ambient air.  Just from the trace amounts of moisture in air, the broken-down PET is converted into monomers, which are the building blocks of plastic.  The monomers could then be recycled back into PET products or used to make other valuable materials.

The process is fast and effective and takes just a few hours.  The catalyst is durable and recyclable, meaning it can be used over and over again.  It only works on polyesters, which means it can be used for recycling mixed plastics without sorting them since it will select only the PET from its inputs.

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Plastic recycling gets a breath of fresh air

Photo, posted August 10, 2013, courtesy of Lisa Risager via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The American butterfly census

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There has been a great deal of interest in the plight of monarch butterflies in this country.  Monarchs’ population and migratory habits are closely watched, and many people have been planting milkweed in their gardens to help their caterpillars.  But other butterfly species have received much less attention despite the fact that many butterfly populations are in decline.

A groundbreaking new study has provided comprehensive answers about the status of butterflies in America.  Over the past 20 years, the contiguous US has lost 22 percent of its butterflies.

The study is based on over 12 million individual butteries counted in 77,000 surveys across 35 monitoring programs from 2000 to 2020.  Three hundred forty-two butterfly species in total were analyzed.  Thirty three percent showed statistically significant declines while less than 3% displayed statistically significant increases.  Overall, 13 times as many species decreased as increased.

Why are butterfly populations crashing?  Experts point to a combination of factors:  habitat loss as land in converted for agriculture or development, climate change, and pesticide use.  It is not clear which factor is most important and may well vary by location.  Pesticide use – especially neonicotinoids – has been shown to play a particularly lethal role in studies. 

Insects including butterflies play a huge role in supporting life on earth.  They pollinate plants, feed birds and many other creatures in the food web.  Nature collapses without them.  And butterflies are clearly in trouble.

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See How Butterflies Are Surviving, or Not, Near You

Photo, posted August 9, 2016, courtesy of Rachel Larue/Arlington National Cemetery 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...)