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Making wind turbines safer for birds

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There are people who oppose the installation of wind turbines for a variety of reasons. It is true that wind turbines can be dangerous to birds.  Estimates are that about 250,000 birds are killed flying into wind turbines each year in the U.S.  

However, this data needs to be looked at in comparison to bird deaths from flying into electrical lines (25 million), vehicles (214 million), and building glass (at least 600 million). And even these figures pale in comparison to the more than 2 billion birds killed by domestic cats each year.

Despite these facts, it would still be great if fewer birds died from flying into wind turbines.  Researchers at Oregon State University are part of a team looking at reducing bird collision risks from wind turbines by painting a single blade of the turbine black.

Recent research in Norway found that painting a single turbine blade black reduced the number of bird collisions by nearly 72%.  Why should this work?  The hypothesis is that the black-painted blades disrupt the visual uniformity of the airspace around the turbines and makes them more noticeable to birds, which prompts avoidance behavior.

The Norwegian data is based on a relatively small sample size and the Oregon State researchers as well as others in Spain, Sweden, and South Africa are working on more rigorous and comprehensive studies.

The hope is that this rather simple strategy could make windfarms safer for birds.  Unfortunately, this approach is not likely to be very effective with bats, which rely more on auditory cues rather than visual cues.

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Scientists studying impact of painting wind turbine blade black to reduce bird collisions

Photo, posted May 21, 2024, courtesy of Roy Harryman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Declining pollinator populations

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Scientists have been sounding the alarm on the global struggle of pollinators for decades.  Many recent studies have highlighted alarming declines in pollinator populations, sparking concern about the potential negative impacts on ecosystems and agriculture.  Habitat loss, invasive species, and climate change are some of the factors linked to the population declines. But most pollinator research has focused on well-studied species in easily-accessible regions.

In a new study recently published in the journal PLOS One, a research team led by Northern Arizona University compiled data on four major families of bees and butterflies to create species distribution models, allowing them to assess changes over time and space across North America.

The researchers confirmed that bee and butterfly populations are declining in major regions of North America due to ongoing environmental changes, and found that significant gaps in pollinator research limit the ability to protect these species. 

The highest species richness was found along North America’s West Coast –  especially in California. But the models showed a decline in species richness over the past century in western North America.  In contrast, the research team found disproportionate increases in eastern North America.

Comparisons with climate data indicate that the pollinator population changes are at least partly due to the impacts of climate change, including prolonged drought and habitat degradation. 

The study identifies regions of declining populations where officials can prioritize conservation efforts, and highlights how improved monitoring methods could address the knowledge gaps on pollinator populations.

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Bee and butterfly records indicate diversity losses in western and southern North America, but extensive knowledge gaps remain

Bees and butterflies on the decline in western and southern North America

Photo, posted April 3, 2017, courtesy of Tracie Hall via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Where not to plant trees

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Planting huge numbers of trees is often proposed as a way to reduce the severity of climate change.  Studies have looked at the potential for Earth‘s ecosystems to support large additional areas of forest and have found that it would be possible to have at least 25% more forested area than we do now.  This in turn could capture large amounts of carbon and substantially reduce the amount in the atmosphere.

A recent study by researchers at Clark University in Massachusetts and The Nature Conservancy mapped the climate impact of tree planting across the globe, identifying where it would be most and also least beneficial.  The study, published in Nature Communications, found that trees planted in arid, desert regions or in snowy places like the Arctic would, on balance, worsen warming rather than reduce it.

Trees take up carbon dioxide from the atmosphere, which helps to keep warming in check.  But trees with dark, green leaves also absorb heat from sunlight.   Snow and desert sand, on the other hand, are light-colored and reflect more sunlight back into space.  For this reason, trees planted in snowy areas or in the desert will absorb more sunlight than their surroundings.  This can negate the climate benefits of soaking up carbon dioxide.

Previous studies only looked at how much carbon dioxide would be removed by planting trees in order to determine how much warming would be prevented.  The new study finds that it matters where the trees are planted.

Fortunately, the new study also shows that tree planting projects that are currently underway or that are in the pipeline are largely concentrated in regions where they will indeed help slow global warming.

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This Map Shows Where Planting Trees Would Make Climate Change Worse

Photo, posted April 5, 2022, courtesy of UC Davis Arboretum and Public Garden via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastics In The Air | Earth Wise

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Plastic pollution is a big deal.  There are plastics clogging up landfills and waterways and accumulating in the oceans, choking turtles and seabirds.  Annual production of plastics has grown from 2 million tons a year in 1950 to more than 450 million tons today.

As if plastic problems weren’t already big enough, it is becoming increasingly clear that there are growing amounts of microplastic particles in the air. Bits of plastic are lofted into the sky from seafoam bubbles and from spinning tires on highways.  The particles are so light that they can travel for thousands of miles, far from where they originate.

Studies in recent years documented the presence of plastic particles even in places like the Pyrenees in Europe and in federally protected areas of the US.  Other studies have measured the quantity of plastic in the air of various locations and have looked at the origins of the particles.

In the western US, over 80% of microplastics came from roads where vehicles kick up particles from tires and brakes.   In remote areas of the Pacific, there is less than a single particle of plastic per cubic meter of air.  In cities like London and Beijing, on the other hand, there can be several thousand particles per cubic meter.

Microplastics can act as airborne aerosols, like dust, salt, soot, volcanic ash, and other particles.  Aerosols play an important role in the formation of clouds and in temperature regulation on the earth.  At low concentrations, such as exist in most places, microplastic aerosols don’t have much of an effect.  But there are more in the atmosphere all the time and, at this point, scientists don’t really know what effect they will have.

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Microplastics Are Filling the Skies. Will They Affect the Climate?

Photo, posted August 28, 2014, courtesy of Alan Levine via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Harvesting Water From The Air | Earth Wise

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Engineers at MIT have created a superabsorbent material that can soak up significant amounts of moisture from the air, even in desert-like conditions.

The material is a transparent, rubbery substance made from hydrogel, which is a naturally absorbent material that is already widely used in disposable diapers.  The MIT researchers enhanced the absorbency of hydrogel by infusing it with lithium chloride, which is a type of salt that is a powerful desiccant.

They found that they could infuse hydrogel with more salt than was possible in previous studies.  Earlier studies soaked hydrogels in salty water and waited 24 to 48 hours for the salt to infuse into the gels.  Not much salt ended up in the gels and the material’s ability to absorb water vapor didn’t change much.  In contrast, the MIT researchers let the hydrogels soak up the salt for 30 days and found that far more salt was absorbed into the gel.  The result was that the salt-laden gel could then absorb and retain unprecedented amounts of moisture, even under very dry conditions.

Under very dry conditions of 30% relative humidity, the gels captured 1.79 grams of water per gram of material.  Deserts at night have those levels of relative humidity, so the material is capable of generating water in the desert.

The new material can be made quickly and at large scale.  It could be used as a passive water harvester, particularly in desert and drought-prone regions.  It could continuously absorb water vapor from the air which could then be condensed into drinking water.  The material could also be used in air conditioners as an energy-saving, dehumidifying element.

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This salty gel could harvest water from desert air

Photo, posted July 26, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Enormous Cost Of Steel Corrosion | Earth Wise

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Global steel production has been rising for decades.  Because steel corrodes over time, part of the demand for more steel comes from the need to replace the steel used in construction materials – in everything from bridges to cars – that has become corroded over time.  Studies have estimated that the economic cost of corrosion is an astonishing 3 to 4% of a nation’s gross domestic product.  Globally, this means that steel corrosion costs the world trillions – yes, trillions with a T – of dollars each year.

On top of the staggering economic impact of corrosion, there is the fact that steel production is one of the largest greenhouse gas emitters of any industry, accounting for more than 25% of all manufacturing sector carbon emissions.  In fact, steel manufacturing causes over 10% of total global carbon emissions.  

As a result of regulations placed on the steel industry, technological advances in the steelmaking process have resulted in a 61% reduction in the industry’s energy consumption over the last 50 years.   There are continuing efforts to reduce the energy consumption of steel making and to move away from the use of fossil fuels to produce the needed energy.  But without significant improvements, just the emissions associated with replacing corroded steel could make the goals set by the Paris Climate Agreement unfeasible.

It’s hard to believe that something costing the world trillions of dollars and has a major negative impact on the climate is largely invisible.  Steel corrosion is an enormous societal challenge that has gone under the  radar for decades and therefore has not received anything like the attention it deserves.

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Reducing steel corrosion vital to combating climate change

Photo, posted July 24, 2008, courtesy of Phil Whitehouse via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

City Greenery And Carbon Emissions | Earth Wise

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According to the United Nations, more than half of the world’s population currently lives in cities.  Projections show that the combination of urbanization and global population growth could add another 2.5 billion people to cities by 2050. 

Unsurprisingly, cities are a major contributor to climate change.  According to U.N. estimates, cities are responsible for 75% of global carbon dioxide emissions, with transportation and buildings being among the largest contributors. 

According to a new study of vegetation across New York City and some adjoining urban areas, photosynthesis by trees and grasses on many summer days absorbs all the carbon emissions produced by cars, trucks and buses, and then some.  In fact, on many summer days, the total carbon uptake in the region equaled up to 40% of a summer afternoon’s total emissions from all sources in the City. The results, which were recently published in the journal Environmental Research Letters, further highlights the critical importance of urban greenery.

Most previous studies have analyzed the carbon uptake of vegetation by looking at the contiguous tracts of green spaces, but this only comprises about 10% of metro areas.  Using detailed aerial radar imagery of New York City that mapped vegetation in unprecedented 6-inch grids, the researchers were able to include the other 90% of the metro area typically left out in most models. 

Since carbon uptake by vegetation only occurs during the growing season, green spaces in cities situated in warmer climates likely play a larger role in carbon uptake. 

As city populations swell around the world, every bit of urban greenery is critical in the fight against climate change. 

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New York City’s greenery absorbs a surprising amount of its carbon emissions

68% of the world population projected to live in urban areas by 2050, says UN

Photo, posted October 5, 2009, courtesy of David Orban via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

2022 Temperature Report | Earth Wise

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The average surface temperature for the Earth in 2022 tied with 2015 as the fifth warmest on record.  The warming trend for the planet continued with global temperatures 1.6 degrees Fahrenheit above the average baseline for 1951-1980 that NASA uses for its studies. Compared with the late 19th century average used in setting climate goals, global temperatures are up about 1.1 degrees Celsius, or 2 degrees Fahrenheit.

Overall, the past nine years have been the warmest since modern recordkeeping began in 1880.   The rising temperatures have moved in concert with rising levels of greenhouse gases entering the atmosphere from human activity.  Many factors can affect the average temperature in any given year including El Nino and La Nina conditions in the Pacific.  But the longer-term trend is quite clear.  Global temperatures continue to rise.

Greenhouse gas emissions have reached all-time high levels despite increasing efforts to reduce them.  There was a real drop in levels in 2020 due to reduced activity during COVID-19 lockdowns, but they rebounded soon thereafter. 

The Arctic region continues to experience the strongest warming trends, as much as four times the global average.  Arctic warming has a major impact on weather at lower latitudes as it changes the behavior of the jet stream as well as affecting ocean currents and water temperatures.

As global temperatures continue to rise, rainfall and tropical storms have become more intense, droughts have become more severe, and ocean storm surges have had increasing impact.  From torrential monsoons in Asia to megadroughts in the U.S. Southwest, extreme weather has become the new normal.

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NASA Says 2022 Fifth Warmest Year on Record, Warming Trend Continues

Photo, posted June 20, 2020, courtesy of Daxis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Carbon Footprint Of Electric Vehicles | Earth Wise

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Electric vehicles are widely known to be the environmentally friendly alternative to internal combustion-based cars.   But there are skeptics who argue that EVs actually have a larger carbon footprint than nonelectric vehicles.  The argument is that the manufacturing and disposal of vehicle batteries is very carbon intensive.  They also point to the reliance on coal to produce the electricity that powers the cars.

These claims have led to multiple studies in the form of life-cycle analyses comparing the amount of greenhouse gases created by the production, use, and disposal of a battery electric vehicle to that associated with a gasoline-powered car of a similar size.

In short, the studies have found that while it is true that the production of a battery electric vehicle results in more emissions than a gasoline-powered one, this difference disappears as the vehicle is driven. 

According to a study conducted by the University of Michigan and financed by the Ford Motor Company, the emissions equation evens out in 1.4-1.5 years for sedans, 1.6-1.9 years for S.U.V.s, and about 1.6 years for pickup trucks.

Emissions from driving come from burning gas in the nonelectric vehicles and from the generation of electricity used by the battery-powered cars.  In the current average power mix across the U.S., driving an EV results in a 35% reduction in emissions.  However, it varies tremendously by location.  There are some places with very dirty power and some with very clean power.  But of the more than 3,000 counties in the U.S., only 78 end up with higher emissions from electric cars.  Of course, as the electric grid gets greener, the advantages of electric cars only become greater.

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E.V.s Start With a Bigger Carbon Footprint. But That Doesn’t Last.

Photo, posted May 21, 2022, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Cleaning Up Forever Chemicals | Earth Wise

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PFAS, per- and polyfluoroalkyl substances, are chemical pollutants that threaten human health and ecosystem sustainability.  They are used in a wide range of applications including food wrappers and packaging, dental floss, firefighting foam, nonstick cookware, textiles, and electronics.  Over decades, these manufactured chemicals have leached into our soil, air, and water.  Chemical bonds in PFAS molecules are some of the strongest known, so the substances do not degrade easily in the environment.

Studies have shown that at certain levels, PFAS chemicals can be harmful to humans and wildlife and have been associated with a wide variety of health problems.

Currently, the primary way to dispose of PFAS chemicals is to burn them, which is an expensive multistep process.  Even trace levels are toxic, so when they occur in water in low amounts, they need to be concentrated in order to be destroyed.

Researchers at Texas A&M University have developed a novel bioremediation technology for cleaning up PFAS.  It uses a plant-derived material to absorb the PFAS which is then eliminated by microbial fungi that literally eat the forever chemicals.

The sustainable plant material serves as a framework to adsorb the PFAS.  That material containing the adsorbed PFAS serves as food for the fungus.  Once the fungus has eaten it, the PFAS is gone. 

The EPA has established a nationwide program to monitor the occurrence and levels of PFAS in public water systems and is considering adding PFAS threshold levels to drinking water standards.  If this happens, the technology developed at Texas A&M may become an essential part of municipal water systems.

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Texas A&M AgriLife develops new bioremediation material to clean up ‘forever chemicals’

Photo, posted August 10, 2013, courtesy of Mike Mozart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bidding ‘Adieu’ To Single-Use Plastics | Earth Wise

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Since the 1950s, more than nine billion tons of plastic have been produced, and 50% of that has been during the past 15 years.  While there are some use cases for plastic that are important, it generally serves as the poster child of our throwaway culture.

Plastic pollution can be found everywhere on earth, from the top of the tallest mountains to the bottom of the deepest oceans.  It’s in our food, water, and air. 

By 2040, researchers predict that there will be nearly 90 million tons of plastic pollution entering the environment each year.  By some estimates, single-use plastics account for half of all our plastic waste.    

Many cities, states, and even countries are limiting or even banning single-use plastics.  Canada recently announced a ban on single-use plastics.  The ban includes things like plastic shopping bags, cups, cutlery, straws, stirrers, and take-out food containers.

The ban will phase in over the next several years, beginning with a ban on the manufacture and import of single-use plastics by the end of this year.  Sales of these items will be prohibited in 2023, and the export of plastics will cease by the end of 2025.  

Canada’s southern neighbor, the United States, leads the world in plastic waste generation.  While some states have approved single-use plastic reforms, most of the effort at the federal level has focused on improving recycling rates.  However, a recent report from several environmental organizations found that plastic recycling rates in the U.S. have actually declined in the last several years, from an already-dismal 8.7% to less than 6%.    

Suggesting the plastic waste problem can be solved with improved recycling rates is greenwashing the issue. 

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Canada is banning single-use plastics, including grocery bags and straws

Photo, posted October 31, 2011, courtesy of Mara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Feeding Cows Seaweed | Earth Wise

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When cows digest their food, they burp, and when they burp, they release methane.  This is called enteric methane and it’s a real problem.  A single cow belches out 220 pounds of methane each year, which is the greenhouse gas equivalent of burning over 900 gallons of gasoline.  That’s more than the average car uses in a year.

Several studies have shown that feeding cows seaweed has the potential to substantially reduce the amount of methane in cow burps.  The latest comes from a trial that took place at the Straus Family Creamery, an organic dairy producer in Marin County, California.

The trial used a new seaweed-derived feed additive called Brominata.  Brominata is made of a red seaweed called Asparagopsis taxiformis.  The addition of the seaweed to the cows’ diets on the Straus farm resulted in an 52% average reduction in enteric methane emissions.  One cow in the study showed a reduction of 92%.

Cutting enteric methane emissions in half would be a huge improvement that would be quite difficult to achieve by convincing enough people to reduce meat and dairy consumption.

The California Air Resources Board has identified feed additives as an emissions-reduction strategy for the dairy industry.  There are now some synthetic feed additives that have been developed that reduce enteric methane, but they haven’tyet  received FDA approval for use in the U.S.  Brominata has been approved as Generally Regarded as Safe by the California Food and Drug Administration.  Whether it and similar seaweed-based feeds can be produced in sufficient quantity and without adverse environmental effects remains to be seen.  But it is an intriguing approach to solving a complicated problem.

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Feeding Cows Seaweed Reduces Their Methane Emissions, but California Farms Are a Long Way From Scaling Up the Practice

Photo, posted November 10, 2015, courtesy of Lance Cheung/USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Houseplants And Indoor Air Quality | Earth Wise

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Many of us have houseplants in our homes and offices.  The foliage and flowers add beauty and comfort to our indoor spaces.  But it turns out that there are health advantages as well.

Many studies have demonstrated that indoor houseplants can help keep you happier and healthier by improving your mood, reducing fatigue, lowering stress and anxiety, and improving focus.  Houseplants can also improve indoor air quality.

According to a new study by researchers from the University of Birmingham in the U.K. in partnership with the Royal Horticultural Society, ordinary houseplants can potentially make a significant contribution to reducing indoor air pollution.

The researchers tested three types of houseplants commonly found in homes in the U.K: Peace lily, corn plant, and fern arum.  These plants are easy to maintain and not overly expensive. 

In the study, the research team exposed these houseplants to nitrogen dioxide, which is a common indoor pollutant.  The plants were isolated in a test chamber containing levels of nitrogen dioxide comparable to what might be in an office situated next to a busy road.  The researchers found that all the plants were able to remove about half of the nitrogen dioxide in the chamber in just one hour.    

In a poorly ventilated small office with high levels of air pollution, the researchers calculated that five houseplants would remove up to 20% of the nitrogen dioxide.  In a larger space, the effect would be smaller – around 3.5% – although this figure could be increased by adding more plants.

Bringing nature indoors is one way to breathe cleaner air.

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Common houseplants can improve air quality indoors

Reducing air pollution with plants

Photo, posted September 21, 2014, courtesy of Olin Gilbert via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A New “Wonder Material” | Earth Wise

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Graphene is a form of carbon made of single-atom-thick layers. It has many remarkable properties and researchers around the world continue to investigate its use in multiple applications.

In 2019, a new material composed of single-atom-thick layers was produced for the first time.  It is phosphorene nanoribbons or PNRs, which are ribbon-like strands of two-dimensional phosphorous.  These materials are tiny ribbons that can be a single atomic layer thick and less than 100 atoms wide but millions of atoms long.  They are comparable in aspect ratio to the cables that span the Golden Gate Bridge.   Theoretical studies have predicted how PNR properties could benefit all sorts of devices, including batteries, biomedical sensors, thermoelectric devices, nanoelectronics, and quantum computers. 

As an example, nanoribbons have great potential to create faster-charging batteries because they can hold more ions than can be stored in conventional battery materials.

Recently, for the first time, a team of researchers led by Imperial College London and University College London researchers has used PNRs to significantly improve the efficiency of a device.  The device is a new kind of solar cell, and it represents the first demonstration that this new wonder material might actually live up to its hype.

The researchers incorporated PNRs into solar cells made from perovskites.  The resultant devices had an efficiency above 21%, which is comparable to traditional silicon solar cells.  Apart from the measured results, the team was able to experimentally verify the mechanism by which the PNRs enhanced the improved efficiency.

Further studies using PNRs in devices will allow researchers to discover more mechanisms for how they can improve performance.

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‘Wonder material’ phosphorene nanoribbons live up to hype in first demonstration

Photo, posted October 6, 2010, courtesy of Alexander AlUS / CORE-Materials via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Pacific Northwest Heatwave | Earth Wise

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The late-June heatwave in the Pacific Northwest shattered temperature records in dozens of locations.  Cities like Portland and Seattle saw historic high temperatures and one town in British Columbia saw temperatures hotter than ever recorded in Las Vegas.

An international team of weather and climate experts analyzed this extreme weather event and came to a preliminary conclusion that it was a 1-in-1000-year event in today’s climate.  “Today’s climate” means the already warmer conditions that the world is experiencing as a result of the changing climate.

If that analysis is accurate, then such an extreme temperature event would have been at least 150 times rarer in the era before global warming.  In other words, they concluded that it would have been a 1-in-150,000-year event, which means that it would have been virtually impossible in pre-industrial times.

Given that they estimated that the extreme temperatures were a 1-in-1000-year event at this point, it would follow that such events are not about to become commonplace any time soon.  On the face of it, that is somewhat comforting to hear.

However, all of this assumes that global warming will not radically change the statistical distribution of global temperatures.  If that assumption fails to hold, then all bets are off.  Perhaps temperatures like those experienced in the Pacific Northwest might be a 1-in-50-year event, for example, but we just don’t realize it yet.  Follow-up studies will be looking for evidence of significant changes in the distribution of weather events.  For now, a 1-in-1000-year event means there is only a 0.1% chance of occurring in a given year.  That’s good news for the residents of that region.

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Preliminary analysis concludes Pacific Northwest heat wave was a 1,000-year event…hopefully

Photo, posted June 4, 2016, courtesy of Jody Claborn via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rising Seas In The Maldives | Earth Wise

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The Republic of Maldives is an archipelago in the Indian Ocean, southwest of Sri Lanka and India and about 400 miles from the Asian mainland.  It is one of the world’s most geographically dispersed sovereign states, the smallest Asian country by land area, and, with a little over 500,000 inhabitants, the second least populous country in Asia.  With its spectacular scenic beauty, it is also a premier tourist attraction.

With more than 80% of its 1,190 coral islands standing less than 1 meter above sea level, the Maldives has the lowest terrain of any country in the world.  As a result, the Maldives is particularly vulnerable to the sea level rise associated with climate change.

Some studies predict a grim future for the Maldives as well as other low-lying islands.  One study concluded that the islands could become uninhabitable by 2050 as wave-driven flooding becomes more common and freshwater becomes limited.

The Maldives government has explored plans to purchase land on higher ground in other countries.  Planners are also working to enhance the resilience of the country’s current islands.   An example is Hulhumalé, a newly constructed artificial island northeast of the country’s capital, Malé.

Construction of Hulhumalé began in 1997 and it now covers 1.5 square miles, making it the fourth largest island in the Maldives.  Its population is now more than 50,000, with more than 200,000 expected to eventually move there.  The new island, built by pumping sand from the seafloor onto a coral platform, rises about 2 meters above sea level.  The extra height could make the new island a refuge for Maldivians driven off lower-lying islands by the rising seas.

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Preparing for Rising Seas in the Maldives

Photo, posted June 15, 2009, courtesy of Elena N via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Silent Killer | Earth Wise

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Air pollution is deadly.  Studies have found that particles from air pollution can enter our lungs and bloodstream, contributing to major health conditions including heart disease, stroke, cancer, and kidney disease.  Globally, air pollution is responsible for the premature deaths of millions of people every year. 

The first line of defense against air pollution is ambient air quality standards.  But according to researchers from McGill University, more than half of the world’s population lives without the protection of adequate air quality standards.

The research team focused on a specific type of air pollution called particulate matter 2.5 (more commonly called PM2.5).  PM2.5 refers to tiny particles or droplets in the air that are two and one half microns or less in width.  These tiny particles are responsible for an estimated 4.2 million premature deaths every year globally, including more than one million deaths in China, nearly 200,000 in Europe, and more than 50,000 in the United States.

In the study, which was recently published in the Bulletin of the World Health Organization, the researchers found that where there are air quality protections, the standards are often worse than what the WHO considers safe.  Some regions with high air pollution levels, like the Middle East, don’t even measure PM2.5 air pollution.  The researchers found that the weakest air quality standards are often violated, while the strictest standards are often met. 

More than half of the world’s population is in urgent need of adequate air quality standards.   

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Air pollution: The silent killer called PM 2.5

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

Earth Wise is a production of WAMC Northeast Public Radio.

Can We Tow Icebergs To Use Their Water? | Earth Wise

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At any given time, there are thousands of icebergs adrift in Antarctica that are hundreds or even thousands of feet across.  For at least fifty years, there has been speculation about whether such icebergs could be towed from the Antarctic to places experiencing freshwater shortages.  The feasibility of such a scheme is still the subject of studies that nowadays include sophisticated computer modeling.

Places like the Persian Gulf, Cape Town, South Africa, and Perth, Australia all experience water shortages and could benefit tremendously from having a large iceberg towed to their waters.

How big an iceberg would it take to quench the thirst of a city like Cape Town?  Computer models show that an iceberg 2,000 feet long and 650 feet thick could produce enough water to supply the city for more than a year.  However, with water temperatures in the 60s in the area, even such a large iceberg would melt away within weeks.  So, to get enough water for a year, it would require a much larger iceberg – one at least a couple of miles long.

Daunting problems include figuring out how many and what sort of ships would be required.  An alternative to such giant icebergs would be finding a way to insulate the icebergs so they don’t melt as quickly, thereby allowing much smaller and more towable icebergs to be harvested.

Beyond these issues, there are the ecological issues of the effects of huge amounts of very cold fresh water affecting local marine ecosystems. 

Despite a wide range of challenges, there is continued interest in the idea of using icebergs as a source of very pure fresh water.  In an increasingly thirsty world, it might someday actually happen.

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Can icebergs be towed to water-starved cities?

Photo, posted November 1, 2007, courtesy of M A Felton via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Artificial Light And Nature | Earth Wise

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Most of us are familiar with air pollution, water pollution, soil pollution, and noise pollution.  But it turns out that light can also be a pollutant as well. 

Light pollution is a consequence of industrial civilization.  Sources of light pollution include building interior and exterior lighting, advertising billboards, factories, commercial properties, streetlights, and sporting venues.      

According to findings in a new report from the University of Exeter, artificial nighttime lighting has a wide range of effects across the natural world and should be limited wherever possible.  The research team analyzed more than 100 studies and found that artificial lighting has widespread impacts on both animals and plants. 

In the study, which was funded by the Natural Environment Research Council in the U.K., researchers consistently found changes to animals’ bodies and behavior as a result of artificial lighting.  In particular, levels of the sleep cycle-regulating hormone melatonin were reduced by exposure to artificial lighting at night in all animal species studied. 

Exposure to artificial nighttime lighting also affected the timing of animals’ activities.  For rodents, which are largely nocturnal, the duration of activity was often reduced by exposure to nighttime lighting.  On the other hand, for diurnal birds, exposure to nighttime lighting led to an extension of the duration of their activities.  

Previous studies have found other wide-ranging impacts of nighttime lighting, from reducing pollination by insects to trees budding earlier in spring.  

Artificial nighttime lighting is human driven and very disruptive to the natural world.  While there’s no off switch for the planet, we could reduce the amount of light pollution drastically with no impact on our lives. 

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Artificial night lighting has widespread impacts on nature

Photo, posted July 29, 2017, courtesy of spacedust2019 via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Do Forests Grow Better With Our Help? | Earth Wise

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Tree planting has become a worldwide cause.  International calls to plant a trillion trees to combat climate change have led to multiple initiatives by countries around the world.  Even the current U.S. administration, with support from businesses and nonprofits has promised to plant over 800 million trees across an estimated 2.8 million acres.  Planting trees is widely seen to be a vital nature-based solution to climate change; a way of moderating its effects as the world works to reduce carbon emissions.  However, recent studies have created some pushback from that view.

The new studies are not opposed to trees.  What they have revealed is that allowing forests to grow back naturally is a better strategy than planting trees.  The new data has shown that, among other things, estimates of the rate of carbon accumulation by natural forest regrowth have on average been 32% too low and, for tropical forests, have been 53% too low.

A new study published in Nature identified 1.67 billion acres that could be set aside to allow trees to regrow.  It excludes land under cultivation or built on, along with various existing valuable ecosystems. 

Natural regrowth allows nature to select which tree species take hold and turns out to happen quite rapidly and in a widespread manner.  The great thing about natural restoration of forests is that it often requires nothing more than human inaction.  Because it requires no policy initiatives, investments, or oversight, data on its extent is rather scarce.  But the data we have reveals that wherever forests have been allowed to recover on their own, it appears to happen rapidly and with great success.

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Natural Debate: Do Forests Grow Better With Our Help or Without?

Photo, posted September 5, 2015, courtesy of Nicholas A. Tonelli 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...)