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Wildfires And Superfund Sites | Earth Wise

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Thousands of contaminated sites exist nationally due to hazardous waste being dumped, left out in the open, or otherwise improperly managed. These sites include manufacturing facilities, processing plants, landfills, and mining sites.  A Congressional act in 1980 established authority by the EPA to ultimately clean up these “Superfund” sites.

According to a government survey last year, 945 Superfund sites are vulnerable to hurricanes, flooding, sea level rise, increased precipitation, or wildfires, all of which are intensifying as the climate warms.   In particular, there are 245 sites vulnerable to wildfires and 68 of them have recently seen wildfires approach.

A comprehensive investigation by Inside Climate News, NBC News, and the Texas Observer has found that the threat presented by wildfires is exceeding authorities’ ability to adequately prepare and respond.  Fires at Superfund sites could release toxins ranging from acid mine drainage to radioactive smoke.

There have already been a number of close calls.  The 2013 Patch Springs Fire near Salt Lake City came within 10 miles of the Tooele Army Depot, a Superfund site with 902 ammunition bunkers along with soil and groundwater contaminated with hazardous chemicals.

The 2018 Carr Fire in Northern California over swept the Iron Mountain Mine Superfund site and threatened to release corrosive chemicals into the watershed.

For sites where no polluter can be made to pay and the EPA lacks cleanup funds, the agency will need to design protections that shield the sites from wildfires as long as the contamination remains. 

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Fueled by Climate Change, Wildfires Threaten Toxic Superfund Sites

Photo, posted July 26, 2018, courtesy of the Bureau of Land Management California via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Heat In The Arctic | Earth Wise

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By mid-November, the Arctic stays dark around the clock and twilight does not return until the end of January.  But even as winter darkness descended upon the Arctic this year, record-breaking high temperatures in the region continued.  In late November, temperatures across the entire Arctic basin were 12 degrees Fahrenheit above normal and some locations saw temperatures as high as 30 degrees above normal.

The entire summer and fall in the Arctic were characterized by exceptionally warm temperatures.  In June, the Siberian town of Verkhoyansk – located north of the Arctic Circle – registered a high temperature of 100.4 degrees.  The refreezing of the Arctic Ocean was greatly delayed this year.  The Northeast Passage along the Siberian Coast remained navigable for a record 112 days before freezing in November, breaking the previous record by more than a month.  The extent of sea ice covering the Arctic Ocean in October was the lowest ever recorded for that month.

The strongest warming occurring in the Arctic is during the fall.  That is because rapidly disappearing sea ice is enabling the dark waters of the Arctic Ocean to absorb heat in the summer and then radiate it back into the atmosphere until late in the fall.  The Arctic region is heating up three times faster than the rest of the planet, which has led to the volume of sea ice decreasing by 2/3 in the past 40 years.

According to researchers, the extreme heat in Siberia this year would have been virtually impossible without human-caused climate change and became 600 times more likely because of human emissions of greenhouse gases.

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Record-shattering Warmth Pushes Arctic Temperatures to 12 Degrees F Above Normal

Photo, posted September 1, 2009, courtesy of the U.S. Geological Survey via Flickr. Photo Credit: Patrick Kelley, U.S. Coast Guard.

Earth Wise is a production of WAMC Northeast Public Radio.

The Search For Lingering Ash | Earth Wise

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Ash trees are some of the most important plants along riverbanks and in wetlands.  There are three ash species in North America:  the white, green, and black ash.  Unfortunately, all three species are critically endangered because of the emerald ash borer.

The emerald ash borer is an exotic beetle from Asia that first showed up in the U.S. in southeastern Michigan in the summer of 2002.  The adult beetles do little damage but the larvae feed on the inner bark of ash trees and disrupt the tree’s ability to transport water and nutrients.  The beetles are now found in 35 states and 5 Canadian provinces and have killed hundreds of millions of ash trees.

The greatest hope for preserving ash tree species relates to lingering ash, which are those rare trees that have managed to survive the onslaught of the emerald ash borer. The idea is that those trees have some natural genetic resistance to the borer.  Getting seeds and cuttings from lingering ash and propagating them at nurseries may be the only way to get ash trees back into the natural landscape.

Lingering ash are extremely rare and therefore very hard to find.  As a result, researchers are reaching out to the public to help with the search and report the presence of these surviving trees in woodlands.

Researchers want to find large, mature trees left among those that were killed by the invasive insect and therefore display great resilience.  In Kentucky, university and Division of Forestry researchers are making use of software tools to engage the assistance of the public. An app called TreeSnap allows people to provide data on trees that they find in their community, on their property, or out in the wild.

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Researchers Ask Public for Help Finding Lingering Ash Trees

Help Our Nation’s Trees!

Photo, posted May 31, 2014, courtesy of Katja Schulz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Global Warming And Sea Turtle Births | Earth Wise

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Climate change is a serious threat to species whose sex is determined by temperature.  Among these are sea turtles.  Whether marine turtles are born male or female turns out to depend on the temperature of their nest during incubation.

Sea turtle nests need to be around 84.6 degrees Fahrenheit on average to produce a 50:50 sex ratio for embryos developing in eggs.  If temperatures are higher, embryos predominantly become female.  There is a transitional range of temperatures over which both males and females are produced.  Below that range, only males are produced; above that range, only females are produced.

According to recent research published in the journal Conservation Science and Practice, sand temperatures along the Red Sea exceeded the 84.6-degree threshold in all but one of the sites studied.  Some sites measured nearly 96 degrees.  The Red Sea region is home to five of the world’s seven species of sea turtles, including endangered green turtles and critically endangered hawksbill turtles.

Skewing the sex distribution of a species is a serious threat to the future survival of the population.

The Red Sea findings are similar to observations around the world.  In Florida, sea turtle hatchlings were born 100% female in seven out the past 10 years, and in the other three years, males only made up 10-20% of the brood.  In Australia’s Raine Island, the largest green turtle nesting ground in the Pacific Ocean, the ratio of female to male turtle hatchlings in 2018 was 116:1.

Marine turtles have been around since the late Triassic period and have adapted to previous climate shifts.  But the rapid pace of human-driven climate change is threatening the future survival of these creatures.

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Rising Temperatures Driving a Shift to All-Female Sea Turtle Populations

Photo, posted in October, 2005, courtesy of Frank_am_Main via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Once In A Lifetime Floods And Climate Change | Earth Wise

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Superstorm Sandy was the deadliest hurricane of 2012 and one of the most destructive hurricanes ever to hit the United States.  According to the National Oceanic and Atmospheric Administration, Superstorm Sandy caused an estimated $74.1 billion dollars in damages.  That figure made it the fourth-costliest storm in U.S. history, trailing only Hurricane Katrina in 2005 and hurricanes Harvey and Maria in 2017.  Superstorm Sandy affected 24 states and all of the eastern seaboard.  

New York was one of the states pummeled by Superstorm Sandy.  The storm brought flood-levels to the region that had not been seen in generations.  But according to a new study published in the journal Climatic Change, those flood levels could become much more common. 

Researchers at Stevens Institute of Technology have found that 100-year and 500-year flood levels could become regular occurrences by the end of the century for the thousands of homes surrounding Jamaica Bay, NY.  The researchers say climate change is the culprit.  

Using anticipated greenhouse gas concentration levels, the research team created simulations to find the probability of different flood levels being reached by the end of the century.  The researchers found that the historical 100-year flood level would become a one-year flood level by the year 2100.  500-year floods, like Superstorm Sandy, would become a four-year flood level by the end of the century. 

While this particular study is specific to Jamaica Bay, it does serve as an example of just how severe and costly the consequences of climate change will be.   

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Once in a lifetime floods to become regular occurrences by end of century

Photo, posted October 29, 2012, courtesy of Rachel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

 

New York And Renewables | Earth Wise

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In 2019, New York generated more electricity from renewable sources than all but three other states.  The 39.4 million MWh of renewable electricity generated in New York was the largest of any state east of the Mississippi. 

New York has been a leader in renewable power long before it became a topic of great interest because of its hydroelectric power.  In 2019, 78% of the state’s renewable electricity came from hydropower.  The Robert Moses Niagara hydroelectric plant is the second-largest capacity conventional hydroelectric power plant in the country. 

The three states that generated more renewable electricity than New York are California, Texas, and Washington.  Washington gets 69% of all its electricity generation from its multiple hydroelectric plants which together produce a quarter of all hydroelectric power in the nation.  Texas leads the nation in wind-powered generation and gets over 17% of its in-state generation from wind.  California gets 14% of its power from solar generation, 7% from wind, and over 16% from its own hydroelectric resources.

Wind is the second-largest source of renewable power in New York, accounting for 11% of renewable generation in the state and 3% of total electricity generation.  Solar power is expanding in New York, but the great majority of it is still in the form of small-scale installations on residential and commercial rooftops.

New York’s renewable generation grew from 19% in 2005 to 30% at present.  New York’s Clean Energy Standard adopted in 2015 requires the state to generate 100% carbon-free electricity by 2040.

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New York generated fourth most electricity from renewables of any state in 2019

Photo, posted October 15, 2010, courtesy of michael-swan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Electronic Waste On The Decline | Earth Wise

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A new study published in the Journal of Industrial Ecology has found that the total mass of electronic waste generated by Americans has been declining since 2015.  Given that electronic devices are playing an ever-growing role in our lives, this finding seems rather surprising.  It also seems like pretty good news, but the underlying facts should dampen our level of enthusiasm.

The main reason for the decline is the disappearance of large, bulky cathode-ray tube televisions and computer monitors.  Since about 10 years ago, CRT displays have been on the decline in the waste stream, thereby leading to an overall decline in total e-waste mass.

Many state regulations with respect to e-waste recycling have targets based on product mass.  The regulations were typically designed to keep electronics with high levels of lead and mercury out of landfills.

At present, the more pertinent concern is how to recover valuable elements like cobalt (from lithium-ion batteries) and indium (from flat-panel displays).  These elements are not so environmentally toxic, but rather are relatively scarce in the earth’s crust. 

The main conclusion to be drawn from the declining mass of electronic waste is not that we are necessarily winning the battle against generating it but rather that e-waste is changing and regulations concerning it need to be rethought.  Focusing regulations on capturing critical elements not only would have significant economic benefits but also would be important in addressing geopolitical uncertainties that potentially could threaten what could be termed the mineral security of the U.S.

E-waste recycling is regulated at the state level and only half the states have e-waste recycling laws.  It may be time for more uniform policies across the country.

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Electronic Waste on the Decline, New Study Finds

Photo, posted January 22, 2013, courtesy of Thorsten Hartmann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

What’s Been Killing Salmon? | Earth Wise

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For decades, there have been mysterious deaths of Coho salmon.  The salmon return from the Pacific Ocean each year to spawn along the West Coast.   They can be found from Alaska all the way down into California.  After heavy rain events each fall, fish have been turning up dead in huge numbers before they spawn.  Normally, less than 1% of adult Coho die before spawning. In these mass death events, anywhere from 40% to 90% of fish can perish in affected streams.  The mysterious phenomenon has been the subject of intense research for years.

Recently, scientists announced that they may have solved the mystery.  There is a chemical antioxidant known as 6PPD that is used in the manufacture of tires around the world to make them last longer.  As tire treads break down over time, they leave behind bits of microplastics on roads.  The 6PPD in the plastic bits reacts with ozone to become another chemical:  a previously unreported substance called 6PPD-quinone.

That chemical turns out to be toxic to Coho salmon.  Researchers have found the presence of 6PPD-quinone in roadway water runoff samples taken from across the West Coast.  Based on these observations, they believe it is likely that exposure to this chemical is the main cause of the Coho salmon population decline.

Coho salmon are a favorite of sport fishermen and have great cultural significance to many Native American tribes on the West Coast.  The central California Coho population is classified as endangered and three other Coho populations are listed as threatened.

Tire industry representatives call the study results “preliminary” but say the industry is deeply committed to protecting the environment.  A safe chemical substitute for 6PPD is clearly needed.

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Salmon have been dying mysteriously on the West Coast for years. Scientists think a chemical in tires may be responsible

Photo, posted November 17, 2011, courtesy of Lynn Ketchum/Oregon State University via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Caribbean Coral Reefs Under Siege | Earth Wise

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Coral reefs around the world have been suffering from warming seas and increasing acidification, both a result of human activity.  In the Caribbean, a new threat has emerged in the form of invasive algae.

New research published in Scientific Reports explains how an aggressive, crust-like alga is overgrowing shallow reefs and taking the place of coral that was damaged by powerful storms that exposed areas of the undersea rock where corals grew. 

Researchers from Oxford University, the Carnegie Institution, and California State University Northridge have been studying these peyssonnelid algal crusts, or PACs, for several years in the U.S. Virgin Islands.  The PAC has been out-competing coral larvae for surface space and then growing over the existing reef architecture, greatly damaging delicate reef ecosystems.

New corals actually prefer to settle on crusty surfaces created by a different type of algae called crustose algae, or CCA.  CCA acts as guideposts for coral larvae by producing biochemical signals as part of a microbial community that entice baby coral to affix itself.

In contrast, the destructive PAC algae exclude coral settlement. The researchers determined that the microbial community associated with PAC algae is deployed to deter grazing from fish and other marine creatures.  Unfortunately, it also deters coral.

Fragile coral ecosystems are already under assault by environmental pollution and global warming.  Now, in the aftermath of powerful hurricanes like Irma and Maria, algal crusts are taking over reef communities and posing an existential threat to Caribbean corals.

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An unusual microbiome characterises a spatially-aggressive crustose alga rapidly overgrowing shallow Caribbean reefs

Photo, posted January 11, 2015, courtesy of Falco Ermert via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recyclable Wind Turbines | Earth Wise

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The blades of modern wind turbines can be longer than the wing of a Boeing 747. Their useful lifetime is perhaps 20 years and after that, they can’t just be hauled away.  They end up being cut up with special industrial saws to create pieces small enough to be strapped to a tractor-trailer.  Then, they end up in landfills.  There are thousands of blades being removed each year and those numbers are growing.

Wind turbine blades are currently manufactured using thermoset resin, which cannot be recycled.  It is also energy-intensive and manpower-intensive to produce.

Researchers at the National Renewable Energy Laboratory in partnership with Arkema Inc of Pennsylvania have demonstrated the feasibility of using thermoplastic resin instead to make wind turbine blades.  That material can be recycled and can also enable longer, lighter-weight, and lower-cost blades.  Using thermoplastic could also allow manufacturers to build blades on site, alleviating the problems of transporting ever larger turbine blades.

Current blades are made primarily of composite materials like fiberglass infused with thermoset resin.  The manufacturing process requires additional heat to cure the resin, which adds cost and time.  Thermoplastic resin cures at room temperature and requires less labor.  With regard to recycling, thermoplastic resin, when heated above a certain temperature, melts into its original liquid resin and can be reused. 

NREL has demonstrated the feasibility of the thermoplastic resin system by manufacturing nearly identical blades using both the standard materials and the thermoplastics.  NREL has also developed a technoeconomic model to evaluate the cost benefits of using thermoplastic resin.

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News Release: NREL Advanced Manufacturing Research Moves Wind Turbine Blades Toward Recyclability

Photo, posted June 28, 2008, courtesy of Patrick Finnegan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Improved Radar For Cars | Earth Wise

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Self-driving cars require a variety of sensor systems in order for the cars to safely navigate roads and deal with the wide range of objects and conditions that they encounter.  Two competing technologies that cars use to identify and locate objects on the scene are radar and LiDAR. 

Radar uses transmitted radio waves to locate objects and LiDAR bounces laser beams off of objects.   Each has its shortcomings.   Radar has the problem that only a small fraction of the transmitted signals gets reflected back to the sensor, so that there is frequently insufficient data to fully characterize a scene.  LiDAR has the problem that it is an optical system that does not work well in fog, dust, rain, or snow.  It is also much more expensive than radar.

Researchers at the University of California San Diego have developed a new system that they describe as a LiDAR-like radar. The system consists of two radar sensors placed on a car’s hood and spaced about 1.5 meters apart.  This configuration enables the system to see more space and detail than a single radar sensor.

Having two radars at different vantage points with an overlapping field of view creates a region of high-resolution with a high probability of detecting the objects that are present.  The system also overcomes noise problems of conventional radar systems.

The researchers developed new algorithms that can fuse the information from two different radar sensors and produce a new image free of noise.

Self-driving cars have to combine detection technologies like radar with cameras and ultrasonic sensors.  Duplicating the capabilities that people use in order to safely drive a car is a complex problem requiring a combination of multiple sensors and sophisticated software.

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Upgraded radar can enable self-driving cars to see clearly no matter the weather

Photo, posted January 2, 2014, courtesy of Bradley Gordon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Replacing Plastic Tableware | Earth Wise

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Plastics have been described as the “ubiquitous workhorse material of the modern economy.”  But their versatility, pliability, and durability comes at a heavy price to the environment.  Plastic pollution is quite literally everywhere.  Plastic debris and microplastic particles can be found in every corner of the globe, including the Arctic and Antarctic. 

The scourge of plastic pollution is driving scientists to create ecologically-friendly alternatives.  According to a paper recently published in the journal Matter, scientists have developed “green” tableware made from sugarcane and bamboo that doesn’t sacrifice on convenience or functionality.  This eco-friendly tableware could serve as a permanent replacement for plastic cups and other disposable plastic containers. 

Traditional plastic polymers, a product of petroleum, can take as long as 1,000 years to decompose in landfills.  The new material only takes 60 days to break down.

To create this material, scientists used bamboo and bagasse, also known as sugarcane pulp.  Bagasse is one of the largest food-industry waste products.  The researchers wound the fibers together to form a mechanically stable and biodegradable material.  They added an alkyl ketene dimer, an eco-friendly chemical, to increase the oil and water resistance of the material.  The green material is durable enough to hold liquids like hot coffee and hot greasy foods like pizza.   

There’s another advantage: the green material’s manufacturing process emits 97% less CO2 than the process to make commercial plastic containers.  The next step is to lower the manufacturing cost.  While the cost of cups made from the green material is $2,333 per ton, traditional cups made from plastic are still slightly cheaper at $2,177 per ton.

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This tableware made from sugarcane and bamboo breaks down in 60 days

Photo, posted May 19, 2013, courtesy of Henry Burrows via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Large Drop In U.S. Greenhouse Gas Emissions | Earth Wise

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Greenhouse gas emissions in the U.S. in 2020 are on track to be at their lowest level in nearly 30 years as a result of the COVID-19 pandemic.  U.S. emissions haven’t been this low since 1983, when the economy was not even 40% of its current size.

According to a new study by the research group BloombergNEF, U.S. emissions for the year will be 9% lower than they were in 2019, which will be the largest yearly drop on record.  The report also anticipates that whatever happens in the pandemic, 2021 emissions will be well below pre-COVID levels as well.

The pandemic has inadvertently put the U.S. back on track to meet its original commitments to the Paris Climate Agreement, despite the fact that we have pulled out the agreement.  The incoming administration plans to return the U.S. to the pact.

Overall, U.S. emissions have been trending downward since 2008, primarily as a result of the lower dependence of the power sector on coal.  The report estimates that in the absence of the pandemic, 2020 emissions would have been 1% lower than last year’s.

The dramatic drop in emissions is not really a great cause for celebration.  Achieving significant emission reductions through massive economic hardship and societal disruption does not point the way towards making progress on climate change.  The economic upturn that will undoubtedly occur when the pandemic loses its grip on the world will lead to rebounding levels of greenhouse gas emissions.  But as is the case with all major crises, the current situation does present a chance to turn this temporary downturn in emissions into a more permanent one by making appropriate investments and policy changes.

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Due to COVID-19, 2020 greenhouse gas emissions in the U.S. are predicted to drop to lowest level in three decades

Photo, posted January 13, 2013, courtesy of Onnola via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Europe’s Green Deal: Bad For The Planet? | Earth Wise

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In 2019, the European Union announced the “Green Deal,” a comprehensive program aimed at making Europe the first climate-neutral continent, implementing environmentally friendly transport, increasing recycling, and expanding renewable energy.

The Green Deal involves significant changes to European agriculture.  Over the next ten years, under the ambitious environmental program, at least a quarter of all agricultural areas will be farmed organically, the use of fertilizers and pesticides greatly reduced, 3 billion trees planted, 15,000 miles of rivers restored, and the population declines of pollinators reversed.

However, in a recent article published in Nature, scientists at the Karlsruhe Institute of Technology show that this Green Deal might actually be a bad deal for the planet.

The problem is that the EU is likely to basically be outsourcing environmental damage by its high imports of agricultural products.

According to the Karlsruhe study, the EU annually imports millions of tons of agricultural products, as much as 20% of its produce and much of its meat and dairy products.  Quite often, these imports come from countries whose environmental laws are far less stringent than those in Europe.

The EU cannot impose environmental standards on other countries, but it can demand that goods entering the European market meet EU requirements.  The study points out that Europe’s carbon footprint has to be evaluated on a global basis.  If the EU is truly to become a climate-neutral continent, it must include foreign trade goals and requirements in its environmental programs.  Otherwise, Europe will simply be outsourcing its environmental problems and will continue to cause damage to the planet.

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Green Deal: Good for a Climate-neutral Europe – Bad for the Planet

Photo, posted July 17, 2009, courtesy of Edmund Garman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The First Earth Fund Awards | Earth Wise

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Last February, Amazon CEO Jeff Bezos announced that he was launching the Bezos Earth Fund that would grant money to scientists, activists, NGOs and others making an effort to help preserve and protect the natural world.  The fund would start out with $10 billion and would begin issuing grants later in the year.

In November, the first Earth Fund award recipients were announced.  In total, 16 organizations will be receiving nearly $800 million in funding.

The largest awards include the following:  the Environmental Defense Fund received $100 million to build and launch MethaneSAT, a satellite that will locate and measure sources of methane pollution around the world and provide public access to data that assures accountability.

The Natural Resources Defense Council was awarded $100 million to advance climate solutions and legislation at the state level, promote policies and programs focused on reducing oil and gas production, protect and restore ecosystems that store carbon, and accelerate sustainable and regenerative agriculture practices.

The Nature Conservancy also received $100 million and plans to use the money to help protect the Emerald Edge forest.  (That is the largest intact coastal rainforest on Earth, spanning 100 million acres through Washington, British Columbia and Alaska).

The World Resources Institute will receive $100 million, doled out over five years, to be used to develop a satellite-based monitoring system to advance natural climate solutions around the world.

An additional $100 million award went to the World Wildlife Fund to help protect and restore mangroves, develop new markets for seaweed as an alternative to fossil fuel-based products, and to protect forests and other ecosystems around the world.

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The organizations that will benefit from Bezos’ $791M and what will they do with the money

Photo, posted March 4, 2015, courtesy of Kevin Gill via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Why Do Trees Change Color? | Earth Wise

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We had a particularly colorful fall in the Northeast this year.  Almost everywhere you looked, there were brilliant displays of yellow, orange, and red.  The colors of fall are a result of chemistry and environmental events that may have taken place many months in the past.

The color of leaves comes from 4 pigments whose effects are governed by photosynthesis.  The one that is actually used in photosynthesis is chlorophyll and it causes leaves to be green.  But when a tree begins to prepare for dormancy, it stops producing chlorophyll, the green pigmentation fades, and the other pigments that were already in the leaves become visible.

There are xanthoplylls, which are the yellow pigments that are seen the most in fall trees.  They are the same pigments that color egg yolks and sometimes parts of the human eye.  They are only produced by plants and appear in humans and animals only through consumption.

There are carotenes, which are the orange pigments found in fruits and vegetables, such as carrots, oranges, some bell peppers and squashes.

And there is anthocyanin, which is the pigment found in blueberries, blackberries, and red or violet roses.  Its color depends on the pH level of the plant; higher pH leads to darker color.  This is the pigment seen in red maples, black cherry trees, Shumard oaks, and more.  Only 10% of trees in temperate climates produce anthocyanin and its red pigmentation and most of those trees are in New England.

All these pigments serve purposes.  They help trees absorb light energy, prevent sun damage, and even regulate how much energy chlorophyll produces.

There are complicated chemical and environmental factors at play in fall foliage but when they come together like they did this year, it’s a magnificent spectacle.

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Why Do Trees Change Color?

Photo, posted October 17, 2020, courtesy of John Brighenti via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Finding Methane Leaks from Space | Earth Wise

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There is growing concern about the climate effects of methane leaking from oil and gas wells.  The 20-year global warming potential of methane is 84, meaning that over a 20-year period, it traps 84 times more heat per mass unit than carbon dioxide.  Global methane concentrations have increased by nearly a factor of 3 since the industrial revolution.

More than a century of oil and gas drilling has left behind millions of abandoned wells, many of which are leaching pollutants into the air and water.   In the U.S. alone, more than 3.2 million abandoned oil and gas wells emitted 280,000 tons of methane just in 2018.  And the data is incomplete.

Part of the problem is finding out which wells are leaking.  Ground-based sensors or airplanes and drones are effective ways to find leaks but considering how many wells there are to check, the costs are considerable, and the process is time consuming and complicated. 

New technology is coming along that uses satellites to detect methane leaks.  A Canadian company called GHGSat recently used satellites to detect what it has called the smallest methane leak ever seen from space and has begun selling data to emitters interested in pinpointing leaks.

Another company, New York-based Bluefield Technologies, plans a group of satellites for launch in 2023 that promises even finer resolution.  The Environmental Defense Fund, with support from Jeff Bezos’ Earth Fund, plans to launch MethaneSAT in the next couple of years, which is designed to find small sources of methane.

Research at Stanford University determined that just 5% of methane leaks produce around half the total leakage. 

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New Technology Claims to Pinpoint Even Small Methane Leaks From Space

Photo, posted June 8, 2011, courtesy of Jeremy Buckingham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Renewable Growth During The Pandemic | Earth Wise

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According to a new report published by the International Energy Agency, global renewable energy installations will hit a record level in 2020 in sharp contrast with declines in the fossil fuel sectors caused by the Covid-19 pandemic.

For the year, almost 90% of all new electricity generation will be renewable, with only 10% powered by gas and coal.  This progress puts green power on track to become the largest global electricity source by 2025, displacing coal-powered generation, which has been dominant for the past 50 years.  By that year, renewables are expected to supply one-third of the world’s electricity.

Solar power capacity has increased by 18 times since 2010 and wind power by four times.  In 2010, hydropower provided 77% of the world’s green power, but its share has fallen to 45% – not because there is less hydropower but because solar and wind have grown so much.

Growing recognition of the need to tackle the global climate crisis has made renewable energy increasingly attractive to investors.  According to the IEA report, shares in renewable equipment makers and project developers have outperformed most major stock market indices and the value of shares in solar companies has more than doubled in the past 12 months. Fossil fuels have had a turbulent time in 2020 as the pandemic has caused demand from transport and other sectors to plunge.

While renewables continue to see dramatic growth in electrical generation capacity, electricity represents only about one-fifth of all energy use.  The burning of fossil fuels in transport, industry, and heating continues to make up the bulk of energy emissions.

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Renewable energy defies Covid-19 to hit record growth in 2020

Photo, posted October 2, 2020, courtesy of the Bureau of Land Management California via Flickr. Photo credit: Clearway Energy Group.

Earth Wise is a production of WAMC Northeast Public Radio.

Return Of The Blue Whales | Earth Wise

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An international research team has revealed that critically endangered Antarctic blue whales have returned to the sub-Antarctic island of South Georgia, 50 years after whaling just about wiped them out.  Other recent research has found that humpback whales are also returning to the region.

Blue whales were commonplace off South Georgia before 20th century industrial whaling taking place between 1904 and 1971 killed over 42,000 of them there.  Most of that number were killed before the mid-1930s.  As a result, blue whales essentially vanished from the region.  Whale survey ships sighted only a single blue whale between 1998 and 2018.

But things have changed in recent years.  A survey this past February resulted in 58 blue whale sightings and numerous acoustic detections.  Although commercial whaling was banned in the area in the 1960s, it has taken a long time for the whales to make a comeback.

Researchers are not sure why blue whales have taken so long to return to the area.  It may be that so many were killed over the years that the remaining population had little or no cultural memory of South Georgia Island as a foraging ground, and that it is only now being rediscovered.

In total, 41 individual blue whales have been photo-identified from South Georgia over the past 10 years, although none of those matched the 517 whales in the current Antarctic blue whale photographic catalogue.  Dedicated whale surveys are difficult in a region known for its harsh weather and inaccessibility but are crucial to the future management of South Georgia’s seas.  In any case, researchers see the recent sightings as a very positive step forward for conservation of the Antarctic blue whale. 

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Blue whales return to South Georgia after near extinction

Photo, posted September 7, 2007, courtesy of the NOAA Office of National Marine Sanctuaries via Flickr. Photo credit: NOAA.

Earth Wise is a production of WAMC Northeast Public Radio.

Hydrogen-Powered Jetliners | Earth Wise

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Airbus, the giant European aerospace company, hopes to have hydrogen-powered commercial airliners in the sky by 2035.  Such planes would have no carbon dioxide emissions.

Greenhouse gas emissions from commercial aviation have been a rapidly increasing contribution to the global total.  Of course, the Covid-19 pandemic has drastically reduced air travel, so emissions are currently lower than they have been in a very long time.  But at some point, they will resume at previous levels and continue to increase.

Planes themselves produce over 2% of global CO2 emissions, and between the climate effects of contrails and the emissions associated with the rest of the air travel industry, commercial aviation drives about 5% of global warming.

Airbus is studying design concepts in which planes run off of hydrogen and oxygen fuel and have no carbon exhaust.   Making such planes practical and environmentally advantageous requires solving an array of complex technical challenges. 

One of the biggest challenges is that the hydrogen on the market today is considered to be “brown” rather than green, meaning that it is not a sustainably produced energy source.  Almost all hydrogen produced today comes from natural gas reforming, which results in carbon emissions.  A viable hydrogen-powered aviation technology assumes that producing hydrogen by splitting water molecules into oxygen and hydrogen using renewable energy becomes the standard source for it.

There have been test flights of small planes and drones powered by hydrogen, but Airbus expects that intensive research and development for the next five years will be required to evolve its current preliminary designs to a stage where they could be developed for future use in its product line.  It won’t happen overnight, but according to Airbus, hydrogen planes are coming.

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Airbus Hopes to Be Flying Hydrogen-Powered Jetliners With Zero Carbon Emissions by 2035

Photo, posted April 15, 2019, courtesy of Olivier Cabaret 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...)