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A Hot July | Earth Wise

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The numbers are in and, unsurprisingly, July was a hot month.  July 2020 tied for the second-hottest July on record for the planet, according to the National Oceanic and Atmospheric Administration.  In our own backyard, the Northern Hemisphere saw the hottest July ever, breaking the previous record set just last year.

The July 2020 global temperature was 62.06 Fahrenheit, which is 1.66 degrees above the 20th-century average.  The combined land and ocean surface average temperature for the Northern Hemisphere, the highest ever recorded for July, was 2.12 degrees F above average, breaking the previous record by 0.14 degrees.

Record-hot July temperatures were also recorded across parts of southeastern Asia, northern South America, across the west and northern Pacific Ocean, the northern Indian Ocean, and parts of the Caribbean Sea.

The year-to-date global land and ocean surface temperature was the second highest in the 141 years of record keeping at 58.79 degrees Fahrenheit, which is 1.89 degrees F above the 20th-century average. 

So far it is been the hottest year to date on record across a large portion of northern Asia, parts of Europe, China, Mexico, northern South America, as well as the Atlantic, northern Indian and Pacific oceans.

Meanwhile, the extent of sea ice in the Arctic for July 2020 was the smallest ever measured in the 42 years of record-keeping, over 23% below the 1981-2010 average.  July’s Arctic sea ice extent was smaller than the previous record (set last year) by 120,000 square miles, an area roughly the size of New Mexico.

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July 2020 was record hot for N. Hemisphere, 2nd hottest for planet

Photo, posted July 24, 2018, courtesy of Maria Eklund Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Giant Jellyfish | Earth Wise

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There have been recent news stories about giant jellyfish washing ashore from Maine to the south coast of Massachusetts.  These stories have claimed that some of these lion’s mane jellyfish have been the largest on record and even might be the largest animals in the ocean.

The truth of these accounts is rather suspect.  For one thing, it is rather difficult to measure the size of a jellyfish when it is out of the water.  Gravity compresses and spreads out the bell portion of the animal, and that makes up the bulk of its mass.  For example, a jellyfish bell that measures four feet across on the beach would appear to be much smaller if the animal was floating in the water.

Some claims that lion’s mane jellyfish are larger than blue whales date back a full century and are very much disputable.  The claimed size certainly included the animal’s long tentacles, and such things hardly compare with a blue whale.

In any event, the current spate of jellyfish sightings is not necessarily that unusual.  Many factors influence jellyfish populations, including water temperature and food supply.  It is possible that warming water temperatures may be influencing the jellyfish population this year, but there is not enough data to know for sure.

People do need to be cautious around lion’s mane jellyfish.  They do sting and while their stings are not as bad as those of a number of other species, they can be a problem for people who have allergic reactions.  Furthermore, the stinging cells remain active in a jellyfish that has washed ashore.

Sightings of these animals are continuing, and reports of larger specimens continue as well, even if they don’t compare with blue whales.

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Jellyfish larger than blue whales?

Photo, posted September 13, 2015, courtesy Derek Keats via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plant-Based Bottles | Earth Wise

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Single-use plastic soda and water bottles are a real problem.  Every year, billions of them are produced – comprising nearly 300 million tons of plastic that mostly ends up in landfills or in the ocean.   This discarded plastic ends up on remote islands, in the snow atop mountains, and in trenches in the deepest parts of ocean.

There has been increasing pressure on beverage companies to put an end to this environmental disaster, but the convenience and economy of disposable bottles is just too attractive.

These bottles are made of plastic derived from oil and once they are produced, they take decades or even centuries to decompose.  Recycling them is a not-starter because it is cheaper to just make new ones.

A possible solution has emerged.  A Dutch company called Avantium has found a way to take plant sugars and transform them into a plastic capable of standing up to carbonated beverages like soda and beer but that will also break down in as little as a year in a composter or 3 years if left exposed to the elements.

Coca Cola and Carlsberg are working with Avantium to develop new drink packaging based on their material that could be in stores as soon as 2023.  The new packaging would be quite different from what we use today.  Instead of a clear or tinted bottle, beverages would come inside a cardboard container with a liner made of plant-based plastic.

It may take a while for people to get used to the change, but we have already managed to get used to milk, juice and other liquids coming in cardboard containers instead of glass or plastic bottles.  The benefits to the planet would make the effort well worthwhile.

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Plant-Based Bottles Could Degrade In One Year

Photo courtesy of Avantium.

Earth Wise is a production of WAMC Northeast Public Radio.

Heat-Resistant Coral | Earth Wise

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Coral reefs are in decline all over the world.  Corals are under increasing pressure as water temperatures rise and the frequency and severity of coral bleaching events increase.  Nowhere is this more evident than in Australia’s Great Barrier Reef system, where severe bleaching events have happened in three of the past five years. Long-term prospects for the survival of the world’s largest reef system are now considered to be poor.

A team of scientists at Australia’s national science agency – the Commonwealth Scientific and Industrial Research Organization – along with the Australian Institute of Marine Science and the University of Melbourne have successfully produced in a laboratory setting a coral that is more resistant to increased seawater temperatures.

The team made the coral more tolerant to temperature-induced bleaching by bolstering the heat tolerance of the microalgae symbionts that live inside the coral tissue.  They isolated the microalgae from coral and cultured it in the laboratory using a technique called “directed evolution”.  Over the course of four years, they exposed the microalgae to increasingly warmer temperatures.  When the heat-adapted strain of algae was reintroduced into coral larvae, the newly established coral-algal symbiosis was more heat tolerant than the original one.  The heat-tolerant microalgae are better at photosynthesis and improve the heat response of the coral animal.

The next step is to further test the algal strains in adult colonies across a range of coral species.  This groundbreaking research provides a promising and novel tool to increase the heat tolerance of corals and might potentially lead to a way to save the Great Barrier Reef as the world continues to warm.

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Scientists successfully develop heat resistant coral to fight bleaching

Photo, posted September 22, 2010, courtesy of NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Floating Turbines For Offshore Wind | Earth Wise

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Offshore wind is big in Europe.  There are more than 5,000 offshore wind turbines across 12 European countries with a total capacity of more than 22 gigawatts.  Almost every one of those turbines sits on a long tower sunk into the seabed and bolted into place in places where the water is 60 to 160 feet deep.

But off the coast of northern Scotland, there is the Hywind Wind Park which has five 574-foot-tall turbines located 15 miles offshore where the water is 300 feet deep.  The giant masts and turbines sit on buoyant concrete-and-steel keels that allow them to stand upright and float on the water like a giant buoy.  The giant cylindrical bases are held in place with mooring cables attached to anchors that sit on the seafloor.

A key advantage of floating turbines is that they can access outlying ocean waters up to half a mile deep, which is where the world’s strongest and most consistent winds blow.  Another advantage is that such turbines can be installed over the horizon, out of sight of coastal residents who might not like to have wind turbines visible in their scenic ocean views.

Floating wind power has enormous potential for contributing to the expansion of renewable energy.  Offshore wind is still quite a bit more expensive than land-based turbines, and the cost of electricity from distant floating turbines is more than that from near-shore wind turbines.   But all of these costs are likely to come down with improving technology and increased production volume.

There are real challenges to the expanded used of floating wind farms, but the promise of harnessing so much of the open seas for electricity generation is an attractive proposition.

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Will Floating Turbines Usher in a New Wave of Offshore Wind?

Photo, posted July 17, 2017, courtesy of Crown Estate Scotland via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Microplastic Hotspots In The Ocean | Earth Wise

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Many of us are aware of the infamous ocean “garbage patches” of floating plastic.  The Great Pacific Garbage Patch is roughly the size of Texas.  But over 10 million tons of plastic waste enter the oceans each year and the floating patches only account for 1% of that total.  The remaining 99% of the plastic ends up in the deep ocean, generally in the form of microplastics – tiny fragments of large plastic debris that have broken down as well as manufactured polyethylene beads used in various products.

According to a new study published in the journal Science, there are actually microplastic hotspots on the ocean floor, formed by deep-sea currents that act as conveyer belts moving the tiny plastic fragments around.  One of these hotspots – in the Tyrrhenian Sea off the west coast of Italy – contained 1.9 million microplastic pieces in just one square meter of seafloor.  This is the highest reported value for any place in the world.

Because of their small size, microplastics can be ingested by organisms across all levels of the marine food chain and eventually find their way into human diets. 

The spatial distribution and ultimate fate of ocean microplastics are strongly controlled by near-bed thermohaline currents.  These are deep-ocean currents driven by differences in water density, which is controlled by temperature and salinity.  Thermohaline currents are known to supply oxygen and nutrients to the flora and fauna found at the ocean bottom.  As a result, deep sea biodiversity hotspots are likely to be in same places where there are microplastic hotspots.

The discovery of these deep- sea hotspots is just another reason why we need behavior and policy interventions to limit the flow of plastics into natural environments.

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Seafloor microplastic hotspots controlled by deep-sea circulation

Photo, posted September 6, 2012, courtesy of Oregon State University via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Victory For Clean Water | Earth Wise

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Many of the nation’s environmental laws are under siege from the current administration, but a recent decision by the U.S. Supreme Court has solidified the Clean Water Act’s place as one of the country’s most effective environmental laws.

The case in question was about whether a wastewater treatment plant in Maui has been violating the Clean Water Act by polluting the ocean indirectly through groundwater.  Since the 1980s, the Lahaina wastewater treatment facility has been discharging millions of gallons of treated sewage each day into groundwater that reaches the waters off of Kahekili Beach, which is a popular snorkeling spot.   Groundwater, like any water beneath the land’s surface, can flow into major waterways such as rivers, streams, and, in this case, the ocean. 

In 2012, the nonprofit Earthjustice sued Maui county on behalf of four Maui community groups. Over the years, the Hawaii district court and the 9th Circuit appeals court ruled in favor of Earthjustice.  Last year, Maui County successfully petitioned the U.S. Supreme court to hear the case, which could have endangered the Clean Water Act.

On April 23, by a 6-3 vote, the court ruled that point source discharges to navigable waters through groundwater are regulated by the Clean Water Act when the addition of pollutants through groundwater is the functional equivalent of a direct discharge into navigable waters.

With this ruling, the Court rejected the Trump administration’s polluter-friendly position in the clearest of terms.  According to the opinion, written by Justice Breyer, the Court could not see how Congress could have intended to create such a large and obvious loophole in one of the key innovations of the Clean Water Act.  This is a victory for clean water.

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The Clean Water Case of the Century

Photo, posted June 30, 2018, courtesy of Kirt Edblom via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Boutique Hotels For Birds | Earth Wise

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The changing Arctic climate has had a drastic effect on its seabirds.  In fact, seabirds worldwide are in crisis, with global populations plummeting nearly 70% over the past 70 years as a result of climate change, over-fishing, habitat loss, and other human impacts on their environment.

Above the Arctic circle in Norway, seabird behavior has changed dramatically.  Black-legged kittiwakes – which are the most seafaring member of the gull family – used to nest in cliffs over the ocean and seldom ventured inland.  But in recent years, that has changed.  Because of a warming ocean, increased storminess and other changes that are decimating chick populations in their normal habitat, the birds have been setting up housekeeping in places like shopping centers and office buildings in Tromsø and other towns along Norway’s north coast.

Tromsø, Hammerfest and other towns at the very north end of Norway have become very popular with tourists seeking the Northern Lights and wanting to see glaciers before they disappear.  The booming tourism has been put on hold for the moment as it has elsewhere, but when it returns, the regions growing hotels and shopping areas are facing a problem.

The birds taking up residence on these buildings are unpleasant neighbors.  They are especially noisy during the breeding season and people are having to put up nets or spikes on buildings to discourage the kittiwakes from settling there.

Local ecologists are now building boutique hotels just for kittiwakes. Using abandoned buildings on piers, they are adding ledges for nesting, materials for nest-building, and electronic speakers that croon kittiwake songs.  The hope is that the birds will stay in their own hotels and leave the other ones for the human tourists.

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Norwegians are building boutique hotels for threatened Arctic birds

Photo, posted April 14, 2018, courtesy of Charlie Jackson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Hidden Source Of Arctic Carbon | Earth Wise

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Researchers from the University of Texas at Austin, the U.S. Fish and Wildlife Service, and Florida State University have published a paper presenting evidence of significant and previously undetected concentrations and fluxes of dissolved organic matter entering Arctic coastal waters.  The source of the organic matter is groundwater flow atop the frozen permafrost.  The groundwater moves from land to sea unseen, but the new research reveals that it carries significant concentrations of carbon and other nutrients to Arctic coastal food webs.

Globally, groundwater is important for delivering carbon and other nutrients to oceans, but in the Arctic, where much water is trapped in the permafrost, its role was thought to be minimal.  But the new research reveals that groundwater may be contributing an amount of dissolved organic matter to the Alaskan Beaufort Sea that is comparable to what comes from neighboring rivers during the summer.

The researchers found that shallow groundwater flows beneath the surface and picks up new, young organic carbon and nitrogen, but it also mixes with layers of deeper soils and thawing permafrost, picking up and transporting century-to-millennia old organic carbon and nitrogen.  This material is unique because it is directly transported to the ocean without seeing or being photodegraded by sunlight and may be valuable as a food source to bacteria and higher organisms that live in Arctic coastal waters.

The study concluded that the supply of leachable organic carbon from groundwater amounts to as much as 70% of the dissolved organic matter that enters the Beaufort Sea from rivers during the summer.  The role that groundwater inputs play in Arctic coastal ecosystems will be an area of active research for years to come.

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Hidden Source of Carbon Found at the Arctic Coast

Photo, posted June 14, 2015, courtesy of Eugen Marculesco via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Keep Track Of Your LEGOs | Earth Wise

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Plastics in the ocean are a global problem that has attracted a great deal of attention.  Most of the concern surrounds grocery bags, bottles, six-pack rings, and similar items.  Recent research looked at another source of plastic pollution:  LEGOs.

According to environmental scientists at the University of Plymouth in the United Kingdom, it can take more than a thousand years for LEGO bricks to break down in the ocean.  The iconic toys are made from a strong plastic called acrylonitrile butadiene styrene or ABS.  Pieces of LEGOs are commonly found in ocean trash hotspots and wash up on shores across the globe by the thousands.

LEGOs are one of the most popular children’s toys in history and part of what makes them so popular is their durability.  Barefooted parents stepping on one on the floor in a dark room can attest to that fact.  But the full extent of their durability came as a surprise to the researchers.

The scientists analyzed pieces of weathered LEGOs collected from beaches, confirmed their age, and compared them to unweathered LEGOs from the 70’s and 80’s.  They were able to determine the extent to which LEGOs had been worn down by ocean waves, sand, and salt over time.  And it was surprisingly little.

LEGO has acknowledged the environmental impact of its products and has launched a goal to make its bricks from more sustainable sources such as sugarcane-based polyethylene by 2030, as well as improve its efforts to recycle and reuse old LEGO plastic.

Meanwhile, we should all we careful of where our old LEGOs end up.

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LEGO Bricks Could Linger in the Ocean for 1,300 Years, Study Finds

Photo, posted August 24, 2015, courtesy of Juan Luis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Devastating Threat To Coral Reef Habitats | Earth Wise

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According to new research from scientists at the University of Hawaii Manoa, the warming and acidifying oceans could wipe out nearly all existing coral reef habitats by 2100.  In fact, the researchers predict that 70-90% of coral reefs will disappear over the next 20 years alone as a consequence of climate change and pollution. 

Some organizations are attempting to save coral habitats by transplanting live corals from labs to reefs.  The idea is that the new young corals will help revive the reefs.  But after mapping where such restoration efforts would be most successful, the research indicates that there will be little to no suitable habitat remaining for corals by 2100.  Small portions of Baja California and the Red Sea are two of the sites that could remain viable by 2100, although neither are ideal due to their proximity to rivers.  Sea surfaces temperature and acidity are two of the most important factors in determining the viability of a site for restoration.  

Warming ocean waters stress corals, which cause them to expel the symbiotic algae living inside them.  This turns the often colorful corals white – an event known as coral bleaching.  Bleached corals are not dead corals, but they are at a higher risk of dying.  These coral bleaching events are becoming more frequent as a result of the changing climate. 

The projected increases in human pollution will only play a minor role in the future elimination of coral reef habitats.  Ironically, that’s because humans have already caused such extensive damage to coral reefs that there aren’t many locations left to impact.

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Warming, acidic oceans may nearly eliminate coral reef habitats by 2100

Photo, posted September 28, 2009, courtesy of Matt Kieffer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Harvesting Blue Energy | Earth Wise

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There are various ways to generate renewable energy from the world’s oceans, most obviously from the power of tides and waves.  But there is also an oceanic energy source called osmotic or “blue” energy.  Osmotic energy uses the differences in pressure and salinity between freshwater and saltwater to generate electricity. 

When freshwater and saltwater are mixed together, large amounts of energy are released. If the freshwater and seawater are then separated via a semi-permeable membrane, the freshwater will pass through the membrane and dilute the saltwater due to the chemical potential difference. This process is called osmosis. If the salt ions are captured completely by the membrane, the passing of water through the membrane will create a pressure known as osmotic pressure. This pressure can be used to generate electricity by using it to drive a turbine.  This has been demonstrated to work as far back as the 1970s, but the materials we have to use are not adequate to withstand ocean conditions over the long term and tend to break down quickly in the water.

New research, published in the journal Joule, looked to living organisms for inspiration to develop an improved osmotic energy system.  Scientists from the U.S. and Australia combined multiple materials to mimic the kind of high-performance membranes that are found in living organisms.  They created a hybrid membrane made from aramid microfibers (like those used in Kevlar) and boron nitride.  The new material provides both the flexibility of cartilage and the strength and stability of bone.

The researchers believe that the low cost and high stability of the new hybrid membrane will allow it to succeed in volatile marine environments.  They also expect the technology will be both efficient and scalable. 

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Inspired by the Tissues of Living Organisms, Researchers Take One Step Closer to Harvesting “Blue Energy”

Photo, posted February 14, 2017, courtesy of Marian May via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Much More Microplastics In The Ocean | Earth Wise

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We’ve been hearing more and more about plastic contamination (microplastics) in the ocean.  It is pulled from the nostrils of sea turtles, found in Antarctic waters, and tracked in increasing quantities in sedimentary layers dating back to the 1940s.  A new study by researchers from the Scripps Institution of Oceanography suggests that there could be a million times more pieces of plastic in the ocean than previously estimated.

Oceanographers found that some of the tiniest countable microplastic particles in seawater occur at much higher concentrations than previously measured.  Apparently, the traditional way of counting marine microplastics most likely misses the smallest particles, and therefore underestimates the number of particles by a factor of anywhere from 10,000 to a million.

The new measurements estimate that the oceans may be contaminated by 8 million pieces of so-called mini-microplastics per cubic meter of water.  Earlier studies that only looked at larger pieces of plastic found only 10 pieces per cubic meter. 

Microplastic studies typically trawl or pull a fine net behind a ship to collect samples.  But the meshes previously used could only capture plastics as small as 333 microns.  The new study found plastic particles as small as 10 microns, which is less than the width of a human hair.

Plastics keep breaking down into smaller and smaller particles, but they are so chemically strong that their chemical bonds don’t break down. They remain bits of plastic.  Scientists are concerned that these particles can get small enough to enter the human bloodstream.  The potential effects on human health are not well known and not extensively studied.

The problem of plastics just keeps getting bigger.

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Microplastics a million times more abundant in the ocean than previously thought

Photo courtesy of UC San Diego.

Earth Wise is a production of WAMC Northeast Public Radio.

Turning CO2 Into Rock

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As the world continues to struggle to find ways to reduce carbon emissions, there is increasing attention being paid to so-called negative emission technologies (NET), which remove and permanently sequester carbon dioxide from the atmosphere.

The University of Victoria in British Columbia has brought together an international team of experts to explore the possibilities of permanently and safely sequestering CO2 as rock beneath the ocean floor.  The Solid Carbon Project seeks to extract carbon dioxide directly from the air and then, using deep-ocean technology powered by offshore solar and wind energy, inject it into sub-seafloor basalt, where it would mineralize into solid carbonate rock.

When CO2 is injected into porous basalt, a type of volcanic rock, it reacts relatively quickly with minerals to form solid carbonate, thereby permanently removing it from the atmosphere.  Because 90% of the planet’s basalt is located beneath the ocean floor, the deep ocean is the place to do this kind of carbon sequestration.

The team includes experts in ocean science, carbon mineralization, renewable energy, engineering design, and oil-and-gas drilling/injection operations. Other experts are focusing on the social and legal implications of the NET technology.

Over the next four years, the Solid Carbon Project will assess the integration of multiple existing technologies that will be needed to successfully develop this kind of carbon storage.  One of these is the direct air capture technology itself, which will need to be adapted to a renewable energy-powered offshore platform.  The best outcome technologies explored by the project will be selected for a real-world demonstration at Ocean Networks Canada’s observatory site, 9,000 feet underwater in the Cascadia Basin, off the coast of British Columbia.

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A rock-solid solution for CO2

Photo courtesy of the University of Victoria.

Earth Wise is a production of WAMC Northeast Public Radio.

Another Hot November

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This past fall saw yet more of the high temperatures the world has been experiencing in recent times.  Both the season (September through November) and the year to date were the second hottest in recorded history.  November itself was the second-hottest November in the 140-year global climate record.

The high temperatures were felt at both ends of the world.  Sea ice coverage across both the Arctic and Antarctic oceans fell to near-record lows in November.  Arctic sea ice coverage was nearly 13% below the 1981-2010 average, while Antarctic coverage was 6.35% below average.

The average global land and ocean surface temperature for November was 1.66 degrees Fahrenheit above the 20th century average.  The year-to-date global temperature was 1.69 degrees Fahrenheit above the 20th century average.  These numbers correspond to almost a 1-degree Celsius increase, which should be compared with the Paris Climate Accord goal of keeping that increase to no more than 1.5 degrees.

November was the hottest November on record for South America, Africa, and the Hawaiian Islands.  The Caribbean had its second-hottest November, and Europe had its seventh hottest on record.

The world’s average sea surface temperature ranked second warmest for the year to date and was only 0.05 degrees cooler than the all-time record.

The National Oceanic and Atmospheric Administration issues monthly global climate reports and for quite some time, these reports seem to all be the same.  Another new record for heat or at least another near record.  We have to expect that this trend will continue at least until the world starts making progress in dealing with its root cause.

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November 2019 was 2nd hottest on record for the planet

Photo, posted July 20, 2016, courtesy of Salehin Chowdhury via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Community Action And Coral Reefs

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Coral reef habitats are some of the densest and most varied ecosystems on earth.  While coral reefs cover just 0.2% of the ocean floor, scientists estimate that nearly one million different species of fish, invertebrates, and algae can be found in or around coral reefs. 

However, climate change is wreaking havoc on the health of coral reefs.  Warming and acidifying oceans are resulting in enormous coral losses.  Overfishing, development, and pollution are also threatening coral reef health.

According to new research, positive community action can help boost fish populations in coral reefs and safeguard future fish numbers.  The paper, which was recently published in the journal Proceedings of the National Academy of Sciences, details the social and ecological outcomes of work being done in Papua New Guinea since 2001. 

These communities have established a traditional system of rotational fishing closures in order to manage their fisheries resources.   They ban fishing on part of their reefs for a few years, and then open these closures when village elders believe fish behavior has changed and fish populations have recovered.  They then close a different part of their reefs, and repeat the process. 

The researchers found that these rotational practices resulted in more than twice as many fish on the closed reefs as compared to open ones, and the closures made fish less scared of people and easier to catch.  But the researchers did caution that this short term boost in fish numbers may not be enough to stop the overall impact of fishing.

Globally, more than 500 million people depend on coral reefs for food, income, and coastal protection.  Balancing community needs with environmental needs can be tricky business.  

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Positive community action can help coral reef health

Photo, posted October 11, 2011, courtesy of Paul Toogood via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Turning Trash Into Treasure

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Every year, 380 million tons of plastic are created worldwide, and that number continues to grow.  Furthermore, more than 75% of these materials are discarded after one use.  Much of it ends up in oceans and waterways, harming wildlife and spreading toxins.

Recycling most plastics is difficult because while they can be melted and reprocessed, the resultant material is not as structurally strong as the original material.  Thus, plastics are often down-cycled such as turning plastic bottles into molded park benches.

Researchers at Northwestern University, Argonne National Laboratory, and Ames Laboratory have developed a new method for upcycling abundant, seemingly low-value plastics into high-quality liquid products, such as motor oils, lubricants, detergents, and even cosmetics.  The catalytic method  could remove plastic pollution from the environment and contribute to a circular economy.

Plastics don’t degrade when disposed of because they have very strong carbon-carbon bonds.  Instead they just break into smaller bits, known as microplastics.  The researchers viewed these strong bonds as an opportunity rather than a problem.

The new technique actually recoups the high energy that holds these bonds together by catalytically converting polyethylene molecules into value-added commercial products.  The catalyst consists of platinum nanoparticles deposited onto perovskite nanocubes.  Under moderate pressure and temperature, the catalyst cleaves the carbon-carbon bonds in plastic to produce high-quality liquid hydrocarbons. 

The researchers believe these findings could lead to a future in which we can continue to benefit from plastic materials but do so in a way that is sustainable and less harmful to the environment.

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Turning plastic trash into treasure

Photo, posted August 15, 2012, courtesy of Emilian Robert Vicol via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And El Niño

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The term El Niño refers to a large-scale ocean-atmosphere climate interaction linked to a periodic warming in sea surface temperature across the central and east-central equatorial Pacific Ocean.  Amazingly, the phenomenon was originally recognized by fishermen off the coast of South America in the 1600s, with the appearance of unusually warm water in the Pacific Ocean.

According to a new study published in the Proceedings of the National Academy of Sciences, climate change is increasing the frequency of extreme El Niño events, leading to intensifying droughts, worsening floods, and shifting hurricane patterns.

The study, led by scientists in China and the US, looked at data from 33 El Niños dating back to 1901.  Since the 1970s, El Niños have been forming farther to the west in the Pacific Ocean, where temperatures are warmer.  Strong El Niños can cause severe drought in dry climates such as Australia and India, intense flooding in wetter climates such as the US Pacific Northwest and Peru, and more hurricanes to form in the Pacific and fewer in the Atlantic.

Before 1978, 12 out of 14 El Niños formed east of the International Dateline.  Since 1978, all 11 have formed in the central or western Pacific Ocean a shift of hundreds of miles.  There have been three so-called super El Niños since the shift – in 1982, 1997, and 2015.  These have set new average temperature records and triggered catastrophic natural disasters.

With rising global temperatures, El Niños are likely to continue to intensify, with major impacts on human societies around the world.

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Climate Change is Making El Niños More Intense, Study Finds

Photo, posted January 20, 2016, courtesy of Los Angeles District via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Ocean Acidification And Mass Extinction

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Since the industrial revolution, the concentration of carbon dioxide in the atmosphere has increased due to the burning of fossil fuels and land use changes.  The ocean absorbs about 30% of the CO2 that is released in the atmosphere.  As the levels of atmospheric CO2 increase, so do the levels in the ocean.

When CO2 is absorbed by the ocean, a series of chemical reactions occur, resulting in seawater becoming more acidic.  Ocean acidification threatens calcifying organisms, such as clams and corals, as well as other marine animals, like fish.  When these organisms are at risk, the entire marine ecosystem may also be at risk.

In fact, according to research recently published in the journal Proceedings of the National Academy of Sciences, fossil evidence from 66 million years ago has revealed that ocean acidification can cause the mass extinction of marine life.  Researchers analyzed seashells in sediment laid down shortly after a giant meteorite hit earth.  This strike wiped out the dinosaurs and 75% of marine species.  Chemical analysis of the shells revealed a sharp drop in the PH of the ocean over hundreds of years after the meteorite strike.  The meteorite impact vaporized rocks, causing carbonic acid and sulphuric acid to rain down, acidifying the ocean.  The strike also resulted in mass die-off of plants on land, increasing atmospheric CO2.  

Researchers found that the pH dropped by 0.25 pH units in the 100 to 1,000 years after the meteorite strike.  Alarmingly, scientists expect the pH of the ocean to drop by 0.4 pH units by 2100 if our carbon emissions continue as projected. 

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Ocean acidification can cause mass extinctions, fossils reveal

Photo, posted March 16, 2017, courtesy of Zachary Martin 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...)