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Mealworms And Plastic | Earth Wise

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Mealworms are widely cultivated beetle larvae that people feed to pets and to wild birds.  But it turns out, they may have an even more valuable purpose:  they can eat plastic and even plastic containing dangerous chemical additives.

Four years ago, researchers at Stanford discovered that mealworms can actually subsist on a diet of various types of plastic.  They found that microorganisms in the worms’ guts actually biodegrade the plastic.  It might be possible to cultivate the worms using unrecyclable plastic, rather than feeding them grains and fruits.   However, there is the issue of whether it would be safe to feed the plastic-eating worms to other animals, given the possibility that harmful chemicals in plastic additives might accumulate in the worms over time.

Recently, the Stanford researchers studied what happens when the worms ingested Styrofoam or polystyrene.  The plastic commonly used for packaging and insulation typically contains a flame retardant called hexabromocyclododecane, or HBCD.  Studies have shown that HBCD can have significant health and environmental impacts, ranging from endocrine disruption to neurotoxicity.

According to the study, mealworms in the experiment excreted about half of the polystyrene they consumed as tiny, partially degraded fragments and the other half as carbon dioxide.  With it, they excreted the HBCD.  Mealworms fed a steady diet of HBCD-laden polystyrene were as healthy as those eating a normal diet.  And shrimp fed a steady diet of the HBCD-ingesting mealworms also had no ill effects.

It is true that the HBCD excreted by the worms still poses a hazard and must be dealt with in some manner, but mealworms may have a role to play in dealing with unrecyclable plastics like Styrofoam.

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Stanford researchers show that mealworms can safely consume toxic additive-containing plastic

Photo, posted May 11, 2015, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Converting A Toxin Into An Industrial Chemical | Earth Wise

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Nitrogen dioxide is a prominent air pollutant produced by internal combustion engines burning fossil fuels as well as by a variety of industrial processes.  It is a toxic material associated with a number of respiratory illnesses. 

Researchers at the University of Manchester in the UK along with an international team of scientists have developed a new advanced material that can convert nitrogen dioxide from an exhaust gas stream into useful industrial chemical using only water and air.

The material is a metal-organic framework (or MOF) that provides a selective, fully reversible, and repeatable capability to capture nitrogen dioxide.  MOFs are tiny three-dimensional structures that are porous and can trap gases inside as though there were tiny cages.  MOFs have enormous amounts of surface area for their size.  One gram of material can have a surface area as large as a football field.

The material, named MOF-520, can capture nitrogen dioxide at ambient temperatures and pressures and even at low concentration and during flow in the presence of moisture, sulfur dioxide, and carbon dioxide.  Such conditions are typical of the exhaust of internal combustion engines. In fact, the process works best at the typical temperature of automobile exhausts.

Once the nitrogen oxide is absorbed, treating the material with water in air converts it into nitric acid and restores the MOF for additional use.  Nitric acid is the basis of a multi-billion dollar industry with uses including agricultural fertilizers, rocket propellant, and nylon.  Thus, there is great potential for recouping the costs of using the MOF technology and even profiting from it.

It would be great to convert a toxic pollutant into valuable industrial chemicals.

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Clean air research converts toxic air pollutant into industrial chemical

Photo courtesy of the University of Manchester.

Earth Wise is a production of WAMC Northeast Public Radio.

The Problem Of Gas Flaring | Earth Wise

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Gas flaring is the burning off of flammable gas released by pressure relief values during over-pressuring of plant equipment at petroleum refineries, chemical plants, natural gas processing plants, and a variety of oil and gas production plants.  Flaring is also used during plant startups and shutdowns.

A new study by Rice University concludes that reducing gas flaring would benefit both the environment and the economy. Flaring and venting of gas in West Texas’s Permian Basin and certain other parts of the U.S. have reached levels that the intended result of burning gas to allow oil extraction now looks more like wasting one resource to produce another.

At current rates, enough gas is flared in the Permian Basin to yield nearly 5 million metric tons of exportable liquid natural gas if it was captured and liquified.  At these rates, the wasted gas could fill the largest sized LNG carrier every ten days.  If that liquified natural gas was exported to China and used in a power plant, it would displace 440,000 metric tons of coal burned to generate electricity.

Burning natural gas to heat homes, power industrial processes, or generate electricity all emit carbon dioxide, but at least these things also perform valuable functions. Flaring gas produces CO2 as well as other combustion products but doesn’t even do anything useful.  The venting of unburned gas, which also takes place with some frequency, is even worse since it is dumping methane directly into the atmosphere.

Across the U.S., some 14.1 billion cubic meters of natural gas was flared in 2018, equivalent to nearly 9 million metric tons per year of LNG.  In energy terms, that is equivalent to more than one-third of the total LNG volume U.S. firms actually exported that year.

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Reducing gas flaring will benefit economy and environment, says Baker Institute expert

Photo courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Another Greenhouse Gas Record

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According to the World Meteorological Organization, levels of heat-trapping greenhouse gases in the atmosphere have reached yet another new record high.  Globally averaged concentrations of carbon dioxide reached 407.8 parts per million in 2018, up from 405.5 parts per million in 2017.

The increase year-over-year was similar to that from 2016 to 2017, and remains a little over the average for the last decade.  Global CO2 levels crossed the 400 parts per million threshold in 2015.

Concentrations of methane and nitrous oxide also increased by higher amounts than the average for the past decade, based on observations from the Global Atmosphere Watch network with stations all over the globe.

Since 1990, there has been a 43% increase in total radiative forcing – which is the warming effect on the climate from long-lived greenhouse gases. Carbon dioxide accounts for about 80% of this.  The report notes that the last time the Earth experienced this high a level of CO2 was 3 to 5 million years ago. At that time, global temperatures were 2 to 3 Celsius degrees higher and sea levels were 30 to 60 feet higher than now.

The report includes data on the isotopic analysis of the CO2 in the atmosphere.  CO2 produced by fossil fuel combustion comes from plant material from millions of years ago and does not contain radiocarbon, that is, carbon-14.  CO2 from natural sources contains radiocarbon produced by cosmic rays.  The increasing CO2 levels in the atmosphere contain decreasing levels of radiocarbon, indicating that the overall increase is largely due to human activities.

Overall, global efforts to date to reduce emissions have not been very successful, and this is borne out by the growing levels of carbon dioxide in the atmosphere.

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Greenhouse gas concentrations in atmosphere reach yet another high

Photo courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Carbon Capture As Big Business

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Removing greenhouse gasses from the atmosphere is an essential part of the overall effort to achieve zero net carbon emissions and stabilize the climate.  Since we have not been able to reduce emissions fast enough to do the job, it is important to find ways to pull carbon dioxide out of the atmosphere.

There are many ways to do it, but they tend to be rather expensive and, so far, the need to mitigate climate change does not seem to provide sufficient incentive. A new study by researchers at UCLA, the University of Oxford, and five other institutions, analyzed the possibility of creating a large global industry based on capturing carbon dioxide and turning it into commercial products.

The study investigated the potential future scale and cost of 10 different ways to use carbon dioxide, including in fuels and chemicals, plastics, building materials, soil management, and forestry.  The study looked at processes using carbon dioxide captured from waste products that are produced by burning fossil fuels as well as by simply capturing it directly from the atmosphere.  The study also looked at processes that use carbon dioxide captured biologically by photosynthesis.

The conclusions of the study were that on average each of the ten utilization pathways could use about half a billion tons of carbon dioxide that would otherwise escape into the atmosphere.  Thus, theoretically, these various pathways could take more than five billion tons of CO2 out of the atmosphere.   Currently, fossil fuel combustion emits about 40 billion tons of carbon dioxide.

The authors of the study stress that there is no silver bullet in the fight against climate change.  It will require multiple approaches – including CO2 removal for industrial use – to make real progress

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Carbon dioxide capture and use could become big business

Photo, posted September 18, 2015, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

SUVs And Carbon Emissions

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Global carbon dioxide emissions increased between 2010 and 2018.  The largest contributor to this increase was the power sector as electricity demand around the world continued to grow.   The second largest contributor to increased emission turns out to be SUVs, even while emissions for other cars actually decreased.

During that time period, SUVs more than doubled their global market share from 17% to 39% and their annual emissions rose to more than 700 million tons of CO2, which is more than the yearly total emission of the UK and the Netherlands combined.

This dramatic shift toward bigger, heavier SUVs has offset both efficiency improvements in small cars and savings from electric vehicles.  If SUV drivers were a nation, they would rank 7th in the world for carbon emissions.

SUVs are bigger, they are heavier, and their aerodynamics are poor.  As a result, it takes more gas to drive them.  They started to become popular in the 1980s – mostly in American suburbia – but now they have become globally popular.

The demand for SUVs is thought to be driven by perceptions of heightened safety or increased social status.  There is also the marketing and business strategy of manufacturers who obtain larger profit margins in the SUV segment.  Of course, for at least some consumers, the utility aspects of sport utility vehicles are actually important and not just the status.

For whatever reasons, SUVs are likely to be extremely popular for the foreseeable future as demand for sedans continues to decline.  Fortunately, electric SUVs are beginning to enter the market – including next year’s mass-market priced Tesla Model Y.  Such cars are the best solution to emissions from SUVs.

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Demand for SUVs a Major Contributor to the Increase in Global CO2 Emissions

Photo, posted May 9, 2017, courtesy of Yonkers Honda via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A New Way To Remove CO2 From The Air

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Researchers at MIT have developed a new way of removing carbon dioxide from a stream of air that could be a powerful tool in the battle against climate change.  The new system can pull carbon dioxide out of almost any concentration level of the gas, even including the roughly 400 parts per million level currently found in the atmosphere.

The technique is described in a new paper in the journal Energy and Environmental Science and is based on passing air through a stack of electrochemical plates. The device is essentially a large battery that absorbs carbon dioxide from the air passing over its electrodes as it is being charged up, and then releases the gas as it is being discharged.

To use it, the device would simply alternate between charging and discharging.  Fresh air or some other feed gas would be blown through the system during the charging cycle and then pure, concentrated carbon dioxide would be blown out during discharging.

The specialized battery uses electrodes coated with a compound called polyanthraquinone, which is composited with carbon nanotubes.  These unique electrodes have a binary affinity to carbon dioxide, which means that they either strongly want to capture carbon dioxide or not at all, depending upon whether the device is charging or discharging.

Carbon dioxide is important in many industries such as soft drinks and greenhouse agriculture.  With this device, the stuff could literally be pulled out of the air.  And, of course, in power plants where exhaust gas is dumped into the air, these novel electrochemical cells could be used to prevent the emission of CO2 into the atmosphere.  At the right price, this could be a game changer.

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MIT engineers develop a new way to remove carbon dioxide from air

Photo, posted August 9, 2007, courtesy of William Clifford via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Potential For Offshore Wind

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According to a new report from the International Energy Agency, offshore wind technology has vast potential for meeting our energy needs.  In total, offshore wind has the potential to generate more than 420,000 terawatt-hours of electricity each year, which is more than 18 times the global electricity demand that exists today.

Based on current policy targets and plummeting technology costs, offshore wind could increase 15-fold by 2040, becoming a $1 trillion industry and eliminating 5 to 7 billion tons of carbon dioxide emissions annually.

Offshore wind today generates just 0.3% of the world’s electricity, but its’ use is growing rapidly.  The industry has grown nearly 30% a year since 2010, and 150 new offshore projects are currently in development around the world.  The leading countries are in Europe – especially in the UK, Germany, and Denmark – but China is greatly expanding its offshore capacity and the US, India, Korea, Japan, and Canada are also expected to make large investments in offshore wind going forward.

Offshore wind is in a category of its own because it is considered a variable baseload power generation technology.  This is because the hourly variability of offshore wind is much lower than solar power or onshore wind.  Offshore wind typically fluctuates far less from hour-to-hour than the other variable energy sources.

Technology improvements and industry growth are driving steep cost reductions for offshore wind.  The cost of offshore wind is expected to be cut in half in the next five years, dropping to $60 per megawatt-hour, which is on par with solar and onshore wind and cheaper than new natural gas-fired capacity in Europe.

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Offshore Wind Has the Potential to Fulfill Global Electricity Demand 18 Times Over

Photo, posted August 9, 2016, courtesy of Lars Plougmann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Emissions From Natural Gas Processing

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Qatar, a small country in the Middle East with a population of about 2.5 million has the highest per capita income of any country in the world.  This is largely a result of being one of the world’s top producers of natural gas.  The upshot of that is that the tiny country has the dubious honor of being the world’s leading emitter of CO2 per capita.

Texas A&M University has a campus in Qatar and researchers there in collaboration with colleagues at the main campus in College Station, Texas have developed a new reactor technology that can help Qatar process its wealth of natural gas while reducing the country’s carbon footprint.

The technology processes natural gas and captured CO2 to produce both syngas – which is a valuable precursor for many products – and high-quality carbon nanotubes, all without releasing CO2 into the atmosphere.

Natural gas reforming is a process by which syngas – a feedstock for liquid hydrocarbons and ultraclean fuels- is produced.  The process requires lots of heat and emits CO2.  The new technology adds a novel CARGEN (or CARbon GENerator) reactor that advances the natural gas reforming process and includes a catalyst that captures the CO2 emissions and produces nanotubes.  The reactor can be driven by either electric or solar power, eliminating the need to burn fuel that ordinarily results in more carbon emissions.

The result is that Qatar’s CO2 emissions would be converted into two products that are important to its economy.  In particular, carbon nanotubes are very expensive and extremely versatile, and can be used to manufacture products such as computers and other high-quality materials.

The next step for the researchers is to partner with industry collaborators to further scale up the technology.

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Qatar Researchers Develop Natural Gas Processing Technology That Could Reduce Qatar’s Carbon Footprint

Photo, posted September 30, 2012, courtesy of Jimmy Baikovicius 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.

The Benefits Of Zero-Carbon Cities

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A new report issued by a coalition of 50 leading international institutions shows that low carbon initiatives in cities could reduce urban emissions by nearly 90% and support 87 million jobs worldwide by 2030.  The report finds that implementing low carbon measures in cities would be worth almost $24 trillion by 2050.

Cities are home to more than half the world’s population but produce 80% of gross domestic product and 75% of carbon emissions.  The research highlights the significant benefits carbon reduction can bring to cities in areas such as public health, job creation, and poverty alleviation.

The report shows that it is possible to cut 90% of emissions from cities using currently available technologies and practices including carbon savings from buildings, transportation, materials efficiency, and waste reduction.  Doing so would require an investment of nearly $2 trillion per year but would generate annual returns of nearly $3 trillion in 2030 and $7 trillion in 2050 based on cost savings alone.  Many low carbon measures would pay for themselves in less than five years, including more efficient lighting, electric vehicles, improved freight logistics, and solid waste management.

In addition to economic benefits, compact, connected and clean cities could provide a higher standard of living and greater opportunity for all.  These measures would also reduce air pollution, cut chronic traffic congestion, and improve worker productivity.

The report offers case studies from around the world where national and local governments have worked together to rapidly and profoundly transform their cities for the better within 20 or 30 years.

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The benefits of investing in zero-carbon cities

Photo, posted September 8, 2018, courtesy of Steffen Flor via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Electric Buses In Latin America

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Latin America has become increasingly urbanized.  In fact, about 80% of the region’s population lives in cities today and by 2050, that figure could climb to 90%.  Transportation is the largest and fastest-growing source of energy-related emissions in Latin America and accounts for about a third of all of the region’s carbon dioxide emissions. 

Private vehicle ownership is rising in Latin America but at the same time, the region’s rapidly growing cities have increased demand for buses, taxis, and motorcycles.  Currently, an estimated 64,000 people die prematurely every year in Latin America and the Caribbean as a result of air pollution, which is mostly caused by transportation emissions.

Given this situation, major cities across Latin America – from Colombia to Argentina – are starting to adopt electric bus fleets.   Latin America actually has the highest use of buses per person globally.  So, the transition to electric buses is an important step toward meeting climate targets, cutting fuel costs, and improving air quality.

Medellin, Colombia – whose metropolitan area has 3.7 million people – has started to add electric buses to its fleet, the rest of which runs on natural gas.  When new units arrive from China later this year, Medellin will have the second largest electric bus fleet in Latin America, after Santiago, Chile. 

Worldwide, 425,000 electric buses are in operation, 99% in China.  Europe has a couple of thousand while the United States has only 300.  But going forward, and especially in Latin America, electric buses are the wave of the future.  Estimates are that there will be 1.3 million on the roads by 2040.

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An Increasingly Urbanized Latin America Turns to Electric Buses

Photo, posted April 22, 2018, courtesy of Hans Johnson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Amazon And Climate Change

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Online shopping giant Amazon has unveiled a Climate Pledge, committing to meet the goals of the Paris climate agreement ten years ahead of schedule, and to be carbon neutral by 2040. This is the company’s most ambitious push yet to reduce its carbon footprint, which currently rivals that of a small country.  In fact, Amazon is responsible for 48.9 million tons of carbon dioxide last year, which is about 85% of what Switzerland typically emits in a year. 

Amazon, which ships more than 10 billion items a year on fossil fuel-intensive planes and trucks, has ordered a fleet of 100,000 electric vans that will start delivering packages to doorsteps in 2021.  The vans will be made by Rivian, a Michigan-based company that Amazon invested in earlier this year. 

Amazon plans to get 100% of its energy from solar and other renewable sources by 2030.  Currently, it gets about 40% of its energy from renewables. 

Amazon is also investing $100 million in nature-based climate solutions and reforestation projects around the world in order to remove carbon from the atmosphere. 

While announcing these initiatives recently at the National Press Club in Washington, D.C., Amazon CEO Jeff Bezos said the company needs to be a leader on the climate change issue:

We want to say look, if a company of Amazon’s complexity, scale, scope, physical infrastructure, delivering 10 billion items can do this, so can you.

After revealing Amazon’s Climate Pledge, Bezos said he would talk with CEOs of other large companies to try to get them to also sign it.  You can find a link to Amazon’s progress on its commitments by visiting this website.

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‘Middle of the herd’ no more: Amazon tackles climate change

Amazon: Committed to a sustainable future (track progress here)

Photo courtesy of Amazon.

Earth Wise is a production of WAMC Northeast Public Radio.

Emissions-Free Cement

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The production of cement – which is the world’s leading construction material – is a major source of greenhouse gas emissions, accounting for about 8% of global man-made emissions. 

Cement production produces carbon dioxide in two ways:  from a key chemical process and from burning fuel to produce the cement.  The process of making “clinker” – the key constituent of cement – emits the largest amount of CO2.  Raw materials, mainly limestone and clay – are fed into huge kilns and heated to over 2,500 degrees Fahrenheit, requiring lots of fossil fuel.  This calcination process splits the material into calcium oxide and CO2.  The so-called clinker is then mixed with gypsum and limestone to produce cement.

A team of researchers at MIT has come up with a new way of manufacturing cement that greatly reduces the carbon emissions.  The new process makes use of an electrolyzer, where a battery is hooked up to two electrodes in water producing oxygen at one electrode and hydrogen at the other.  The oxygen-evolving electrode produces acid and the hydrogen-evolving electrode produces a base.  In the new process, pulverized limestone is dissolved in the acid at one electrode and calcium hydroxide precipitates out as a solid at the other.

High-purity carbon dioxide is released at the acid electrode, but it can be easily captured for further use such as the production of liquid fuels or even in carbonated beverages and dry ice.  The new approach could eliminate the use of fossil fuels in the heating process, substituting electricity generated from renewable sources. 

The process looks to be scalable and represents a possible approach to greatly reducing one of the perhaps lesser known but nevertheless very significant sources of greenhouse gas emissions.

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New approach suggests path to emissions-free cement

Photo, posted March 26, 2014, courtesy of Michael Coghlan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Powerful Case For Protecting Whales

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Efforts to mitigate climate change typically face two major challenges.  One is to find effective ways to reduce the amount of atmospheric carbon dioxide.  The other is how to raise enough money to implement climate mitigation strategies. 

Many proposed solutions to climate change, like carbon capture and storage, are complex, expensive, and in some cases, untested.  What if there was a low-tech solution that was effective and economical?

Well, it turns out there is one, and it comes from a surprisingly simple, “no-tech” strategy to capture CO2: increase global whale populations. 

According to a recent analysis by economists with the International Monetary Fund, whales help fight climate change by sequestering CO2 in the ocean. 

Whales sequester carbon in a few ways.  They hoard it in their fat and protein-rich bodies, stockpiling tons of carbon apiece.  When whales die, they turn into literal carbon sinks on the ocean floor.  While alive, whales dive to feed on tiny marine organisms like krill and plankton before surfacing to breathe and excrete. Those latter activities release an enormous plume of nutrients, including nitrogen, iron, and phosphorous, into the water.  These so-called “poo-namis” stimulate the growth of phytoplankton, microscopic marine algae that pull CO2 out of the air and return oxygen to the air via photosynthesis.  Phytoplankton are responsible for every other breath we take, contributing at least 50% of all oxygen to the atmosphere and capturing approximately 40% of all CO2 produced. 

With other economic benefits like ecotourism factored in, economists estimate that each whale is worth $2 million over its lifetime, making the entire global population possibly a one trillion dollar asset to humanity.

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How much is a whale worth?

Photo, posted June 12, 2013, courtesy of Gregory Smith via Flickr.

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A New Kind Of Coral Nursery

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Coral reefs around the world are struggling from warming waters and increasing ocean acidification driven by excess carbon dioxide.  Many of the world’s greatest reefs – such as Australia’s Great Barrier Reef – have seen steep declines over the past decade.

But apart from the global environmental threat, reefs also are often damaged by various marine accidents such as ships grounding on them.   Such events can severely damage a reef and scatter countless small coral fragments onto the seafloor.  These small pieces of coral are not actually dead; they can continue on with their lives if they are relocated to a suitable environment such as a coral nursery.

Coral nurseries are generally small installations that allow coral fragments – typically pieces about 4 inches in length – to recover from their reef breaking up and to grow until they are large enough for conservation managers to replant them into reefs that need them.  This strategy works well in places where corals grow relatively quickly – such as Florida and the Caribbean – but not as well in places where coral grows more slowly, such as Hawaii.

Recently, coral experts at the National Oceanic and Atmospheric Administration working with mechanical engineering students at the University of Hawaii have developed a new type of coral nursery that can save fully formed coral colonies as opposed to small coral fragments.

The nurseries are large, carefully designed structures that can be loaded up with corals that have become detached from their reefs.  Some of these new structures were installed in the waters of Oahu in the summer of 2018 and were populated with corals.  The relocated corals, which would have otherwise died, are now recovering nicely in their new coral daycare centers and will soon be replanted back into the reef.

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NOAA Develops A New Type of Coral Nursery

Photo, posted July 29, 2010, courtesy of Kyle Taylor via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

New Membranes For Carbon Capture

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Drastically reducing the amount of carbon dioxide being emitted into the atmosphere is an essential goal in the effort to mitigate the effects of climate change.  While the ultimate solution is to avoid combustion of fossil fuels by the use of clean alternative energy sources, that transition will take time – possibly more time than we have.  As a result, there is a great deal of effort underway to develop techniques for capturing the carbon emitted by fossil fuel combustion and either recycling it or storing it.

There are multiple ways to capture carbon emissions, but the ultimate goal is to find a technique that is both inexpensive and scalable.  One promising technique involves the use of high-performance membranes, which are filters that can specifically pick out CO2 from a mix of gases, such as those coming out of a factory smokestack.

Scientists at a Swiss laboratory have now developed a new class of high-performance membranes that exceeds the targeted performance for carbon capture by a significant margin.  The membranes are based on single-layer graphene with a selective layer thinner than 20 nanometers – only about 40 atoms thick. The membranes are highly tunable in terms of chemistry, meaning that they can be designed to capture specific molecules.

The membranes are highly permeable – meaning that they don’t impede gas flow too much – but highly selective.  The CO2/N2 separation factor is 22.5, which means that 22.5 times more nitrogen can get through the membrane than carbon dioxide.

The work is just at the laboratory stage at this point, but it is a very promising step towards developing a practical scheme for keeping carbon dioxide from escaping from power-plant and factory smokestacks.

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Next-gen membranes for carbon capture

Photo, posted December 28, 2010, courtesy of Emilian Robert Vicol via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The State Of The Climate

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The federal government has issued the annual State of the Climate report and it is a sobering one.  The report states that carbon dioxide in the atmosphere rose to levels the world has not seen in at least 800,000 years.  Global carbon dioxide concentrations reached a record 407.4 parts per million during 2018.  That is 2.4 ppm more than 2017.

Other greenhouse gases like methane and nitrous oxide also continued their rapid increase.  Taken together, the global warming power of greenhouse gases was 43% stronger than it was in 1990.

Along with greenhouse gases, global sea levels also reached their highest levels on record for the seventh consecutive year.  Ocean levels are rising about an inch per decade, but that number may rise if ice melt at the poles continues to accelerate.

Global temperatures had their fourth highest level on record in 2018, slightly lagging 2016, 2015, and 2017 for the highest ever.  A La Niña over the Pacific cooled ocean waters for part of 2018, keeping temperatures a bit lower.  So far, 2019 is on track to be the warmest year in recorded history.

Global sea temperatures also set a record level in 2018.  And glaciers continued to melt at an alarming rate for the 30th consecutive year.

The State of the Climate report is yet another in a series of expert, science-based reports that continue to sound the alarm about the climate crisis.  Climate change is affecting our weather, agricultural productivity, water supply, public health and national security.  Unfortunately, the facts continue to be drowned out for many people by blogs, pundits, and posts on social media.

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Greenhouse Gases Reach Unprecedented Level

Photo, posted January 13, 2014, courtesy of Ronnie Robertson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wildfires And Carbon

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This summer has been an unprecedented year for fires in the Arctic.  Major fires have burned throughout the Arctic in Russia, Canada, and Greenland.  In total these fires released 50 million tons of carbon dioxide in June alone, which is as much as Sweden emits in an entire year.

In an average year, wildfires around the world burn an area equivalent to the size of India and emit more carbon dioxide to the atmosphere than global road, rail, shipping and air transport combined.

Ordinarily, this is part of a natural cycle.  As vegetation in burned areas regrows, it draws CO2 back out of the atmosphere through photosynthesis.  This is part of the fire-recovery cycle, which can take less than a year in grasslands, but decades in forests.  But in Arctic or tropical peatlands, full recovery may not occur for centuries.

A recent study looked at and quantified the important role that charcoal plays in helping to compensate for carbon emissions from fires.  In wildfires, some of the vegetation is not consumed by burning, but instead is transformed to charcoal – referred to as pyrogenic carbon.   This carbon-rich material can be stored in soils and oceans over very long time periods.

Researchers have combined field studies, satellite data, and modelling to quantify the amount of carbon that is placed in storage in the form of charcoal.  Their results are that the production of pyrogenic carbon amounts to about 12% of the CO2 emissions from fires and can be considered a significant buffer for landscape fire emissions.

Charcoal does not represent a solution to the problem of increasingly intense wildfires, but it is important to take it into account in understanding what is happening.

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How wildfires trap carbon for centuries to millennia

Photo, posted August 17, 2018, courtesy of the Bureau of Land Management Oregon and Washington via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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