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The Dangers Of Negative Emissions Technologies | Earth Wise

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Reducing carbon emissions is not easy and there are plenty of people who don’t even want to try for various reasons, generally related to their perceived economic interests and convenience.  As a result, there is a great deal of interest in so-called negative emissions technologies or NETs.   These are methods for removing carbon dioxide from the atmosphere.  Even the UN Intergovernmental Panel on Climate Change assumes that NETs will play a role in mitigating the effects of climate change and meeting international goals.

The most widely studied approaches to negative emissions technology are bioenergy with carbon capture and storage – which entails growing crops for fuel, and then capturing and burying the CO2 produced from burning the fuel; planting more forests; and direct air capture, which involves actually pulling CO2 out of the air and storing it – probably underground. 

A new study published in Nature Climate Change points out that none of these technologies has even been tried at the demonstration scale, much less at the massive levels required to make a dent in current CO2 emissions. 

Their analysis of the biofuel and reforestation strategies show that each would take up vast land and water resources already needed for agriculture and nature.  Air capture uses less water than the other two approaches, but still uses quite a bit and even more energy, which if supplied by fossil fuels, would offset the benefits of carbon capture.

Negative emissions technologies may well play an important role in combating climate change, but it is essential that we understand what the consequences will be from implementing them.  We need to know the pitfalls that could arise.  It would be a major mistake to simply count on NETs to be some kind of silver bullet.

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Remove CO2 from the air? Don’t bet on it before examining costs, researchers say

Photo, posted January 11, 2008, courtesy of Al Pavangkanan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Greenland Glaciers Past The Point Of No Return | Earth Wise

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Forty years of satellite data from Greenland shows that the glaciers on the island have shrunk so much that even if global warming came to an abrupt halt, the Greenland ice sheet would continue to shrink.

This conclusion was published in the journal Communications Earth and Environment by researchers at Ohio State University.  According to their study, Greenland’s glaciers have passed a tipping point where the snowfall that replenishes the ice sheet each year can no longer keep up with the ice that is flowing into the ocean from the glaciers.

The study analyzed monthly satellite data from more than 200 large glaciers that drain into the ocean around Greenland.  It looked at how much ice breaks off into icebergs or melts from the glaciers into the ocean as well as the amount of snowfall each year that replenishes the glaciers.

Throughout the 1980s and 90s, these two processes were mostly in balance, keeping the ice sheet intact.  But the amount of ice being lost each year started to increase steadily around the year 2000 while there was no increase in snowfall.   Both processes fluctuate from year to year, but the baseline for ice loss has steadily risen.  Before 2000, the Greenland ice sheet had about the same chance of gaining or losing mass each year.  At this point, the ice sheet is likely to gain mass in only one out of every 100 years.

Large glaciers in Greenland have retreated about 2 miles since 1985, so that many of them are sitting in deeper water with more ice in contact with warmer water making it harder for glaciers to grow back.  At this point, even if the climate reverses its trend, the ice sheet will continue to lose mass.

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Warming Greenland ice sheet passes point of no return

Photo, posted August 27, 2015, courtesy of Joxean Koret via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Artificial Aquatic Polyps | Earth Wise

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Corals are often mistaken for rocks because of their hardened surfaces.  And, since they attach or “take root” to the sea floor, they are often mistaken for plants.  But unlike rocks, corals are alive.  And unlike plants, corals do not make their own food.  Corals are actually animals. 

Most of these structures that we call “coral” are made up of hundreds to thousands of tiny coral creatures called polyps.  A coral polyp, which is often no thicker than a nickel, has a saclike body and mouth that is encircled by stinging tentacles.  Polyps are responsible for a host of ecosystem services, including nourishing corals, and aiding coral survival by generating self-made currents through the motion of their soft bodies. 

Inspired by these marine organisms, researchers from the University of Warwick in the UK and Eindhoven University of Technology in the Netherlands have collaborated to develop an artificial aquatic polyp capable of removing contaminants from water.  The 1 square centimeter wireless robot polyp can attract, grasp, and release objects, moving under the influence of a magnetic field and whose “tentacles” are triggered by light. 

The next step for the researchers is to see if the technology can be successfully scaled up from laboratory to pilot scale.  In order for that to happen, the team has to design an array of artificial polyps capable of working harmoniously together.   

Corals are an incredibly important part of ocean ecosystems.  And while it remains to be seen how much value artificial polyps can achieve in future applications, it serves as another example of scientists emulating nature to create more sustainable designs. 

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Aquatic robots can remove contaminant particles from water

An artificial aquatic polyp that wirelessly attracts, grasps, and releases objects

Photo, posted April 14, 2011, courtesy of Derek Keats via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Generating Hydrogen From Poor-Quality Water | Earth Wise

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Hydrogen could be the basis of a complete energy system.  It could be stored and transported and could be used to power vehicles and to generate electricity in power plants.  Proponents of the so-called hydrogen economy contend that hydrogen is the best solution to the global energy challenge.  But among the challenges faced by a hydrogen economy is the development of an efficient and green method to produce hydrogen.

The primary carbon-free method of producing hydrogen is to break down water into its constituent elements – hydrogen and oxygen.  This can be done in a number of ways, notably by using electricity in a process called electrolysis.  A method that seems particularly attractive is to use sunlight as the energy source that breaks down the water molecule.

While there is an abundance of water on our planet, only some of it is suitable for people to drink and consume in other ways.    Much of the accessible water on earth is salty or polluted.  So, a technique to obtain hydrogen from water ideally should work with water that is otherwise of little use to people.

Researchers in Russia and the Czech Republic have recently developed a new material that efficiently generates hydrogen molecules by exposing water – even saltwater or polluted water – to sunlight. 

The new material is a three-layer structure composed of a thin film of gold, an ultra-thin layer of platinum, and a metal-organic framework or MOF of chromium compounds and organic molecules.  The MOF layer acts as a filter that gets rid of impurities.

Experiments have demonstrated that 100 square centimeters of the material can generate half a liter of hydrogen in an hour.  The researchers continue to improve the material and increase its efficiency over a broad range of the solar spectrum.

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New Material Can Generate Hydrogen from Salt and Polluted Water

Photo courtesy of Tomsk Polytechnic University.

Earth Wise is a production of WAMC Northeast Public Radio.

A Fabric To Keep You Cool | Earth Wise

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About 10% of all electricity consumption in the U.S. is devoted to keeping us cool with air conditioning and other methods.  Researchers at two universities in Shanghai, China have developed a new material that can be made into clothing that cools the wearer without using any electricity.

The new fabric transfers heat, allows moisture to evaporate from the skin, and repels water.  Cooling off a person’s body is much more efficient than cooling off an entire room or a building.  There have been textiles and types of clothing designed to perform the cooling function, but most of those have disadvantages.  These include some combination of poor cooling capacity, high energy consumption, complex and time-consuming manufacturing, and high cost.

The researchers wanted to develop a personal cooling fabric that can efficiently transfer heat away from the body while at the same time being breathable, water resistant and easy to make.

The new fabric is made by electrospinning an ordinary polyurethane polymer with a water-repelling fluorinated version of polyurethane polymer along with a thermally conductive filler composed of boron nitride nanosheets.  The resultant material is a nanofibrous membrane that repels water from the outside but has large enough pores to allow sweat to evaporate from the skin and air to circulate. 

Tests of the membrane demonstrated higher thermal conductivity than other conventional or high-tech fabrics.  Used in clothing, the material would be more effective than previous fabrics in conducting heat away from the body. It may be possible to beat the heat without turning on the AC.   These membranes could also be useful for solar energy collection, seawater desalination, and thermal management of electronic devices.

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New fabric could help keep you cool in the summer, even without A/C

Photo courtesy of the American Chemical Society on Youtube.

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.

Green Bills Pass In New York | Earth Wise

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In late July, the two houses of the New York legislature passed a number of environmental bills covering a wide range of topics.

These included a bill to add protected status for streams that support fisheries and non-contact recreation.  A second bill bans the use of PFAS in food packaging.  A third bill classifies all wastes resulting from oil and gas exploration, development, extraction or production as hazardous waste, closing a previous loophole in the law.

A fourth bill requires water works corporations with more than 1,000 service connections to post their annual water supply statements online, thereby providing transparency and openness to water quality data.  A fifth bill expands protections for endangered species to protect them from environmental rollbacks by the federal government.

A sixth bill prohibits non-electric vehicles from parking in spaces designated for electric vehicle charging, thereby establishing penalties for this practice that is often done for spite.  A seventh bill bans the use of glyphosate – the herbicide found in Roundup and other products – on state property.

An eighth bill reduces the use of road salt in the Adirondacks.  A ninth bill requires supermarkets to make good faith efforts to donate edible excess food to qualifying entities such as food pantries, food banks, or similar entities.   A tenth bill bans certain uses of trichloroethylene or TCE, including as a vapor degreaser, an intermediate chemical to produce other chemicals, a refrigerant, or an extraction solvent.

When signed by the governor, these ten pieces of legislation will help protect New York’s environment, water, and health.  It was a busy session for green legislation.

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Several Green Bills Pass in State Legislature

Photo, posted September 12, 2018, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Conserving The Colorado River | Earth Wise

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Last year, we talked about the troubles facing the Colorado River.  Nearly two decades of drought conditions have reduced the water levels of the two largest reservoirs of Colorado River water and have threatened the water supply of millions of people in the region.  Clear scientific evidence shows that climate change is constricting the iconic river and will do further damage as temperatures rise.

Faced with these facts, water resource managers have been implementing conservation policies in the region and the results so far are very encouraging.

The use of Colorado River water in the three states of the river’s lower basin – Arizona, California, and Nevada – fell to a 33-year low in 2019.  The three states consumed just over 6.5 million acre-feet for the year, which is about 1 million acre-feet less than the three states are entitled to use under the legal agreement that allocates Colorado River water.

The last time water consumption from the river was that low was in 1986, which is the year that Arizona opened a large canal that extracts river water for its entitlement. 

A key indicator of river health is the depth of Lake Mead, the largest reservoir of Colorado River water.  It has been steadily dropping in recent years, but last year, with the reduced consumption, the water level actually increased by 12 feet.

According to water managers, the steady drop in water consumption in recent years is a sign that conservation efforts are working and that there are strategies that can deal with chronic shortages on the river in the future.  It represents an important demonstration that it is possible to use less water in a region that irrigates 5 million acres of farmland and has 40 million people in 2 countries and 29 tribal nations.

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Remarkable Drop in Colorado River Water Use a Sign of Climate Adaptation

Photo, posted July 7, 2015, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Beavers And The Warming Arctic | Earth Wise

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Beavers have a remarkable ability to transform landscapes.  Using their sharp teeth, they fell trees and shrubs and build dams, which cause small valleys to fill with water and form new lakes.  Some of these lakes measure five or ten acres in size, or even more.  And beavers are very efficient builders; they often build their dams at precisely those points where can they have the greatest effect with the least effort.

Scientists studying beaver activity in the Arctic regions of Alaska have found that the changing climate is leading to a substantial increase in beaver populations and their effect on the landscape.

In 2018, researchers found that the beavers living in a 7,000 square-mile area in northwest Alaska had created 56 new lakes in just five years.  Thanks to rising temperatures, more and more habitats offer the shrubs that beavers need for food and building material.  In addition, the lakes, which used to freeze solid, now offer beaver-friendlier conditions.  Also, beavers are not hunted as intensively as in the past.

The scientists were surprised that beavers have seized the opportunity so intensively.  There is basically an exponential growth in beaver dams.  This is actually a worrisome situation.  Forming all these new lakes degrades ice-rich permafrost in the area.  In the Kotzebue region of Alaska, the overall water area has increased by more than 8% over the past 17 years, and roughly two-thirds of that is due to beavers.

The degradation of the Arctic’s permafrost is a dangerous situation and it appears that anyone who wants to predict its future has to keep the activity of beavers in mind.

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Beavers gnawing away at the permafrost

Photo, posted June 23, 2018, courtesy of Becky Matsubara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Preserving Produce With Eggs | Earth Wise

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Researchers at Brown University have developed an inexpensive coating to protect fruits and vegetables that is made from eggs that would otherwise be wasted.  The micron-thick coating solves problems for the produce and its consumers as well as for the environment.

The coating relies on eggs that never reach the market.  The U.S. produces more than 7 billion eggs a year.  The supply chain rejects about 3% of them, typically because of shell damage, which means that more than 200 million eggs end up in landfills.

The coating is mostly made from egg, the rest consisting of nanoscale cellulose extracted from wood, a tiny amount of curcumin (the main active ingredient in turmeric that has antimicrobial properties), and a bit of glycerol for added elasticity.  The coating is applied to produce by spraying or dipping.  It shows a remarkable ability to resist rotting for an extended period comparable to standard coatings like wax, but without their shortcomings.

Along with being edible, the coating retards dehydration, provides antimicrobial protection, and is largely impermeable to both water vapor to prevent dehydration and to gas to prevent premature ripening.  The coating is entirely natural, and it washes off with water.  So, anyone sensitive to the coating, such as someone with an egg allergy, can easily eliminate it.

Lab tests of the coating studied its effects on strawberries, avocados, bananas and other fruits.  All were seen to maintain their freshness far longer than uncoated produce.

The researchers are continuing to refine the coating.  They are also considering other source materials.  They chose egg proteins because there are so many wasted eggs, but it may be possible to make use of plant proteins instead to address the needs of vegan consumers.

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Egg-based coating preserves fresh produce

Photo, posted July 13, 2012, courtesy of Liz West via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Nanotech Water Purification | Earth Wise

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We have occasionally talked about metal-organic frameworks, which are organic-inorganic hybrid crystalline structures that have a microscopic cage-like structure.  MOFs have been under development for a diverse set of applications including gas storage and separation, liquid purification, energy storage, catalysis, and sensing.

For the first time, an international research team, led by researchers from Monash University in Australia, has created an ultrathin porous membrane based on MOF technology that can completely separate potentially harmful ions, such as lead and mercury, from water.

This innovation could enhance water desalination and transform even the dirtiest water into something potable for millions of people around the world.  The new membrane performed steadily in tests for more than 750 hours using only limited energy.

The technology uses water-stable monolayer aluminum-based MOFs just a millionth of a millimeter in thickness.  These are essentially two-dimensional structures.  The ultrathin membrane is permeable to water – it achieves maximum porosity – but rejects nearly 100 percent of ions.  It has been a daunting challenge to fabricate ultra-thin MOFs for water-based processing.  Most previous membranes were too thick and unstable in water. 

Most existing ion separation membrane technologies are based on polymers and have the limitation that they have limited selectivity.  They don’t reject all unwanted ions.

The new membrane technology has great potential based on its precise and fast ion separation and could be ideal for a variety of filtration applications such as gas separation and separation of organic solvents such as paint.  Such membranes might also be used to remove harmful carcinogens from the atmosphere.

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Ultrathin nanosheets separate ions from water

Photo courtesy of Monash University.

Earth Wise is a production of WAMC Northeast Public Radio.

Mangrove Trees And Climate Change | Earth Wise

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Mangrove trees are small trees that grow in coastal saline or brackish water at tropical and subtropical latitudes.  Many mangrove trees can be identified by their dense tangle of prop roots.  These roots make the trees appear as if they are standing on stilts above the water.  The tangle of roots allows mangrove trees to handle the daily rise and fall of tides and to slow the movement of tidal waters.  

Mangrove forests provide many ecosystem services, including stabilizing the coastline by reducing erosion from storm surges, waves, and tides.  The intricate root system of mangrove trees are attractive to fish and other species seeking food and shelter from predators.  Mangrove forests also store large amounts of carbon.     

But according to a new study recently published in the journal Science, mangrove trees won’t survive sea level rise by 2050 if greenhouse gas emissions aren’t reduced.  

Using sediment data from 78 locations over the last 10,000 years, an international team of scientists led by Macquarie University in Australia estimated the chances of mangrove trees survival based on the projected rates of future sea-level rise.

When sea level rise rates exceeded 6 millimeters per year, which is similar to estimates under high-emissions scenarios for 2050, researchers found that mangrove trees were unlikely to keep pace with the rising water levels.  But when the annual increase was 5 millimeters or less – which is the projected low-emissions scenario this century – mangrove trees are much more likely to survive. 

These findings underscore the importance of reducing greenhouse gas emissions to mitigate rapid sea level rise.  The future of mangrove trees may depend on it.  

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Mangrove trees won’t survive sea-level rise by 2050 if emissions aren’t cut

Photo, posted December 17, 2012, courtesy of Edward Stojakovic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Making Use Of Invasive Seaweed | Earth Wise

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In recent years, millions of tons of brown Sargassum seaweed have formed gigantic blooms stretching all the way across the Atlantic Ocean from West Africa to the Gulf of Mexico.  The seaweed has become a problem for shorelines in the Caribbean, the Gulf of Mexico, and the east coast of Florida.  The massive increase in seaweed populations is related to changes in ocean chemistry resulting from nutrients from fertilizer use entering the water as well as from changes to the climate affecting ocean currents and temperatures.  The seaweed is harming the tourism industry as well as fisheries and ocean ecosystems.

Cleaning up the seaweed that washes ashore is labor-intensive and therefore expensive.  A research team led by two British universities has developed a cheap and simple way to pre-process seaweed to facilitate making it into bulk chemicals and biofuels.  With the new process, cleaning up the seaweed can be both economically and environmentally viable.

Previous techniques for processing seaweed generally required removing it from the saltwater, washing it in fresh water, and drying it – all of which add significant costs.  The new technique makes use of catalysts to release sugars from untreated seaweed that feed a yeast to produce a palm oil substitute.  At the same time, the process creates heat and pressure, turning the residual materials into a bio-oil that can be processed further into fuels, and a high-quality, low-cost fertilizer.

Apart from getting economic value out of the seaweed that is collected, any plastic collected alongside the seaweed can be converted to useful materials as well. 

It appears that the seaweed scourge is here to stay, so finding an economically viable way to deal with it is a welcome development.

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Solve invasive seaweed problem by turning it into biofuels and fertilisers

Photo, posted August 10, 2015, courtesy of Flickr.

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.

Keeping Charleston Dry | Earth Wise

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Charleston, South Carolina is visited by millions of tourists each year.  The town is a glimpse into the past, showcasing antebellum mansions, row houses, historic African American churches and scenic harbor views from a Civil War-era promenade.

Charleston is also visited more and more by water from rising seas and increasingly powerful storms.  The city is essentially drowning in slow motion and may soon face an existential threat to its survival.

Charleston has a harbor and three rivers and water from all these sources leaks in at every bend and curve, fills streets, disrupts businesses, and rushes into homes during storms.  Million-dollar antebellum mansions, built on spongy marsh and old tidal creeks, flood repeatedly.

City officials have endorsed a plan by the U.S. Army Corps of Engineers to wall off the historic downtown with an 8-mile-long seawall that would cost nearly $2 billion.  The proposed barricade is just one of many proposed projects to build seawalls, surge gates, levees, and other barriers to defend U.S. coastal cities in an era of rising seas and climate-fueled floods and storms.  A proposed flood wall in Miami would cost federal taxpayers $8 billion.

Researchers generally agree that sea levels are likely to rise by at least 3 feet by the end of the century.  Some experts believe the rise will be much greater.  So, a key question is whether these barriers will actually keep out the water.  Critics of many of the proposed solutions contend that they are doomed to fail.

Flooding has caused nearly $1 trillion worth of damage along the East and Gulf coasts over the past 40 years.  And things are almost certain to get worse in Charleston and other coastal cities.

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Fortress Charleston: Will Walling Off the City Hold Back the Waters?

Photo, posted October 7, 2015, courtesy of Jeff Turner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Planting Trees and Climate Change | Earth Wise

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Forests are among the most important natural carbon sinks.  Trees remove carbon from the air and store it in their trunks, branches, and leaves, and transfer part of it into the soil.  But in some regions, these natural carbon sinks are starting to weaken due to deforestation, forest degradation, and the impacts of climate change.  This problem has led some climate mitigation projects to focus on increasing the overall number of trees on the planet. 

But, according to a paper recently published in the journal Science, “we can’t plant our way out of climate change.”  That’s the simple message from Restoration Ecologist Karen Holl and University of São Paulo Professor Pedro Brancalion to anyone who thinks planting one trillion trees will reverse the effects of climate change.  They say planting more trees is only one piece of the puzzle.  Any initiatives like 1t.org or the Trillion Tree Campaign must be done carefully and be accompanied by commitments to long-term management.

Tree plantings can provide many environmental benefits, including improving water quality, biodiversity, and increasing shade.  But trees can sometimes have undesirable impacts, such as harming native species and ecosystems or reducing water availability, depending on where and how the trees are planted.

The authors suggest four principles that should guide forest enhancement initiatives: reduce forest clearing and degradation, balance ecological and social goals, view tree plantings as one part of a multifaceted solution, and plan, coordinate and monitor the work. 

While tree plantings can clearly be part of the solution, slowing the pace of climate change requires a comprehensive approach that must start with burning less fossil fuels.

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Challenges in tree-planting programs

Planting trees is no panacea for climate change

Photo, posted December 1, 2019, courtesy of Akuppa John Wigham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recovering Marine Life By 2050 | Earth Wise

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Marine life has faced challenges for a long time.   There have been centuries of overfishing in many places and pollution of various types has been especially harmful in recent decades.   But despite all of this, a new scientific review published in the journal Nature contends that marine life in the world’s oceans could be fully restored in as little as 30 years provided that aggressive conservation policies are adopted.

The research spotlights the strong resiliency of ocean animals and cites the successful recovery of a number of marine species, including humpback whales.

The study indicates that nations around the world must agree to designate 20 to 30 percent of the oceans as marine protected areas, institute sustainable fishing guidelines, and regulate pollution.  These measures would not come cheaply.  The estimated cost would be around $20 billion a year. 

However, the report also estimates that the economic return on this investment would be tenfold and would create millions of new jobs.  Rebuilding fish stocks and maintaining sustainable fishing policies could increase global profits of the seafood industry by over $50 billion a year.  Conserving coastal wetlands could save the insurance industry more than $50 billion a year as well by reducing storm damage.

A major sticking point, however, is climate change.  Climate change is increasing ocean temperatures and driving acidification.  Unless these changes are brought under control, the restoration of marine life is not going to be successful.  We have reached the point where it is within our power to choose between a future with a resilient and vibrant ocean or an irreversibly disrupted ocean.  Whether we embrace that challenge remains to be seen.

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Marine Life Could Recover By 2050 With the Right Policies, Study Finds

Photo, posted April 20, 2012, courtesy of Matthias Hiltner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting Fresh Produce | Earth Wise

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Fresh fruits and vegetables can sometimes become contaminated by microorganisms during their long journey from fields to restaurants and grocery stores.  Contaminated produce can spoil other produce, which increases the number of fruits and vegetables in the supply chain that can cause illnesses. 

In order to prevent this cross-contamination between produce, researchers from Texas A&M University have designed a coating that can be applied to food-contact surfaces, like buckets, rollers, and conveyor belts.  The newly-created dual-function coating is both water-repellent and germicidal.  In other words, it can both repel and kill.  Without water, the researchers say bacteria can’t stick or multiply on surfaces, drastically reducing contamination.

To make this dual-function coating, the researchers chemically-attached a thin layer of silica to an aluminum sheet.  They then added a mixture of silica and lysozyme, a naturally-occurring germicidal protein found in egg whites and tears.  Together, the silica-aluminum and the silica-lysozyme formed microscopic bumps and crevices.  According to the research team, this rough texture, albeit microscopic, is the key to the coating’s superhydrophobic properties.  

The researchers tested the coating’s effectiveness at curbing the growth of two strains of disease-causing bacteria:  Salmonella and Listeria.  Upon review, the number of bacteria found on the dual-coating surfaces was 99.99% less than what was found on the uncoated surfaces. 

Despite the success in preventing bacterial spread, the research team said more research needs to be done to see how well the coating works for mitigating viral cross-contamination.  Since the coating would need to be reapplied after a certain amount of use, the researchers also plan to develop more permanent, dual-function coatings. 

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New dual-action coating keeps bacteria from cross-contaminating fresh produce

Photo, posted April 14, 2012, courtesy of U.S. Department of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Conservation In Vermont | Earth Wise

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In recent times, Vermont and neighboring states have been losing forest land to development at a rate of almost 1,500 acres per year.  With forest fragmentation gaining ground across New England, conserving land for future generations of people, wildlife, and plants has become both increasingly important and increasingly difficult.

According to a new study published by researchers at the University of Vermont, the state has already protected a third of the highest priority targeted lands needed to protect and connect valuable wildlife habitats and corridors.  The protected lands amount to 1.3 million acres.

Most of the currently conserved lands are forested.  However, there are high-priority targeted surface water and riparian areas – ponds, rivers, shorelines, and wetlands – and not nearly enough of these have been protected.  (Many animals require zones along waterways in which to travel between the habitats they need to survive).

The state of Vermont and a number of partners have laid out a comprehensive and thoughtful vision that would ensure that Vermont remains a good place for all forms of life in the future.  The new study provides a crucial benchmark of current levels of forest protection to help prioritize future conservation actions. 

Three groups dominate in responsibility for the state’s protected lands:  the federal government, the state government, and private non-profit organizations.  (Each of these account for roughly a third of existing protected lands).

Going forward, Vermont’s nonprofits will play an increasingly important role in land conservation, especially in continuing to protect those areas that are rich with species diversity.  Nonprofits are engaging more and more deeply in restoring wetlands that were previously degraded, planting new forests along river shores, and protecting unique natural communities while also protecting working forests and farmland.

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Vermont Has Conserved One Third of the Land Needed for an Ecologically Functional Future

Photo, posted June 15, 2014, courtesy of Wesley Carr 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...)