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Keeping Trash Out Of The Ocean | Earth Wise

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The Ocean Cleanup is a non-profit organization, founded in 2013 by Dutch inventor Boyan Slat, to develop and scale technologies to rid the world’s oceans of plastic.  It is an organization that proudly declares that its primary aim is to put itself out of business by successfully cleaning up the oceans.

A major activity of The Ocean Cleanup is efforts to clean the ocean garbage patches that have accumulated in several places, best-known of which is the Great Pacific Garbage Patch.  The effort involves use of large U-shaped floating barriers that act as an artificial coastline to trap garbage which is then funneled into a barge for disposal.  Ten full-sized systems will be needed to clean up the Great Pacific Garbage Patch.

A second activity of The Ocean Cleanup is preventing garbage in rivers from making its way into the oceans.  Rivers are the main source of ocean plastic pollution.  The Ocean Cleanup has developed river machines called Interceptors that capture garbage for disposal.  Last fall, they installed a machine called Interceptor 007 in Ballona Creek, a waterway in the Los Angeles area.  In the first rainfall after installation, the Interceptor managed to stop 35,000 pounds of waste from entering the ocean in just a few days.

The original Interceptor models have been deployed in Indonesia, Malaysia, the Dominican Republic, and Vietnam. A different type called the Interceptor Trashfence is being tested in Guatemala.

The Ocean Cleanup states that if fleets of its barrier systems are installed in all the garbage patches and Interceptors in the 1000 most significant rivers, 90% of floating ocean plastic can be removed by 2040.

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The Interceptor 007 Stops 35,000 Pounds Of Trash From Entering Ocean

The Ocean Cleanup

Photo, posted February 23, 2015, courtesy of Ministerie van Buitenlandse Zaken via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Reef Insurance | Earth Wise

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Coral reefs around the world face multiple dangers from warming waters, acidification, human activity, and more.  Powerful storms often cause tremendous damage to reefs.  When possible, snorkelers and divers are deployed to try to repair damage to reefs.  But philanthropy and government grants are basically the only resources available to fund such actions.

Three years ago, tourist businesses and the government in the Mexican state of Quintana Roo purchased an insurance policy to offset costs of protecting the local parts of the Mesoamerican Reef.  The environmental group the MAR Fund later took out an insurance policy on the rest of the reef in Mexico, Belize, Guatemala, and Honduras. 

With this precedent, the Nature Conservancy recently purchased an insurance policy on behalf of the state of Hawaii to help offset repair work on its coral reefs.  It is the first U.S. coral insurance contract.

Coral reefs are more than just hosts for marine life.  They provide barriers against ocean storm surges, which is a major financial incentive for protecting them and hence an incentive to invest in insurance.

The new Hawaiian insurance policy has a premium of $110,000 a year and will provide $2 million in protection.  Payouts occur when wind speeds go above 50 knots.  No further proof of damage is required.

The Nature Conservancy has created teams called ‘Reef Brigades’ composed of snorkelers and divers who recover reef fragments, store them in ocean or shore-based nurseries, and then re-attach them when conditions are safe.  It can be very expensive to do this sort of work, particularly when new corals grown in a nursery are required.

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Analysis: First U.S. coral insurance marks the rise of the reef brigades

Photo, posted September 14, 2011, courtesy of Greg McFall/NOAA Office of National Marine Sanctuaries via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Keeping Venice From Flooding | Earth Wise

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Since 2003, Venice Italy has been building a system of mobile gates at three inlets to its famous lagoon.  The project is called MOSE, the Italian word for Moses, but is actually an acronym for the Italian words meaning Experimental Electromechanical Module.  

The 78 mobile gates are metal box structures that sit at the bottom of inlet channels.  When a high tide is predicted, compressed air is pumped into the structures.  The air causes the barriers to rise up to the surface and block the flow of the tide, thereby preventing water from flowing into the lagoon.

The system had an important test on November 3 when water levels were predicted to rise four-and-a-half feet above normal at high tide and strong winds were blowing.  Water at that level is enough to flood 60% of the city, including the famous St. Mark’s Square, which is unfortunately the lowest part of the city.

Activating the flood gates proved to be successful.  Even though high tide water levels in fact rose 4.3 feet in the surrounding Adriatic Sea, they only reached 2.7 feet in Venice, which was enough to prevent significant flooding.

Rising sea levels have led to increasingly frequent floods in Venice.  In 2019, before the MOSE system was available for use, there were more than 25 high-water events swamping Venice, including one in November of that year that was the second worst on record.

Some researchers have calculated that the system will need to be closed for as much as 3 weeks a year by the end of the century even if emission reductions are reasonably effective.  If they aren’t, the gates may be closed for at least two months a year by 2080.

After many years of delays, setbacks and controversies, the system is finally operational.

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Venice Holds Back the Adriatic Sea

Photo, posted October 25, 2014, courtesy of Pedro Szekely via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Assisted Colonization | Earth Wise

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As the pace of climate change continues to quicken, many species seem to be unable to keep up and could face extinction as a result.   There is a potential strategy for people to help species reach places with more suitable physical and biological conditions.  People could carry endangered animals to habitats cut off by mountains, rivers, or human-made barriers.  They could plant endangered trees higher up mountain slopes or to locations further north.  Such actions have been termed assisted colonization.

People have been moving species around the world throughout human history for various reasons either intentionally or inadvertently.  But as a conservation strategy, assisted colonization is quite controversial.

The argument is whether the risk of moving species to more favorable conditions outweighs the risk of inaction.  The salvation of one species could mean the destruction of another.   A species that seems perfectly innocuous when moved to one place can become a rampant invader in another.

An upcoming international conference on Biological Diversity to be held this fall in China may take up the issue of creating a set of guidelines on assisted colonization.   Such guidelines would help people assess which species to focus on; where, when, and how to move them; how to weigh the risks of action and inaction; and how to conduct such actions across international borders.  Assisted colonization may be useful in some instances and not in others.  There needs to be a way for the world to decide whether it is warranted or not.  With climate change posing a growing threat to many of the world’s species, this is an issue that should be addressed.

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Amid Climate Pressures, a Call for a Plan to Move Endangered Species

Photo, posted July 16, 2014, courtesy of Mark Spangler via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Positive Tipping Points And Climate | Earth Wise

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A tipping point is a moment when a small change triggers a large and possibly irreversible response.

There has been much discussion of various tipping points that could accelerate climate change in catastrophic ways.  A recent paper from researchers at the University of Exeter in the UK discusses a couple of tipping points that could accelerate positive progress on mitigating climate change.

Electric vehicles account for only 2-3% of new car sales globally. In Norway, this figure is more than 50%, mostly thanks to policies that make electric cars the same price to buy as conventional cars.   According to the Exeter study, when EVs cost the same to manufacture as conventional cars, it will be a global tipping point.  China, the EU, and California together are responsible for half of the world’s car sales and each of these has targets to rapidly decarbonize their economies and policies in place to speed the transition to electric vehicles. 

Decarbonizing electric power is the other potential positive tipping point.  In Europe, carbon taxes on top of increasing renewable energy generation have tipped coal into unprofitability as they have led to the irreversible destruction of coal plants.  Globally, renewables are already generating electricity cheaper than fossil fuels in many countries.  Decarbonizing global power generation would in turn help accelerate decarbonization of large parts of transportation, heating and cooling, and industry.

These potential positive tipping points are by no means inevitable.  Appropriate policies are needed to overcome various barriers to the clean energy transition.  But major changes in transportation and electric power would have a tremendous impact on the global effort to combat climate change.

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Positive ‘tipping points’ offer hope for climate

Photo, posted July 14, 2020, courtesy of Jim Champion via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A New Fishway Technology | Earth Wise

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Freshwater fish populations have declined by more than 80% over the past forty years across the globe.  This is in part due to hundreds of thousands of dams, weirs, and barriers stopping their movements.  These river barriers have disrupted fish reproduction cycles the world over by preventing river fish from migrating to spawn.

Fishways or fish ladders are waterways constructed on or around obstructions in order to provide passageways for fish and other aquatic species.  Often, they consist of a series of small overflow weirs and pools constructed in the form of steps.  Fish need to jump from one pool to another to migrate to the upstream.  Such fish ladders require a large space to construct.  These and several other types of fishways tend to be expensive to install and maintain and are not always successful in allowing fish to get to where they need to go.

Researchers at the University of New South Wales in Australia have come up with an ingenious new type of fishway.  Called a “tube fishway”, it is a low-cost and low-energy installation that works by pumping fish at high velocity – protected by a cushion of bubbly water – through a tube running over the obstructing barrier to deliver them safely into the water on the other side.

They successfully demonstrated a prototype system on a rugged slope behind a campus building that transported fish from one tank to another about 25 feet up the slope.

Fish are attracted into the chamber by suitable geometry and the system uses the energy available from the upper reservoir to lift the fish.  Modeling shows that the system will work for pipes as large as three feet in diameter and could lift fish more than 300 feet vertically. 

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New fishway technology to get fish up and over those dam walls

Photo, posted October 19, 2019, courtesy of Andrew Harvey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Land Use Change And Flooding | Earth Wise

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Land use change refers to the conversion of a piece of land’s use by humans from one purpose to another. Land use change is commonly associated with biodiversity loss and increased greenhouse gas emissions.  But how does land use change impact water cycles? 

According to researchers from the University of Göttingen in Germany, IPB University, and BMKG (both in Indonesia), the expansion of monocultures, such as rubber and oil palm plantations, leads to more frequent and more severe flooding.  The researchers explain the increase in flooding “with a complex interplay of ecohydrological and social processes, including soil degradation in monocultures, the expansion of oil palm plantations into wetlands, and the construction of flood protection dams.” 

For the study, which was recently published in the journal Ecology & Society, the research team interviewed nearly 100 Indonesian farmers, villagers, and decision-makers in Sumatra.  The team supplemented its research with data on precipitation, river and groundwater levels, soil properties, and regional mapping. 

During large-scale land use change – like plantation expansions – newly-compacted soil causes rainwater to runoff as opposed to being absorbed.  As more plantations are established in floodplains, the owners try to control flooding on their land by building barriers.  But these dams often lead to increased flooding on neighboring lands.  This understandably triggers social tensions between other farmers and plantation owners.     

In order to reduce the negative impact of land use change on the water cycle, the research team suggests soil protection and improved planning – especially in floodplains – would be a good place to start.  

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Land use change leads to increased flooding in Indonesia

Photo, posted October 8, 2018, courtesy of Artem Beliaikin 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.

Foods of the Future? | Earth Wise

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In a world where many go hungry in the context of rapidly changing environments, many experts contend that alternative food sources will be necessary to solve global food security problems.  So-called novel food sources are central to this conversation, defined as foods with no history of consumption in a region – or perhaps anywhere.

Three popular examples are lab-grown meat, insect farming, and seaweed aquaculture.  Each of these offer opportunities as well as challenges.

Lab-grown meat can refer to actual animal tissues raised in vats as well as the increasingly common cultured plant products made to resemble meat.  Lab-grown meat faces push back from the livestock industry that contends it should not be labeled as any kind of meat. While results to date are positive, barriers still remain including concerns over product taste, healthiness, and cost.  And while less land- and water-intensive than conventional livestock, cultured meat production is still energy intensive.

Insects do form a significant part of diets across the globe but have yet to be embraced in any substantial way in western cultures.  Nutritionally, numerous species of insects are rich in key proteins, micronutrients, and minerals.  But the “yuck factor” is a big barrier to cross.

Seaweed is a long-established part of many East Asian diets and has many potential dietary uses.  Several selectively bred varieties of seaweed supply a range of valuable nutrients.  Growing seaweed does not tax freshwater and terrestrial resources.  But intensively cultivated seaweeds would have potential negative effects on local marine ecosystems.

There is no single solution to complex issues like food security.  Novel foods may very well form part of the solution to a growing food crisis.

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Insects, seaweed and lab-grown meat could be the foods of the future

Photo, posted March 12, 2009, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Should New York Build A Storm Surge Barrier?

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In 2012, Superstorm Sandy’s storm surge combined with a high tide and buried lower Manhattan under 13 feet of water.  Across all five boroughs, subways, highways, and parking garages flooded and homes and businesses were destroyed.  Sandy caused nearly $20 billion in damages in New York City alone and more than 50 people died.

Ever since that disaster took place, there have been discussions about building storm surge barriers to protect the city from future storms.  Columbia University’s Sabin Center recently hosted an event to discuss the feasibility of building such barriers.

A study by the U.S. Army Corps of Engineers called the NY and NJ Harbor and Tributaries Focus Area Feasibility Study (HATS, for short) evaluates five options for coastal protection, which range in scope and price.

The most extensive option would involve constructing six miles of storm surge gates along with 26 miles of floodwalls, levees, and buried seawalls.  This option would cost $62 billion but could theoretically save $131 billion in damages and protect 95% of the study area.

The study also considers the side effects of building storm surge barriers.  These include environmental impacts such as effects on fish and wildlife, water quality, noise and vibrations, and changes in water flow.  While these effects can be quite serious and there is opposition from many quarters related to environmental impacts, others point out that there is really no other credible defense against storm surge.  The debate over whether or not to build storm surge barriers could easily last for many more years.

In the bigger picture, storm surge barriers do nothing to protect against rain-driven flooding, sea level rise, and tidal floods which continue to increase.

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Should New York Build a Storm Surge Barrier?

Photo, posted October 30, 2012, courtesy of Pamela Andrade via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving Venice From The Sea

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The risks of rising sea waters are growing more apparent every year.  While the world struggles with taking action to reduce the carbon emissions that are driving the sea level rise, cities around the world are building sea walls designed to protect them from storm surges and flooding.   Most of these are massive, complex infrastructure projects that cost billions of dollars and take decades to complete.

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A Big Problem For The Giant Panda

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The giant panda, a national icon of China, has been the focus of an intensive, high-profile conservation campaign since the 1970s.  In an update to the IUCN’s Red List of Threatened Species last year, the giant panda had its designation changed from “endangered” to “vulnerable” following a nationwide census that revealed its population was improving.  But it appears as though this conservation success may be short-lived. 

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More Power From The Sea

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The Okinawa Institute of Science and Technology or OIST has been working on ways to generate electricity from the ocean for five years.  Their initial project, known as “Sea Horse” uses submerged turbines anchored to the sea floor that convert the kinetic energy of sustained natural currents into useful electricity, which is then delivered by cables to the land.  The project has been successful and OIST is now planning the next phase.

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Cheap Wind And Solar Power

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Multiple studies are now reporting that wind and solar power are the cheapest way to make electricity in a growing number of places around the world.   A thorough analysis of the levelized cost of energy – which considers every cost component from capital expenditures to operating and maintenance costs over a lifetime – shows that solar and wind power are winning the day.

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