Earth Wise

A look at our changing environment.

You are here: Home / Archives for environment

environment

Fuel From Lignin | Earth Wise

By Leave a Comment

Lignin is an organic polymer that provides the rigid structure of plants and is what gives wood and bark their characteristic properties.  Lignin typically comprises between 20 and 35% of the mass of wood.  The two major substances extracted from trees, grasses, and other biomass materials are cellulose and lignin.  Cellulose is used to make paper, bioethanol, and other products, but lignin is largely unused because it is difficult to break down into useful substances such as feedstocks for fuels.  As a result, lignin is largely wasted.  Worldwide, some 50 million tons of lignin are produced from paper and bioethanol manufacturing each year and almost all of that is simply burned to generate heat.

Lignin can be broken down using pyrolysis techniques at high temperatures to create bio-oils, but those oils lack sufficient hydrogen and contain too much oxygen to be useful as fuels.  There is a process called hydrodeoxygenation that adds hydrogen and removes oxygen, but it requires high temperatures and very high pressures as well as producing char and tar that reduces the efficiency of the process.

Researchers at Georgia Tech recently published work describing a new process for turning lignin into useful products.  They developed a dual catalyst system of super-acid and platinum particles that adds hydrogen and removes oxygen from lignin bio-oil and makes it useful as a fuel and source of chemical feedstocks. 

The new process could help meet the growing demand for bio-based oils as well as helping the forest product, paper, and bioethanol industries by providing an additional revenue stream from what previously was a waste product.

**********

Web Links

New Process Boosts Lignin Bio-oil as a Next-Generation Fuel

Photo, posted August 16, 2017, courtesy of evcabartakova via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Arctic Methane Starting To Release | Earth Wise

By Leave a Comment

An international team of researchers has found evidence that frozen methane deposits in the Arctic Ocean have started to be released over a large area of the continental slope off the East Siberian coast.  High levels of methane have been detected down to a depth of 1,100 feet in the Laptev Sea near Russia.

The slope sediments in the Arctic contain huge quantities of methane and other gases, known as hydrates.  Methane has a warming effect 80 times stronger than carbon dioxide over a 20-year period.  The US Geological Survey has identified Arctic hydrate destabilization as one of the four most serious scenarios for abrupt climate change.

The research team aboard a Russian ship said that most of the bubbles they observed coming up from the sea bottom were dissolving in the water, but that methane levels at the surface were four to eight times what would normally be expected.

Frozen methane deposits have been called the “sleeping giants of the carbon cycle.”  If these deposit releases were to reach a high enough level, it would be a tipping point that could greatly increase the speed of global warming.  With Arctic temperatures now rising more than twice as fast as the global average, the likelihood of a significant release of the frozen methane grows greater all the time.

Temperatures in Siberia were 9 degrees Fahrenheit higher than average from January to June this year.  Last winter’s sea ice melted unusually early.  This winter’s freeze has yet to begin, which is already a later start than any time on record.

These new discharges of methane are larger than anything found before and are a very worrisome occurrence.

**********

Web Links

Arctic methane deposits ‘starting to release’, scientists say

Photo, posted September 26, 2014, courtesy of the Office of Naval Research via Flickr. Photo credit: U.S. Navy photo by John F. Williams/Released.

Earth Wise is a production of WAMC Northeast Public Radio.

Food Waste Into Wearables | Earth Wise

By Leave a Comment

A new startup company spun out of the University of Toronto wants to make clothing from food waste.  If they are successful, you may someday buy a shirt or a pair of gym shorts made from banana peels, rotten tomatoes, coffee grounds, or moldy bread.

A problem faced by the clothing industry is that most textiles are blended with synthetic and non-renewable fiber polyester, which makes them unrecyclable.  An alternative that has come on the scene in recent years is polylactic acid (or PLA), which is a decomposable bioplastic that is currently used for food packaging, medical implants, and 3D printing.  It is likely that a sustainable future for the fashion industry will depend on the ability to make use of biodegradable and carbon-neutral materials.

PLA is typically made from cornstalk, but the startup – called ALT TEX – does not want to rely on a crop already used for feedstock, human consumption, and alternative fuel.  Furthermore, there is no need to plant more corn when there is an abundant supply of unused post-industrial food waste from growers, producers, and retailers that contains the same biological building blocks for producing PLA.

ALT TEX has been conducting experiments using discarded apples to create a PLA-based fabric that is strong, durable, decomposable, and cost effective.  They are working with farmers and food suppliers to access their waste. If their efforts are successful, it would be possible to divert significant amounts of organic waste that currently emits the powerful greenhouse gas methane and instead enable the fashion industry to be more sustainable.

**********

Web Links

Earth-friendly fashion: U of T startup turns food waste into wearables

Photo, posted August 30, 2019, courtesy of Ruth Hartnup via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Quiet In The Pandemic | Earth Wise

By Leave a Comment

The early months of the Covid-19 pandemic had dramatic effects on many aspects of our daily lives.  Vehicle traffic, air pollution, and many other aspects of modern life saw reduced levels not seen in decades.  It turns out that one of the things that saw reduced levels was people’s exposure to environmental noise.

According to University of Michigan researchers, daily average sound levels dropped in half during the time that local governments made announcements about social distancing and issued stay-at-home orders in March and April as compared to noise levels measured in January and February.

The data was acquired from the Apple Hearing Study, which looked at noise exposure data from volunteer Apple Watch users in Florida, New York, California, and Texas.  The analysis included more than half a million daily noise levels measured before and during the pandemic shutdown.

The noise reduction – 3 decibels, which is a factor of two in noise level – is considered to be quite large and could have a significant effect on people’s overall health outcomes over time.

The four states studied had differing responses in terms of stay-at-home orders.  Both California and New York both had really drastic reductions in sound that happened very quickly, whereas Florida and Texas had somewhat less of a reduction.

The study demonstrated the utility of everyday use of digital devices in evaluating daily behaviors and exposures.  This sort of analysis could allow researchers to begin describing what personal sound exposures are like for Americans who live in a certain state, or are of a certain age, or who do or don’t have hearing loss.  The Apple Hearing Study is continuing and is still accepting new participants.

**********

Web Links

Stay-at-home orders cut noise exposure nearly in half

Photo, posted April 10, 2020, courtesy of Joey Zanotti via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Even The Deep Sea Is Warming | Earth Wise

By Leave a Comment

Approximately 75% of the area covered by ocean is deep, dark, and cold.  This is known as the deep sea.  But even in these remote regions of the planet things are heating up. 

According to a new study published in the journal Geophysical Research Letters, researchers analyzed a decade of hourly temperature readings at four depths in the Atlantic Ocean’s Argentine Basin, off the coast of Uruguay.  The research team selected recording depths that would best represent the average depth of the ocean, which is just over 12,000 feet. 

The researchers found that deep sea temperatures fluctuate more than was previously known.  They also detected a warming trend at the bottom of the ocean.  In fact, all recordings indicated a warming trend of 0.02 to 0.04 degrees Celsius per decade between 2009 and 2019.  This is a significant warming trend in the deep sea because temperature fluctuations are typically measured in thousandths of a degree. 

Researchers say this increase is consistent with warming trends in the shallow ocean associated with anthropogenic climate change.  However, they say more research is needed to better understand what is driving the warming temperatures in the deep sea. 

A better understanding of what is driving these changes could have far-reaching implications.  Since oceans absorb a significant amount of the world’s heat, learning about the oceans’ temperature trends could help researchers better understand temperature fluctuations in the atmosphere as well.

The researchers hope their findings will demonstrate the need to survey deep ocean temperatures annually in order to better identify the long-term trends. 

**********

Web Links

The deep sea is slowly warming

Photo, posted July 1, 2018, courtesy of NOAA Ocean Exploration and Research via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Community Solar With Storage In New York | Earth Wise

By Leave a Comment

Community solar allows members of a community to share the benefits of solar power even if they cannot or prefer not to install solar panels on their own property.  There are several models for how community solar works, but all of them allow members to benefit from solar power being generated by an offsite solar array by effectively allocating a portion of its output to them.  In any event, community solar can save money on electric bills and allow people to make use of renewable energy for their needs.

A next step in the evolution of a decentralized energy system is incorporating energy storage into community solar projects.  The first one of these in New York State has now been completed in Yorktown Heights in Westchester County.  The project consists of 557kW of rooftop solar in the form of nearly 1,500 solar panels paired with 490kW of four-hour Tesla Powerpack battery energy storage.  The system is expected to provide 150 participants with approximately 10% savings on their monthly electric bills over 25 years, as well as providing power to 12 Tesla electric vehicle charging stations.

The project was funded by NYSERDA, under its Retail Energy Storage Incentive program, which currently includes 50 community solar-storage paired projects across New York State that are expected to be installed in the next two to three years.

New York has been actively promoting community projects in support of goals announced by Governor Andrew Cuomo to install 6,000MW of solar in the state by 2025 and 3,000MW of energy storage by 2030.

**********

Web Links

First community solar-storage project completed in New York

Photo, posted June 21, 2017, courtesy of Franck Michel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A New Super-Enzyme For Breaking Down Plastic | Earth Wise

By Leave a Comment

The problems caused by plastic waste continue to grow.  Plastic pollution is everywhere, from the Arctic to the depths of the ocean.  We consume microplastics in our food and breathe them in the air.  It is very difficult to break down plastic bottles into their chemical constituents in order to make new ones from old ones. Therefore, we continue to produce billions of single-use plastic bottles, creating more and more new plastic from oil each year. 

Scientists at the University of Portsmouth in the UK have developed a new super-enzyme that degrades plastic bottles six times faster than before.  They believe that the new enzyme could be used for plastic recycling within a year or two.

The super-enzyme was derived from bacteria that naturally have the ability to eat plastic.  The researchers engineered it by linking two separate enzymes, both of which were found in a plastic-eating bug discovered in a Japanese waste site in 2016.  They revealed an engineered version of the first enzyme in 2018, which started breaking down plastic in a few days.  They had the idea that connecting two enzymes together would speed up the breakdown of plastic.  Such linkage could not happen naturally in a bacterium. 

Carbios, a French company, announced a different enzyme in April that can degrade plastic bottles within 10 hours but requires heating above 160 degrees Fahrenheit.  The new super-enzyme works at room temperature.

The team is now examining how the enzymes can be tweaked to make them work even faster.  Meanwhile, they plan to work in partnership with companies like Carbios, to bring super-enzymes for breaking down plastics into commercial use.

**********

Web Links

New Super-Enzyme Can Break Down Plastic at Rapid Pace

Photo, posted March 24, 2017, courtesy of the USFWS – Pacific Region via Flickr. Photo credit: Holly Richards/USFWS.

Earth Wise is a production of WAMC Northeast Public Radio.

The Largest Turbines In The Largest Offshore Wind Farm | Earth Wise

By Leave a Comment

The world’s largest planned offshore wind farm is going to make use of the world’s largest installed offshore wind turbines.  The Dogger Bank Wind Farm in the North Sea off the Yorkshire coast of England will ultimately generate electricity for more than 4.5 million homes in the United Kingdom.

The 3.6 GW project will cost $10 billion and will be developed in three phases, the first two of which will use 13-MW wind turbines built by General Electric.  The turbine’s blades measure 351 feet – longer than a soccer field.  The turbines stand more than 850 feet tall, which is five times the size of the Arc de Triomphe.  GE claims that a single rotation of one of these huge turbines can supply enough electricity to power the average British household for two days.  When the project is completed in 2026, it will generate 5% of the United Kingdom’s electricity.

The previous version of GE’s Haliade-X turbines, rated at 12 MW, were ordered by the energy company Orsted for installation in two forthcoming U.S. windfarm: the Skipjack Farm off the coast of Maryland, and the Ocean Wind farm off the coast of New Jersey.  The new version will be the largest turbines to reach operation in a commercial project.  Meanwhile, Siemens Gamesa has a 14 MW turbine under development.

The order for 190 of the 13 MW giant turbines for the Dogger Bank farm arrived at GE on the same day that the company announced that it will no longer supply power equipment to new coal plants.  Work on the Dogger Bank project started in January in an area of the North Sea that was previously dominated by oil and gas development.

**********

Web Links

World’s Biggest Offshore Wind Farm Will Boast World’s Largest Installed Turbines

Photo, posted February 22, 2014, courtesy of Jonny Longrigg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Nitrous Oxide Is No Laughing Matter | Earth Wise

By Leave a Comment

Carbon dioxide is the most well-known of greenhouse gases.  But there are others deserving of their own spotlight.  Nitrous oxide is one of them.  It turns out that the same “laughing gas” once used by dentists as an anesthetic is pretty bad for the environment.  In fact, it’s more than 300 times more potent as a greenhouse gas than carbon dioxide, and it can remain in the atmosphere for more than 100 years.

According to a new study by a team of international scientists, rising nitrous oxide emissions around the world are jeopardizing the climate goals of the Paris Agreement.  The growing use of nitrogen fertilizers in global food production is increasing atmospheric concentrations of nitrous oxide.

The study, which was led by Auburn University and recently published in the journal Nature, finds that nitrous oxide emissions are increasing faster than any emission scenario developed by the Intergovernmental Panel on Climate Change.  The current trajectory would lead to global mean temperature increases well above 3°C from pre-industrial levels.  The Paris Agreement aims to limit global warming to less than 2°C.    

According to the study, nitrous oxide levels have risen 20% from pre-industrial levels, with the fastest growth observed in the last 50 years due to emissions from human activities.  The largest contributors to nitrous oxide emissions come from East Asia, South Asia, South America, and Africa.  The United States, China, and India dominate nitrous oxide emissions from synthetic fertilizers, while Africa and South America dominate releases of nitrous oxide from natural sources, like livestock manure. 

Nitrous oxide emissions pose an increasing threat to the climate.  

**********

Web Links

Nitrous oxide emissions pose an increasing climate threat, study finds

Photo, posted April 22, 2012, courtesy of Bill Meier via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Do Forests Grow Better With Our Help? | Earth Wise

By Leave a Comment

Tree planting has become a worldwide cause.  International calls to plant a trillion trees to combat climate change have led to multiple initiatives by countries around the world.  Even the current U.S. administration, with support from businesses and nonprofits has promised to plant over 800 million trees across an estimated 2.8 million acres.  Planting trees is widely seen to be a vital nature-based solution to climate change; a way of moderating its effects as the world works to reduce carbon emissions.  However, recent studies have created some pushback from that view.

The new studies are not opposed to trees.  What they have revealed is that allowing forests to grow back naturally is a better strategy than planting trees.  The new data has shown that, among other things, estimates of the rate of carbon accumulation by natural forest regrowth have on average been 32% too low and, for tropical forests, have been 53% too low.

A new study published in Nature identified 1.67 billion acres that could be set aside to allow trees to regrow.  It excludes land under cultivation or built on, along with various existing valuable ecosystems. 

Natural regrowth allows nature to select which tree species take hold and turns out to happen quite rapidly and in a widespread manner.  The great thing about natural restoration of forests is that it often requires nothing more than human inaction.  Because it requires no policy initiatives, investments, or oversight, data on its extent is rather scarce.  But the data we have reveals that wherever forests have been allowed to recover on their own, it appears to happen rapidly and with great success.

**********

Web Links

Natural Debate: Do Forests Grow Better With Our Help or Without?

Photo, posted September 5, 2015, courtesy of Nicholas A. Tonelli via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Essential Oils And Organic Crops | Earth Wise

By Leave a Comment

Essential oils are concentrated liquids extracted from plants.  They are called “essential” in the sense that they contain the essence of the fragrance that is characteristic of the plant.  Essential does not mean indispensable or usable by the human body.  But despite that fact, essential oils have been used in folk medicine throughout history. 

In recent times, essential oils have frequently been used in aromatherapy.  Generally speaking, medicinal uses of essential oils are controversial, and, in some cases, they have even been demonstrated to be dangerous.

Research has shown that essential oils have potential as natural pesticides.  Recently, the USDA has funded research into the use of essential oils to battle pests and diseases of organic crops.

U.S. organic food sales topped $50 billion in 2018 and fruits, vegetables, and other specialty crops combined make up more than a third of organic sales.  In order to meet consumer demand, farmers need ways to battle pests and diseases that often accompany organic crop growth.

A four-year project at the University of Hawaii at Manoa is entitled “Plant Safety, Horticultural Benefits, and Disease Efficacy of Essential Oils for Use in Organically Grown Fruit Crops:  From the Farm to the Consumer.”   The researchers will work with certified organic producers in Hawaii, Florida, South Carolina, Georgia, and California to evaluate the effectiveness of plant essential oils on major fruit pathogens such as avocado scab, anthracnose fungal disease, and powdery mildew on targeted tropical and temperate fruit crops such as avocado, mango, blueberry, and peach.

The goal is increase orchard productivity of the expanding organic fruit industry.

**********

Web Links

Essential oils could keep pests, disease from organic crops

Photo, posted January 6, 2015, courtesy of Abi Porter via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Hottest September | Earth Wise

By Leave a Comment

Here’s a news item that is like many other recent news items:  September 2020 was the hottest September since 1880, according to the National Oceanic and Atmospheric Administration.   The warm September is a part of a year that so far is poised to be at least the second hottest year in the 141-year climate record.

The ten warmest Septembers on record have all occurred since 2005, and the seven warmest Septembers have occurred in the past seven years.

So far, the year-to-date average global temperature has been the second warmest on record, being just 0.07 degrees Fahrenheit lower than the record year-to-date temperature set in 2016.  Expectations are that 2020 will end up somewhere among the three warmest years on record for the globe.

September was warm in many places around the world.  California and Oregon had their warmest September ever.  Europe had its warmest September on record, Asia had its second warmest September on record as did Australia and South America. 

So far, it has been the hottest year-to-date on record in Europe, Asia, and the Gulf of Mexico.  No land or ocean areas anywhere had record-cold year-to-date temperatures. 

Global temperatures represent an average over the entire surface of the planet.  The fact that the global temperature is now nearly one Celsius degree above the 20th century average means that a vast amount of heat has been added in order to warm all the oceans, atmosphere, and land by that much.  So, every uptick in global temperature is a big deal.

Meanwhile, the average Arctic sea ice coverage for September was the second smallest on record.  The 14 smallest minimum annual sea ice extents have all occurred in the past 14 years.

**********

Web Links

Earth just had its hottest September on record

Photo, posted September 2, 2020, courtesy of Tim Vrtiska via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fall Safety Tips | Earth Wise

By Leave a Comment

The fall season has its own weather-related hazards, such as raging wildfires across the West and a busy hurricane season in the Atlantic.  There might even be snow in some places.  The National Weather Service issued a set of four broad safety tips for being prepared for the dangers of fall weather.

With regard to wildfires, it is important for smokers to properly discard cigarettes, for people to avoid activities with open flames or sparks, and to use fire-resistant landscaping around our homes. The Weather Service issues Red Flag Warnings when conditions are ripe for wildfires.

In this busy hurricane season, even people who don’t live in hurricane surge evacuation areas need to know their home’s vulnerability to damage from high winds and inland flooding.  People should have a plan that includes an emergency kit and a safe place to shelter should they need to evacuate.

It is important to have a plan in case strong winds pose a threat.  When preparing for an extreme wind event, secure objects that can be tossed or rolled, trim trees near homes, and have a plan in case of an extended power failure.  Strong winds can even happen on a clear day.

The key advice in case you encounter flood waters is “turn around, don’t drown.”  It is never safe to walk or drive into a flooded roadway.  It is best to delay travel until roads are clear.

Fall can be the most beautiful season of the year, but it also has its dangers.  Following advice such as that provided by the Weather Service is prudent and potentially life-saving.

**********

Web Links

Four safety tips for fall hazards: Small actions can have big impacts

Photo, posted October 30, 2014, courtesy of Virginia State Parks via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Alien Species On The Rise | Earth Wise

By Leave a Comment

Alien species are species that are introduced, accidentally or intentionally, outside of their natural geographic range as a result of human activities.  More than 35,000 alien species have been recorded through 2005, which is the most recent year for which researchers have comprehensive global data. 

Some of the alien species go on to become invasive alien species, which can have damaging impacts on both ecosystems and economies.  In fact, alien species are one of the main drivers of plant and animal extinctions around the globe.  

According to a new study by an international research team involving University College London, the number of alien species, particularly insects, arthropods and birds, is expected to increase globally by 36% by 2050 when compared to 2005 levels.  The research was recently published in the journal Global Change Biology.

Using a mathematical model developed for the study, the researchers identified high levels of variations between regions.  For example, the largest increase in alien species by the middle of the century is expected in Europe, where numbers are predicted to jump by 64%.  The temperate regions of Asia, North America, and South America are also predicted to be hotspots of alien species.  The lowest relative increase in alien species is expected in Australia.

The researchers do not expect a reversal or slowdown in the spread of alien species.  In fact, with global transportation and trade forecasted to increase in the coming decades, they anticipate many new species will infiltrate non-native habitats by hitching rides as stowaways.   

According to the research team, it would take a concerted global effort with stricter regulations and more rigorous enforcement to slow the flow of new species. 

**********

Web Links

Alien species to increase by 36% worldwide by 2050

Photo, posted October 3, 2016, courtesy of the Asian Carp Regional Coordinating Committee via Flickr. Photo credit: Ryan Hagerty/USFWS.

Earth Wise is a production of WAMC Northeast Public Radio.

Paying To Combat Climate Change | Earth Wise

By Leave a Comment

The majority of Americans believe that climate change is happening, that human activities are largely responsible, and are actually willing to put up their own money to help fight it.   Unfortunately, these views diverge sharply along party lines and, as in many other areas these days, the will of the overall majority has little influence on policy.

According to Yale University research, 73% of adults think that global warming in happening and 57% think it is mostly caused by human activities.  Furthermore, only 32% believe it is due to natural forces.

A survey conducted in the U.S. in August found that more than two-thirds of Americans – actually 70% – indicated willingness to donate a percentage of their personal income to support the fight against climate change.

Breaking that down further, 28% were willing to provide less than 1% of their income, 33% were willing to contribute 1-5% of their income, 6% said they would give 6-10% of their income, and 3% said they would contribute more than 10% of their income.  On the other hand, roughly 30% indicated that they were unwilling to contribute.

The survey also looked at opinions on how the fight against climate change should be paid for.  The majority (59%) chose government incentives for both businesses and consumers.   Three other options each favored by over 40% of those surveyed were taxes, conservation programs, and business investments. 

Another finding of the survey was that 44% are dissatisfied with the job that the federal and state governments are doing to address climate change, 35% are somewhat satisfied, and only 21% are very or completely satisfied with the government’s role.

**********

Web Links

Yale Climate Opinion Maps 2020

Two-thirds of Americans are willing to donate part of their income to fight climate change

Photo, posted April 29, 2017, courtesy of majunznk via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Hydropower And Floating Solar | Earth Wise

By Leave a Comment

According to a new analysis by the National Renewable Energy Laboratory, hybrid systems of floating solar panels and hydroelectric plants have the potential to produce a significant portion of the world’s electricity.

According to their estimates, adding floating solar panels to bodies of water that host hydropower stations could produce up to 7.6 terawatts of power a year from the solar systems, resulting in about 10,600 terawatt-hours of energy.  The total global electricity consumption in 2018 was 22,300 terawatt-hours.  So, the potential in terms of the global appetite for electricity is very large.

This estimate is certainly optimistic.  It does not take into account economic feasibility or specific market demand.  What it does represent is an estimate of the technical and performance potential of floating photovoltaics at hydroelectric facilities.

Floating solar is just starting to be used in the U.S., but it has already caught on overseas where space for ground-mounted systems is at a greater premium. 

According to the NREL study, nearly 400,000 freshwater hydropower reservoirs across the globe could host floating PV sites that could be used in conjunction with the existing hydroelectric plants.  One important advantage of this approach is that the hybrid system would reduce transmission costs by linking to a common substation.  In addition, the two technologies could balance each other, with solar power taking up the slack in dry seasons and hydropower working well in rainy seasons.  In some places, pumped storage hydropower could be used to store excess solar generation.

There is great potential in hybrid floating solar/hydroelectric power.

**********

Web Links

Untapped potential exists for blending hydropower, floating solar panels

Photo, posted April 12, 2009, courtesy of Alexis Nyal via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Artificial Reefs As Havens For Marine Predators | Earth Wise

By Leave a Comment

Climate change, pollution, development and other stresses have accelerated the decline of reef ecosystems across much of the world’s oceans in recent years.  Large predators such as sharks, mackerels, barracudas, jacks and others that formerly fed around reefs have had to venture outside their normal migratory routes in search of suitable alternatives.

According to a new study by Duke University, marine predators have taken up residence at shipwrecks and other artificial reefs.  The study surveyed 30 sites along the North Carolina coast and found that predator densities were up to five times larger at the 14 artificial reefs surveyed than at the 16 natural reefs in the survey.

Shipwrecks, particularly those that rose between 4 and 10 meters up into the water column, were a big favorite of the fishes.  Some of those sites supported predator densities up to 11 times larger than natural reefs or low-profile artificial reefs.  The shipwrecks are basically high-rise timeshares in the sea.

The findings of the survey show that artificial reefs can support large predators, supplementing natural reefs if the design and placement of the artificial reefs are appropriate.  In addition, when it comes to designing artificial reefs, there appears to be a height advantage.  So, reefs either made from sunken ships or at least made to resemble them would be desirable.

Because undersea predators help maintain healthy and sustainable populations of species lower in the food web, providing suitable habitat for the predators is extremely important.  Based on the study, it appears that the strategic use of artificial reefs can be an effective way to help counter the increasing loss of natural habitat on the ocean bottom.

**********

Web Links

Artificial Reefs Take on a Towering Presence as Havens for Marine Predators

Photo, posted July 29, 2014, courtesy of NOAA Photo Library via Flickr. Photo credit: Flower Garden Banks National Marine Sanctuary

Earth Wise is a production of WAMC Northeast Public Radio.

Using CO2 To Convert Seawater Into Drinking Water | Earth Wise

By Leave a Comment

A chemist at the University of Copenhagen has invented a technology that uses carbon dioxide to convert seawater into drinking water within minutes.  This desalination technology has the potential to replace electricity with CO2 and be used in survival gear and in large-scale industrial plants in places where people don’t have clean drinking water.

Over 800 million people worldwide lack access to clean drinking water and that number is growing rapidly.  Seawater is a vital source of drinking water in many parts of the world, but desalination faces the major challenge of being highly energy intensive.  Desalination plants use huge amounts of fossil fuel-generated electricity and therefore contribute to climate change.

The Copenhagen technology is reminiscent of a SodaStream machine.  Carbon dioxide is added to water, initiating a chemical reaction.  But instead of using it for bubbly carbonation, it is used to separate salt from water.  It works by adding a chemical called CO2-responsive diamine to saltwater.  The diamine compound binds with the added CO2 and acts as a sponge to absorb the salt, which can then be separated.  The entire process takes one to ten minutes.  Once the CO2 is removed, the salt is released again, allowing the diamine to be reused for several more rounds of desalination.

In the laboratory, the method removed 99.6% of the salt in seawater.  The technology is still being developed to lower its price and optimize the recycling process.  It is also being tested on a small scale in the form of water bottles fitted with special filters that can be used in lifeboats or in other outdoor settings.  Ultimately, it could be used to greatly reduce the energy consumption of desalination plants.

**********

Web Links

Chemist uses CO2 to convert seawater into drinking water

Photo, posted January 10, 2015, courtesy of Daniel Orth via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Marine Life Moving The Wrong Way | Earth Wise

By Leave a Comment

As the oceans have warmed in recent decades, various marine species ranging from whales to corals have begun to shift poleward in search of cooler waters.  But a new study, reported in the journal Nature Climate Change, found that many sedentary marine species – including snails, worms, and mussels – are actually being transported in the wrong direction.

What is happening is that bottom-dwelling species – also known as benthic species – in the northwest Atlantic Ocean are spawning earlier in the year because of the warmer water temperatures.  But earlier in the year is when ocean currents travel southward.  As a result, the larvae of these animals are being carried into warmer waters rather than cooler ones, threatening their survival and shrinking their ranges.  These larvae grow into adults in these warmer regions and are basically trapped there.  This creates a feedback loop where the situation for the species gets worse and worse.  Species like common sand dollars and the economically important blue mussel have had a 30 to 50% contraction of their ranges.

The result is that a number of bottom-dwelling species that previously were quite abundant have entirely disappeared from the outer shelf.

The researchers at Rutgers University likened this “wrong-way migration” of bottom-dwelling marine life to so-called elevator-to-extinction events that have been taking place in mountainous regions.  This is where species such as birds and butterflies move to higher and higher elevations to escape rising temperatures until there is nowhere else for them to go.

The essential fact that this research reveals is that species don’t necessarily move to places where the climate is congenial for them.  They may unfortunately end up migrating to even worse conditions.

**********

Web Links

As Oceans Warm, Some Species Are Moving in the Wrong Direction

Photo, posted June 10, 2016, courtesy of James_Seattle via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saharan Dust And The Amazon | Earth Wise

By Leave a Comment

We talk about globalization primarily in the context of how human activities connect up distant parts of the world.  But there are natural processes that are global in scope as well.  One of these is the transportation of mineral-rich dust from the Sahara Desert in North Africa to the Amazon Basin in South America.

Every year, this dust is lifted into the atmosphere by winds and carried on a 5,000-mile journey across the North Atlantic.  It turns out that this dust plays a critical role in the Amazon basin ecosystem.  The Amazon Basin in turn plays a major role in global climate.  Its trees and plants remove huge quantities of carbon dioxide from the atmosphere and stores the carbon in vegetation.

The transcontinental journey of dust is important because of what is in the dust.  The dust picked up from ancient lake beds in Chad comes from rock minerals formed by dead microorganisms and is loaded with phosphorus.  Phosphorus is an essential nutrient for plant growth and is in short supply in Amazonian soils.  Local nutrients like phosphorus in the Amazon mostly come from fallen, decomposing leaves and organic matter but tend to be washed away by rainfall into streams and rivers. 

Studies have shown that the phosphorus that reaches Amazon soils from Saharan dust is essential to replace the amounts lost to rain and flooding.

Recent research has found that the quantities of dust transported to South America are inversely linked to rainfall in North Africa and is likely to be affected by climate change.  Changes in dust transport could affect plant growth in the Amazon and the amount of CO2 removed from the atmosphere.  The forces that affect the climate are truly global in nature.

**********

Web Links

Study quantifies Saharan dust reaching Amazon

Photo, posted April 19, 2011, courtesy of CIAT via Flickr. Photo credit: ©2011CIAT/NeilPalmer.

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...)