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Keeping Lights On For Turtles

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Gillnets are one of the most common types of fishing gear and are used extensively in most places where people fish for food.  They operate by suspending a wall of netting in the water column.

Unfortunately, they are not selective in the species they catch.  Sea turtles are one of the most common bycatch species that become entangled in these nets.  When turtles are caught in gillnets, they can drown and die.  Marine mammals, seabirds, and sharks are also frequently caught in gillnets.

Recently, researchers have been experimenting with illuminating the nets with LED lights to see if increasing net visibility reduces sea turtle bycatch.

Studies in Mexico show green sea turtle bycatch is reduced between 40-60% with no changes in target catch.  Studies in Peru show green sea turtle bycatch is reduced between 65-80% with no changes in target catch.  Studies in Indonesia show green olive ridley, and hawksbill sea turtle bycatch is reduced by 60% with increases in target catch and catch value.

Recent research shows that net illumination also reduces bycatch of other protected species such as seabirds, sharks and rays, as well as dolphins and porpoises.

The use of illuminated gillnets could prove beneficial to both sea turtles and fisherman by reducing the bycatch that can damage fishing gear. 

Studies are now underway off the coast of North Carolina, where state gillnet fisheries are carefully managed to reduce turtle bycatch.  Initial studies show that net illumination does not change target catch rates and may even decrease the bycatch of unwanted fish species.  When it comes to protecting sea turtles, it looks like a good idea to keep the lights on.

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Illuminated Nets Could Provide A Brighter Future For Sea Turtles

Photo, posted June 2, 2016, courtesy of NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Microplastic Diet

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According to a new study published in the journal Environmental Science & Technology, Americans consume more than 70,000 microplastic particles every year from the food they eat, the water they drink, and the air they breathe.

While the health impacts of ingesting these tiny particles are largely unknown, there is the potential for the plastic to enter human tissues and cause an immune response or perhaps release toxic chemicals into the body.

The analysis by biologists at the University of Victoria in Canada examined data from 26 previous studies on microplastic contamination.  It found that Americans eat and drink an estimated 39,000 to 52,000 microplastic particles each year, depending on their age and sex.  The numbers jump to 74,000 to 121,000 when inhalation of microplastics is included.

Americans who drink water solely from plastic bottles consume an additional 90,000 particles annually, compared to only 4,000 particles for people who only drink tap water.

The researchers warn that their findings are likely to be drastic underestimates of the problem.  Several major U.S. food groups – including poultry, beef, dairy, grains, and vegetables – have not been studied for their microplastic contamination.  Thus, the estimate of microparticle ingestion is associated with only 15% of an average person’s caloric intake.  Furthermore, there is no assessment currently available for how much plastic might be entering our bodies from food packaging.

The report’s findings suggest that microplastics will continue to be found in the majority if not all items intended for human consumption.  Realistically, the only way to reduce the human consumption of microplastics will be to reduce the production and use of plastics.

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Americans Consume Tens of Thousands of Microplastic Particles Every Year

Photo, posted June 18, 2016, courtesy of Sirirat Kornsongkaew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Desalination On The Rise

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Desalination has been regarded for decades as a solution for providing fresh water to places where it is scarce.  With drought becoming more common around the world – sometimes even in places where water supplies were thought to be ample – there is increasing pressure to bring new desalination plants online.

San Diego gets only 12 inches of rain a year and has no groundwater.  It gets half its water from the distant Colorado River, and that source is becoming increasingly unreliable.  Thus, it is no surprise that America’s largest desalination plant is in Carlsbad, about 30 miles north of San Diego.  That plant provides about 10% of the fresh water needs of the region’s 3.1 million people.

There are 11 desalination plants in California, and 10 more are proposed. Desalination is huge in Saudi Arabia, Australia and Israel.  Globally, more than 300 million people get their water from desalination.

But there are problems.  Desalination is expensive and energy-intensive.  If the process is powered by fossil fuels, it contributes to global warming.  There are ecological impacts as well since it takes two gallons of sea water to make a gallon of fresh water, and the gallon left behind is extremely briny and potentially harmful to dump back into the sea.  The intake systems of desalination plants are also harmful to fish and other aquatic creatures.

The cost of desalination has dropped by more than half over the last 30 years but water from it still costs about twice as much as that from other main sources.  The technology is getting better and cheaper, but the industry must confront and solve serious environmental and economic problems in order for desalination to be able to meet the needs of an increasingly thirsty world.

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As Water Scarcity Increases, Desalination Plants Are on the Rise

Photo, posted January 12, 2011, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fresh Water Under The Sea

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A new survey of the sub-seafloor off the U.S. Northeast coast has revealed the existence of a gigantic aquifer of relatively fresh water trapped in porous sediments lying beneath the salty ocean.  This appears to be the largest such formation ever found.

The newly-discovered aquifer stretches from the shore at least from Massachusetts to New Jersey and extends more-or-less continuously out about 50 miles to the edge of the continental shelf.   The deposits begin at around 600 feet below the ocean floor and bottom out at about 1,200 feet.  If all that water was found on the surface, it could create a lake some 15,000 miles in area.  The researchers estimate that the region holds at least 670 cubic miles of fresh water.

Researchers made use of innovative measurements of electromagnetic waves to map the water, which had not been detected by other technologies.   It was already known that fresh water existed in places under the sea bottom as a result of oil drilling as far back as the 1970s.  But there was previously no hint of the extent of the undersea aquifer. 

The water probably was trapped by sediments deposited during the last ice age when sea levels were much lower.  But modern subterranean runoff from land sources might also be a contributor.

If water from the aquifer was to be withdrawn, it would still have to be desalinated for most uses, but the cost would be much less than processing ordinary seawater.  There is probably no need to do this in the Northeastern US, but the discovery suggests that such aquifers probably lie off many other coasts worldwide and could provide desperately needed water in places like southern California, Australia, the Mideast or Saharan Africa.

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Scientists Map Huge Undersea Fresh-Water Aquifer Off U.S. Northeast

Photo, courtesy of August 1, 2015, courtesy of Michael Vadon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Degraded Permafrost In The Arctic

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Permafrost is defined as rock or soil that has been at or below the freezing point of water for two or more years.  Most of it is located in high latitudes in and around the Arctic and Antarctic regions.   Permafrost covers nearly a quarter of the exposed land in the Northern Hemisphere.

Permafrost can contain many different materials including bedrock, sediment, organic matter, water and ice.  Because of the presence of organic matter, permafrost is potentially the source of significant methane emissions if it thaws and the trapped biomass begins to rot.

A recent study looked at the results of 30 years of aerial surveys and extensive ground mapping of an area of Canada’s high Arctic polar desert known as the Eureka Sound Lowlands.  This area has an extremely cold climate and the permafrost there is over 1/3 of a mile thick.  It has long been assumed that this landscape was stable.

Research led by McGill University in Montreal has found that this is not the case.  The increases in summer air temperatures seen in recent years are initiating widespread changes in the landscape.

A particular landform known as a retrogressive thaw slump that forms when ice within permafrost melts and the land slips down is widely occurring in the area.  The absence of vegetation and layers of organic soil in these polar deserts make permafrost in the area particularly vulnerable to increases in summer air temperatures.

The research indicates that despite the cold polar desert conditions that characterize much of the high Arctic, the interaction between ice-rich permafrost systems and climate factors is complex and the links between global warming and permafrost degradation are not well understood.

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Widespread permafrost degradation seen in high Arctic terrain

Photo, posted August 11, 2018, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Powering Cars With Cactus Juice

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Back in 2016, a company called Nopalimex, located in Micoacan, central Mexico, built the world’s first cactus-powered energy plant.  The facility utilizes a biodigester to make biogas from nopal, also known as prickly pear cactus.  The nopal plant has been called the ‘Green Gold of Mexico’ and is a staple in Mexican diets, medicine and cosmetics.

Nopalimex is now using the cactus to make biofuel for vehicles.

The fruit of the cactus is pureed, mixed with manure, and then left to decompose, producing methane.  The methane produced – about eight tons a day – fuels the biodigester which powers the company’s corn chip and cactus chip production and is being tested in a fleet of government vehicles.

The biogas will cost just 65 cents per liter, which is about a third cheaper than the cost of regular gasoline.  Using prickly pear as a feedstock for biofuel is attractive because it can be grown in places where traditional energy crops cannot.  One can imagine vast fields of cacti in remote, arid areas of the country where normal crops cannot grow.  It would not suck up the resources or space needed to feed people, which is an ongoing criticism of current bioenergy crops.

As long as the nopals are regularly replanted, the process is almost entirely sustainable, producing only water and nopal waste, which can be used to fertilize other crops.

Finding sustainable ways to produce fuel while doing minimal damage to the environment is an important challenge for countries around the world.  In Mexico, harnessing the power of the prickly pear cactus is a unique and clever solution.

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Mexico’s ‘green gold’: The company powering cars with cactus juice

Photo, posted July 8, 2006, courtesy of Christian Frausto Bernal via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Energy Vault

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A potentially transformative utility-scale energy storage technology has won a 2019 “World Changing Idea” award from Fast Company magazine.  Known as the Energy Vault, the technology seeks to be the successor to the granddaddy of grid energy storage:  pumped hydro.

Shifting water between higher and lower reservoirs is still basis of the vast majority of global grid storage capacity.  But it is limited both by its unique location needs and by environmental regulations.

A start-up company also called Energy Vault and based in both Switzerland and Southern California has come up with an extremely creative grid storage concept.  The technology consists of a six-armed crane that stacks huge concrete blocks using a currently available source of cheap and abundant grid electricity, and then drops them down to generate electricity when needed.

The system is said to operate at about 90% efficiency and can deliver long-duration storage at half the prevailing price on the market today.

A full-scale Energy Vault plant, called an Evie, would look like a 35-story crane with six arms, surrounded by thousands of manmade concrete blocks, weighing nearly 40 tons each.  When charging, the plant will stack the blocks around itself higher and higher in a Babel-like tower.  To discharge, the cranes drop the blocks down, generating power from the speedy descent.  This configuration can deliver 4 megawatts of power and store about 35 megawatt-hours of energy.

There isn’t even a factory needed.  The company would deliver a crane from a manufacturer.  The crane will then assemble the blocks onsite using recycled concrete.  Operation is then fully automated.  The system is expected to run for 30 or 40 years.

So far there is only a one-seventh scale demo unit in Switzerland.  But this is a very intriguing idea.

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Energy Vault Wins World Changing Idea Award 2019 from Fast Company for Transformative Utility-Scale Energy Storage Technology

Photo courtesy of Energy Vault.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Dolphins

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We don’t think of heatwaves as something that affects the ocean, but increasingly, as the planet warms, there have been instances where ocean water temperatures become much higher than normal for extended periods of time.  There has been much discussion of this phenomenon with regard to coral reefs where the catastrophic rise in coral bleaching events has been the result.

Recently, a study at the University of Zurich looked at the effects of ocean heatwaves on marine life higher in the food chain.  They studied the well-known dolphin population in Shark Bay, Western Australia.

In early 2011, a heatwave caused water temperatures in Shark Bay to rise more than 4 degrees above the annual average for an extended period.  This led to a substantial loss of seagrass, which is a driving factor in the Shark Bay ecosystem.

The researchers investigated how this environmental damage affected survival and reproduction of dolphins, using long-term data on hundreds of animals collected over a ten-year period from 2007 to 2017.

Their analysis showed that dolphins’ survival rate dropped by 12% and female dolphins were giving birth to fewer calves.  That phenomenon that began in 2011 lasted at least until 2017.

The researchers were surprised by the extent and the duration of the influence of the heatwave, especially the fact that the reproductive rate of dolphins had not returned to normal even after 6 years.

This study shows for the first time that marine heatwaves not only affect organisms at the lower levels of the food chain, but also might have considerable long-term consequences for the animals at the top, such as dolphins.

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Climate change is a threat to dolphins’ survival

Photo, posted December 14, 2014, courtesy of Ed Dunens via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Drilling In California

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More than one million acres of public and private land in California may soon be opened up to oil drilling and hydraulic fracturing, according to a plan recently released by the Trump Administration.  The proposal raises environmental concerns, and comes at a time when opposition to oil and gas drilling in the state is growing.  

The plan, put forth by the Bureau of Land Management, would end a five-year moratorium in the state on leasing federal public land to oil and gas developers.  In 2013, a federal judge put the moratorium in place until the environmental risks of hydraulic fracturing, or fracking, could be better evaluated.

Fracking is the process of injecting liquid at high pressure underground in order to crack open rocks and extract oil or gas.  Well-documented risks associated with fracking include air and water pollution, as well as increased risks of oil spills and earthquakes.

Nevertheless, the Bureau of Land Management, which is part of the U.S. Department of the Interior, released its 174-page environmental impact statement with the proposal to open up 1,011,470 acres of land to fossil fuel extraction, impacting the California counties of Fresno, Kern, Kings, San Luis Obispo, Santa Barbara, Tulare, and Ventura. 

Unsurprisingly, the draft plan has been praised by industry groups who say concerns are misguided, and slammed by environmentalists who say the move poses a serious public health risk and could lead to a “fracking frenzy.”

The proposal is now subject to a 45-day period for public comment, after which the Interior Department will determine how to proceed.  A link to weigh in on the proposal can be found here.

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Trump fracking plan targets over 1 million acres in California

Bakersfield Field Office Hydraulic Fracturing Draft Supplemental Environmental Impact Statement

Photo, posted March 14, 2010, courtesy of Mike Baird via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Deepwater Impacts Lingering

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On April 20, 2010, an explosion on the BP-owned Deepwater Horizon drilling rig released an estimated 210 million of gallons of oil into the Gulf of Mexico.  Some of the oil was recovered, burned, or dispersed at sea, while some washed up onto coastal shorelines. 

Now, more than nine years later, a long-term study suggests the oil is still affecting the salt marshes of the Gulf Coast.  A multi-institutional research team began sampling in the region once the spill was contained and continue their work to this day.

The researchers found that heavily-oiled marsh areas remained less healthy than less polluted sites more than six years after the spill.  They fear that complete recovery of these oil-soaked regions will likely take more than a decade. 

But the researchers also discovered that salt marsh grasses play a key role in coastal wetland recovery.  Two plants dominate healthy salt marshes in the Gulf: smooth cordgrass and black needlerush.  Single-celled, plant-like organisms known as benthic microalgae also abound in healthy salt marshes, as do many small invertebrates. 

In heavily-oiled areas, the researchers found that nearly all the plants died, and benthic microalgae and small invertebrate populations declined significantly.  Importantly, however, they also found that it was only after smooth cordgrass started its comeback in these areas that invertebrate populations began to recover.  They noted that these salt marsh grasses provide habitat, bind soil, slow water, facilitate colonization, and fuel the food web. 

Plants are the foundation of and play a crucial role in salt marshes.  The researchers hope these findings will help shape the mitigation strategies of any future oil spills. 

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Continuing impacts of Deepwater Horizon oil spill

Photo, posted April 21, 2010, courtesy of Deepwater Horizon Response via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Shipping And Invasive Species

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The increasing numbers of invasive species around the world are a major driver of biodiversity change and cause billions of dollars in economic damages annually.  Climate change is a major factor in the spread of invasive species, but a new study by McGill University suggests that global shipping growth will far outweigh climate change in the spread of non-indigenous pests to new environments in the coming decades.

One of the most significant ways in which the disparate regions of the world are interconnected is via transportation networks.   The global shipping network is the primary means by which materials and goods are moved worldwide, accounting for over 80% of world trade.  And for this reason, the global shipping network is responsible for much of the introduction of non-indigenous species across the planet.

Living organisms are often transported through ballast water, which is taken up to stabilize cargo vessels.  Other species are transported by biofouling, whereby they attach to the hulls of ships.  Taken together, these two pathways account for anywhere between 60 and 90% of marine bioinvasions.   (Terrestrial invaders are generally moved as a byproduct of shipping, for example by infesting wood packaging material).

The McGill study looked at trends in global shipping and how socioeconomic factors are driving change.  For example, China’s share of global container throughput has gone from 1.4% in 1990 to 20.1% in 2013.  So, the distribution and patterns of shipping have been changing dramatically and with it the spread of non-indigenous species.

Awareness of this issue is increasing.  For example, there have been policy initiatives such as the International Ballast Water Management Convention that is an effort to control bio-invasions through measures such as ballast exchange.  We need to take measures to limit the unintentional spread of species.

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Global forecasts of shipping traffic and biological invasions to 2050

Photo, posted December 3, 2009, courtesy of Roger W via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

High-Tide Flooding And Pollution

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Global sea levels are steadily rising.  They are up 8 inches in the past century and now increasing at an average of 1.3 inches per decade.  As a result, the incidence of high-tide “sunny day” flooding is on the rise, especially along the U.S. East Coast.

Norfolk Virginia experienced fewer than 2 days of high-tide flooding a year in the 1960s; it had 14 in 2017.  Up and down the East Coast, flood days have increased by factors of 5 and more.

This has led to a form of pollution that hasn’t gathered much attention in the past:  when these floodwaters recede, they can carry debris, toxic pollutants and excess nutrients into rivers, bays, and oceans.

In the aftermath of high-tide flooding in Norfolk, Chesapeake Bay was littered with tipped-over garbage cans, tossed-away hamburgers, oil, dirty diapers, pet waste and all manner of other things.  Water that comes up on the landscape takes everything back into the river or ocean with it.

Analysis of tidal flooding along the Lafayette River in Norfolk indicated that just one morning of tidal flooding poured nearly the entire EPA annual allocation of nitrogen runoff for the river – nearly 2,000 pounds – into Chesapeake Bay.  The effects of excess nitrogen in the water are well-known and responsible for the toxic algal blooms that endanger aquatic life as well as human health.

According to the National Oceanic and Atmospheric Administration, high-tide flooding frequency along the southeastern coast of the U.S. rose 160% since 2000.  With the expected continuing rises in sea level, NOAA projects that as many as 85 days of high-tide flooding will occur along the coast by the year 2050.  It’s a big problem.

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As High-Tide Flooding Worsens, More Pollution Is Washing to the Sea

Photo, posted September 20, 2018, courtesy of SC National Guard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Drugs In The Water

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According to a new study published in the journal Environmental Research Letters, concentrations of pharmaceuticals in rivers and lakes have dramatically increased across the globe over the past 20 years.

Traces of medicines get passed into waterways through the excretion of active drugs in human waste, the disposal of unused medicines down drains, and runoff from livestock farms.

The study looked in detail at two specific drugs:   carbamazepine, an anti-epileptic drug, and ciprofloxacin, an antibiotic.   The study found that the risk of ecological damage from the residue from these two drugs was 10 to 20 times higher in 2015 than in 1995.

Chronic exposure to carbamazepine, for example, has been shown to alter feeding behavior and reduce egg viability in zebrafish, as well as reduce reproductive success in crustaceans.  Antibiotics can alter major nutrient cycles and decrease the effectiveness of bacteria-based wastewater treatment systems.

The study, led by researchers from the Netherlands, created a new model estimating concentrations of the two drugs over a 20-year period in 449 aquatic systems around the globe.  The model predicts a relatively high environmental risk in densely populated and dry areas such as the Middle East. 

When the researchers compared the model’s results to samples from four river systems in various locations, they found that the actual drug concentrations were even higher than model results, in some cases by a factor of 10 to 100. 

The new model should act as a guide for a more thorough investigation into pharmaceutical residues in waterways, which pose significant environmental risks all over the world.

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Concentrations of Pharmaceuticals in Freshwater Increasingly Globally

Photo, posted March 22, 2012, courtesy of Rajeev Rajagopalan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Whopping Change

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Burger King, the global hamburger fast food giant, recently made a huge announcement:  Customers will soon have the option to select either a beef patty or a plant-based patty when ordering the iconic Whopper sandwich. 

Burger King’s plant-based patty will be made by Impossible Foods, a California startup founded in 2011 with the explicit goal of decreasing the world’s reliance on animal agriculture.  Impossible Foods signature product, the Impossible burger, has already debuted as a slider in White Castle’s 380 or so stores.  It’s also being added to the menu at all 570 Red Robin locations.  Other plant-based innovators, such as Beyond Meat, have also found some mainstream success.  But the Impossible Whopper and the planned national roll-out at Burger King’s 7,200 locations is the biggest deal to date.

Impossible Foods’ major innovation comes from its use of heme, which is an iron-rich protein that in essence is what makes meat taste like meat.  Impossible Foods cultivates heme directly from plants – soybean plant roots to be exact – and then mass produces it using yeast.  This is then mixed with other plant-based ingredients to achieve the nutty texture of ground beef.

Meat production is one of the biggest single contributors to climate change.  The Impossible burger represents a better choice for the environment.  It requires 87% less water, 96% less land, and produces 89% fewer greenhouse gas emissions when compared with beef burgers.  At Burger King, the Impossible Whopper will have the same amount of protein as the regular Whopper, but 15% less fat and 90% less cholesterol. 

Meatless continues to push into the mainstream.

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Behold the Beefless ‘Impossible Whopper’

Photo, posted November 27, 2018, courtesy of Sarah Stierch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Trouble On The Colorado

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The 1450-mile-long Colorado River begins in the Rocky Mountains and wends its way to the Gulf of California, creating the Grand Canyon along the way, and providing water to some 40 million people.  The amount of Colorado River water promised to users is far more than actually flows between its banks, and that amount is dropping.

An unrelenting drought since 2000 has resulted in the water levels of the two largest reservoirs of Colorado River water – Lake Mead and Lake Powell – being at all-time lows.

Lake Mead, just outside of Las Vegas, is the reservoir of Hoover Dam, which provides power for millions of people in Southern California, Nevada, and Arizona.  The last time Lake Mead was full was in 1983.  It has slowly declined and now is 40% full.

If the lake level drops another 7 feet to 1075 feet above sea level, it will trigger a Tier 1 declaration, mandating cuts to water allocations to Arizona and other states.  If the level drops to 1050 feet, it would reach Tier 2 at which point Hoover Dam would have to stop generating electricity because water levels would be too low to flow through it.  If the lake level drops all the way to 895 feet, it would be below the level at which water can be piped out of it.  This is known as the “dead pool”.

These scenarios are no longer doomsday fantasies.  Water managers in the Southwest see the writing on the wall and are busy making contingency plans and developing ways to use less water from the Colorado River.  The booming city of Phoenix in particular is hard at work finding alternative ways to provide water for its millions of citizens.  On the Colorado, drought in the new normal.

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On the Water-Starved Colorado River, Drought Is the New Normal

Photo, posted October 24, 2016, courtesy of Sharon Mollerus via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Glaciers And Water Supply

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The world has roughly 150,000 glaciers covering about 200,000 square miles of the earth’s surface.  Over the last 40 years they’ve lost the equivalent of a layer of ice 70 feet thick.  Most of them are getting shorter as well.  Some have shrunk to nothing; many smaller glaciers in places like the Rockies and the Andes have disappeared entirely.

Glaciers represent the snows of centuries, compressed over time to form flowing rivers of ice.  They always change over time, accumulating snow in winter and losing ice to melting in summer.  But in recent times, the warming climate has allowed the melting to outpace the accumulation.

Much of the discussion about the retreating glaciers relates to sea level rise, catastrophic floods, debris flow, and the effects on rivers and ecosystems.

But in some places, the biggest impact of the loss of glaciers is on the supply of water for people and agriculture.  In Kazakhstan, Almaty, the country’s largest city depends on glacier-fed rivers for drinking water for its 2 million people and for irrigation water for crops.  All across the Tibetan Plateau and the Himalayan and Karakmoram mountain ranges, hundreds of millions of people rely on glacier-fed rivers for their water supplies. 

A melting glacier can at first increase stream flow but eventually reaches a tipping point and meltwater begins to taper.  In the short term, the melting glaciers may provide increased amounts of water coming down from the mountains, but eventually the flow in the rivers will begin to decline and populations will face a crisis.

It will be essential for people in many places to carefully plan for their future water needs in a changing world.

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Glaciers Are Retreating. Millions Rely on Their Water.

Photo, posted September 16, 2011, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Hydrogen From Water And Sun

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There are research efforts around the world seeking ways to produce hydrogen starting from water and using clean energy.  Finding an economical and scalable way to do this is a key to the so-called hydrogen economy.

A recent study at Argonne National Laboratory makes use of a chemical reaction pathway central to plant biology to create a process that converts water into hydrogen using energy from the sun.

The process combines two membrane-bound protein complexes to perform the conversion of water molecules into hydrogen and oxygen.

The first protein complex, which the researchers call Photosystem I, is a membrane protein that uses energy from light to feed electrons to an inorganic catalyst that makes hydrogen.  But this represents only half of the overall process.

A second protein complex that they call Photosystem II uses energy from light to split water and take electrons from it.  The electrons are then fed to Photosystem I.

The two protein complexes are embedded in thylakoid membranes, which are like those found inside the oxygen-creating chloroplasts in plants.  This membrane is an essential part of pairing the two photosystems.  It supports both of the photosystems and provides a pathway for transferring electrons between the proteins.

The researchers also make use of a synthetic catalyst made from nickel or cobalt that replaces expensive platinum catalysts used in conventional water-splitting schemes.  Combining the light-triggered transport of electrons with the synthetic catalyst results in what the researchers call the “Z-scheme”, an adaptation of photosynthesis to produce hydrogen.

The next step is to incorporate the scheme into a living system which the researchers hope will lead to a practical system for hydrogen production.

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Discovery adapts natural membrane to make hydrogen fuel from water

Photo, posted December 25, 2017, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fast Food And Climate Change

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A coalition of global investors is urging some of the largest fast food companies to reduce greenhouse gas emissions. The group, which has approximately $6.5 trillion under management, wants the fast food chains to reduce the carbon footprint of their meat and dairy supply chains. 

The global fast food sector is reportedly worth a whopping $570 billion annually.  The coalition has targeted some of the most notable contributors to that figure, including McDonald’s, KFC, Domino’s, Wendy’s, Burger King, Pizza Hut, and Chipotle.

According to the investors, animal agriculture is one of the world’s highest-emitting sectors without a low-carbon plan.  If left unchecked, emissions from animal agriculture alone would contribute 70% of the total worldwide target for emissions in 2050 that would keep the global rise in temperature below 2C.  Animal agriculture also uses an estimated 10% of annual global water flows.

In their letter to the fast food giants, the investors are calling on the companies to implement clear requirements for suppliers of animal proteins to report and reduce their greenhouse gas and freshwater impacts.  They want fast food companies to publish quantitative, time bound targets for reductions, and commit to publicly disclose the progress on these targets. 

Climate change is increasingly a factor for investors when evaluating market risk.  This investor letter comes just weeks after the EAT-Lancet commission report was published, in which their experts suggest that a sustainable diet for the planet by 2050 will require a 90% reduction in red meat and milk consumption.   

Fast food may need to slow down. 

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Fast food giants under fire on climate and water usage

The EAT-Lancet Commission on Food, Planet, Health

Photo, posted May 19, 2014, courtesy of Mike Mozart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Disease On Coral Reefs

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The warming oceans have led to bleaching events in coral reefs around the world, but bleaching is not the only problem corals face.  Disease outbreaks are also becoming more frequent, severe, and widespread.

Many factors are contributing to the problem, including pollution and nitrogen runoff from fertilizers and coastal sewer and septic systems.  However, the key culprit is likely the steadily increasing ocean temperatures, which are the cause of coral bleaching.  Elevated water temperatures can cause coral polyps to expel the algae that sustains them and gives them color. 

According to scientists, bleaching makes corals more susceptible to illness.  In the Caribbean, a coral disease hotspot, about 80% of coral cover has disappeared, largely from outbreaks of “white band disease”, so called because of a white band of dead tissue that forms in affected corals.  Two crucial reef-building species, elkhorn and staghorn coral, are now nearing extinction in the regions.  The reef extending along the Florida coastline is the third largest reef ecosystem in the world and nearly 35% of it has been lost to disease.

Estimates are that disease outbreaks have wiped out at least 6% of the corals on the Great Barrier Reef in Australia.  In that region, diseases are more prevalent in areas where corals were damaged by fishing and other human activity because wounded coral provides an entry point for pathogens and bacteria.

In the face of climate change and mounting disease outbreaks, scientists are scrambling for solutions to stave off catastrophe.  Assisting the migration of hardier coral species and breeding so-called “super corals” are among the strategies being pursued.  It is unknown whether these and other forms of intervention can be used on a wide enough scale to really make a difference.

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Web Links

As Disease Ravages Coral Reefs, Scientists Scramble for Solutions

Photo, posted November 29, 2012, courtesy of Robert Linsdell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Misconceptions About Electric Cars

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Tesla’s Model 3 was one of the best-selling cars in the United States last year, eclipsing all but a handful of sedans.  This was the first time that an electric car had that honor and is indicative of how electric cars are finally becoming mainstream.  A host of other new electric models from multiple manufacturers will be the entering the market over the next couple of years.

Despite all of this progress, there is still a great deal of misinformation about electric cars.  A new study commissioned by Volkswagen revealed some of the widespread misconceptions about the vehicles.

Some people believe that electric cars can’t be driven through puddles.  Nearly one in five people believe that electric cars slow down as the battery depletes.  Many people believe that electric cars are fundamentally less safe than gas-powered cars.

More generally, people are unaware of how far current electric cars can drive on a charge.  More and more models can go 200 and even over 300 miles between charging sessions.  People also don’t know how quickly cars can charge up either.  Fast chargers like Tesla’s Superchargers can add 200 miles worth of charge in about 20 minutes.  And people don’t know what it costs to charge electric cars.  In most places, it is only a fraction of what it costs to drive the same distance using gasoline.

Despite their limited knowledge about electric cars, the 2,000 people surveyed in Britain were positively disposed towards them with nearly 6 in 10 saying that they would like to own an electric car some day and would even consider one as their next vehicle.

Electric cars will become more familiar and less exotic as more and more of them are on our roads and highways.

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Web Links

Major misconceptions prevent drivers from buying electric cars, study claims

Photo, posted April 6, 2018, courtesy of Brian Doyle via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

https://www.independent.co.uk/news/uk/home-news/electric-cars-misconceptions-battery-charging-safety-volkswagen-study-results-a8700536.html

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