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Finding peatlands

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Peatlands are a special kind of wetland that have enormous potential for helping to mitigate climate change.  They are great at capturing carbon because their constantly soggy soils deprive decomposer organisms of the oxygen they need to break down dead plants.  Living plants absorb carbon dioxide from the atmosphere and incorporate the carbon into their tissues.  When plants die, decomposers like bacteria digest the plant matter and release the carbon dioxide back into the atmosphere.

Researchers from the University of California Santa Cruz found that the average per-area carbon densities in peatlands in Colombia are four to ten times higher than those in the Amazon rainforest.  This agrees with other studies around the world.  On a global scale, peatlands cover only 3% of land areas but store more carbon than all the world’s trees.  Peatlands are unsung heroes helping to reduce the impact of fossil fuel emissions.

Peatlands can only store carbon if they remain constantly wet.  When they are drained for agriculture or other development, decomposer organisms get back to work digesting organic matter and releasing carbon dioxide back into the atmosphere.

A major challenge in protecting peatland is finding them.  They are often hard to distinguish from other types of wetlands. 

The Santa Cruz researchers have been identifying and locating peatlands in Colombia, where decades of civil war had made many parts of the country inaccessible for research.  Finding and protecting peatlands there and in many other places around the world is an important task in the battle against climate change.

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Colombia’s peatlands could be a crucial tool to fight climate change. But first we have to find them.

Photo, posted January 2, 2018, courtesy of Roni Ziade / U.S. Forest Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

More eco-friendly desalination

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There are about 16,000 operational desalination plants, located across 177 countries, which generate an estimated 25 billion gallons of fresh water daily.

For every gallon of drinking water produced at a typical desalination plant, one and a half gallons of brine are produced.  Much of it is stored in ponds until the water evaporates, leaving behind solid salt or concentrated brine for further treatment.  There are various other techniques for concentrating brines, but they are energy-intensive and environmentally problematic.  The process called electrodialysis uses electrified membranes to concentrate salts. 

Water flows into many channels separated by membranes, each of which has the opposite electrical charge of its neighbors.  Positive salt ions move towards negatively charged electrodes and negative ions move toward positive electrodes.  Two streams result, one containing purified water and one containing concentrated brine.

This eliminates the need for evaporation ponds, but existing electrodialysis membranes either result in leakage of salts into the environment or are too slow, making the process impractical for large-scale use.

Researchers at the University of Michigan have developed a new kind of membrane for electrodialysis.  The new membranes don’t leak and are ten times more conductive than those on the market today which means that they can move more salt using less power.  The membranes can be customized to suit a broad range of water types, which may help make desalination a more sustainable solution to the world’s growing water crisis.

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Making desalination more eco-friendly: New membranes could help eliminate brine waste

Photo, posted February 4, 2012, courtesy of David Martinez Vicente via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tracking atmospheric mercury

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Atmospheric mercury is a toxic pollutant released into the air from natural sources—such as volcanoes and wildfires—and from human activities like coal burning and gold mining.  Once in the atmosphere, mercury can travel long distances before settling onto land or into water, transforming into toxic forms that threaten ecosystems and human health.

But tracking atmospheric mercury is a costly and challenging endeavor, requiring specialized equipment and trained personnel. Active monitors, which pump air to collect mercury, are expensive and need electricity, while passive samplers, using activated charcoal for remote areas, cost up to $100 each.

Researchers from Cornell University have found a cheap method for tracking toxic atmospheric mercury near gold mining sites throughout the Global South: wild fig trees.  In the study, which was conducted in the Peruvian Amazon and recently published in the journal Frontiers in Environmental Science, the research team found that the rings in wild fig trees can serve as natural archives of atmospheric mercury, capturing and preserving historical pollution levels over time.

The technique itself is not actually new.  Previous studies have used tree rings to track mercury pollution from coal combustion, particularly in Canada. But the research team wanted to test this method in regions of the Global South, where mercury emissions from gold mining are widespread.

According to the research team, wild fig trees might soon serve as an important biomonitoring tool, helping scientists better understand how mercury disperses across landscapes and through time.

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Tree rings track atmospheric mercury cheaply

Photo, posted November 13, 2012, courtesy of Steve Kessler via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Hot water in Boise

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Boise is the capital of Idaho, and the Idaho Statehouse is the only one in the United States to use geothermal heat.  Geothermal heating is possible in Boise because of fault lines that expose its groundwater to hot rocks.  The underground water supply in Boise is heated to around 170 degrees Fahrenheit.  It is the basis of the largest municipally-run geothermal system in the country.

People in Boise began using this natural resource to supply heat to buildings in the 1890s by drilling wells into aquifers that yielded hundreds of thousands of gallons of piping hot water a day.  The water heated pools and public baths, a Victorian mansion, and, eventually, hundreds of homes in what was called the Boise Warm Springs Water District.

The number of buildings that the city of Boise heats with its geothermal resource has grown more than sixfold over the past 40 years.  The water is drawn from wells in the nearby foothills and pumped into a closed-loop network of pipes that reach into buildings.  In each building, the geothermal heat is transferred to water in separate adjoining pipes that distribute the heat throughout the building.  The well water goes back to the aquifer to be heated again.

Today, there are four separately run geothermal water systems in Boise.  One is run by the city, another by the Boise Warm Springs District, and two others that serve the Capitol and Veterans Affairs Buildings.

In 2024, city officials calculated that using geothermal heat reduced annual carbon dioxide emissions by 7,000 tons, the equivalent of removing 1,500 gas-powered cars from the road each year.

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They’re in Hot Water in Idaho. Here’s Why That’s a Good Thing.

Photo, posted May 26, 2010, courtesy of Jason W via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

An eco-friendly detergent

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Household products such as laundry detergents and dishwasher tablets are an indispensable part of everyday life, but such products contain all sorts of chemicals that have undesirable properties.  Many are difficult to break down when they enter the environment, and some add nutrients that trigger environmentally harmful algal blooms.   The ingredient lists for even what are described as environmentally friendly cleansing products can be filled with lots of polysyllabic chemicals with unknown potential impacts.  Detergents made from harmless stuff are often difficult to make, hard to rinse off, and sometimes potentially damaging to fabrics.

Researchers at Tianjin University in China have developed an environmentally friendly detergent made of tiny wood fibers and corn protein that removes stains from clothes and dishes as well as commercial products.

The researchers combined cellulose nanofibers from wood with zein protein, which is taken from corn, to produce an emulsion.  The cellulose can attract and repel water and can form emulsions and attract various kinds of stains.  The zein protein helps to stabilize the emulsion and trap oils.

They tested the new detergent by cleaning cotton cloth and dishes stained with ink, chili oil, and tomato paste.  They compared the results against commercial laundry detergent and dish soap.  Their new detergent was somewhat less effective than the commercial products when used at 1% concentration but was more effective when used at a 5% concentration. 

The results suggest that this natural detergent could be an efficient, cost-effective, and sustainable alternative to the synthetic cleaning agents that currently dominate the market.

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Researchers create eco-friendly detergent from wood fiber and corn protein

Photo, posted July 31, 2009, courtesy of Mei Anne Mendoza via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Relocating native plants

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Climate change is endangering many native plant species.  As the climate warms, many species will need to establish themselves in new places that are more hospitable than their historic ranges.  But many native plants in the U.S. cannot move themselves by natural forces quickly enough to avoid climate-change driven extinction.  For such plants to survive into the future, they will need human help to move into adjacent areas, a process called “managed relocation.”

Such a process has its problems.  There is no guarantee that a plant will thrive in a new area.  On the other hand, relocating plant species historically has often had disastrous consequences.  Consider, for example, the story of kudzu in the American south.

Researchers at the University of Massachusetts Amherst have studied this problem in detail and reported the results in the journal Global Change Biology.

The issue is how to help plants move successfully without their causing harm in their new locations.  The study found that some plant traits can lead to success and some to ecological disaster.  In some cases, the same traits that help plants to establish themselves in a new location make them powerful invasive species.  Traits like having a large size predispose a plant to not only establish itself but spread wildly. 

The study recommends that people managing relocation need to focus on plants whose traits they have determined to be conducive to successful relocation but more unlikely to cause harm in their new environment. 

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If Native Plants Are Going to Survive Climate Change, They Need Our Help to Move—Here’s How to Do It Safely

Photo, posted August 17, 2012, courtesy of Joshua Mayer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Scrubbers to clean up shipping

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Cargo ships are significant sources of global air pollution because of their fuel oil.  Most ships burn heavy fuel oil that is loaded with sulfur, so when it is burned it produces noxious gases and fine particles that can harm human health and the environment.  The International Maritime Organization enacted a mandatory cap of 0.5% for the sulfur content of marine fuels in 2020.  Heavy fuel oil has a sulfur content of 2 to 3 percent.

Shipping companies can comply by burning low-sulfur fossil fuels or biofuels, but these are much more expensive.  The most feasible and cost-effective option is to install exhaust gas cleaning systems, known as scrubbers. 

A scrubber is a huge metal tank installed in a ship’s exhaust stack.  Seawater is sprayed from nozzles to wash the hot exhaust.  The seawater reacts with sulfur dioxide and converts it to sulfates, which are environmentally benign natural components in seawater.

A study by the National Technical University of Athens in Greece has performed a lifecycle assessment of the use of scrubbers and has found that burning heavy fuel oil with the use of scrubbers can match or even surpass the benefits of using low-sulfur fuels.

Producing low-sulfur fuel causes additional greenhouse gas and particulate matter emissions in refineries. On the other hand, scrubbers reduce sulfur dioxide emissions by 97% and dramatically reduce other pollutants as well.

The study shows the importance of incorporating lifecycle assessments into evaluation of environmental impact reduction policies.

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Study: Burning heavy fuel oil with scrubbers is the best available option for bulk maritime shipping

Photo, posted August 3, 2015, courtesy of Lotsemann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Removing microplastics from water

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Microplastics come from the breakdown of larger plastics in the environment as well as from direct use in various products such as certain cosmetics.  They are found everywhere, from oceans and mountain peaks to the air and water, and alarmingly, in our bodies.  They are ingested by all sorts of organisms, from tiny plankton to fish and marine mammals.  Microplastics just don’t go away.  They don’t biodegrade so they simply accumulate in the environment.

Researchers at North Carolina State University have recently demonstrated proof of concept for a system that actively removes microplastics from water.  Such a system has the potential for helping to cleanse oceans and other bodies of water from the tiny plastic particles.

The system makes use of soft dendritic colloids, which are tiny particles that have the ability to stick to just about any surface.  These sticky particles can attract microplastics and grab them, even in wet and salty conditions.  The colloids are made from chitosan, a harmless and biodegradable polymer made from processed shellfish waste.

The researchers produced small pellets of the colloids that also contain small amounts of magnesium, which makes them bubble up and rise to the surface of water.  The pellets are coated with a gelatin layer, which blocks the magnesium.  As the gelatin gradually dissolves away, the pellets collect microplastics.  Eventually, the result is a microplastic-laden scum that rises to the surface where it can be skimmed away.

The scum itself can be bioprocessed into more chitosan that can create more of these microcleaner pellets to then capture more microplastics.  The researchers are investigating how the process can be scaled up to become a valuable tool in dealing with the microplastics problem.

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New Water Microcleaners Self-Disperse, Capture Microplastics and Float Up for Removal

Photo, posted January 17, 2018, courtesy of Bo Eide via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The dangers of deep sea mining

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The White House is considering an executive order that would fast-track permitting for deep-sea mining in international waters and allow mining companies to bypass a United Nations-backed review process.

Deep sea mining is the extraction of minerals from the seabed in the deep ocean.  Most of the interest is in what are known as polymetallic nodules, which are potato-sized mineral deposits that have built up in layers over thousands of years. They are located several miles below the surface, primarily in what is called the Clarion-Clipperton zone, which is an environmental management area of the Pacific Ocean about halfway between Mexico and Hawaii.

A new multiyear study led by UK’s National Oceanography Center and published in the journal Nature found that the site of a deep-sea mining test in 1979 still showed lower levels of biodiversity than in neighboring undisturbed sites 44 years later.

Much is not known about the undersea nodules.  We know that they produce oxygen.  If the nodules are removed, will that reduce the amount of oxygen in the deep sea and affect the organisms that live there?  If mining occurs, what effect will the metal-containing sediment plumes churned up by the mining process have? 

The nodule fields sustain highly specialized animal and microbial communities.  More than 20 billion tons of nodules are estimated to lie on the seabed of the Clarion-Clipperton Zone.  If large-scale mining takes place, and there is much interest in that happening, it is important to find out what the impact will be on the ocean and its ecosystems because it is likely to be largely irreversible.

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Deep sea mining for rare metals impacts marine life for decades, scientists say

Photo, posted September 4, 2014, courtesy of James St. John via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The warmer, greener Arctic and greenhouse gas

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About 15% of the Northern Hemisphere is covered by permafrost.  Permafrost is soil and sediment that has remained frozen for long periods of time, in some cases as much as 700,000 years.  It contains large amounts of dead biomass that has accumulated over millennia and hasn’t fully decomposed.  Therefore, permafrost is an immense carbon sink.

The Arctic is warming four times faster than the rest of the planet and, as a result, thawing permafrost is becoming a carbon source.  As warming continues, ice is melting, and vegetation is spreading.    A new study, published in Nature Climate Change, looked at the state of the Arctic and boreal north from the period 1990 until 2020.  The study found that although half of the Arctic region has been growing greener, only 12% of those green areas are actually taking up more carbon.  For one thing, the growth of forests means that there is more fuel for wildfires which are increasingly common.

A study of lakes in West Greenland found that thousands of crystal blue lakes have turned brown during record heat spells.  Runoff from melting permafrost made the lakes opaque killing off plankton that absorb carbon dioxide.  Meanwhile, plankton that release carbon dioxide multiplied.  So, these lakes went from being carbon sinks to being carbon sources.

As the northern latitudes warm, ice and permafrost are melting, vegetation is spreading, and the region is becoming a source of heat-trapping gas after having been a place where carbon has been locked away for thousands of years.  According to the Nature Climate Change study, roughly 40% of the Arctic is now a source of carbon dioxide.

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Warmer, Greener Arctic Becoming a Source of Heat-Trapping Gas

Photo, posted October 14, 2024, courtesy of Christoph Strässler via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The largest iceberg runs aground

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The largest iceberg in the world, which has been slowly drifting for nearly 5 years, has finally come to a halt.  The iceberg – called the unexciting name A-23A – came into existence in 1986 when it broke off from another iceberg A-23 that had calved or torn off from Antarctica earlier that year.  For decades, A-23A sat in the Weddell Sea, east of the Antarctic Peninsula.  Then, in 2020, it came loose from the seafloor and began to move.  By 2023, it finally left Antarctic Waters.

Late last year, it began spinning in place caught in an ocean current called a Taylor column.  Finally, it headed for South Georgia, a British-owned island that is home to a couple dozen people and lots of seals and penguins.  A-23A is now stuck on the continental shelf, about 50 miles from the island.

A-23A is around 1,300 square miles in area.  By comparison, New York City is 300 square miles.

Four years ago, a large iceberg called A-68A also came to ground in the vicinity of South Georgia.  It quickly broke apart and ultimately added 150 billion metric tons of fresh water to the ocean as well as various nutrients.  A-23A is also likely to succumb to the warmer waters, winds, and currents it now encounters and will affect the flora and fauna in the area.

The climate is changing and is impacting how ice shelves melt.  Calving and the creation of mammoth icebergs are a normal part of the lifecycle of polar ice sheets, but we are likely to see even more events like this in the future.

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World’s Largest Iceberg Runs Aground

Photo, posted January 29, 2011, courtesy of Drew Avery via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastic from food waste

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Plastic waste management is a complicated business.  Most methods of recycling or breaking down plastic are costly and harmful to the environment.  The most common biodegradable alternatives – like paper straws – are less than ideal replacements.

There are many approaches to creating biodegradable plastics using feedstocks like seaweed, sugarcane, and other plant matter.  However, the resulting plastics often fall short compared with conventional petroleum-based plastics.

One type of bioplastic that is gaining popularity is polyhydroxyalkanoates, or PHA.  PHA is a plastic produced by microorganisms.  It is fully compostable or biodegradable but in other ways but looks, feels, and functions like regular plastic but without the environmental drawbacks.

PHA can be made using bacterial fermentation of a variety of feedstocks such as vegetable oils, sugars, starches, and even methane and wastewater.

Researchers at a startup from the University of Waterloo in Canada called MetaCycler BioInnovations have developed a process for producing PHA based on bacteria that has been engineered to convert waste from milk and cheese production.  This solution upcycles waste from the dairy industry into cost-effective, sustainable bio-based plastics. 

PHAs can be tailored to have a wide range of properties ranging from being rigid and tough to being quite flexible.  Therefore, they can be suitable for many applications including packaging, agricultural films, and consumer goods. 

The Waterloo technology is a way to tackle the problems of both food waste and plastic pollution with one solution.

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Turning food waste into a new bioplastic

Photo, posted December 10, 2017, courtesy of Leonard J Matthews via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Rising seas are destroying buildings

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Alexandria is the second largest city in Egypt and is the largest city on the Mediterranean coast.  Its history goes back over 2,300 years and it was once home to a lighthouse that was among the Seven Wonders of the Ancient World and a Great Library that was the largest in the ancient world.  The modern city has more than 6 million residents but still has many historic buildings and ancient monuments.  But perhaps not for long.

Rising seas and intensifying storms are taking a toll on the ancient port city.  For centuries, Alexandria’s historic structures have endured earthquakes, storm surges, tsunamis, and more.  They are truly marvels of resilient engineering.  But now, climate change is undoing in decades what took millennia for humans to create.

Over the past two decades, the number of buildings collapsing in Alexandria has risen tenfold.   Buildings are collapsing from the bottom up as a rising water table weakens soil and erodes foundations.  Since 2001, Alexandria has seen 290 buildings collapse.  Comparing present-day satellite imagery with decades-old maps, the authors of a study by the Technical University of Munich have tracked the retreat of Alexandria’s shorelines to determine where seas have intruded into groundwater. The authors say that more than 7,000 buildings in Alexandria are at risk.  They call for building sand dunes and planting trees along the coast to block encroaching seawater.

The true cost of this gradual destruction goes far beyond bricks and mortar.  This is the gradual disappearance of historic coastal cities.  Alexandria is a warning for such cities around the world.

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In This Storied Egyptian City, Rising Seas are Causing Buildings to Crumble

Photo, posted September 11, 2012, courtesy of Sowr via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Amphibians and climate change

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Amphibians are a group of vertebrate animals that include frogs, toads, and salamanders. They are unique for their ability to live both in water and on land during different stages of life. Amphibians play a crucial role in ecosystems, often serving as both predators and prey in food webs.

Amphibians are the world’s most at-risk vertebrates, with more than 40% of species listed as threatened.  They are cold-blooded creatures and rely on external sources to regulate their body temperature.  But needing to regulate their body heat this way makes amphibians particularly vulnerable to temperature change in their habitats. 

Researchers from the University of New South Wales in Australia can now predict the heat tolerance of 60% of the world’s amphibian species.  This new tool will allow scientists to better identify which amphibian species and habitats will be most impacted by climate change.  

The study’s landmark findings, which were recently published in the journal Nature, found that 2% of amphibian species are already exposed to overheating in shaded terrestrial conditions.  According to the research team, a 4°C global temperature increase could push 7.5% of amphibian species beyond their physiological limits. 

Local amphibian extinctions can trigger ecological repercussions, including reshuffling community compositions, eroding genetic diversity, and impacting the food chain and overall ecosystem health.

The researchers highlight the importance of vegetation and water bodies in protecting amphibians during heat waves, and emphasize the need to provide adequate water and shade during future conservation efforts. 

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The pot is already boiling for 2% of the world’s amphibians: new study

Photo, posted October 8, 2011, courtesy of Dave Huth via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Green grout for stabilizing buildings

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We are all familiar with the grout that is used for tiles in our homes. We are less familiar with grout that is used to stabilize the soil beneath buildings.  Grouting is a process of ground improvement by injecting materials that can fill voids and cracks, strengthen and increase the bearing capacity of soil, and reduce permeability.

Traditional grouting methods have environmental downsides.  Most often, silica-based chemical grouts are used, and they are produced through energy-intensive processes that contribute substantially to carbon dioxide emissions.  As is the case for all materials and practices of the construction industry, developing sustainable, low-emission alternatives to conventional grouting materials has become an important priority.

Researchers from the Shibaura Institute of Technology in Japan have developed an innovative new grout material called Colloidal Silica Recovered from Geothermal Fluids.  This grout material enhances soil stabilization and simultaneously reduces the environmental impact of geothermal energy harvesting.

Geothermal energy production generates large amounts of silica-rich waste fluids which creates challenges for its maintenance and disposal.  The new grout repurposes this waste material thereby transforming an industrial byproduct into a valuable construction material.

The new grout material is particularly valuable in earthquake-prone regions, where soil stabilization is essential in preventing structural damage during seismic events.  In addition, the grout’s superior water-sealing properties makes it ideal for underground construction projects like tunnels, subways, and basements.  The new grout in an important step for the construction industry’s efforts to achieve carbon neutrality.

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From Waste to Wonder: Revolutionary Green Grout for Sustainable Construction Practices

Photo, posted July 8, 2011, courtesy of MTA Construction & Development Mega Projects via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Recycling lithium-ion batteries

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Lithium-ion batteries are used to power computers and cellphones and, increasingly, vehicles.  The batteries contain lithium as well as various other valuable metals such as nickel, cobalt, copper, and manganese.  Like other batteries, lithium-ion batteries have a finite lifetime before they can no longer perform their intended function.

Recycling lithium-ion batteries to recover their critical metals is an alternative to mining those metals.  A recent study by Stanford University analyzed the environmental impact of obtaining those metals using lithium-ion battery recycling compared with mining.  They found that the recycling process is associated with less than half of the greenhouse gas emissions of conventional mining.  The process uses about one-fourth of the water and energy of mining new metals.  North America’s largest industrial-scale lithium-ion battery recycling facility is Redwood Materials, located in Nevada, which uses a clean energy mix that includes hydropower, geothermal, and solar power.

These calculated advantages are associated with recycling batteries that have been in use.  The advantages are even greater for recycling scrap:  defective material from battery manufacturers.

The advantages of recycling are dependent on the sources of electricity at the recycling plant and the availability of fresh water. 

At present, the U.S. recycles about half of its available lithium-ion batteries.  By comparison, 99% of lead-acid batteries (like those found in cars and trucks) have been recycled for decades.  As the supply of used lithium-ion batteries continues to increase, it is important for the availability of industrial-scale battery recycling to keep pace. 

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Recycling lithium-ion batteries delivers significant environmental benefits

Photo, posted May 7, 2020, courtesy of Mark Vletter via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The importance of shallow water

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Vacationers love beaches with shallow water.  They are great for families with small kids and for less confident swimmers.  Such beaches often attract intense coastal development.  However, they are also fragile habitats that are disappearing around the world.

A new study led by the University of South Florida highlights the need to protect these marine ecosystems.  Shallow coastal waters are known as tidal flats, and they are critical to global seafood supplies, local economies, and overall marine health.  Shallow water ecosystems are interlinked with other marine habitats and are vital for the lifecycle of marine species far from shore.

Shallow water ecosystems are at risk not only from coastal development, but from harmful algal blooms triggered by human activity, from marine heatwaves, and from boats operating in sensitive habitats such as seagrass meadows. These habitats contribute millions of dollars to local economies such as those in Florida but there is not much direct habitat managements in place to protect these ecosystems.

The University of South Florida study, published in the journal Fisheries, enumerated ten core strategies that boaters, anglers, wildlife managers, and policymakers can adopt to prioritize and preserve shallow marine ecosystems from humans and from increasingly powerful weather events.  Foremost among these efforts are the protection of key fish species, such as tarpon, whose protection would benefit additional species that use the same habitats.

Habitat management and restoration should be essential concerns for coastal communities to provide long-term benefits for both themselves and for the marine life that depends on shallow-water habitats.

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Why shallow water at the beach is more important than you might realize

Photo, posted February 14, 2018, courtesy of Marcelo Campi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Trapping carbon with rocks

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Many experts say that combating global warming will require both drastically reducing the use of fossil fuels and permanently removing billions of tons of CO2 already in the atmosphere.  Developing practical, large-scale technologies for carbon removal is a significant challenge.

There is a nearly inexhaustible supply of minerals that are capable of removing carbon dioxide from the atmosphere, but they don’t do it quickly enough to make a significant dent in the ever-growing supply in the atmosphere.  In nature, silicate minerals react with water and atmospheric CO2 to form minerals in the process called weathering.  But this chemical reaction can take hundreds or even thousands of years.

Researchers at Stanford University have developed a new process for converting slow-weathering silicates into much more reactive minerals that capture and store carbon quickly.  The new approach resembles a centuries-old technique for making cement.  They combine calcium oxide and another common mineral containing magnesium and silicate ions in a furnace.   The result are new materials that, when exposed to water, quickly trap carbon from the atmosphere.

In their experiments, the carbonation process took weeks to months to occur, thousands of times faster than natural weathering.

The idea would be to spread these materials over large land areas to remove CO2 from the air.  Meaningful use for trapping carbon would require annual production of millions of tons.  But the same kiln designs used to make cement could produce the needed materials using abundant minerals found in many places.  In fact, the required minerals are often common leftover materials – or tailings – from mining.

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Scientists discover low-cost way to trap carbon using common rocks

Photo courtesy of Renhour48 via Wikimedia.

Earth Wise is a production of WAMC Northeast Public Radio

Sea turtles and climate change

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Life is a struggle for survival from the moment a sea turtle hatches.  In fact, only one sea turtle out of every 1,000 typically reaches adulthood as a result of natural predators and other challenges.  Those fortunate enough to make it to adulthood face serious threats from humans. For example, sea turtles are hunted for their meat, eggs, and shells in some regions. Their beach habitats get developed. Harmful marine debris and oil spills pollute their waters and beaches.

Now, climate change is exposing sea turtles to even greater threats.  Rising sea levels and stronger storms threaten to erode and destroy their nesting beaches. Warming oceans disrupt currents, potentially exposing sea turtles to new predators, and damaging the coral reefs that some depend on to survive.

As these environmental challenges intensify, sea turtles are beginning to adapt in surprising ways.  According to a new study by researchers from the University of Exeter in England and the Society for the Protection of Turtles in Cyprus, sea turtles are responding to climate change by nesting earlier.  Researchers monitoring nesting green and loggerhead turtles in Cyprus have discovered they are returning to their regular nesting spots earlier each year to compensate for rising temperatures.

Temperature plays a crucial role in determining the biological sex of sea turtles.  Warmer nest temperatures produce more female hatchlings than males.

But at least for now, sea turtles seem to be doing enough to ensure their eggs continue to hatch by nesting earlier in more ideal temperatures.  While this is good news, there’s no guarantee that it will continue. 

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Turtles change nesting patterns in response to climate change

Photo, posted December 20, 2021, courtesy of Cape Hatteras National Seashore via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Sand mining and the environment

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Sand mining is the world’s largest mining endeavor.  It is responsible for 85% of all mineral extraction.  It is also the least regulated, possibly the most corrupt, and likely the most environmentally destructive.  Sand is the second-most exploited natural resource in the world after water.  Its global use has tripled in the past two decades.  More than 50 billion tons of sand is extracted from the environment each year.

Sand plays a critical role in much of human development around the world.  It is a key ingredient of concrete, asphalt, glass, and electronics.  It is relatively cheap and relatively easy to extract.  But we use enormous amounts of it.

Sand mining is a major threat to rivers and marine ecosystems.  It is linked to coastal erosion, habitat destruction, the spread of invasive species, and damage to fisheries. 

The harm from sand mining is only beginning to attract widespread attention.  A recent study by an international group of scientists published in the journal One Earth identifies        threats posed by sand mining.  Sand extraction in marine environments remains largely overlooked, despite sand and sediment dredging being the second most widespread human activity in coastal areas after fishing.

Sand is generally seen as an inert, abundant material, but it is an essential resource that shapes coastal and marine ecosystems, protects shorelines, and sustains both ecosystems and coastal communities.  Sand extraction near populated coastlines is particularly problematic as climate change makes coastlines increasingly fragile.

Like all other resources on our planet, even sand cannot be taken for granted.  It must be responsibly managed.

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The rising tide of sand mining: a growing threat to marine life

Photo, posted February 7, 2013, courtesy of Pamela Spaugy / U.S. Army Corps of Engineers via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)