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Restored wetlands and climate

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Forests are well-known to be major storehouses of carbon in the environment.  Less known but also extremely important are peatlands and wetlands and, like forests, both have suffered declines as a result of human activity.  And, like forests, both are seeing efforts at restoration.

Restoring peatlands has the drawback that it initially causes a spike in methane emissions, and it therefore takes a long time for them to have a net positive effect on the climate after they are restored. 

In a new study by RMIT University in Australia, it was found that reviving floodplain wetlands reduces carbon emissions by 39% and restores critical ecosystem functions in one year without any increase in methane emissions.  The 6-year study reintroduced water flow to a degraded freshwater wetland.  Over the course of the study, carbon stocks in the wetland increased by 53%.  Freshwater wetlands cover less than 10% of the Earth’s surface but contribute up to 25% of global methane emissions.  Despite this, they still play a crucial role in global ecosystem function.

Floodplain or riparian wetlands comprise over half of global wetlands.   They store less carbon than peatlands but restoring them gains substantial ecosystem benefits quickly.  The carbon is stored in plant roots and soil.  Wetlands are nature’s purification system removing both nitrogen from waterways and carbon from the atmosphere. 

Restoring and managing freshwater wetlands for the purpose of carbon sequestration also boosts flood and drought resilience.  Riparian wetlands are connected to other ecosystems like rivers and streams and provide benefits to them.

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Restored wetlands reap benefits for climate, drought-resilience after just one year: study

Photo, posted January 7, 2014, courtesy of Tom Barnes / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Abandoned farmland and the environment

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Abandoned farmland has been increasing dramatically in recent decades.  Estimates are that a billion acres – an area half the size of Australia – have been relinquished from cultivation globally.  While more and more of the tropics have been cultivated in recent times, the global amount of land used for agriculture has been in decline since 2001.  In the past 30 years, arable land in the United States has declined by almost a sixth.  The situation in Europe is similar.  Huge amounts of the former Soviet Union now lie abandoned. 

Farmland is abandoned for various reasons.  It may suffer from damaged soil so that crop yields are too low to be worth the effort.  Farm owners may become too old or be physically unable to continue farming.  Many younger people head for jobs in the cities and more attractive opportunities.  Wars, natural and man-made disasters, and political turmoil have all contributed.

Another form of largely ignored lands are so-called degraded forests.  These are forests that were logged in the past but are no longer productive and aren’t protected either.  These places also represent unused land with great potential value.

Ecologists point to the potential of these lands as neglected resources for rewilding efforts, improving biodiversity, and for increasing natural ways to capture carbon.  Left to its own devices, nature will usually reclaim abandoned places.  This generally provides benefits for biodiversity and climate.  But mapping, studying, managing, and protecting the increasingly vast tracts of abandoned land could increase their potential to contribute to climate change mitigation and the restoration of species and their habitats.

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Abandoned Lands: A Hidden Resource for Restoring Biodiversity

Photo, posted January 26, 2023, courtesy of Larry Syverson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The benefits of agroecology

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Agroecology focuses on sustainably managing agricultural systems by applying ecological principles.  The goal is to optimize the interactions between plants, animals, humans, and the environment.

A four-year study by the UK Centre for Ecology and Hydrology found that incorporating nature-friendly practices within farming increases biodiversity, pollination by bees, natural pest control, and the numbers of earthworms. 

The study compared three agricultural systems:  typical intensive agriculture, enhanced ecological farming, and maximized ecological farming.  Enhanced ecological farming involves planting wildflower field margins to provide habitat for bees, beetles, and spiders, and sowing overwinter cover crops to capture carbon and retain soil nutrients.  Optimized ecological farming adds planting in-field strips of wildflowers to attract beneficial insects and adding organic matter such as farmyard manure to improve soil health.

The ecological systems had increased populations of earthworms and pollinators, as well as natural predators of crop pests. 

The study concluded that while there are multiple benefits in terms of biodiversity, soil carbon, and crop yield when ecological farming systems are used, many farmers will be deterred from adopting agroecological farming practices and system because of the reduced profitability.  They argue that financial incentives such as subsidies are needed and are well worth it for the long-term sustainability of agriculture.

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Nature-friendly farming boosts biodiversity and yields but may require new subsidies 

Photo, posted July 27, 2023, courtesy of Judy Dean via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Soda can hydrogen

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Hydrogen is an ideal climate-friendly fuel because it doesn’t release carbon dioxide when it is used.  But most hydrogen is produced in ways that result in significant carbon emissions. Thus, the search for green hydrogen goes on. 

Last year, engineers at MIT developed a new process for making hydrogen that significantly reduces the carbon footprint of its production.  The recipe uses seawater and recycled soda cans. 

Pure aluminum reacts with water, breaking up the water molecules to produce aluminum oxide and pure hydrogen.  But when aluminum is exposed to oxygen, it forms a shield-like layer that prevents the reaction.

The MIT researchers found that the shield can be removed by treating aluminum with a small amount of gallium-indium alloy.  Mixing the pure aluminum with seawater not only produces hydrogen, but the salt in the seawater precipitates out the gallium-indium, making it available for reuse.

The research team carried out a “cradle-to-grave” life cycle assessment of the process, taking into account every step in using the hydrogen-production process at an industrial scale.  They found that using recycled aluminum – chopped-up soda cans – is environmentally and economically superior to using “primary” aluminum, mined from the earth. The cans would be shredded into pellet and treated with the gallium-indium alloy.  The pellets would be processed near a source of seawater where they would be combined to generate hydrogen on demand.

According to their analysis, the hydrogen produced would be at least competitive economically and environmentally with other potential methods of producing green hydrogen.

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Study shows making hydrogen with soda cans and seawater is scalable and sustainable

Photo, posted July 29, 2020, courtesy of Bruce Dupree via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Reducing emissions from ocean shipping

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Ocean shipping is a significant contributor to global carbon emissions, accounting for about 3% of the total.  It is a key part of international trade, moving goods like electronics, automobiles, and oil.  It relies on fossil fuels, and, without significant changes, shipping’s emissions could more than double by 2050.  Ocean shipping is one of the world’s most difficult to decarbonize industrial sectors.

Scientists at the University of Southern California and Caltech, collaborating with a startup company called Calcarea, have developed a shipboard system that could remove up to half of the carbon dioxide emitted by shipping vessels. The system is fairly simple and scalable.

The process mimics a natural chemical reaction that takes place in the ocean.  As a cargo ship moves through seawater, the CO2 from the ship’s exhaust is absorbed into water that is pumped onboard.  This makes the water more acidic.  The treated water is then passed through a bed of limestone, where it reacts with the rock to form bicarbonate, which is a stable compound that already exists naturally in seawater.  The treated seawater, now stripped of the carbon dioxide, is dumped back into the ocean.

Sophisticated ocean modeling examined what would happen when the bicarbonate-rich water is released back into the sea over a hypothetical 10-year period.  The model showed a negligible impact on ocean pH and chemistry.

The researchers estimate that widespread adoption of the technique could reduce shipping-related carbon dioxide emissions by 50%.  The startup company Calcarea is working to bring the technology to market and is in early discussions with commercial shippers.

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USC technology may reduce shipping emissions by half

Photo, posted November 14, 2017, courtesy of Bernard Spragg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Shrinking coal and the gas trap

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An important part of the 2015 Paris Climate Agreement is reducing the use of coal to produce electricity.  Coal is the dirtiest fuel in common use and not burning it is a way to greatly reduce emissions.  Ten years later, coal consumption around the world has decreased dramatically. 

The most convenient alternative to coal is natural gas, which is still a fossil fuel, but one that releases less carbon than coal.  As a result, around the world many countries have increasingly switched from coal to natural gas.

While the switch is a step in the right direction, it is also one that comes with an unintended consequence.  Economists at Stanford University have found that natural gas exports by countries have the effect of discouraging investments in renewable energy.  Over the long term, the result is increases in carbon emissions.  The Stanford researchers refer to this situation as ‘the gas trap’.

As a result of the gas trap, even countries that are very concerned about climate change and want to take action by abandoning the use of coal may end up reducing their investments in renewables and, ultimately, producing more emissions.

This problem comes about because replacing fossil fuels with renewables requires large investments and can take years before the renewables can fully compete with coal.  Natural gas, as a “transition fuel” gives countries time to develop renewable solutions.  But natural gas producers keep providing large amounts of their product at attractive prices so that customers buy more and more of it rather than investing in renewables.  The gas trap isn’t permanent or inevitable, but it is currently a problem.

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How the rush to quit coal is fueling a new ‘gas trap’

Photo, posted February 7, 2017, courtesy of Christian Collins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Rainforests and thunderstorms

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Tropical forests are dying at an alarming rate, and not just from deforestation. Even intact forests are losing trees, threatening biodiversity, carbon storage, and the global climate. While drought and rising temperatures are often blamed, new research points to a surprising culprit: thunderstorms.

These intense, short-lived convective storms, common in the tropics, are increasing due to climate change. With strong winds and lightning, they can snap trees, strip canopies, and kill even the most robust tree specimens.

In a perspective paper recently published in the journal Ecology Letters, a research team led by the Cary Institute of Ecosystem Studies argues that thunderstorms, often overlooked in carbon storage research, may be the leading cause of tree death in tropical forests. The research team estimates that storms have caused 30 to 60% of tree mortality in the past, a number that is likely rising as storm activity increases 5 to 25% each decade.

Including storm data in forest carbon studies changes the picture significantly. Earlier models showed that carbon levels dropped sharply when temperatures rose beyond a certain point. But when storm impacts were added, that pattern disappeared, suggesting that storms – not just heat – may be a key factor in carbon loss.

Understanding which species are most vulnerable is critical for reforestation and conservation efforts. Mature trees store the most carbon, so if they’re lost to storms, future forests may fall short of their carbon storage potential.

As storm activity increases each decade, the stakes grow higher.  Accounting for storms could reshape how we protect, restore, and plan for the future of our forests. 

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Are the Amazon’s biggest trees dying? Forest coroners investigate

Photo, posted July 2, 2017, courtesy of Anna & Michal via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Forest-based agroforestry

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Tree plantings have become a go-to climate solution for governments and conservation groups due to the carbon-storing potential of trees.  While planting new trees on open farmland would help capture additional carbon, a new study led by scientists from Yale School of the Environment suggests a powerful alternative: forest-based agroforestry.

Instead of clearing land for crops or starting fresh with new trees, forest-based agroforestry (or FAF) brings agriculture into existing forests.  Think fruits, nuts, and medicinal plants, for example, grown sustainably under a forest canopy – all while maintaining biodiversity and storing carbon.

According to the researchers, human activity in forests is often seen as harmful. But for thousands of years, Indigenous and local communities have managed forests in ways that actually strengthen them.

The study, which was recently published in the journal Nature Climate Change, found that FAF not only rivals tree planting in terms of climate benefits, but it can also generate income and support cultural practices tied to the land.

Despite these benefits, forest-based agroforestry receives far less funding and policy support due to two key misconceptions. It’s frequently confused with industrial systems focused on global commodity crops, and results from tropical regions are wrongly assumed to apply to temperate and boreal forests.

The researchers recommend including FAF in agroforestry policies, clearly distinguishing it from harmful industrial practices, and expanding research on FAF in temperate and boreal regions to guide better land management.

Forest-based agroforestry appears to be a natural climate solution hiding in plain sight.

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Agriculture in Forests Can Provide Climate and Economic Dividends

Photo, posted May 8, 2023, courtesy of Preston Keres / USDA Forest Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Deconstructing buildings

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An estimated 30 million tons of wood waste from construction and demolition in the U.S. ends up in landfills each year.  A growing number of cities have launched initiatives to reuse the wood instead.  It is a strategy to reduce carbon emissions, cut waste, and shift towards a circular economy.

For a long time, salvaged wood was a niche pursuit by people who valued the fine grain and enduring quality of older wood.  Reclaimed old-growth lumber offers character and strength.  These people pursued construction that uses wood with a story – timber recovered from historic structures, collapsing barns, and other demolished buildings.

Now, there are multiple companies in the business of salvaging wood from buildings.  Cities and businesses are embracing the use of reclaimed materials.   Ordinances in cities like Portland, Oregon, Boulder, Colorado, and San Antonio, Texas require older buildings to be taken apart for repurposing their materials.  Palo Alto, California has banned demolition completely. 

Portland was the first U.S. city to require old residential homes to be deconstructed.  After a decade, contractors have deconstructed more than 650 homes in the city, salvaging 2,000 tons of reusable wood.

Using reclaimed wood in local buildings stores carbon and reduces emissions by avoiding the need to cut new trees, process materials, and ship them long distances.

Deconstructing buildings is not a widely available skill.  Contractors have to be trained on how to dismantle buildings piece by piece.  But there is now a national registry of deconstruction trainers and a network of practitioners.

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Deconstructing Buildings: The Quest for New Life for Old Wood

Photo, posted May 16, 2018, courtesy of Alexandre Prevot via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Planting trees to cool the planet

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Planting lots of trees is one of many strategies being pursued to combat climate change. Forests absorb carbon dioxide, provide shade, and help regulate temperatures. They also support biodiversity and improve air and water quality.

According to a new study by researchers from the University of California – Riverside, restoring forests to their pre-industrial extent could reduce global average temperatures by 0.34 degrees Celsius. That’s equivalent to about 25% of the warming the Earth has already experienced.

The study models restoring 4.6 million square miles of forest.  While previous studies have focused on the role trees play in removing carbon, this research adds that trees also alter atmospheric chemistry in ways that boost their cooling impact.

Trees release natural chemicals called BVOCs – biogenic volatile organic compounds – which interact in the atmosphere to form particles that reflect sunlight and promote cloud formation. These effects enhance the cooling impact of forests, especially in climate models that take these chemical reactions into account.

But not all reforestation is created equal. The benefits of reforestation vary by region, with tropical forests offering stronger cooling and fewer drawbacks.  Importantly, the researchers emphasize that meaningful climate benefits don’t require restoring every lost forest. Small, localized efforts can still shift regional climates.

While forest restoration can meaningfully aid climate efforts, the researchers stress that it must complement – not replace – fossil fuel reductions.

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Does planting trees really help cool the planet?

Photo, posted May 20, 2005, courtesy of Ben Britten via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

More trouble from sea urchins

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Sea Urchins are real troublemakers.  On the West Coast, the sea urchin population exploded when the sunflower sea stars that eat them were decimated by a wasting disease.  Urchins devour kelp and they ate up 96% of the region’s kelp forests.  Kelp forests serve as shelter and food for a vast array of marine life and kelp sequesters as much as 20 times more carbon than terrestrial forests.

A new study by researchers at North Carolina State University looked at the health of the coral reef in Honaunau Bay on Hawaii’s Big Island and found that ballooning sea urchin populations are endangering the survival of the reef.

Fishing in these areas has greatly reduced the numbers of fish that feed on sea urchins and urchin populations have grown significantly.   There are areas of the reef where there are 51 sea urchins in every square meter.

The reef is already not growing at a healthy rate as a result of water pollution and overheating created by climate change.  These result in a poor environment for coral to reproduce and grow, which leaves the reef unable to keep up with the pace of erosion caused by urchins.

Reef growth is measured in terms of net carbonate production – namely the amount of calcium carbonate produced over time.  In the 1980s, healthy reefs in Hawaii produced about 15 kilograms of carbonate a year per square meter.  The Honaunau Reef today shows an average net carbonate production of only 0.5 kilograms per square meter.  The reef is growing very slowly and can’t keep up with urchin erosion.

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Huge sea-urchin populations are overwhelming Hawaii’s coral reefs

Photo, posted October 29, 2017, courtesy of Rickard Zerpe via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Record forest loss

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The world lost a record amount of forests last year.  The biggest factor for the unprecedented losses were wildfires that raged around the world.

According to the annual update by the University of Maryland and the World Resources Institute, pristine rainforests alone lost 17 million acres, which was nearly twice as much as in the previous year.  Overall, the world lost the equivalent of 18 soccer fields of forested land every minute last year.

Over time, agriculture has been the primary cause of forest losses, but last year, for the first time since record-keeping began, fires were the leading cause, accounting for nearly half of all the destruction.

With respect to the climate, wildfires emitted over 4 billion tons of greenhouse gasses, which is more than four times the amount generated by air travel in 2023.

Land clearing for agriculture, cattle farming, and other purposes was by no means in decline last year.  In fact, it rose by 14%, which was the sharpest increase in almost a decade.  This trend could permanently transform critical natural areas, unleashing large amounts of carbon, intensifying climate change, and fueling even more extreme fires.

Forests are a major contributor to the natural storing of carbon dioxide.  Intact tropical forests are especially effective at storing carbon.

Brazil has the largest area of tropical forest and it accounted for 42% of all tropical primary forest loss in 2024.  Fires fueled by the worst drought on record caused two thirds of that loss, more than a sixfold increase over the previous year.

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Global Forest Loss Hit a Record Last Year as Fires Raged

Photo, posted September 12, 2024, courtesy of the USDA Forest Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Restoring oil well sites with moss

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Researchers at the University of Waterloo in Canada have developed a method for restoring peatlands at tens of thousands of oil and gas exploration sites in Western Canada. 

A well pad is a prepared area used for drilling oil or gas wells, encompassing the site where drilling equipment, wellheads, and related facilities are located.  Preparing well pads involves burying native peatland vegetation under clay or sand, thereby eliminating the ability of the peatland to sequester carbon as well reducing available habitat for wildlife.

Restoring well sites has typically involved planting trees or grasses to eventually establish forests or grasslands.  The Waterloo method returns a well pad to its condition before drilling occurred and is part of ongoing efforts to restore peatlands, which are known to be even more effective for sequestering carbon than tropical forests.

The Waterloo technique involves lowering the surface of a decommissioned well site and transplanting native mosses onto it to effectively recreate a peatland.    They tested the technique to scale at an entire well pad and found that it results in sufficient water for the growth of peatland moss across large portions of the study site.

The results suggest that re-establishment of peatland vegetation on lowered well pads is possible.  The researchers plan to continue monitoring the ecosystem in the study’s well pads to confirm that the transplanted mosses will be self-sustaining over the coming decades.  They will focus on increasing the amount of water that flows from surrounding natural peatlands into the converted well pads to further optimize soil moisture. 

This work could represent an important milestone in ecological restoration.

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Restoring oil wells back to nature with moss

Photo, posted November 6, 2014, courtesy of Chris Boyer / Kestrel Aerial Services via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Nature: An important climate ally

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Nature is often seen as a victim of climate change, but it’s also one of the most powerful tools we have to fight it. Natural ecosystems, such as forests, wetlands, grasslands, oceans, and soils, absorb and store massive amounts of carbon dioxide. These ecosystems not only help reduce the concentration of greenhouse gases in the atmosphere, but they also regulate temperatures and provide buffers against extreme weather.

One of the most effective strategies for mitigating climate change is simply protecting and restoring these natural areas. For example, mangrove forests – those coastal wetlands filled with tangled, salt-tolerant trees – sequester carbon at high rates and help protect coastal communities from storm surges and rising seas.  Peatlands – another type of wetland – store more carbon than all the world’s forests combined – despite only covering 3% of Earth’s land surface.  Global restoration efforts are underway, from replanting mangroves in Southeast Asia to rewetting degraded peatlands in Europe.

Creating urban green spaces like parks and community gardens, restoring forests through native tree plantings, and adopting sustainable agricultural practices like cover cropping and agroforestry are all proven to be low-cost, high-impact climate solutions. 

While nature-based solutions are gaining recognition, they remain critically underfunded, according to a recent United Nations report.  Closing this gap is essential to unlocking nature’s  full climate potential.

Investing in nature isn’t just about preserving Earth’s natural beauty.  It’s a practical strategy for building a more resilient and sustainable future.

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Mangrove forests and rising seas

Financing Nature-based Solutions for a better future

Finding peatlands

The Importance Of Urban Green Spaces

Photo, posted October 23, 2011, courtesy of the Everglades National Park / NPS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

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

Redefining the perfect beach

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The iconic image of the “perfect” tropical beach is fine white sand, a few coconut palm trees, a gently sloping beach, and unobstructed views of the blue sea.  This image came about to a great extent from fascination with Polynesian scenery at the time of World War II.   And because of this imagery, beach resorts around the world have tried to achieve this look, often by reengineering and altering natural ecosystems to meet this artificial standard of perfection.

But natural tropical and subtropical beaches with their mangrove forests and seagrass meadows are complex ecosystems that support biodiversity, provide protection from storms, and capture carbon in significant amounts from the atmosphere.

With all this relandscaping of beaches, by the end of the 20th century, 35% of the world’s mangrove forests and 29% of its seagrasses were gone.  Mangroves sequester 10 times more carbon than mature tropical forests and sea grass can pull in up to 15 times as much.

In recent years, some resort developers are starting to embrace having beachscapes in their more natural states.  They are planting or preserving native vegetation and allowing sea grass to flourish.  The Six Senses Laamu resort in the Maldives, a major luxury tourist destination, was a trendsetter in this way. 

Coconut palms do little to prevent sand erosion, block wind, or even provide much shade.  In a warming world with increasingly powerful storms, they offer little protection for the world’s beaches.  They are not even native to the Caribbean, where they are now ubiquitous, having been introduced by Europeans.

Many resort developers are now rethinking the description of the perfect beach.

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Your Resort’s ‘Perfect’ Beach Is a Lie

Photo, posted March 2, 2011, courtesy of Breezy Baldwin 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

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

Thawing permafrost in the Arctic

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Permafrost covers about a quarter of the landmass in the Northern Hemisphere.  It stores vast quantities of organic carbon in the form of dead plant matter.  As long as it stays frozen, it is no threat to the climate.  But as permafrost thaws, microorganisms start breaking down that plant matter and large amounts of carbon are released into the atmosphere in the form of carbon dioxide and methane.

Scientists estimate that there could be two and a half times as much carbon trapped in Arctic permafrost as there is in the atmosphere today.

Thawing permafrost poses various risks to the Arctic environment and the livelihoods of its people.  According to a new study led by researchers from the University of Vienna in Austria, Umeå University in Sweden, and the Technical University of Denmark, thawing permafrost threatens the way of life of up to three million people.

To identify these risks, the research team studied four Arctic regions in Norway, Greenland, Canada, and Russia between 2017 and 2023.  The research, which was recently published in the journal Communications Earth and Environment, identified five key hazards posed by the thawing permafrost: infrastructure failure, disruption of mobility and supply, decreased water quality, challenges for food security, and exposure to diseases and contaminants.

These are present developments – not future dangers.  Global scientific cooperation, policy interventions, and investment in research are critical to mitigate the impact of thawing permafrost and address the broader consequences it brings.

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A transdisciplinary, comparative analysis reveals key risks from Arctic permafrost thaw

Thawing permafrost threatens up to three million people in Arctic regions

Photo, posted February 9, 2017, courtesy of Benjamin Jones / USGS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Storing carbon in buildings

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According to a new study by researchers at the University of California, Davis and Stanford University, construction materials used in buildings have the potential to lock away billions of tons of carbon dioxide.  The study, published in Science, shows that storing CO2 in buildings could be a major contributor to efforts to reduce greenhouse gas emissions.

Overall efforts in carbon sequestration take carbon dioxide – either as it’s being produced or once it’s already in the atmosphere – and store it away.  Storing it might involve injecting it into underground caverns or deep in the ocean.  Alternatively, storing it might involve converting it into a stable form using chemical reactions.  These various strategies involve both practical challenges and potential environmental risks.

The new study suggests that many materials that are already produced in large quantities have the potential to store carbon dioxide.  These include concrete, asphalt, plastics, wood, and brick.  More than 30 billion tons of these materials are produced worldwide every year.

Ways to accomplish carbon storage include adding biochar into concrete, using artificial rocks loaded with carbon as concrete and asphalt aggregates, plastic and asphalt binders based on biomass instead of petroleum, and including biomass fiber into bricks. 

The largest potential is using carbonated aggregates to make concrete.  Concrete is by far the world’s most popular building material with more than 20 billion tons being produced each year.

The feedstocks for these ways to store carbon in building materials are mostly low-value waste materials, so the economics of implementing these carbon sequestering strategies are likely to be quite favorable.

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Storing Carbon in Buildings Could Help Address Climate Change

Photo, posted October 19, 2022, courtesy of Alexandre Prevot 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...)