rocks

Turning Carbon Into Stone | Earth Wise

January 31, 2023 By EarthWise Leave a Comment

A start-up company in Oman called 44.01 was recently awarded a $1.2 million Earthshot Prize by Prince William of the U.K. The company, whose name corresponds to the molecular weight of carbon dioxide, is working on speeding up natural chemical reactions that take carbon from the air and lock it into solid mineral form.

The company’s location in Oman is no random occurrence. The mountains of northern Oman and along the coast of the United Arab Emirates are the site of a huge block of oceanic crust and upper mantle that was thrust upward some 96 million years ago. The tilted mass of rock is over 200 miles long and is the largest surface exposure of the Earth’s mantle in the world.

This type of rock, called peridotite, is rich in olivine and pyroxene, which react with water and carbon dioxide to form calcium-based minerals like serpentine and calcite that permanently lock in carbon. Other kinds of rock also are capable of carbon-storing mineralization, but this mantle rock is the most effective for the purpose. It only exists at the Earth’s surface in a few places, including Papua New Guinea and some spots in California and Oregon.

The 44.1 company is planning to use solar-powered direct air capture devices to remove CO₂ from the air, use it to produce carbonated water, and inject the water into the reactive rocks. The company will operate a couple of pilot systems during 2023. Ultimately, the company believes it can scale up the process to be able to permanently sequester as much as a billion tons of CO₂ a year by the year 2040 without needing to inject the gas into deep caverns or find other places to store it.

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With Major Prize, a Project to Turn Carbon Emissions to Stone Gains Momentum

Photo, posted August 10, 2018, courtesy of JM McBeth via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

How Quickly Can The Planet Recover? | Earth Wise

December 6, 2021 By EarthWise Leave a Comment

Climate change refers to long-term shifts in temperatures and weather patterns. Historically, these shifts were natural. But since the Industrial Revolution, scientists have found that the main driver of climate change has been human activities, primarily by adding significant amounts of greenhouse gases into the atmosphere through the burning of fossil fuels.

Today, climate change is destabilizing Earth’s temperature equilibrium and is having a widespread impact on humans, animals, and the environment. Some of the consequences of anthropogenic climate change include warmer air and ocean temperatures, shrinking glaciers, increasing spread of pests and pathogens, declining biodiversity, and more intense and frequent extreme weather events.

But how quickly can the climate recover from the warming caused by an increase in carbon dioxide in the atmosphere?

Researchers from Johannes Gutenberg-University Mainz in Germany looked into this question by investigating the significant rise in global temperatures that took place 56 million years ago. Likely triggered by a volcanic eruption, the increase of between 5 and 8 degrees Celsius was the fastest natural period of global warming that has impacted the climate.

Because higher temperatures cause rocks to weather faster, the research team decided to analyze the weathering processes that occurred during the warming event 56 million years ago. Their findings, which were recently published in the Journal Science Advances, indicate that the climate took between 20,000 and 50,000 years to stabilize following the rise in global temperatures.

Climate change is not some distant problem. It is happening now and it poses a serious threat to all forms of life. We need to address the problem with more urgency.

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How quickly does the climate recover?

Photo, posted August 27, 2017, courtesy of Lt. Zachary West (100th MPAD) / Texas Military Department via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Metals In Western Water Supplies | Earth Wise

October 29, 2021 By EarthWise Leave a Comment

A new study published by the University of Colorado Boulder looked at the problem of rivers being contaminated by acid rock drainage. Rocks that include sulfide-based minerals, such as pyrite, oxidize when exposed to air and water. The resulting chemical reaction produces sulfuric acid which, when present in water, dissolves metals like lead, cadmium, and zinc. The recent study found that rare earth elements are also leached out of rock by this process.

Rock drainage occurs naturally throughout the western United States, but historic mines that disturbed large amounts of rocks and soil have dramatically increased this process and have led to growing downstream water pollution. Upwards of forty percent of the headwaters of major rivers in the West are contaminated by some form of acid mine or rock drainage.

The warming climate has brought longer summers and less snow in winters. Longer, lower stream flows make it easier for metals to leach into watersheds and concentrate the metals that would otherwise be diluted by snowmelt.

Rare earth elements are essential components of many high-tech devices such as computers, hard drives, and cell phones. There is not a long history of studying the hazards they might represent when they enter the environment.

The study looked at the Snake River watershed in Colorado and found that increasing amounts of rare earth elements are entering Colorado water supplies. Concentrations of rare earth elements are not ordinarily monitored and there are no water quality standards set for them.

According to the researchers, once rare earth elements get into water, they tend to stay there. Traditional treatment processes don’t remove them. It is a growing problem that needs to be addressed.

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Rare earth elements and old mines spell trouble for Western water supplies

Photo, posted October 27, 2007, courtesy of Dion Gillard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climbing To Escape The Heat | Earth Wise

March 18, 2021 By EarthWise Leave a Comment

Colorado has warmed by nearly 3.5 degrees Fahrenheit since the 1980s because of human-caused climate change. As a result, many mammal species have shifted uphill to escape the heat.

The golden-mantled ground squirrel is a popular sight among tourists in the Rocky Mountains. It is one of the most photographed animals there as they pose on rocks near roadsides and in campgrounds. According to University of Colorado research recently published in the journal Ecology, these squirrels have shifted their range upward by 659 feet. The new study looked at the ground squirrels along with 46 other small mammals. On average, these animals have shifted their range upward by more than 400 feet since the 1980s.

The researchers visited multiple sites in Colorado’s Front Range and San Juan mountains over the course of several years to collect records of the current ranges of these 47 animals. They then compared the findings from their surveys to over 4,000 historic records from collections dating back to the 1980s.

The researchers expected to see some changes, but not of the magnitude they observed. For example, before 1980, the pygmy shrew was never detected above about 9,800 feet in elevation. Today, its maximum extent is more than 11,800 feet.

Montane mammals – which are those who already live at higher elevations – have moved up an additional 1,100 feet on average. If this trend continues, some animals and even entire communities may be pushed to the tops of mountains with nowhere else to go. According to the researchers, the study paints a stark picture of a mountain range in crisis.

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Small mammals climb higher to flee warming temperatures in the Rockies

Photo, posted September 6, 2002, courtesy of Franco Folini via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Living On Trash | Earth Wise

March 16, 2021 By EarthWise Leave a Comment

Litter is persistent and widespread in rivers worldwide. The world’s major rivers and estuaries are hotspots for plastic waste. Trash and microparticles wash down tributaries and build up before rivers enter oceans.

New research published in the journal Freshwater Biology has found that as this waste accumulates, aquatic river species like insects and snails are increasingly choosing to settle on plastic rather than on natural features like rocks and fallen branches.

Researchers from the University of Nottingham in the UK collected plastic waste from three rivers in eastern Britain along with rocks from the same rivers. Their analysis of all the macroinvertebrates on the items’ surfaces found that the surfaces of plastic waste items had nearly four times the diversity of the small animals as did the rocks. In addition, the more complex the plastic’s surface was, the higher the diversity.

The growing abundance of plastic waste coincides with a decline in natural habitat features in urban rivers. This is a result of increasing amounts of sedimentation from development that blankets riverbeds in silt and sand, restricting the supply and movement of rocks, fallen tree branches, and aquatic plants.

Clearly litter can serve as a place for various species to colonize, but trash is not a good environment for them. Trash can release toxic chemicals and entangle animals. Microplastics pose risks for the animals if ingested.

Estimates are that between 1.15 and 2.41 million tons of plastic waste enter the ocean every year from rivers around the world. Natural habitats have become rare in urban rivers. River ecosystems built around piles of trash are not a good thing.

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As Plastic Pollution in Rivers Gets Worse, Species Are Increasingly Living on Litter

Photo, posted August 17, 2010, courtesy of Renee_McGurk via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Artificial Aquatic Polyps | Earth Wise

September 16, 2020 By EarthWise Leave a Comment

Corals are often mistaken for rocks because of their hardened surfaces. And, since they attach or “take root” to the sea floor, they are often mistaken for plants. But unlike rocks, corals are alive. And unlike plants, corals do not make their own food. Corals are actually animals.

Most of these structures that we call “coral” are made up of hundreds to thousands of tiny coral creatures called polyps. A coral polyp, which is often no thicker than a nickel, has a saclike body and mouth that is encircled by stinging tentacles. Polyps are responsible for a host of ecosystem services, including nourishing corals, and aiding coral survival by generating self-made currents through the motion of their soft bodies.

Inspired by these marine organisms, researchers from the University of Warwick in the UK and Eindhoven University of Technology in the Netherlands have collaborated to develop an artificial aquatic polyp capable of removing contaminants from water. The 1 square centimeter wireless robot polyp can attract, grasp, and release objects, moving under the influence of a magnetic field and whose “tentacles” are triggered by light.

The next step for the researchers is to see if the technology can be successfully scaled up from laboratory to pilot scale. In order for that to happen, the team has to design an array of artificial polyps capable of working harmoniously together.

Corals are an incredibly important part of ocean ecosystems. And while it remains to be seen how much value artificial polyps can achieve in future applications, it serves as another example of scientists emulating nature to create more sustainable designs.

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Aquatic robots can remove contaminant particles from water

An artificial aquatic polyp that wirelessly attracts, grasps, and releases objects

Photo, posted April 14, 2011, courtesy of Derek Keats via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Ocean Acidification And Mass Extinction

November 26, 2019 By EarthWise Leave a Comment

Since the industrial revolution, the concentration of carbon dioxide in the atmosphere has increased due to the burning of fossil fuels and land use changes. The ocean absorbs about 30% of the CO2 that is released in the atmosphere. As the levels of atmospheric CO2 increase, so do the levels in the ocean.

When CO2 is absorbed by the ocean, a series of chemical reactions occur, resulting in seawater becoming more acidic. Ocean acidification threatens calcifying organisms, such as clams and corals, as well as other marine animals, like fish. When these organisms are at risk, the entire marine ecosystem may also be at risk.

In fact, according to research recently published in the journal Proceedings of the National Academy of Sciences, fossil evidence from 66 million years ago has revealed that ocean acidification can cause the mass extinction of marine life. Researchers analyzed seashells in sediment laid down shortly after a giant meteorite hit earth. This strike wiped out the dinosaurs and 75% of marine species. Chemical analysis of the shells revealed a sharp drop in the PH of the ocean over hundreds of years after the meteorite strike. The meteorite impact vaporized rocks, causing carbonic acid and sulphuric acid to rain down, acidifying the ocean. The strike also resulted in mass die-off of plants on land, increasing atmospheric CO2.

Researchers found that the pH dropped by 0.25 pH units in the 100 to 1,000 years after the meteorite strike. Alarmingly, scientists expect the pH of the ocean to drop by 0.4 pH units by 2100 if our carbon emissions continue as projected.

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Ocean acidification can cause mass extinctions, fossils reveal

Photo, posted March 16, 2017, courtesy of Zachary Martin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Growing Rocks To Store Carbon

April 24, 2019 By EarthWise Leave a Comment

The US Geological Survey recently published a comprehensive review of geological carbon storage in sedimentary rocks through carbon mineralization. That is the process by which carbon dioxide becomes a solid mineral, such as a form of carbonate. Certain rocks undergo a chemical reaction when exposed to carbon dioxide and turn into different minerals as a result.

The idea is to use carbon mineralization as a way to permanently store carbon dioxide that has been captured from power plant emissions, other industrial activities, or even directly from the atmosphere.

Two basic approaches are injecting the CO2 deep underground or exposing it to crushed rocks at the surface. The two types of rock best suited for mineralization through injection are basalt and various ultramafic rocks. Pilot studies have shown that injection into basalt can lead to mineralization in under two years.

Exposing carbon dioxide to crushed rock at the surface generally makes use of crushed mining waste. Mineralization can be much faster in this case because there is more surface area on the crushed rock where mineralization occurs. (However, the quantities of rock available at the surface are much less than what exists deep underground).

Like all carbon capture and storage approaches, the key consideration is cost. The USGS study estimates that underground injection would cost around $30 per metric ton of CO2. The crushed rock approach might only cost $8 per metric ton, but that assumes the crushed rock is already available. If it must be newly mined, the costs would obviously go up significantly. To put this into perspective, a typical car produces around 4 metric tons of CO2₂ per year. So, it would cost somewhere between $30 and $120 a year to eliminate the emissions from one car. Perhaps that is a price we need to pay until we ditch gasoline cars.

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