volcanoes

Tracking atmospheric mercury

May 13, 2025 By EarthWise Leave a Comment

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

Mining extinct volcanoes

December 2, 2024 By EarthWise Leave a Comment

Rare earth elements are a group of 17 elements that are used to improve the performance, efficiency, and durability of a wide range of products. More than 200 products across a diverse set of applications make use of rare earth elements. Although the amount of rare earth used in a particular product may not be very much of its weight, volume, or monetary value, it may often be necessary for the device even to function. Rare earth elements react with other elements to form compounds that are essential because of their specific chemical behaviors.

Rare earth elements are not actually rare; in fact, they are fairly common. But they are mostly not found in their pure form and are generally difficult to refine. China accounts for more than 90% of global production of rare earth elements and this represents a strategic problem for the rest of the world.

New research by scientists from the Australian National University has found that some extinct volcanoes, which have not erupted for thousands or even millions of years, may be rich sources of rare earth elements. Furthermore, those elements may be easier to extract than the ones from other sources because the iron-rich magma that formed the volcanoes could be up to 100 times more efficient at concentrating rare-earths than magma found in active volcanoes today.

The clean tech industry uses rare earths for wind turbines, solar panels, and electric cars. The demand for rare earths may grow fivefold by the end of this decade. Relying on just one country for the world’s supply is a major concern. There are ancient volcanoes all over the planet and they may represent a solution to a global problem.

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Extinct Volcanoes Could Be Source of Key Metals Needed for Clean Tech

Photo, posted June 6, 2020, courtesy of Dennis Jarvis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Extreme geothermal power

November 25, 2024 By EarthWise Leave a Comment

Krafla is one of the most explosive volcanoes in Iceland, which is home to many active volcanoes, including one recently in the news near Reykjavik that hadn’t erupted for 800 years . Krafla is the site of the Krafla Magma Testbed, which may end up being for geoscientists what the Large Hadron Collider has been for particle physicists.

For over a decade, researchers have been drilling straight into the ground at Krafla to study what goes on deep beneath an active volcano. Ten years ago, they encountered an unexpected magma chamber a little over a mile down. Their equipment was destroyed but the researchers decided that they had uncovered a unique opportunity to study magma dynamics and potentially be able to tap into a significant new energy source.

The plan is to use the tremendous heat energy contained in magma to dramatically improve the production of geothermal energy. Krafla is already the site of a geothermal energy plant that makes use of the heat beneath the surface to boil water that then drives turbines to generate electricity.

Forthcoming drilling projects will make use of new equipment that can handle the harsh conditions that will be encountered in the magma chamber. The goal is to tap directly into the magma to produce superheated steam that could produce ten times more power than conventional geothermal systems. Conventional systems access temperatures around 200 to 300 degrees; the magma is at 1,800 degrees.

It will take a few years to complete the project, but if it is successful, it could have implications well beyond Iceland. There are many active volcanoes all over the world.

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Drilling into magma: Risky plan takes geothermal to supercritical extremes

Photo courtesy of Landsvirkjun.

Earth Wise is a production of WAMC Northeast Public Radio

Side Effects Of Geoengineering | Earth Wise

July 20, 2020 By EarthWise Leave a Comment

As the world struggles to reduce the greenhouse gas emissions that are warming the global climate, some researchers are exploring proposals to deliberately engineer climate changes to counteract the warming trend. One of the most widely discussed approaches is to shade the Earth from a portion of the sun’s heat by injecting the stratosphere with reflective aerosol particles. Proponents of this idea point out that volcanoes do essentially the same thing, although generally for only a limited amount of time. Particularly large eruptions, such as the Krakatowa eruption of 1883, wreaked havoc with weather around the world for an entire year.

Schemes to launch reflective aerosols – using planes, balloons, and even blimps – appear to be quite feasible from the standpoint of physically accomplishing them. But this says nothing about the political, ethical, and societal issues involved. The point is that such an approach could indeed lower global temperatures and thereby potentially offset the warming effects of greenhouse gases.

A study by scientists at MIT looked at what other effects such a solar geoengineering project might have on the climate. Their modeling concluded that it would significantly change storm tracks in the middle and high latitudes. These tracks give rise to cyclones, hurricanes, and many more ordinary weather phenomena.

According to the study, the northern hemisphere would have weakened storm tracks, leading to less powerful winter storms, but also stagnant conditions in summer and less wind to clear away air pollution. In the southern hemisphere, there would be more powerful storm tracks.

Aside from turning the world’s weather patterns inside out, solar geoengineering would do nothing to address the serious issue of ocean acidification caused by increasing carbon dioxide levels.

As many have pointed out, playing the geoengineering game would have many unintended consequences.

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Study: Reflecting sunlight to cool the planet will cause other global changes

Photo courtesy of MIT.

Earth Wise is a production of WAMC Northeast Public Radio.

The Lockdown Cleans Up Indian Air | Earth Wise

May 13, 2020 By EarthWise Leave a Comment

Our stories often discuss how human activities change the natural environment. With most of us confined to our homes, the lack of human activities is having profound effects on the environment. We are talking about some of these this week.

India suffers from some of the worst air pollution in the world. Of the most polluted cities in the world, 21 out of 30 were in India in 2019. According to World Health Organization standards, at least 140 million people in India breathe air containing 10 times or more greater levels than the safe limit for pollutants. Air pollution contributes to the premature death of 2 million Indians every year.

Half of India’s air pollution comes from industry, 27% from vehicles, and 17% from crop burning. Crop burning is prevalent because it is much cheaper than mechanical tilling after the harvest.

On March 25, the Indian government placed its 1.3 billion citizens under a strict lockdown to reduce the spread of COVID-19. The country-wide mandate decreased activity at factories and drastically reduced car, bus, truck, and airplane traffic.

Within one week, NASA satellite sensor observed aerosol levels at a 20-year low for this time of year in northern India. Aerosols are tiny solid and liquid particles suspended in the air that reduce visibility and can damage the human lungs and heart. Some aerosols have natural sources, such as dust storms, volcanic eruptions, and forest fires. But many come from human activities such as the burning of fossil fuels and croplands. Scientists expected to see changes in atmospheric conditions during the Indian lockdown, but the current changes are dramatic. They also present a unique opportunity to separate how natural and human sources of aerosols affect the atmosphere.

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Airborne Particle Levels Plummet in Northern India

Photo, posted April 29, 2020, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Geoengineering And Volcanoes

November 14, 2019 By EarthWise Leave a Comment

Solar geoengineering is a theoretical strategy for curbing the effects of climate change by introducing aerosol particles in the upper atmosphere to reflect some of the Sun’s radiation back into space and thereby cool the planet. It would basically be intentionally tinkering with the climate system on a global scale.

The concept is fraught with the danger of unintended consequences and most experts consider the idea almost unthinkable. But there are those who see it as a last resort if all our other efforts to mitigate the effects of climate change are unsuccessful.

Proponents of the idea like to describe the technique as being like a human-made volcano. Major volcanic eruptions spew ash particles into the atmosphere which can linger for as long as a few years. The result is cooler temperatures, sometimes across much of the globe. The Krakatoa eruption of 1883 lowered average Northern Hemisphere temperatures by more than 2 degrees and created chaotic weather patterns until about 1888.

Researchers at the Carnegie Institution and two Chinese research institutions used sophisticated modeling techniques to compare the effects on the climate of a volcanic eruption with long-term geoengineering deployment.

They found that the volcanic eruption created a greater temperature difference between the land and sea than the geoengineering and resulted in very different precipitation scenarios. In both cases, there would be less available water for people on land.

Overall, the study demonstrated that volcanic eruptions are imperfect analogs for geoengineering and that scientists should be very cautious about extrapolating too much from them. It is important to evaluate geoengineering from an informed position, but the truth is that it represents a great and perilous unknown.

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Geoengineering Versus A Volcano

Photo, posted November 1, 2002, courtesy of the NASA Goddard Space Flight Center via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change Is Not Natural

July 5, 2019 By EarthWise Leave a Comment

It has been the overwhelming consensus of the scientific community for a long time that human activity and other external factors are responsible for the continuing rise in global temperature. Despite this widespread agreement, there have been those who argue that natural ocean cycles might be influencing global warming over the course of multiple decades.

A new study, published in the Journal of Climate, provides an answer to the question of how much influence natural cycles might have, and that answer is very little to none.

The study looked at observed ocean and land temperature data since 1850 and, apart from human-induced factors such as greenhouse gas concentrations, took into account other occurrences such as volcanic eruptions, solar activity, and air pollution peaks. The findings demonstrated that slow-acting ocean cycles do not explain the long-term changes in global temperatures.

Based on the study, the researchers can state with confidence that human factors like greenhouse gas emissions and particulate pollution, along with year-to-year changes caused by natural phenomena like volcanic eruptions or El Niño, are sufficient to explain virtually all the long-term changes in temperature. The idea that the oceans could have been driving the climate either in a colder or warmer direction for multiple decades in the past and therefore will do so in the future is unlikely to be correct.

A number of previous studies have compared flawed observations with flawed modeling results to claim that naturally-occurring ocean cycles have played a large role in global temperatures. The new study shows that such cycles have little influence on the climate. Reducing greenhouse gas emissions is really what we need to do.

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Global temperature change attributable to external factors, confirms new study

Photo, posted November 13, 2007, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Listening To Volcanoes

April 2, 2018 By EarthWise Leave a Comment

Volcanoes are complicated, and we don’t have universally applicable ways to predict when they might erupt. Measurements of seismicity, gas emissions and ground deformation are all useful in trying to figure out what volcanoes are up to. However, it is unlikely that will ever have definitive prediction techniques.

The Zombieless Apocalypse

November 29, 2016 By WAMC WEB

Post-apocalyptic fiction is all the rage these days. There are numerous stories featuring an endless list of civilization-ending disasters: asteroid collisions, cataclysmic earthquakes, nuclear wars, supervolcanoes, pandemics… the list goes on and on. Most of the time, humanity either perishes entirely, is reduced to a handful of heroic and astonishingly resourceful souls, or ends up inexplicably as zombies staggering around the landscape in search of brains.