natural sources

Hidden hydrogen

July 15, 2025 By EarthWise Leave a Comment

The idea of using hydrogen as a fuel or an energy source has been around for a long time. Hydrogen is the most common element in the universe, but most of it is locked up in various chemical compounds, such as water. Hydrogen is a clean fuel; burning it or using it to generate electricity in a fuel cell produces no greenhouse gas emissions. But more than 99% of the hydrogen that people current produce is obtained by methods that result in greenhouse gas emissions.

A new study by scientists at the University of Oxford, the University of Durham in the UK, and the University of Toronto looks at geological environments in which naturally occurring hydrogen could be hiding. According to the study, over the last billion years, the Earth’s continental crust is likely to have produced enough hydrogen to satisfy the energy needs of modern society for 170,000 years.

Much of that hydrogen is likely to have been lost or is inaccessible; most of it is not economically feasible to extract. But even the relatively small amount of hydrogen left could provide thousands of years of energy for us. We just have to be able to find it.

The researchers have developed what they call an “exploration recipe” which identifies where natural hydrogen might be located as well as where it could be commercially feasible to extract. These places with hydrogen have so-called reservoir rocks and geologic formations that prevent the gas from leaking into the atmosphere.

A few such places have already been identified such as one in Albania. There are various candidates to explore, even including an area in Kansas. The study’s authors have founded a company whose mission is to find these natural sources of hydrogen.

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Scientists Say Hidden Hydrogen Could Power the World for 170,000 Years

Photo, posted October 4, 2019, courtesy of Tony Sprezzatura via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

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

Decontaminating Drinking Water | Earth Wise

July 24, 2023 By EarthWise Leave a Comment

At least two billion people around the world often drink water that is contaminated with disease-causing microbes. Waterborne diseases are responsible for two million deaths each year, mostly among children under the age of five.

There are various ways to decontaminate water, including chemicals that can themselves produce toxic byproducts as well as using ultraviolet light, which takes fairly long to disinfect the water and requires a source of electricity.

Scientists at Stanford University and the SLAC National Accelerator Laboratory have recently invented a low-cost, recyclable powder that kills thousands of waterborne bacteria every second when the water containing it is exposed to ordinary sunlight. The discovery of this ultrafast disinfectant could be a tremendous benefit to the nearly 30% of the world’s population with no reliable access to safe drinking water.

The new disinfectant is a harmless metallic powder that works by absorbing both ultraviolet and high-energy visible light from the sun. It consists of nano-sized flakes of aluminum oxide, molybdenum sulfide, copper, and iron oxide. The key innovation is that when these four metallic ingredients are immersed in water, they all function together by reacting with the surrounding water and generating chemicals that quickly kill bacteria. The chemicals themselves don’t last long. They quickly break down in the water leaving completely safe drinking water.

The nontoxic powder is recyclable. It can be removed from water with a magnet. It can also be reused at least 30 times. Apart from its uses in less developed parts of the world, it could be valuable for hikers and backpackers who want to drink water from natural sources of unknown quality.

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New nontoxic powder uses sunlight to quickly disinfect contaminated drinking water

Photo, posted February 27, 2013, courtesy of Petras Gagilas via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Nitrous Oxide Is No Laughing Matter | Earth Wise

November 10, 2020 By EarthWise Leave a Comment

Carbon dioxide is the most well-known of greenhouse gases. But there are others deserving of their own spotlight. Nitrous oxide is one of them. It turns out that the same “laughing gas” once used by dentists as an anesthetic is pretty bad for the environment. In fact, it’s more than 300 times more potent as a greenhouse gas than carbon dioxide, and it can remain in the atmosphere for more than 100 years.

According to a new study by a team of international scientists, rising nitrous oxide emissions around the world are jeopardizing the climate goals of the Paris Agreement. The growing use of nitrogen fertilizers in global food production is increasing atmospheric concentrations of nitrous oxide.

The study, which was led by Auburn University and recently published in the journal Nature, finds that nitrous oxide emissions are increasing faster than any emission scenario developed by the Intergovernmental Panel on Climate Change. The current trajectory would lead to global mean temperature increases well above 3°C from pre-industrial levels. The Paris Agreement aims to limit global warming to less than 2°C.

According to the study, nitrous oxide levels have risen 20% from pre-industrial levels, with the fastest growth observed in the last 50 years due to emissions from human activities. The largest contributors to nitrous oxide emissions come from East Asia, South Asia, South America, and Africa. The United States, China, and India dominate nitrous oxide emissions from synthetic fertilizers, while Africa and South America dominate releases of nitrous oxide from natural sources, like livestock manure.

Nitrous oxide emissions pose an increasing threat to the climate.

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Nitrous oxide emissions pose an increasing climate threat, study finds

Photo, posted April 22, 2012, courtesy of Bill Meier via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Humans And Vertebrate Mortality

April 9, 2019 By EarthWise Leave a Comment

According to a new study, more than one-quarter of the planet’s land vertebrates die because of humans. This is a “disproportionately huge effect” on the other land vertebrates that share planet’s surface with us.

Researchers from the SUNY College of Environmental Science and Forestry and the U.S. Department of Agriculture reviewed 1,114 published studies in which nearly 43,000 animals had perished. Their study, which was recently published in the journal Global Ecology and Biogeography, found that 28% of the animals’ deaths were directly attributable to humans. The other 72% died from natural sources.

Mammals, birds, reptiles, and amphibians that died between 1970 and 2018 in the Americas, Asia, Africa, Europe, and Oceania were the foundation of the study. All of these vertebrates had been either collared or tagged as part of other research projects.

The researchers point out that humans are only one among more than 35,000 species of terrestrial vertebrates globally. The fact that humans are responsible for more than one-quarter of their deaths illustrates the profound magnitude of the problem. And that statistic is just the direct causes. According to the researchers, when urban growth and other land use changes that erode habitat are considered, the human impact is likely even greater.

The study found that the impact of humans across all the different species was not equal. In fact, larger animals were more likely to be killed by humans than smaller animals. Adult animals were more likely to be killed by humans than juveniles.

The researchers conclude that humans are such a major contributor to terrestrial vertebrate mortality that they could potentially impact both evolutionary processes and ecosystem functioning.

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On the land, one-quarter of vertebrates die because of humans

Photo, posted March 6, 2019, courtesy of USFWS Midwest Region via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.