concentrated

Climate change and hunger

July 14, 2025 By EarthWise Leave a Comment

Worldwide, people are producing more food than ever, but most of that production is concentrated into only a handful of places. For example, fully one third of the world’s wheat and barley exports come from Ukraine and Russia. Across the globe, several major crop-growing regions, including some in the United States, are heading towards sharp drops in harvests as a result of climate change.

These forthcoming changes are not only bad news for farmers, but they are also bad news for everyone who eats. According to a new study published in the journal Nature, it is going to become harder and more expensive to feed a more crowded and hungrier world.

Specifically, under a moderate greenhouse gas emissions scenario, six key staple crops will see an 11.2% decline by the end of the century, compared to a world without warming. The largest drops won’t be in the poorer, more marginal farmlands, but rather in places that are major food producers. These are places like the US Midwest that has long benefited by having both good soil and ideal weather for raising crops like corn and soy.

When the weather is not ideal, it can drastically reduce agricultural productivity. Extreme weather in many places has already damaged crops. Flooding has destroyed rice in Tajikistan, cucumbers in Spain, and bananas in Australia. Severe storms in the US this spring caused millions of dollars’ worth of damage to crops.

As the climate changes, rising average temperatures and changing rainfall patterns are likely to diminish yields and extreme weather events like droughts and floods could wipe out harvests more often. As climate change intensifies, agriculture is the most weather-affected sector of the economy.

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How climate change will worsen hunger

Photo, posted may 20, 2011, courtesy of Lance Cheung / USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

PFAS and groundwater

November 26, 2024 By EarthWise Leave a Comment

Per- and polyfluoroalkyl chemicals, more commonly known as PFAS, are a family of human-made chemicals that have been manufactured and used in a variety of industries since the 1940s. They provide water-resistance, oil-resistance, dirt-resistance, and corrosion-resistance to a wide range of products, including food wrappers and packaging, clothing, dental floss, nonstick cookware, textiles, and electronics.

Exposure to PFAS has been linked to birth defects, thyroid disease, liver disease, kidney disease, and cancer. These chemicals do not break down in the environment and therefore, over time, become concentrated in plants, animals, and people.

According to a new first-of-its kind study by scientists at the U.S. Geological Survey, more than 20% of the U.S. population could be drinking groundwater contaminated with PFAS. The study, which was recently published in the journal Science, found that those living in the Eastern U.S. are particularly likely to be exposed.

The study is the first to report national estimates of PFAS in untreated groundwater that supplies drinking water to private and public wells. The USGS research also provides the first estimate of the total number of Americans – anywhere from 71 to 95 million – who might be exposed to this contamination.

The researchers note that their estimates merely measure the existence of PFAS – before the water has undergone any treatment or filtering – meaning that, while they may be present, they may be at very low levels.

To find a link to the detailed USGS map showing the probability of PFAS groundwater contamination in your region, visit our website: EarthWiseRadio.org.

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PFAS in US Groundwater Interactive Dashboard

Predictions of groundwater PFAS occurrence at drinking water supply depths in the United States

Photo, posted January 12, 2008, courtesy of Andrew Kraker via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Moisture swing carbon capture

November 10, 2023 By EarthWise Leave a Comment

As the world grapples with limiting the amount of carbon dioxide in the atmosphere, there is a growing need to capture the carbon dioxide that is emitted as well as preventing it from being emitted in the first place. Carbon capture can be accomplished at the source of emissions (such as power plants) or it can be done by taking it out of the atmosphere. The latter is called “direct air capture”.

It is not at all clear whether direct air capture can be accomplished on a scale that would really make a difference and at an acceptable cost either in dollars or energy expended. But if it can be done that way, it would be a major tool in combatting climate change.

Direct air capture technology generally makes use of sorbent materials whose capacity to capture carbon dioxide and later release it is a function of temperature. The process requires significant amounts of energy to release the carbon dioxide that has been captured.

New research from Northwestern University makes use of the “moisture-swing” technique which uses materials whose ability to capture and release carbon dioxide depends on humidity rather than temperature. While it takes some amount of energy to humidify the volume of air containing the sorbent material, it is very small compared to temperature-driven systems.

There are many groups working with moisture-swing technology, but the Northwestern Group has identified a number of new sorbent materials with superior properties.

The fundamental questions of scalability and cost remain, but moisture-swing is a promising approach to direct air capture. If carbon dioxide can be pulled out of the atmosphere in large volumes, it can be concentrated and stored or converted into useful products.

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Pulling carbon dioxide right out of the air

Photo, posted May 15, 2020, courtesy of James Watt via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Shrinking Glaciers And Methane | Earth Wise

August 1, 2023 By EarthWise Leave a Comment

The Arctic region is warming much faster than the rest of the planet. In fact, according to a study published last year in the journal Nature, the Arctic has been warming nearly four times faster than the rest of the globe during the last 43 years. This rapid warming is leading to substantial reductions in sea ice, thawing of permafrost, shifts in wildlife populations, and changes in ocean circulation patterns, among other changes.

According to new research recently published in the journal Nature Geoscience, shrinking glaciers in the warming Arctic are exposing bubbling groundwater springs, which could provide an underestimated source of methane, a potent greenhouse gas. Methane is more than 25 times as potent as carbon dioxide at trapping heat in the atmosphere.

The study, which was led by researchers from the University of Cambridge and the University Centre in Svalbard, Norway, found large sources of methane gas leaking from groundwater springs unveiled by melting glaciers.

As glaciers retreat in the Norwegian archipelago of Svalbard and leave behind newly exposed land, groundwater beneath the Earth seeps upward and forms springs. In 122 out of the 123 springs studied, the research team found that the water was highly concentrated with dissolved methane. When the spring water reaches the surface, the excess methane can escape to the atmosphere.

Researchers are concerned that additional methane emissions released by the Arctic thaw could dramatically increase human-induced global warming. If this phenomenon in the Svalbard archipelago is found to be more widespread across the Arctic — where temperatures are quickly rising and glaciers melting — the methane emissions could have global implications.

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The Arctic has warmed nearly four times faster than the globe since 1979

Shrinking Arctic glaciers are unearthing a new source of methane

Photo, posted October 22, 2022, courtesy of David Stanley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Cheap Material For Carbon Capture | Earth Wise

September 12, 2022 By EarthWise Leave a Comment

The recently passed Inflation Reduction Act includes significant support for carbon capture technologies. Eliminating fossil fuel burning is essential for halting climate change, but in the interim, methods for capturing emissions of carbon dioxide and either storing it or turning it into usable products are increasingly necessary.

There are a variety of techniques being developed for carbon capture but at this point, none of them are commercially viable. The best technique in use today involves piping flue gases through chemicals called liquid amines, which bind CO2. The process requires large amounts of energy to release the bound carbon dioxide so it can be concentrated and stored. As a result, it is complicated and expensive.

Researchers at UC Berkeley, Stanford, and Texas A&M University have developed a carbon capture method using melamine, which is an inexpensive polymer used to make Formica, as well as low-cost dinnerware, industrial coatings, and other plastics. Porous melamine itself adsorbs CO2 to a limited extent. But the researchers discovered that adsorption could be much improved by adding the chemical DETA (diethylenetriamine) to bind the CO2. In addition, adding cyanuric acid increased the melamine pore size and radically improved CO2 capture efficiency even more.

The result is a material that is more efficient even than exotic carbon capture materials like metalorganic frameworks and is much cheaper and easier to make. The researchers aim to design equipment that can used in industrial facilities, attached to buildings and other structures, or even to the tailpipes of gas-powered vehicles.

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A simple, cheap material for carbon capture, perhaps from tailpipes

Photo, posted June 10, 2006, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.