surface area

Emissions and the Great Salt Lake

September 4, 2024 By EarthWise Leave a Comment

The Great Salt Lake in Utah has been described as a puddle of its former self. The lake’s size fluctuates naturally with seasonal and long-term weather patterns, but the lake has been experiencing decline for decades as Utahans take water out of the rivers and streams that once fed the lake. Over recent decades, the lake has lost 73% of its water and 60% of its surface area.

For years, scientists and environmental leaders have warned that the Great Salt Lake is headed toward a catastrophic decline. Recent research has found that the lake’s desiccating shores are becoming a significant source of greenhouse gas emissions. Scientists have calculated that the dried-out portions of the lakebed released about 4.1 million tons of carbon dioxide and other greenhouse gases in 2020.

The recent study, published in the journal One Earth, suggests that the Great Salt Lake – which is largest saltwater lake in the Western Hemisphere – as well as other shrinking saline lakes around the world could become major contributors of climate-warming emissions.

The shrinking back of the water has exposed a dusty lakebed that is laced with arsenic, mercury, lead, and other toxic substances. Some are naturally occurring, and others are the residue of mining activity in the region. These substances threaten to increase rates of respiratory conditions, heart and lung disease, and cancers.

As the lake shrinks, it is becoming saltier and uninhabitable to native flies and brine shrimp and may increasingly become unable to support the 10 million migratory birds and wildlife that frequent it.

The new research about greenhouse gas emissions just adds to a dire list of environmental consequences brought on by the lake’s steep decline.

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Shrinking Great Salt Lake Becoming Source of Heat-Trapping Gas

Photo, posted January 20, 2020, courtesy of Matthew Dillon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Potential for floating solar

July 16, 2024 By EarthWise Leave a Comment

As installations of utility-scale solar power continue to expand around the world, there is the issue of where to put them. They do take up considerable amounts of space and, in many places, available land is at a premium.

An alternative to taking up available land with solar panels is to deploy them on the surfaces of lakes and reservoirs. A study by researchers at Bangor and Lancaster Universities in the UK calculated the potential electrical output for floating photovoltaic installation on nearly 68,000 lakes and reservoirs around the world. The lakes and reservoirs selected were no more than 6 miles from a population center, were not in a protected area, and didn’t dry up and didn’t freeze for more than six months each year. The calculations were based on covering just 10% of the surface area of the bodies of water.

The calculations were evaluated country-by-country. Five countries could meet their entire electricity needs by floating installations including Papua New Guinea, Ethiopia, and Rwanda. Many countries, mostly in Africa, South America, and Central Asia, could get between 40% and 70% of their electricity this way. Most European countries could only meet a few percent of their electricity needs from floating solar, but even that could be significant.

There are other benefits to floating solar apart from freeing up land. The panels stay cooler, making them more efficient, and reservoirs lose less water through evaporation and the growth of algal blooms is reduced because there is less light reaching the water.

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Some countries could meet their total electricity needs from floating solar panels, research shows

Photo, posted November 25, 2015, courtesy of Smabs Sputzer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Converting A Toxin Into An Industrial Chemical | Earth Wise

January 16, 2020 By EarthWise Leave a Comment

Nitrogen dioxide is a prominent air pollutant produced by internal combustion engines burning fossil fuels as well as by a variety of industrial processes. It is a toxic material associated with a number of respiratory illnesses.

Researchers at the University of Manchester in the UK along with an international team of scientists have developed a new advanced material that can convert nitrogen dioxide from an exhaust gas stream into useful industrial chemical using only water and air.

The material is a metal-organic framework (or MOF) that provides a selective, fully reversible, and repeatable capability to capture nitrogen dioxide. MOFs are tiny three-dimensional structures that are porous and can trap gases inside as though there were tiny cages. MOFs have enormous amounts of surface area for their size. One gram of material can have a surface area as large as a football field.

The material, named MOF-520, can capture nitrogen dioxide at ambient temperatures and pressures and even at low concentration and during flow in the presence of moisture, sulfur dioxide, and carbon dioxide. Such conditions are typical of the exhaust of internal combustion engines. In fact, the process works best at the typical temperature of automobile exhausts.

Once the nitrogen oxide is absorbed, treating the material with water in air converts it into nitric acid and restores the MOF for additional use. Nitric acid is the basis of a multi-billion dollar industry with uses including agricultural fertilizers, rocket propellant, and nylon. Thus, there is great potential for recouping the costs of using the MOF technology and even profiting from it.

It would be great to convert a toxic pollutant into valuable industrial chemicals.

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Clean air research converts toxic air pollutant into industrial chemical

Photo courtesy of the University of Manchester.

Earth Wise is a production of WAMC Northeast Public Radio.