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Air Pollution: The Greatest Danger | Earth Wise

June 27, 2022 By EarthWise Leave a Comment

The effort to reduce and ultimately eliminate the use of fossil fuels has largely been driven by the potentially catastrophic consequences of global climate change. The need to stop dumping greenhouse gases into the atmosphere has become increasingly urgent. But there is an equally compelling reason to stop burning fossil fuels. According to a study published in the journal Lancet Planetary Health, outdoor air pollution is “the largest existential threat to human and planetary health.”

Pollution of various types was responsible for an estimated 9 million deaths around the world in 2019. Half of those fatalities – 4.5 million deaths – were the result of outdoor air pollution coming from vehicles and industrial sources like power plants and factories.

The number of deaths attributed to air pollution has increased by 55% just since the year 2000.

The growth in air pollution deaths has offset a decline in deaths from other pollution sources that especially affect people living in extreme poverty, such as indoor air pollution and water pollution. Overall, countries with lower collective incomes tend to bear a disproportionate share of pollution deaths. Roughly 16% of deaths around the world are attributable to pollution, also resulting in more than $4 trillion in economic losses.

The peer-reviewed study was produced by the 2017 Lancet Commission on Pollution and Health. The study notes that despite the enormous health, social, and economic impacts of pollution, preventing it is largely overlooked in the international development agenda. The study calls upon governments, businesses, and other entities to abandon fossil fuels and adopt clean energy sources.

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Study Identifies Outdoor Air Pollution as the ‘Largest Existential Threat to Human and Planetary Health’

Photo, posted November 4, 2019, courtesy of Ninara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Americans And Lead Exposure | Earth Wise

April 4, 2022 By EarthWise Leave a Comment

Long-term exposure to lead can cause serious health problems, especially in children. Children are particularly vulnerable because their early years are characterized by rapid growth and brain development.

Lead is a powerful neurotoxin that can cause damage even at low levels of exposure. Lead poisoning can be acute, and can cause all sorts of health issues, including stomach pain, brain damage, and even death. Because lead accumulates in the body over time, lead poisoning can develop slowly. Exposure to lead can also contribute to a lower IQ and behavioral problems that can last a lifetime.

Lead is a naturally occurring element found in small amounts in earth’s crust. But as a result of human activities, lead can be found in all parts of the environment, including the air, soil, and water.

According to a new study recently published in the journal Proceedings of the National Academy of Sciences, approximately half of U.S. adults alive today were exposed to harmful levels of lead as children from the burning of leaded gasoline. The research team estimates that lead contamination has lowered those Americans’ IQ scores by more than two points on average.

In the study, the researchers used data on childhood blood-lead levels, leaded gasoline use, and population to gauge the lifetime exposure of every American adult in 2015. They found that more than 170 million Americans had exposure to concerning levels of lead as children. Those who grew up in the 60s and 70s, when the burning of leaded gasoline was at its peak, had the greatest exposure, losing up to six IQ points on average.

The legacy of lead exposure remains a persistent problem.

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Half of Americans Exposed to Harmful Levels of Lead as Children

Lead Exposure Remains A Persistent Problem

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Earth Wise is a production of WAMC Northeast Public Radio.

Mercury In The Amazon Rainforest | Earth Wise

March 8, 2022 By EarthWise Leave a Comment

Recent research has found that some of the highest levels of mercury pollution ever recorded are in a patch of pristine Amazonian rainforest. The international team of researchers discovered that illegal goldmining in the Peruvian Amazon is the source of the pollution.

Illegal miners separate gold particles from river sediments using mercury. Mercury binds to gold, forming pellets large enough to be caught in a sieve. The pellets are then burned in open fire ovens, releasing the mercury to the atmosphere, leaving the gold behind. The mercury smoke ends up being washed into the soil by rainfall, deposited onto the surface of leaves, or directly absorbed into leaf tissues.

Deforested areas had low levels of mercury, while the areas with the largest, densest old-growth trees captured huge volumes of atmospheric mercury, more than any other ecosystem studied in the entire world. Mercury levels were directly related to leaf area index: the denser the canopy, the more mercury it holds. Birds from this area have up to twelve times more mercury in their systems than birds from less polluted areas. Such high concentrations of mercury could provoke a decline of up to 30% in these birds’ reproductive success.

Small-scale artisanal gold mining is an important livelihood for local communities. Eliminating it outright may not be a viable solution but coming up with ways to continue to provide a sustainable livelihood while protecting communities from poisonous pollution is essential.

In the meantime, the forests are doing an important service by capturing much of the mercury and preventing it from getting into the general atmosphere and endangering more people and animals. Burning or harvesting the mercury-ridden trees would release the mercury back into the atmosphere.

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Modern Day Gold Rush Turns Pristine Rainforests into Heavily Polluted Mercury Sinks

Photo, posted August 24, 2016, courtesy of Anna and Michal via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fire And Ice | Earth Wise

January 17, 2022 By EarthWise Leave a Comment

In recent years, there have been countless stories about the effects of the changing climate. Many of those stories have been about the dwindling sea ice in the Arctic and many others have been about the worsening wildfires in the western United States. According to a recent study published by the Pacific Northwest National Laboratory, those two things are very much related.

As sea ice in the Arctic melts from July to October, sunlight warms the surrounding land and sea surfaces. The resulting differences in air pressure create and strengthens a vortex in the atmosphere above the heated area which spins counterclockwise like a cyclone.

The powerful vortex pushes the polar jet stream out of its typical pattern and diverts moist air away from the western United States. With the jet stream moved off its usual course, a second vortex, this time spinning clockwise, forms under the ridge of the polar jet stream above the Western U.S. This second vortex brings with it clear skies and dry conditions: fire-favorable weather.

Arctic sea ice has continually declined at least since the late 1970s. It is predicted that there will be periods of entirely iceless Arctic waters before the 2050s. In turn, conditions in the already fire-ravaged West are likely to be further exacerbated. More than three million acres have burned across California alone during the 2021 wildfire season.

Climate conditions in one part of the world can, over time, influence climate outcomes thousands of miles away. The research at Pacific Northwest Laboratory reveals how regional land and sea surface warming caused by Arctic ice melting can trigger hotter and drier conditions in the West later in the year.

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Fire and Ice: The Puzzling Link Between Western Wildfires and Arctic Sea Ice

Photo, posted July 28, 2018, courtesy of Bob Dass via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Liquid Fuels From Carbon Dioxide | Earth Wise

January 5, 2022 By EarthWise Leave a Comment

Most of the world’s energy demands are still being met by burning fossil fuels, thereby releasing carbon dioxide into the atmosphere. The energy system is in the midst of a transition to renewable sources such as solar and wind power, but it will be quite some time before fossil fuels are only a minor part of energy production. To reduce global warming, it will be necessary to prevent the carbon dioxide from fossil fuels from entering the atmosphere by capturing it and either locking it away or making use of it.

Recent research at several Chinese universities has developed a novel electrocatalyst that efficiently converts CO₂ to liquid fuels containing multiple carbon atoms. The main products of the high-efficiency reaction are ethanol, acetone, and n-butanol. Previous electrocatalystic methods have mostly produced simpler hydrocarbons – namely, ones with only a single carbon atom. The fuels the new catalyst produces are much more useful.

The catalyst is made from thin ribbons of a copper/titanium alloy that are etched with hydrofluoric acid to remove the titanium from the surface. The process results in a material with a porous copper surface on an amorphous CuTi alloy. The substance exhibits remarkably high activity, selectivity, and stability for catalyzing the reactions leading to the production of the hydrocarbon fuels.

Converting carbon dioxide into liquid fuels would be advantageous because they have high energy density and are safe to store and transport. Apart from preventing carbon dioxide from entering the atmosphere, the process could also be a way to make use of excess energy produced by solar and wind generation by essentially storing that energy in the form of liquid fuels.

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Liquid Fuels from Carbon Dioxide

Photo courtesy of Angewandte Chemie via Wiley-VCH.

Earth Wise is a production of WAMC Northeast Public Radio.

Batteries On Wheels | Earth Wise

December 24, 2021 By EarthWise Leave a Comment

Transportation accounts for nearly a quarter of the direct carbon dioxide emissions coming from burning fuel. As a result, electrification of transport is one of the major ways we can reduce emissions. Increasing the number of electric vehicles over time is essential for meeting emissions targets.

But electric vehicles have the potential to do more than deliver emissions reduction; they can also provide other energy services.

More and more electric cars provide over 200 miles of driving range, but most cars are actually driven no more than 30 miles a day. As a result, the fleet of electric cars represents a huge bank of energy stored in battery packs and mostly sitting around unused. This presents an opportunity to leverage this resource.

Car battery packs could be used to absorb excess renewable energy generated in the middle of the day (for example from solar installations) or at night (from wind farms) and potentially then to export stored energy to power homes and support the grid. This energy system is known as V2G, or vehicle-to-grid technology.

The University of Queensland in Australia has launched a unique international trial to see if the spare battery capacity in vehicles could be used for these purposes. The university has partnered with Teslascope, which is an online analytics platform used by Tesla owners to track the performance of their cars. Tesla owners wishing to be part of the study authorize the collection of their data and, in turn, receive a free 12-month subscription to the Teslascope service. The study will collect data from Tesla owners in Australia, the US, Canada, Norway, Sweden, Germany, and the UK.

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Can EV spare battery capacity support the grid?

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Earth Wise is a production of WAMC Northeast Public Radio.

Wine And Wildfire Smoke | Earth Wise

September 22, 2021 By EarthWise Leave a Comment

Rising global temperatures have made droughts and heatwaves more common and intense, leading to larger and more destructive wildfires. In 2020, wildfires in California blackened more than 4 million acres, the largest wildfire season on record. With its continuing drought, California has already had 1.5 million acres burned by wildfires this year, and the fires continue.

Wildfires can cause extensive damage throughout the agricultural industry by destroying crops and killing livestock. But the fires can have a unique effect on the wine industry: wine grapes can be affected by smoke taint.

Vineyards have demonstrated themselves to be good fire breaks. They definitely help prevent the movement of wildfires. But there is no way to stop smoke from the fires from drifting into vineyards. By far, the damage caused by smoke far outweighs direct losses from fires in vineyards.

Winemakers sometimes add subtle smoky notes to their vintages by aging them in toasted oak barrels. But wildfire smoke permeating vineyards – even from distant blazes – can end up making wines undrinkable. Smoke-tainted wines end up having unpleasant aromas that people describe as being like disinfectants or burnt rubber.

With wildfires an increasingly persistent presence in California, the state’s $43 billion wine industry is facing a major challenge. An estimated 165,000 to 325,000 tons of California wine grapes went unharvested last year, adding up to more than $600 million in losses from fire and smoke. The industry will need to figure out ways to detect and manage smoke taint as the problem isn’t going to go away.

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Wildfire Smoke: An Emerging Threat to West Coast Wines

Photo, posted July 25, 2021, courtesy of Felton Davis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Turning Atmospheric Carbon Into Useful Materials | Earth Wise

July 7, 2021 By EarthWise Leave a Comment

Plants have the ability to capture carbon dioxide from the atmosphere and incorporate it into leaves, fruits, wood, and other plant materials. This beneficial process is mostly temporary, as much of this carbon dioxide from plant matter ends up back in the atmosphere through decomposition, or even burning.

Researchers at the Salk Institute have proposed a more permanent fate for captured carbon by turning plant matter into a valuable industrial material called silicon carbide.

In a recent study published in the journal RSC Advances, Salk scientists transformed tobacco and corn husks into silicon carbide and evaluated and quantified the benefits of the process.

The researchers used a previously reported method to transform plant matter into silicon carbide in three stages and carefully tracked the carbon utilization at each stage.

Stage one is growing the plants. They used tobacco from seed, chosen for its short growing season. Then the harvested plants are frozen, ground into a powder, and treated with chemicals including a silicon-containing compound. Finally, the powder is subjected to a high-temperature process resulting in the production of silicon carbide.

Their analysis showed that much of the carbon sequestered by growing the plants could be preserved through the full process and the amount of energy required for the production of the silicon carbide (mostly from the high-temperature process) is comparable to current manufacturing processes for the material.

Permanently sequestering carbon from agricultural waste products by incorporating it into a valuable industrial material would be a valuable addition to strategies for reducing greenhouse gases in the atmosphere.

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Transforming Atmospheric Carbon Into Industrially Useful Materials

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Earth Wise is a production of WAMC Northeast Public Radio.

Overwintering Fires | Earth Wise

July 6, 2021 By EarthWise Leave a Comment

Fires that go on for long periods of time, surviving the snow and rain of winter to reemerge in the spring, are becoming more common in high northern latitudes as the climate warms. Such fires are called holdover fires, hibernating fires, overwintering fires, or even zombie fires. Whatever people choose to call them, this type of wildfire is occurring more often.

These smoldering fires start out as flaming fires but then enter an energy-saver mode. They start above ground but then smolder in the soil or under tree roots through the winter. They barely survive based on the oxygen and fuel resources that they have but can transition back into flaming fires once conditions are more favorable.

Dutch researchers used ground-based data with fire detection data from NASA’s Moderate Resolution Imaging Spectroradiometer instruments on the Terra and Aqua satellites to study fires in the boreal forests of Alaska and Canada’s Northwest Territories. They found a way to identify overwintering fires based on their unique characteristics.

Their data indicates that overwintering fires tend to be linked to high summer temperatures and large fire seasons. Between 2002 and 2018, overwintering fires generally accounted for a small amount of the total burned area in the region but in individual years with hot and severe fire seasons, the number can escalate. In 2008 in Alaska, for example, overwintering fires accounted for nearly 40% of the burned area.

Early detection of these overwintering fires could help with fire management and reduce the amount of carbon – which is stored in large amounts in the region’s organic soils – that gets released to the atmosphere during fires.

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Overwintering Fires on the Rise

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Earth Wise is a production of WAMC Northeast Public Radio.

Record Carbon Dioxide Levels | Earth Wise

June 29, 2021 By EarthWise Leave a Comment

The coronavirus pandemic caused a temporary dip in the burning of fossil fuels around the world as many human activities were diminished or curtailed entirely. Despite this, the amount of carbon dioxide in the atmosphere set a record in May, reaching the highest levels in human history.

Scientific instruments atop the Mauna Loa volcano in Hawaii measured an average of 419 parts per million for the month, according to analysis from both the Scripps Institution of Oceanography and the National Oceanic and Atmospheric Administration.

This level is about half a percent more than the previous record of 417 ppm, set in May of 2020. Carbon dioxide is the largest greenhouse gas contributor driving global warming and, according to scientists, there hasn’t been this much of it in the atmosphere for millions of years.

Global emissions of carbon dioxide were actually 5.8 percent lower in 2020 than 2019, as a result of pandemic lockdowns. This was the largest one-year drop ever recorded. But humanity was still responsible for emitting more than 31 billion tons of carbon dioxide last year. About half of that CO2 is absorbed by the world’s trees and oceans, but the other half lingers in the atmosphere for thousands of years, gradually warming the planet via the greenhouse effect.

As long as we keep emitting carbon dioxide, it is going to continue to pile up in the atmosphere. The only way to stop it is for the world’s nations to zero out their net emissions, mostly by switching away from fossil fuels to technologies that do not emit carbon dioxide, such as electric vehicles fueled by wind, solar, or nuclear power.

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Carbon Dioxide in Atmosphere Hits Record High Despite Pandemic Dip

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Earth Wise is a production of WAMC Northeast Public Radio.

Forests And Climate Change | Earth Wise

June 17, 2021 By EarthWise Leave a Comment

A carbon sink is anything that absorbs more carbon from the atmosphere than it releases. Examples of carbon sinks include the ocean, soil, and plants. In contrast, a carbon source is anything that releases more carbon into the atmosphere than it absorbs. Volcanic eruptions and burning fossil fuels are two examples.

Forests are among the most important carbon sinks. Trees remove carbon from the air and store it in their trunks, branches, and leaves, and transfer some of it into the soil. But in many regions, deforestation, forest degradation, and the impacts of climate change are weakening these carbon sinks. As a result, some climate activists advocate for large-scale tree-planting campaigns as a way to remove heat-trapping CO2 from the atmosphere and help mitigate climate change.

But according to a new study recently published in the journal Science, planting new trees as a substitute for the direct reduction of greenhouse gas emissions could be a pipe dream. While planting trees is easy, inexpensive, and can help slow climate warming, the ongoing warming would be simultaneously causing the loss of other trees. Instead, the research team says it makes more sense to focus on keeping existing forests healthy so they can continue to act as carbon sinks, and to reduce emissions as much as possible and as quickly as possible.

But keeping forests healthy will require a paradigm shift in forest management. Instead of trying to maintain forests as they were in the 20th century, the research team says forests need to be managed proactively for the changes that can be anticipated.

One thing is clear: We cannot plant our way out of the climate crisis.

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Forests and climate change: ‘We can’t plant our way out of the climate crisis’

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Earth Wise is a production of WAMC Northeast Public Radio.

Concrete Production And Diminishing Coal Burning | Earth Wise

June 5, 2020 By EarthWise Leave a Comment

Coal burning is still one of the primary means of generating electricity in the United States, but its use is diminishing and doing so fairly rapidly. The coal burning process produces residual, incombustible materials. One of them is fly ash, which is composed of fine, glassy, rounded particles rich in silicon, aluminum, calcium, and iron oxides. Fly ash is captured from coal plant flue gas by precipitators and bag filters. It turns out that two-thirds of this fly ash is not dumped into landfills or impoundments, but rather is put to use.

Because of its chemical and physical characteristics, fly ash can substitute for a portion of portland cement in concrete. Using this byproduct material in making cement actually reduces its cost. Beyond cost, the addition of fly ash as a so-called supplementary cementitious material or SCM improves concrete’s long-term strength and reduces porosity and permeability. It reduces the risk of thermal cracking and provides good long-term mechanical properties.

The amount of fly ash used in concrete products increased by 5% between 2011 and 2017 while the amount produced dropped by 36%. Concrete production continues to increase steadily while fly ash production is steadily dropping.

Therefore, the concrete industry is looking for alternative sources of SCM. The most obvious is the approximately 1/3 of fly ash that hasn’t been used to make concrete. Much of that is landfilled or ponded onsite at power plants. So, opportunities exist for excavating or dredging and recovering these materials.

As coal burning goes away, concrete manufacturing needs to make some changes.

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What Does the Changing Face of Electricity Production Mean for Concrete?

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Earth Wise is a production of WAMC Northeast Public Radio.

The Problem Of Gas Flaring | Earth Wise

January 9, 2020 By EarthWise Leave a Comment

Gas flaring is the burning off of flammable gas released by pressure relief values during over-pressuring of plant equipment at petroleum refineries, chemical plants, natural gas processing plants, and a variety of oil and gas production plants. Flaring is also used during plant startups and shutdowns.

A new study by Rice University concludes that reducing gas flaring would benefit both the environment and the economy. Flaring and venting of gas in West Texas’s Permian Basin and certain other parts of the U.S. have reached levels that the intended result of burning gas to allow oil extraction now looks more like wasting one resource to produce another.

At current rates, enough gas is flared in the Permian Basin to yield nearly 5 million metric tons of exportable liquid natural gas if it was captured and liquified. At these rates, the wasted gas could fill the largest sized LNG carrier every ten days. If that liquified natural gas was exported to China and used in a power plant, it would displace 440,000 metric tons of coal burned to generate electricity.

Burning natural gas to heat homes, power industrial processes, or generate electricity all emit carbon dioxide, but at least these things also perform valuable functions. Flaring gas produces CO2 as well as other combustion products but doesn’t even do anything useful. The venting of unburned gas, which also takes place with some frequency, is even worse since it is dumping methane directly into the atmosphere.

Across the U.S., some 14.1 billion cubic meters of natural gas was flared in 2018, equivalent to nearly 9 million metric tons per year of LNG. In energy terms, that is equivalent to more than one-third of the total LNG volume U.S. firms actually exported that year.

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Reducing gas flaring will benefit economy and environment, says Baker Institute expert

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Earth Wise is a production of WAMC Northeast Public Radio.

The Arctic As A Carbon Source

December 16, 2019 By EarthWise Leave a Comment

According to a new NASA-funded study, the Arctic may now be a source for carbon in the atmosphere rather than being the sink for it that is has been for tens of thousands of years.

The study, published in Nature Climate Change, warns that carbon dioxide loss from the world’s permafrost regions could increase by more than 40% over the next century if human-caused greenhouse gas emissions continue at their current pace. Worse yet, carbon emitted from thawing permafrost has not even been included in most climate models.

Permafrost is the carbon-rich frozen soil and organic matter that covers nearly a quarter of Northern Hemisphere land area, mostly in Alaska, Canada, Siberia, and Greenland. Permafrost holds more carbon than has ever been released by humans from fossil fuel burning, but it has been safely locked away by ice for tens of thousands of years.

As global temperatures rise, the permafrost is starting to thaw and release greenhouse gases into the atmosphere.

The recent findings indicate that the loss of carbon dioxide during the winter in the Arctic may already be offsetting carbon uptake during the growing season. The researchers compiled on-the-ground observations of carbon dioxide emissions across many sites and combined these with remote sensing data and modeling. They estimate that the permafrost region is now losing 1.7 billion metric tons of carbon during the winter season but taking up only 1 billion during the growing season.

The major concern is that as the Arctic continues to warm, more carbon will be released into the atmosphere from the permafrost region, which will further the warming. Climate modeling teams across the globe are trying to incorporate these findings into their projections.

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Arctic Shifts to a Carbon Source due to Winter Soil Emissions

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Earth Wise is a production of WAMC Northeast Public Radio.

Air Quality In The U.S.

November 13, 2019 By EarthWise Leave a Comment

Globally, poor air is a serious problem. According to the World Health Organization, exposure to air pollution is linked to the premature deaths of an estimated 7 million people every year. In fact, 91% of the people on the planet live in places where air pollution exceeds WHO guideline limits.

In the United States, air pollution has dramatically improved over the last four decades due in large part to federal regulations put in place under the Clean Air Act of 1970. Fine particulate matter (known as PM2.5) and other pollution, including ozone, sulphur dioxide, and nitrogen dioxide, have all decreased during this time span.

But according to recent research, this trend has unfortunately done an about-face. New data reveals that air pollution has increased nationally since 2016. An analysis of Environmental Protection Agency data by researchers at Carnegie Mellon University found that, on average, fine particulate pollution increased 5.5% across the country between 2016 and 2018.

This increase in fine particulate pollution was associated with nearly 10,000 additional premature deaths in the United States during that time period.

According to researchers, there are several factors likely causing this uptick in unhealthy air, including increases in both driving and the burning of natural gas. Wildfires out west are also thought to be a major contributor.

The researchers also suggest that a decrease in enforcement of the Clean Air Act may also be playing a role. The law put in place strict air pollution standards for vehicles, factories, power plants, and other sources, and is credited with saving hundreds of thousands of lives.

It’s time for clean air to be recognized as a basic human right.

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America’s Air Quality Worsens, Ending Years of Gains, Study Says

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Wildfires And Carbon

September 17, 2019 By EarthWise Leave a Comment

This summer has been an unprecedented year for fires in the Arctic. Major fires have burned throughout the Arctic in Russia, Canada, and Greenland. In total these fires released 50 million tons of carbon dioxide in June alone, which is as much as Sweden emits in an entire year.

In an average year, wildfires around the world burn an area equivalent to the size of India and emit more carbon dioxide to the atmosphere than global road, rail, shipping and air transport combined.

Ordinarily, this is part of a natural cycle. As vegetation in burned areas regrows, it draws CO2 back out of the atmosphere through photosynthesis. This is part of the fire-recovery cycle, which can take less than a year in grasslands, but decades in forests. But in Arctic or tropical peatlands, full recovery may not occur for centuries.

A recent study looked at and quantified the important role that charcoal plays in helping to compensate for carbon emissions from fires. In wildfires, some of the vegetation is not consumed by burning, but instead is transformed to charcoal – referred to as pyrogenic carbon. This carbon-rich material can be stored in soils and oceans over very long time periods.

Researchers have combined field studies, satellite data, and modelling to quantify the amount of carbon that is placed in storage in the form of charcoal. Their results are that the production of pyrogenic carbon amounts to about 12% of the CO2 emissions from fires and can be considered a significant buffer for landscape fire emissions.

Charcoal does not represent a solution to the problem of increasingly intense wildfires, but it is important to take it into account in understanding what is happening.

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