Earth Wise

A look at our changing environment.

You are here: Home / Archives for Posts

Renewables Surpass Coal | Earth Wise

By Leave a Comment

In 2019, energy consumption in the U.S. from renewable sources exceeded consumption from coal for the first time since before 1885.  This has come about from a combination of the continued decline in the amount of coal used for electricity generation as well as the continued growth in renewable energy, mostly from wind and solar.

Until the mid-1800s, burning wood was the main source of energy in the U.S. and, in fact, it was the only commercial-scale renewable energy source until the first hydroelectric plants came online in the 1880s.  Coal was used as fuel for steamboats and trains and making steel but only started to be used to generate electricity in the 1880s.

In 2019, U.S. coal consumption decreased for the sixth consecutive year and fell to its lowest level in 42 years.  Natural gas has displaced much of the energy generation from retired coal plants.

At the same time, renewable energy consumption in the U.S. grew for the fourth year in a row to a record high level, almost entirely as a result of the growing use of wind and solar power.  In 2019, wind power surpassed hydroelectric power for the first time and is now the most-used source of renewable energy for electricity generation in the U.S.

Coal was once commonly used in the industrial, transportation, residential, and commercial sectors.  Today, in the U.S., it is mostly used to generate electricity, and that use is rapidly declining.

Electricity consumption for 2020 is likely to be anomalous in many ways as a result of the Covid-19 pandemic shutdowns.  From all indications, however, the role of renewable energy will only have been increased during the shutdown period.

**********

Web Links

U.S. renewable energy consumption surpasses coal for the first time in over 130 years

Photo, posted July 26, 2013, courtesy of Don Graham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Disappearing Rainforests | Earth Wise

By Leave a Comment

Forest loss is a major contributor to climate change, and it is continuing at a rapid pace.  The tropics lost about 30 million acres of tree cover in 2019, a third of which was within humid tropical primary forests, which are especially important for biodiversity and carbon storage.  To put that loss in a human-scale perspective, it is the equivalent of losing a football field of primary forest every six seconds for the entire year.

The losses last year were 2.8% higher than in the previous year, and these losses have continued over the past 20 years despite worldwide efforts to halt deforestation.  

Brazil single-handedly accounted for over a third of all global loss of humid tropical primary forests. Bolivia experienced record-breaking tree cover loss due to fires.  The losses in its forests were 80% greater than in any previous year.  The fires were often started by people who were trying to clear land for agriculture but had the fires go out of control. Several countries in Africa’s Congo Basin also experienced sustained or worsening forest loss. 

Indonesia, often the focus of the world’s attention for its deforestation activities, actually saw a 5% reduction in primary forest loss in 2019.  It was the third year in a row for lower losses.  The now-permanent moratorium on clearing forests for oil palm plantations and logging seems to be working.

Going forward, the coronavirus pandemic poses additional threats to the world’s forests in the near future.  There may be a tendency to sacrifice forests in pursuit of economic recovery, which will only lead to future complications for the health and livelihoods of millions of people around the world.

**********

Web Links

We Lost a Football Pitch of Primary Rainforest Every 6 Seconds in 2019

Photo, posted February 7, 2011, courtesy of Chad Skeers via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Turning Dead Trees Into Biomass Energy | Earth Wise

By Leave a Comment

California has suffered from numerous large wildfires in recent years.  The two largest in the past century took place in 2017 and 2018, and just these two alone burned nearly 750,000 acres, destroyed over 1,200 structures, and killed 24 people.

Apart from the fires, drought, the warming climate, and bark-beetle infestations have killed 147 million California trees since 2013, most of them along the spine of the Sierra mountains.  These dead trees represent a significant danger in forthcoming fire seasons as they threaten to burn with enormous intensity.

There are now biomass projects in California that thin trees in overcrowded forests and remove dead and diseased trees and turn them into wood chips to supply community biomass facilities that burn them to produce heat and electricity.

Proponents say these projects help rebuild rural communities by creating jobs, while at the same time reducing fire risk. 

There are critics of these programs who claim that they are damaging and destroying ecosystems.    They also point out that burning forest fuels emits 50% more carbon than burning coal and three times as much as burning natural gas.  This is true of biomass in general but is mitigated by the fact that it in principle the carbon can be recaptured by new forest growth.

However, the dominant argument about emissions is that wildfires emit far more carbon dioxide than biomass plants, or much of anything else, for that matter.  In 2018 alone, California wildfires released 50% more carbon dioxide than California’s entire industrial sector.  So, reducing the extent of wildfires is a big deal for many reasons.

**********

Web Links

In California, A Push Grows to Turn Dead Trees into Biomass Energy

Photo, posted August 24, 2016, courtesy of the USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plant-Based Bottles | Earth Wise

By Leave a Comment

Single-use plastic soda and water bottles are a real problem.  Every year, billions of them are produced – comprising nearly 300 million tons of plastic that mostly ends up in landfills or in the ocean.   This discarded plastic ends up on remote islands, in the snow atop mountains, and in trenches in the deepest parts of ocean.

There has been increasing pressure on beverage companies to put an end to this environmental disaster, but the convenience and economy of disposable bottles is just too attractive.

These bottles are made of plastic derived from oil and once they are produced, they take decades or even centuries to decompose.  Recycling them is a not-starter because it is cheaper to just make new ones.

A possible solution has emerged.  A Dutch company called Avantium has found a way to take plant sugars and transform them into a plastic capable of standing up to carbonated beverages like soda and beer but that will also break down in as little as a year in a composter or 3 years if left exposed to the elements.

Coca Cola and Carlsberg are working with Avantium to develop new drink packaging based on their material that could be in stores as soon as 2023.  The new packaging would be quite different from what we use today.  Instead of a clear or tinted bottle, beverages would come inside a cardboard container with a liner made of plant-based plastic.

It may take a while for people to get used to the change, but we have already managed to get used to milk, juice and other liquids coming in cardboard containers instead of glass or plastic bottles.  The benefits to the planet would make the effort well worthwhile.

**********

Web Links

Plant-Based Bottles Could Degrade In One Year

Photo courtesy of Avantium.

Earth Wise is a production of WAMC Northeast Public Radio.

Powering Amazon By The Sun | Earth Wise

By Leave a Comment

Amazon.com is a multinational conglomerate company that sells nearly $300 billion dollars a year worth of products, employs over 800,000 people, and by any measure, consumes a tremendous amount of resources.  In terms of its environmental impact, Amazon is estimated to be responsible for the emission of 50 million tons of CO2 annually, which is more than the yearly total for countries like Switzerland, Ireland, New Zealand, Denmark, and about 140 other countries.

Amazon is trying to reduce its environmental impact.  The company recently announced five new renewable energy projects in China, Australia and the U.S. as part of its commitment to reach 80% renewable energy by 2024, 100% renewable energy by 2030, and to reach net zero carbon by 2040.

The projects include a 100 MW solar project in Shandong, China, a 105 MW solar project in New South Wales, Australia, two solar projects in Ohio (one 200 MW and one 80 MW), and a 130 MW solar project in Virginia.

To date, Amazon has announced 31 utility-scale wind and solar renewable energy projects as well as 60 solar rooftops on fulfillment centers and sort centers around the world.  Taken together, these projects provide almost 3 GW of capacity and will deliver more than 7.6 million MWh of renewable energy annually.

In order for the world to meet the climate goals set by the Paris Agreement, it will take more than just countries to make and keep commitments.   Whatever else one may think about Amazon’s place in the world, their latest efforts for the environment are a big step in the right direction.

**********

Web Links

Amazon announces five new utility-scale solar projects to power operations in China, Australia, and the US

Photo, posted November 16, 2018, courtesy of Todd Van Hoosear via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Making Use Of Invasive Seaweed | Earth Wise

By Leave a Comment

In recent years, millions of tons of brown Sargassum seaweed have formed gigantic blooms stretching all the way across the Atlantic Ocean from West Africa to the Gulf of Mexico.  The seaweed has become a problem for shorelines in the Caribbean, the Gulf of Mexico, and the east coast of Florida.  The massive increase in seaweed populations is related to changes in ocean chemistry resulting from nutrients from fertilizer use entering the water as well as from changes to the climate affecting ocean currents and temperatures.  The seaweed is harming the tourism industry as well as fisheries and ocean ecosystems.

Cleaning up the seaweed that washes ashore is labor-intensive and therefore expensive.  A research team led by two British universities has developed a cheap and simple way to pre-process seaweed to facilitate making it into bulk chemicals and biofuels.  With the new process, cleaning up the seaweed can be both economically and environmentally viable.

Previous techniques for processing seaweed generally required removing it from the saltwater, washing it in fresh water, and drying it – all of which add significant costs.  The new technique makes use of catalysts to release sugars from untreated seaweed that feed a yeast to produce a palm oil substitute.  At the same time, the process creates heat and pressure, turning the residual materials into a bio-oil that can be processed further into fuels, and a high-quality, low-cost fertilizer.

Apart from getting economic value out of the seaweed that is collected, any plastic collected alongside the seaweed can be converted to useful materials as well. 

It appears that the seaweed scourge is here to stay, so finding an economically viable way to deal with it is a welcome development.

**********

Web Links

Solve invasive seaweed problem by turning it into biofuels and fertilisers

Photo, posted August 10, 2015, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

PPE Pollution | Earth Wise

By Leave a Comment

While the COVID-19 pandemic and its shutdown of so many human activities has reduced many kinds of pollution, it has also managed to create a new source of pollution:  face masks and sanitary gloves.

Divers from a French non-profit organization called Operation Clean Sea are already finding gloves, masks, and hand sanitizer bottles beneath the waves of the Mediterranean, along with the usual litter of disposable cups and aluminum cans. In France, authorities have ordered 2 billion disposable masks. Given that, there may soon be the risk of having more masks in the Mediterranean than jellyfish.  In Hong Kong, face masks have been piling up on beaches and nature trails.  Even in Hong Kong’s isolated and uninhabited Soko Islands, dozens of masks are showing up on a small stretch of beach.

Disposable masks may feel like soft cotton, but almost all of them are made from non-biodegradable material such as polypropylene.  When such masks are discarded into storm drains, they end up in rivers and seas.  With a lifespan of hundreds of years, these masks are an ecological timebomb.  Land-based activity accounts for 80% of ocean pollution, and half of that is a direct result of single-use plastics.  Many of the CDC’s recent recommendations for reopening offices and businesses actually recommend the increased use of them, and for sensible reasons.

The best we can all do is to wear reusable masks and to try to wash our hands more often rather than putting on another pair of latex gloves.  Given that there are alternatives, we don’t need to make plastic the solution to protect us from Covid-19.

**********

Web Links

COVID-19 Masks Are Polluting Beaches and Oceans

Photo, posted March 28, 2020, courtesy of Michael Swan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

More Dam Failures Likely | Earth Wise

By Leave a Comment

Two dams in Central Michigan were breached by rain-swollen floodwaters in May and forced the evacuation of tens of thousands of residents and prompted officials to warn of life-threatening danger from a flooded chemical complex and a toxic waste cleanup site.  Engineers say that most dams in the U.S. were designed many decades ago – in some cases, a century ago – and are not suited to a warming world with ever stronger storms.

The dams in Michigan gave way for the same reason behind most dam failures:  they were overwhelmed by water, in this case by five inches of rain falling over two days after earlier storms had saturated the ground and swollen rivers.

It can’t be proven whether this specific set of events was triggered by climate change, but global warming is definitely causing some regions to become wetter and is increasing the frequency of extreme storms.  And these trends are expected to continue as the world continues to warm.

All of this puts more of the 91,500 dams in the U.S. at greater risk of failing.  The American Society of Civil Engineers, in its latest report card on infrastructure issued in 2017, gave the nation’s dams a “D” grade.

Historically, dams have been designed based on past weather history to predict the magnitude of the maximum potential flood that a dam would have to withstand.  There was no expectation that future weather patterns might be very different.  Infrastructure designers will clearly need to change their practices.

For existing dams, operational changes might be called for, such as reducing water levels in anticipation of more extreme storms.  Upgrades might include changing spillway designs to accommodate larger water volumes over a longer time period.

**********

Web Links

‘Expect More’: Climate Change Raises Risk of Dam Failures

Photo courtesy of Eye in the Sky/Youtube.

Earth Wise is a production of WAMC Northeast Public Radio.

Heat-Resistant Coral | Earth Wise

By Leave a Comment

Coral reefs are in decline all over the world.  Corals are under increasing pressure as water temperatures rise and the frequency and severity of coral bleaching events increase.  Nowhere is this more evident than in Australia’s Great Barrier Reef system, where severe bleaching events have happened in three of the past five years. Long-term prospects for the survival of the world’s largest reef system are now considered to be poor.

A team of scientists at Australia’s national science agency – the Commonwealth Scientific and Industrial Research Organization – along with the Australian Institute of Marine Science and the University of Melbourne have successfully produced in a laboratory setting a coral that is more resistant to increased seawater temperatures.

The team made the coral more tolerant to temperature-induced bleaching by bolstering the heat tolerance of the microalgae symbionts that live inside the coral tissue.  They isolated the microalgae from coral and cultured it in the laboratory using a technique called “directed evolution”.  Over the course of four years, they exposed the microalgae to increasingly warmer temperatures.  When the heat-adapted strain of algae was reintroduced into coral larvae, the newly established coral-algal symbiosis was more heat tolerant than the original one.  The heat-tolerant microalgae are better at photosynthesis and improve the heat response of the coral animal.

The next step is to further test the algal strains in adult colonies across a range of coral species.  This groundbreaking research provides a promising and novel tool to increase the heat tolerance of corals and might potentially lead to a way to save the Great Barrier Reef as the world continues to warm.

**********

Web Links

Scientists successfully develop heat resistant coral to fight bleaching

Photo, posted September 22, 2010, courtesy of NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Giant U.S. Offshore Wind Project Begins | Earth Wise

By Leave a Comment

In recent years, the Bureau of Offshore Energy Management – the agency that oversees energy projects in federal waters – has been granting leases for offshore wind projects in the waters of multiple states on the East Coast.  Up until now, none of these leases have actually resulted in the deployment of any wind turbines because the process of gaining approvals, project plans, surveys, funding and other requirements is a long and tortuous one.

In late May, the first offshore wind turbine in U.S. federal waters was installed 27 miles offshore from Virginia.  The 6-MW Siemens turbine is one of two turbines making up the Coastal Virginia Offshore Wind pilot project.  The pilot project is expected to be operational later this year.  This project is the first to receive go-ahead approval by the BOEM.

The CVOW project is a development by Dominion Energy, a Virginia-based utility that operates in 20 states.  Dominion’s project will eventually be a 2.64 GW mega-farm that could be the largest offshore wind farm in the world.  Construction of the main project is expected to begin in 2024.  It will be sited in the seabed of a 112,800-acre lease area.  The site is currently being surveyed to determine potential impacts to ocean and sea life.

Dominion Energy has made multiple commitments to emissions reduction and the massive offshore wind farm is an important part of its efforts to meet those commitments.  The CVOW pilot project is only the second offshore wind installation in the U.S.  The first, the Block Island Wind Farm in Rhode Island, is in state waters and did not require BOEM approval.

**********

Web Links

A ‘monumental day’ for US offshore wind as first turbine is installed in federal waters

Photo, posted May 13, 2011, courtesy of the Department of Energy and Climate Change via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Microplastics And Florida’s Birds of Prey | Earth Wise

By Leave a Comment

Plastic debris comes in all different shapes and sizes, but those that are less than five millimeters in length are called microplastics.  Some microplastics come from larger plastic debris that degrades into smaller bits over time.  Another type of microplastics – called microbeads – are intentionally manufactured tiny plastic beads that are added as exfoliants to some health and beauty products. 

According to a new study published in the journal Environmental Pollution, researchers have confirmed and quantified the presence of microplastics in terrestrial and aquatic birds of prey in Florida for the first time.  This research is important because these birds of prey, including ospreys, hawks, and owls, are critical to maintaining a healthy ecosystem.  The accumulation of microplastics in their digestive systems could lead to a myriad of health issues, including starvation.  

Working with the Audubon Center for Birds of Prey in Florida, the research team from the University of Central Florida was able to examine the stomachs of 63 deceased birds.  The team found microplastics in every bird it examined, extracting nearly 1,200 pieces of plastic in total.  Microfibers represented 86% of the plastic pieces. 

It’s common for plastic microfibers to enter ecosystems through the wastewater from washing machines.  A 2016 study found that 700,000 plastic fibers come off in a typical wash.  While there are lots of variables, synthetic fabrics account for 60% of the material used in clothing worldwide. 

To help cut down on plastic in the environment, the research team suggests removing plastics from open landfills, purchasing only natural fabrics and clothing, and modifying water treatment facilities to capture microplastics. 

**********

Web Links

Microplastics found in Florida’s birds of prey for first time

Photo, posted April 15, 2016, courtesy of Andy Morffew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Floating Turbines For Offshore Wind | Earth Wise

By Leave a Comment

Offshore wind is big in Europe.  There are more than 5,000 offshore wind turbines across 12 European countries with a total capacity of more than 22 gigawatts.  Almost every one of those turbines sits on a long tower sunk into the seabed and bolted into place in places where the water is 60 to 160 feet deep.

But off the coast of northern Scotland, there is the Hywind Wind Park which has five 574-foot-tall turbines located 15 miles offshore where the water is 300 feet deep.  The giant masts and turbines sit on buoyant concrete-and-steel keels that allow them to stand upright and float on the water like a giant buoy.  The giant cylindrical bases are held in place with mooring cables attached to anchors that sit on the seafloor.

A key advantage of floating turbines is that they can access outlying ocean waters up to half a mile deep, which is where the world’s strongest and most consistent winds blow.  Another advantage is that such turbines can be installed over the horizon, out of sight of coastal residents who might not like to have wind turbines visible in their scenic ocean views.

Floating wind power has enormous potential for contributing to the expansion of renewable energy.  Offshore wind is still quite a bit more expensive than land-based turbines, and the cost of electricity from distant floating turbines is more than that from near-shore wind turbines.   But all of these costs are likely to come down with improving technology and increased production volume.

There are real challenges to the expanded used of floating wind farms, but the promise of harnessing so much of the open seas for electricity generation is an attractive proposition.

**********

Web Links

Will Floating Turbines Usher in a New Wave of Offshore Wind?

Photo, posted July 17, 2017, courtesy of Crown Estate Scotland via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Second Life For Electric Car Batteries | Earth Wise

By Leave a Comment

The number of electric cars around the world is growing steadily.  Battery technology continues to improve and the battery packs in the cars can have a long life.  Generally, the batteries are considered to require replacement only when their range has dropped below 80% of its original value.  Many are warranted to last for 8 to 10 years or more than 100,000 miles.  Some seem to do much better than that.

But however long it takes, there will eventually be a wave of used batteries whose performance is no longer deemed sufficient for vehicle use.  A new study, published in the journal Applied Energy, looked at the application of used vehicle batteries as backup storage for grid-scale solar photovoltaic installations where they could perform for more than a decade in this less demanding role.

The study looked at the economics of several scenarios including running a solar farm with no battery back up, running the same farm with brand-new batteries, and running the farm with a battery array made of repurposed vehicle batteries.

They found that the used EV battery array, if managed properly, could be a good, profitable investment provided that the batteries cost less than 60% of their original price.  They looked at the technical issues of screening batteries and combining batteries from different cars to work together.  They also looked at the economics of removing batteries from cars, collecting them, checking them over, and repackaging them.

Overall, they found that reusing vehicle batteries could ultimately meet half the forecasted demand for renewable energy backup storage over the next 10 years and would be both a technical and an economic success story.

**********

Web Links

Solar energy farms could offer second life for electric vehicle batteries

Photo, posted June 10, 2011, courtesy of Nick Ares via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Animals And Social Distancing | Earth Wise

By Leave a Comment

As the spread of COVID-19 continues throughout the U.S. and around the world, health officials continue to ask people to keep physical space between themselves and others outside their homes.  It’s an important and effective way to slow down and prevent the spread of disease. 

But it’s not just humans who can benefit from social distancing.  It turns out that animals can, too.

Microorganisms living on or inside our bodies are important for both our health and for the development of disease.  Researchers from the University of Texas at San Antonio have found evidence for the importance of social distancing to minimize the spread of microbes among individuals.   The researchers studied wild monkeys to find out what role diet, genetics, social groupings, and distance in a social network play when it comes to the microbes found inside the gut.  The gut microbiome refers to all the microorganisms living in the digestive tract. 

The research team studied the fecal matter of 45 female colobus monkeys that congregated in eight different social groups in a small forest in Ghana.  The researchers observed major differences in gut microbiomes between the eight social groups.  But individual monkeys from different groups that were more closely connected to the population’s social network had more similar gut microbiomes.  The findings, recently published in the journal Animal Behaviour, indicate that microbes may be transmitted between monkeys during occasional encounters with other monkeys from different social groups.

Learning how microorganisms pass among monkeys can help researchers understand how diseases spread.  Understanding how diseases spread can help guide decision making during this pandemic and any future disease outbreaks. 

**********

Web Links

Even animals benefit from social distance to prevent disease, research shows

Photo, posted January 10, 2007, courtesy of Silke Baron via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Extreme Heat And Humidity | Earth Wise

By Leave a Comment

On hot, sticky summer days, one often hears the expression “it’s not the heat, it’s the humidity.” That isn’t just an old saw; it is a recognition of what might be the most underestimated direct, local danger of climate change.   Extreme humid heat events represent a major health risk.

There is an index called “wet-bulb temperature” that is calculated from a combination of temperature and humidity data.  The reading, which is taken from a thermometer covered in a wet cloth, is related to how muggy it feels and indicates how effectively a person sheds heat by sweating.  When the wet-bulb temperature surpasses 95o Fahrenheit, evaporation of sweat is no longer enough for our bodies to regulate their internal temperature.  When people are exposed to these conditions for multiple hours, organ failure and death can result. 

Climate models project that combinations of heat and humidity could reach deadly thresholds for anyone spending several hours outdoors by the end of this century. 

Dangerous extremes only a few degrees below the human tolerance limits – including in parts of the southwestern and southeastern US – have more than doubled in frequency since 1979.  Since then, there have been more than 7,000 occurrences of wet-bulb temperatures above 88o, 250 above 91o, and multiple reading above 95o.  Even at lower wet-bulb temperatures around 80o, people with pre-existing health conditions, the elderly, as well as those performing strenuous outdoor labor and athletic activities, are at high risk.

More research is needed on the factors that generate extreme wet-bulb temperatures as well as the potential impacts on energy, food systems, and human security.

**********

Web Links

Dangerous Humid Heat Extremes Occurring Decades Before Expected

Photo, posted April 16, 2012, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tracking Locust Swarms | Earth Wise

By Leave a Comment

Plagues of locusts have been reported since the times of the Egyptian pharaohs.  In recent history, there have been desert locust plagues during multiple decades of the 20th century.  Since January, a very large population of locusts gathered in Kenya and has destroyed over 2,000 square miles of pasture and crop land.  Swarms have since reached portions of Ethiopia, Somalia, Uganda, and South Sudan.  Apart from East Africa, there are locust swarms in Yemen and other Middle East countries and in Pakistan as well.  The current situation continues to represent an unprecedented threat to food security and livelihoods in East Africa.  Locust swarms can range in size from less than half a square mile to hundreds of square miles, each containing 20 to 40 million locusts.

The National Oceanic and Atmospheric Administration uses a powerful air quality model to track the movement and deposition of pollution from wildfires, volcanoes and industrial accidents.  Called the HYSPLIT dispersion model, it has now been refined for the purpose of tracking swarms of locusts.

Because desert locusts are passive fliers that drift with the wind, the model’s high-quality data on wind speed and direction can lead to accurate predictions of where the locusts will go and when.

NOAA is working with the United Nations Food and Agriculture Organization – the FAO.  The new web application based on HYSPLIT is being used by the FAO to issue forecasts and warnings to affected countries about forthcoming waves of locust swarms.  Such forecasts enable local officials to conduct aerial spraying to reduce the impact of desert locusts which can destroy grains, grasses and other greens that are life-sustaining foods for entire regions.

**********

Web Links

NOAA teams with United Nations to create locust-tracking application

Photo, posted November 20, 2004, courtesy of Niv Singer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Keeping Charleston Dry | Earth Wise

By Leave a Comment

Charleston, South Carolina is visited by millions of tourists each year.  The town is a glimpse into the past, showcasing antebellum mansions, row houses, historic African American churches and scenic harbor views from a Civil War-era promenade.

Charleston is also visited more and more by water from rising seas and increasingly powerful storms.  The city is essentially drowning in slow motion and may soon face an existential threat to its survival.

Charleston has a harbor and three rivers and water from all these sources leaks in at every bend and curve, fills streets, disrupts businesses, and rushes into homes during storms.  Million-dollar antebellum mansions, built on spongy marsh and old tidal creeks, flood repeatedly.

City officials have endorsed a plan by the U.S. Army Corps of Engineers to wall off the historic downtown with an 8-mile-long seawall that would cost nearly $2 billion.  The proposed barricade is just one of many proposed projects to build seawalls, surge gates, levees, and other barriers to defend U.S. coastal cities in an era of rising seas and climate-fueled floods and storms.  A proposed flood wall in Miami would cost federal taxpayers $8 billion.

Researchers generally agree that sea levels are likely to rise by at least 3 feet by the end of the century.  Some experts believe the rise will be much greater.  So, a key question is whether these barriers will actually keep out the water.  Critics of many of the proposed solutions contend that they are doomed to fail.

Flooding has caused nearly $1 trillion worth of damage along the East and Gulf coasts over the past 40 years.  And things are almost certain to get worse in Charleston and other coastal cities.

**********

Web Links

Fortress Charleston: Will Walling Off the City Hold Back the Waters?

Photo, posted October 7, 2015, courtesy of Jeff Turner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Global Emissions And The Coronavirus Shutdown | Earth Wise

By Leave a Comment

With so much of industry and personal activity curtailed by coronavirus shutdowns across the globe, it is no surprise that greenhouse gas emissions have declined.  According to new research published in the journal Nature Climate Change, average daily global greenhouse gas emissions declined 17% by early April compared to 2019 levels.

If the reopenings around the world continue and the world actually reaches pre-crisis levels by the middle of June, total CO2 emissions for the year would likely end up lower by about 4%.   If various restrictions continue until the end of the year, total global emissions could decline by 7%.

The study analyzed emissions estimates for three levels of coronavirus shutdowns and across six sectors of the economy.  It looked at trends in 69 countries, all 50 U.S. states, and 30 Chinese provinces, representing in total 86% of the world’s population and 97% of global CO2 emissions.

For the first 4 months of the year, emissions from industry declined 19%, the power sector 7%, and public buildings and commerce 21%, compared to last year.  Unsurprisingly, home energy use actually went up by about 3%.

The findings of this study only represent the effects of a short-lived decline in emissions.  As economies open back up, there is no doubt that greenhouse gas emissions will rise back to pre-Covid-19 levels.

The study also reveals that making real changes in emissions will require more than just behavior changes.  Despite billions of people staying home, companies shut down, planes grounded, and cars off the road, we still managed to pump more than 80% of the usual amount of greenhouse gases into the air for the first quarter of the year.

**********

Web Links

Global Emissions Fell 17 Percent Due to Coronavirus Shutdowns

Photo, posted May 7, 2020, courtesy of the MTA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fighting Malaria With Gene-Drive Technology | Earth Wise

By Leave a Comment

Malaria continues to be a major health hazard throughout the tropical and subtropical regions of the world. There were 228 million cases of malaria in 2018 and over 400,000 deaths. 

Malaria is a mosquito-borne infectious disease spread by 40 of the world’s 3,500 mosquito species.  So, efforts to control mosquito populations are the primary strategy to eradicate malaria.

A team led by Imperial College London has created a genetic modification that distorts the sex ratio of a population of Anopheles gambiae mosquitoes using “gene drive” technology.  The modification works by using a DNA-cutting enzyme to destroy the X chromosome during the production of sperm, which leads to predominantly male offspring, since females require two X chromosomes.  The modification is coupled to a gene drive to allow it to spread through a population in a very effective way.  A gene drive is a genetic engineering technology that propagates a particular modification by assuring that a specific form of a gene (or allele) will be transmitted with far more than the natural 50% probability.

The result of this is that mosquitoes produce more male offspring, eventually leading to no females being born and a total collapse in the population. The mosquitoes studied are the main malaria vector in sub-Saharan Africa.  The hope is that mosquitoes carrying a sex-distorter gene drive would be released in the future, spreading the male bias with local malaria-carrying populations and causing them to collapse.  Only female mosquitoes bite and take blood meals.  If the gene drive technology works in the field, it could be a game-changer in the fight to eliminate malaria.

**********

Web Links

Malaria mosquitoes eliminated in lab by creating all-male populations

Photo, posted June 20, 2014, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Concrete Production And Diminishing Coal Burning | Earth Wise

By 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.

**********

Web Links

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

Photo, posted February 16, 2017, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)