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Permanent Time Observation | Earth Wise

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Americans have debated the value of daylight savings time going all the way back to Benjamin Franklin.  As a country, we adopted the practice of changing our clocks twice a year in 1918.

Since the energy crisis of the 1970s, there have been a number of initiatives aimed at making daylight savings time permanent.  However, there is also a growing movement to eliminate the practice entirely.

In August, the American Academy of Sleep Medicine published a position statement calling for the abolishing of daylight savings time in favor of fixed, national, year-round standard time.

The statement describes the adverse effects of the annual abrupt switch to daylight savings time, which range from increased risk of stroke and hospital admissions to sleep loss and increased production of inflammatory markers, which are one of the body’s responses to stress.  It also cites studies that show that traffic fatalities increase by as much as six percent in the first few days following the change to daylight savings time.  Other research shows that there is an 18% increase in adverse medical events related to human error in the week after switching to daylight savings time.

In July, a survey by the academy of more than 2,000 U.S. adults found that 63% support the elimination of seasonal time changes in favor of a national, fixed year-round time, and only 11% oppose the idea, but many of those in favor of the idea actually want permanent daylight savings time.

The sleep academy contends that permanent standard time is the best choice to most closely match our circadian sleep-wake cycle while daylight saving time results in more darkness in the morning and more light in the evening, disrupting the body’s natural rhythm.

Residents of Arizona and Hawaii get to sit out this debate since they don’t change their clocks.

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American Academy of Sleep Medicine calls for elimination of daylight saving time

Photo, posted May 28, 2018, courtesy of Kis Akos via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar On Commercial Buildings | Earth Wise

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The United States installed 3.6 gigawatts of photovoltaic solar capacity in the first quarter of this year to reach a total installed capacity of 81.4 GW.  That is enough to power about 16 million American homes.  More than 2/3 of that capacity has been installed during the past five years.  

There has been a boom in solar installations in recent years and, until the Covid-19 pandemic stuck, 2020 was expected to be the biggest year yet.  Now the unprecedented health, social, and economic conditions in our country creates great uncertainty in such forecasts.

Nevertheless, the opportunities for growth in solar power continue to be substantial.  A new report from the energy research firm Wood Mackenzie looked at the prospects for using the roof space of commercial buildings for solar power.

Currently, just 3.5% of commercial buildings in the U.S. have solar panels on their roofs.  Another 1% of those buildings are attached to solar projects located off-site.  The report looked at how many buildings are potential targets for solar projects.

After accounting for buildings that are too small or that use too little electricity to make solar power a worthwhile investment, the report estimated that 70% of commercial buildings in the U.S. – amounting to some 600,000 sites – are candidates for solar installations.  Doing this would provide 145 GW of new solar capacity, which is nearly twice as much as currently exists in this country. 

Commercial solar installations have their own unique logistical and financial challenges.  While utility solar can scale to lower costs and residential solar has financing opportunities, commercial solar has neither.  But ultimately, it represents an important opportunity for our future energy system.

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U.S. Commercial Rooftops Hold 145 Gigawatts of Untapped Solar Potential

Photo, posted June 25, 2014, courtesy of Rob Baxter via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Widespread Drought | Earth Wise

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As the U.S. enters the last part of the summer, fully one-third of the country is experiencing at least a moderate level of drought.   Much of the West is reaching severe drought conditions and New England has been unusually dry and hot.  In total, over 50 million Americans are living in drought-affected areas.

According to the U.S. Drought Monitor program, more than 93% of Utah, Colorado, Nevada, and New Mexico are experiencing drought to some degree.  More than 60% of both Utah and Colorado are in severe drought.   More than three-quarters of Oregon, Arizona, and Wyoming are also in drought.  And most of these areas had no sign of drought this time last year.

Severe drought conditions result in stunted and browning crops, limited pasture yields, dust storms, reduced well water levels, and an increase in the number and severity of wildfires.

Warm air temperatures and minimal snowfall in spring set the stage for this summer’s drought conditions.  A ridge of high pressure over the northeastern Pacific Ocean pushed the jet stream farther north than usual.  And, once again, there has been a failure of the southwestern monsoon in Arizona and New Mexico and the Four Corners region.  Monsoon rains provide half of the year’s precipitation in many of those areas. 

Instead, there has been extreme heat in the region.  Phoenix has already smashed the record for the most days over 110oF in a calendar year (42 as of August 18), with five months to go.  Las Vegas hasn’t seen measurable rainfall since April, and Cedar City, Utah has recorded a record low of 0.05 inches of rain this summer.

Conditions are not expected to get better for a couple of months.

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A Third of the U.S. Faces Drought

Photo, posted May 7, 2014, courtesy of Tyler Bell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Sharks On The Decline | Earth Wise

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During the past 70 years, global shark populations have been on the decline.   Many species have become threatened or endangered.  Conservation efforts have been underway in many places, but shark populations continue to be at risk because of over-fishing and habitat loss.

A comprehensive study by marine biologists at Texas A&M University deployed more than 15,000 baited remote underwater video stations on 371 coral reefs in 58 countries.   The study included 59 different shark species in the Atlantic, Pacific and Indian Oceans.  The researchers were surprised to find that no sharks at all were detected in almost 20% of the locations surveyed and were almost completely absent from coral reefs in several nations. 

Scientists believe that demand for shark products, such as fins and meat, and bycatch (that is, sharks captured in nets by fisherman trapping other kinds of fish) are strong contributors to the widespread declines in shark numbers around the world.

The study shows that if corrective steps are not taken in regions where marine management is still ineffective, continued depletion of shark populations is highly likely. 

Sharks have important roles in marine ecosystems.  When their habitats deteriorate and their populations decrease, ecosystem stability and health is degraded because sharks help regulate prey populations.

Some countries, notably the Bahamas, are combating the problem by providing sanctuaries for sharks where fishing and harvesting is prohibited.  Such places support some of the healthiest shark populations in the world.  However, the decline of coral reefs is just another challenge facing shark populations around the world.

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Study Shows Alarming Decline In Shark Numbers Around The World

Photo, posted January 9, 2017, courtesy of Kris-Mikael Krister via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Green Bills Pass In New York | Earth Wise

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In late July, the two houses of the New York legislature passed a number of environmental bills covering a wide range of topics.

These included a bill to add protected status for streams that support fisheries and non-contact recreation.  A second bill bans the use of PFAS in food packaging.  A third bill classifies all wastes resulting from oil and gas exploration, development, extraction or production as hazardous waste, closing a previous loophole in the law.

A fourth bill requires water works corporations with more than 1,000 service connections to post their annual water supply statements online, thereby providing transparency and openness to water quality data.  A fifth bill expands protections for endangered species to protect them from environmental rollbacks by the federal government.

A sixth bill prohibits non-electric vehicles from parking in spaces designated for electric vehicle charging, thereby establishing penalties for this practice that is often done for spite.  A seventh bill bans the use of glyphosate – the herbicide found in Roundup and other products – on state property.

An eighth bill reduces the use of road salt in the Adirondacks.  A ninth bill requires supermarkets to make good faith efforts to donate edible excess food to qualifying entities such as food pantries, food banks, or similar entities.   A tenth bill bans certain uses of trichloroethylene or TCE, including as a vapor degreaser, an intermediate chemical to produce other chemicals, a refrigerant, or an extraction solvent.

When signed by the governor, these ten pieces of legislation will help protect New York’s environment, water, and health.  It was a busy session for green legislation.

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Several Green Bills Pass in State Legislature

Photo, posted September 12, 2018, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Livestock Expansion And Global Pandemics | Earth Wise

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The domestication of cows, pigs, chickens, and other animals as livestock for their meat, milk, and eggs was historically revolutionary.  It boosted food security by giving people a readily-available means of feeding themselves as opposed to more traditional methods such as hunting and fishing. 

But animal agriculture has plenty of drawbacks.  The industrialization of animal agriculture has led to horrendous conditions.  Animals are kept in huge quantities and packed together with little regard for their health and welfare.  This approach to agriculture is simply designed to maximize production while minimizing costs. 

With its chemical inputs and toxic outputs, intensive animal agriculture is also a major threat to the environment.  In fact, it’s a major driver of habitat degradation and biodiversity loss all around the globe.   

But it’s not just animals and the planet that pay a price.  Humans have inherited several lethal pathogens from livestock over the years, including the influenza virus that likely jumped to humans from poultry.

According to a study recently published in Biological Conservation,  there is a connection between the global increase in the emergence of infectious diseases and epidemics, the accelerated loss of biodiversity, and the expansion of livestock.  In the study, the research team from the Institute of Evolution Sciences of Montpellier cross referenced databases on human and animal health, livestock expansion, and biodiversity loss between 1960-2019.  The team found that the number of epidemics identified in humans increased in correlation with both biodiversity loss and livestock expansion. 

In the era of COVID-19, it’s important to understand how global livestock expansion directly threatens both human health and the health of the planet. 

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Livestock expansion is a factor in global pandemics

Photo, posted July 22, 2018, courtesy of Artem Beliakin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Destroying Forever Chemicals | Earth Wise

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PFAS, short for poly and perfluoroalkyl substances, have been used in commercial products since the 1940s.  There are more than 4,000 different chemicals in the class.   Some of the most commonly used PFAS chemicals, like PFOS and PFOA, have long half-lives, which has earned them the moniker “forever chemicals.” 

These dangerous chemicals have not been manufactured in the U.S. since the early 2000s, but they can still be found in various imported goods.  PFAS chemicals have been linked to cancer, birth defects, thyroid disease, and liver damage.  These forever chemicals linger in the environment and scientists have found them in the blood of virtually all Americans.

Researchers at Rice University have recently discovered an efficient catalyst for destroying PFAS forever chemicals.  Unexpectedly, the catalyst was actually in the control group in a study they were performing.

The study, published in the journal Environmental Science and Technology Letters, found that boron nitride, acting as a light-activated catalyst, destroyed PFOA at a faster clip than any previously reported photocatalyst.

The catalyst, boron nitride powder, is a commercially available synthetic mineral that is widely used in makeup, skincare products, thermal pastes for cooling computer chips, and various other industrial products.  The discovery began with dozens of failed experiments on a variety of more promising PFAS catalysts.  But along the way, they found that the boron nitride control material repeatedly yielded positive results.

The research has already attracted the attention of industrial partners seeking to develop off-grid water treatment systems that both protect human lives and support sustainable economic development.

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Boron nitride destroys PFAS ‘forever’ chemicals PFOA, GenX

Photo, posted April 9, 2009, courtesy of Rex Roof via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Menace Of Abandoned Oil Wells | Earth Wise

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More than a century of oil and gas drilling has left behind millions of abandoned wells and many of them are leaching pollutants into the air and water.  Drilling companies continue to abandon even more wells as demand for oil diminishes and bankruptcies become more common.

Leaks from abandoned wells have long been known to be an environmental problem and a health hazard.  They have been linked to many instances of groundwater contamination and to dangerous fumes near homes and farms.

There have recently been efforts to track the amounts of methane leaching from abandoned oil and gas wells, and the figures in United States are alarming.  According to the most recent EPA report, more than 3.2 million abandoned oil and gas wells emitted a total of 281,000 tons of methane in 2018.  That is the climate-damage equivalent of consuming about 16 million barrels of crude oil, which is as much as the U.S. uses in a typical day.  According to the EPA, the actual amount could be as much as three times higher, because of incomplete data.   The agency believes that most of the methane comes from more than 2 million abandoned wells that were never properly plugged.

New York’s Department of Environmental Conservation has records of over 2,000 abandoned wells, but the state believes the actual number could be much higher.  This is a problem that won’t just go away.  Wells don’t leak for a year and then stop.  They can continue to leak for a century or more.  Cleaning up and plugging an abandoned well runs from $20,000 to $145,000, meaning that countrywide, cleaning up this environmental menace could cost somewhere between $60 billion and $435 billion.

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Special Report: Millions of abandoned oil wells are leaking methane, a climate menace

Photo, posted October 13, 2015, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Monitoring Wildlife For Warning Signs of the Next Pandemic | Earth Wise

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According to the World Health Organization, the coronavirus that causes COVID-19 likely originated in wild bats near Wuhan, China, and may have been passed to a second animal species before infecting people.  Since then, according to data from Johns Hopkins University, more than 13 million people around the world have been infected by COVID-19 and about 600,000 have died. 

But despite the ever-present threat of a new virus sparking the next pandemic, there is currently no global system to screen for viruses in wild animals that could eventually spill over to humans. 

In an article recently published in the journal Science, a group of scientists is calling for the creation of a decentralized global system of wildlife surveillance.  The establishment of this global system could help identify viruses in wild animals that have the potential to infect and sicken people before another global disease outbreak begins. 

According to the scientists, coronaviruses alone have caused outbreaks in humans three times in the last 20 years:  SARS (or Severe Acute Respiratory Syndrome), MERS (or Middle East Respiratory Syndrome), and COVID-19. 

While it’s impossible to know today how often viruses jump from animals to humans, human activity is making such spillover events more and more likely.  For instance, many continue to develop wild animal habitat to build new homes or businesses.  Some catch wild animals and re-sell them either for consumption or as exotic pets.  Parts from these wild animals are often shipped around the world as trinkets or as ingredients for traditional medicines. 

A global system that could identify potentially harmful viruses before they jump to humans is technologically feasible, affordable, and clearly necessary. 

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COVID-19 Dashboard by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University (JHU)

Global wildlife surveillance could provide early warning for next pandemic

Photo, posted January 15, 2008, courtesy of Doug Beckers via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Increasing Air Pollution | Earth Wise

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According to researchers from the University of Exeter, half of the world’s population is exposed to increasing air pollution despite global efforts to improve air quality.  The study, which was completed in conjunction with the World Health Organization, suggests that air pollution represents a major and growing threat to human health. 

For the study, which was recently published in the journal Climate and Atmospheric Science, the researchers reviewed global air quality trends between 2010 and 2016.  The research team examined those findings against a backdrop of global policies to reduce air pollution.  The researchers used ground monitoring data and satellite data to develop yearly air quality profiles for individual countries and regions. 

The scientists focused on fine particulate matter, which is a mixture of solid particles and liquid droplets found in the air.  Some of the particles, like dust, soot, or smoke, are large enough to be seen by the naked eye.  Others are so small that they can only be seen using a microscope.  Inhaling fine particulate matter can cause all sorts of health issues, including asthma, respiratory inflammation, and even promote cancer. 

For much of the world’s population, the consequences of polluted air are more deadly than war, violence, and many diseases.  According to the World Health Organization, more than four million deaths every year can be attributed to outdoor air pollution.  Some of the major sources of air pollution include coal-fired power plants, agriculture, transportation, and deforestation. 

The study found that low and middle income countries experience the highest burden of air pollution around the world, with the largest concentrations found in central and southeastern Asia.

More long term policies are needed to curb this growing threat to public health. 

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Half of the world’s population exposed to increasing air pollution

Photo, posted August 2, 2019, courtesy of Ron Reiring via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

More Troubles For Bees | Earth Wise

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Beekeepers in the United States lost nearly 44% of their managed honeybee colonies from April 2019 to April 2020, according to the 14th annual nationwide survey conducted by the nonprofit Bee Informed Partnership.  This was the second highest annual loss recorded since the surveys began.

The high loss rate over the past year was unusual in that winter losses were actually substantially lower than they have been in recent years.   The winter losses were 22.2%, which is 15.5 points lower than last year and 6.4 points lower than the average over the past 14 years.  On the other hand, summer losses were 32%, which is 12 points higher than last year and 10.4 points higher than the average.

In fact, the summer loss was the highest ever recorded and was only the second time that more bees were lost in the summer than in the winter.

Commercial beekeepers generally have lower losses than backyard and smaller operations.  Commercial honeybee colonies pollinate $15 billion worth of crops in the United States every year, so the health of these colonies is a critical issue for domestic food production and supply.

Beekeepers began noticing dramatic losses in their colonies in the early 2000s and ever since then, state and federal agricultural agencies, university researchers, and the beekeeping industry have been working together to try to understand the reasons for the population decline and to develop approaches to reduce these losses.

Winter loss has previously been the main focus of management activities since that period of the year is thought to be the most challenging for bee colonies.  This year’s results are driving a great deal of analysis of the possible causes for the dramatic summer colony losses.  Whatever they turn out to be, they represent more troubles for bees.

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Odd Year for U.S. Beekeepers Who Reported Lower Winter Losses but Abnormally High Summer Losses

Photo, posted April 14, 2013, courtesy of Paul Rollings via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Renewables Surpass Coal | Earth Wise

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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.

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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

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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.

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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.

Microplastics And Florida’s Birds of Prey | Earth Wise

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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. 

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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.

Animals And Social Distancing | Earth Wise

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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. 

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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

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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.

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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.

Fighting Malaria With Gene-Drive Technology | Earth Wise

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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.

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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.

Living In Extreme Heat | Earth Wise

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Global climate change has already left observable effects on the planet.  Glaciers have shrunk, trees are flowering sooner, plant and animal ranges have shifted, and so on. Many effects of climate change that scientists had predicted in the past are now occurring.  The loss of sea ice, intensifying heat waves, and accelerating sea level rise are some examples.

According to a new study recently published in the journal Proceedings of the National Academy of Sciences, climate change is going to affect humans earlier, harder, and more widely than previously projected.  The research team found that one billion people will be either displaced or endure insufferable heat for every one degree Celsius rise in global temperatures.  

Under a worst case climate scenario, land that one third of the world’s population currently calls home will be as hot as the hottest parts of the Sahara desert within 50 years.  Even under a more optimistic climate outlook, 1.2 billion people will still be exposed to temperatures outside the climate niche in which humans have thrived for at least 6,000 years.

The majority of the human population has always lived in regions where the average annual temperatures were between 43 degrees Fahrenheit and 82 degrees Fahrenheit.  These are ideal temperatures for human health and for food production.  But this temperature range is shrinking and shifting as a result of climate change. 

The study’s authors predict there will be more change in the next 50 years than there has been in the past 6,000 years.  They hope their findings will convince policymakers to accelerate their plans for emissions reductions and other climate mitigation strategies.   

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Future of the human climate niche

One billion people will live in insufferable heat within 50 years – study

Photo, posted November 22, 2008, courtesy of Ronnie Finger via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Shutting Down Pollution | Earth Wise

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With much of the country shut down as the coronavirus forces people to stay at home, there has naturally been a drastic reduction of traffic on roads and highways.   And with that decrease, there has been a dramatic reduction in pollution as well.

A satellite that detects emissions in the atmosphere linked to cars and trucks has observed huge declines in pollution in major metropolitan areas such as Los Angeles, Seattle, New York, Chicago, and Atlanta.

Los Angeles is infamous for its rush-hour traffic but that has pretty much ceased to exist. Similar changes can be seen in the San Francisco Bay Area, where nearly 7 million residents have been ordered to shelter in place.  New York City is less dependent on car travel than in other metro areas, but the shutdown of office buildings, schools, and restaurants has nonetheless resulted in a substantial reduction of traffic on the streets of the city.

While this sudden decline in air pollution over U.S. cities has some near-term health benefits, those benefits are likely to be fairly minor in the big picture.  When the coronavirus outbreak subsides and people are allowed to leave their homes and go back to their normal lives, air pollution will most certainly rebound to previous levels.  In any event, studies have shown that long-term exposure to air pollution has a larger impact on public health than any transient events.

Having much cleaner air for a while is certainly a good thing, but this shutdown is not a sustainable way to reduce air pollution and the long-term effects of the coronavirus crisis will certainly not be positive.

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Traffic and Pollution Plummet as U.S. Cities Shut Down for Coronavirus

Photo, posted March 15, 2020, courtesy of Tom Collins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Foods of the Future? | Earth Wise

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In a world where many go hungry in the context of rapidly changing environments, many experts contend that alternative food sources will be necessary to solve global food security problems.  So-called novel food sources are central to this conversation, defined as foods with no history of consumption in a region – or perhaps anywhere.

Three popular examples are lab-grown meat, insect farming, and seaweed aquaculture.  Each of these offer opportunities as well as challenges.

Lab-grown meat can refer to actual animal tissues raised in vats as well as the increasingly common cultured plant products made to resemble meat.  Lab-grown meat faces push back from the livestock industry that contends it should not be labeled as any kind of meat. While results to date are positive, barriers still remain including concerns over product taste, healthiness, and cost.  And while less land- and water-intensive than conventional livestock, cultured meat production is still energy intensive.

Insects do form a significant part of diets across the globe but have yet to be embraced in any substantial way in western cultures.  Nutritionally, numerous species of insects are rich in key proteins, micronutrients, and minerals.  But the “yuck factor” is a big barrier to cross.

Seaweed is a long-established part of many East Asian diets and has many potential dietary uses.  Several selectively bred varieties of seaweed supply a range of valuable nutrients.  Growing seaweed does not tax freshwater and terrestrial resources.  But intensively cultivated seaweeds would have potential negative effects on local marine ecosystems.

There is no single solution to complex issues like food security.  Novel foods may very well form part of the solution to a growing food crisis.

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Insects, seaweed and lab-grown meat could be the foods of the future

Photo, posted March 12, 2009, 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...)