death

What happened to the sea stars?

September 11, 2025 By EarthWise Leave a Comment

Billions of sea stars off the Pacific coast of North America from Mexico to Alaska have died from a wasting disease since 2013. This die-off is considered to be the largest ever marine epidemic. Over 90% of the population of sunflower sea stars has succumbed to the disease.

The result has been an explosion in the population of the sea urchins that the sea stars feed on. In turn, the sea urchins have devoured kelp forests that provide habitat for thousands of marine creatures. These kelp forests support a multi-million-dollar economy through fisheries and tourism as well as sequestering carbon dioxide and protecting vulnerable coastlines.

The disease begins with lesions and eventually kills sea stars by seemingly melting their tissues over a period of about two weeks. Sea stars with the disease become contorted and lose their arms.

For years, the definitive cause of the wasting disease has been elusive. But researchers from the University of British Columbia, the Hakai Institute, and the University of Washington have now identified a bacterium that is the disease-causing agent.

A strain of the Vibrio pectenicida bacteria – named FHCF-3 – is responsible. The Vibrio genus of bacteria includes pathogens that infect corals, shellfish, and even humans. Vibrio cholerae is the cause of cholera.

Research is now underway to understand the link between the disease and warming ocean temperatures due to climate change. The hope is that the discovery of the cause of the wasting disease will help guide management and recovery efforts for sea stars and impacted ecosystems.

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‘Disease detectives’ discover cause of sea star wasting disease that wiped out billions of sea stars

Photo, posted April 16, 2011, courtesy of Brian Gratwicke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Harmful algal blooms and climate change

September 5, 2025 By EarthWise Leave a Comment

An algal bloom is a rapid increase in the density of algae in an aquatic system. Harmful algal blooms occur when bodies of water get overloaded with nitrogen and phosphorus runoff from agriculture and other human activities. These excess nutrients can facilitate the out-of-control growth of cyanobacteria, also known as blue-green algae.

Some species of blue-green algae produce a toxin called microcystin. These toxins pose a serious health hazard to people, animals, and the environment. Microcystin affects liver function and can cause death in animals, as well as humans in rare instances. A notable incident occurred in the summer of 2014, when cyanobacteria contamination in Lake Erie left 500,000 residents in Ohio and Michigan without water for 72 hours and sickened more than 100 people.

According to a study led by researchers from Carnegie Science, as climate change warms the earth, higher-latitude regions will be at a greater risk for microcystin produced by algal blooms. The study found water temperatures of 68 to 77 degrees Fahrenheit as being at the greatest risk for developing dangerous levels of microcystin.

In the study, which was published in the journal Nature Water, the research team also demonstrated that the areas most susceptible to high toxin concentrations will continue to move northward. And in some areas, researchers say the relative risk of exceeding water quality guidelines will increase by up to 50% in the coming decades.

The research team hopes its findings raise more awareness about water sustainability, and the need to focus on the quality of the water as much as the quantity of water.

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Geographic redistribution of microcystin hotspots in response to climate warming

Photo, posted October 27, 2010, courtesy of Nara Souza / Florida Fish and Wildlife Commission via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wrong trees in the wrong places

January 20, 2025 By EarthWise Leave a Comment

Temperatures in cities are rising around the world and urban heat stress is already a major problem. Extensive surfaces of man-made materials absorb the sun’s energy, and lead to temperatures well above those in the surrounding countryside. This is known as the urban heat island effect, and it can lead to greater energy use, higher air pollution levels, and a greater risk of heat-related illnesses, as well as death.

Some cities have already started implementing mitigation strategies, with tree planting prominent among them. Planting trees can cool the climate by absorbing carbon dioxide, providing shade, and releasing water vapor, which lowers air and surface temperatures.

However, while trees can cool cities significantly during the day, new research from the University of Cambridge in the U.K. shows that tree canopies can also trap heat and raise temperatures at night.

According to the study, which was recently published in the journal Communications Earth & Environment, planting the wrong species or the wrong combination of trees in suboptimal locations or arrangements can limit their benefits.

The researchers found that in temperate climates, trees can cool cities by up to 6°C during the day but can increase nighttime temperatures by 1.5°C. Cities with open layouts in temperate and tropical climates benefit from a mix of evergreen and deciduous trees, enhancing cooling by 0.5°C more than in cities with only deciduous or evergreen trees.

The researchers hope their findings will help urban planners choose the best combinations of trees and planting locations to combat urban heat stress.

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Wrong trees in the wrong place can make cities hotter at night, study reveals

Photo, posted October 29, 2017, courtesy of Lars Plougmann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Corals and climate change

December 24, 2024 By EarthWise Leave a Comment

Climate change is a major threat to coral reefs around the world. Ocean warming triggers coral bleaching – a stress response where corals expel the symbiotic algae essential for their survival. If coral bleaching is severe, it can lead to coral death.

A new study led by scientists from Newcastle University in England suggests that corals are unlikely to adapt to ocean warming quickly enough to keep pace with global warming, unless there are rapid reductions in global greenhouse gas emissions.

The study, which was recently published in the journal Science, found that coral heat tolerance adaptation via natural selection could keep pace with ocean warming, but only if the climate goals of the Paris Agreement are realized. In the Paris Agreement, countries agreed to limit global warming by the end of the century to two degrees Celsius above pre-industrial levels.

However, current climate policies around the world have the globe on track to warm by three degrees Celsius. According to the research team, this could lead to significant reductions in reef health, elevated risks of local coral extinctions, and considerable uncertainty in the so-called “evolvability” of corals.

Coral reefs are among the most biologically diverse ecosystems on Earth. They are often referred to as the “rainforests of the sea” because they support an incredible variety of marine life. They provide essential ecosystem services, such as protecting coastlines from erosion and storm surges, supporting fisheries, and serving as a source of income through tourism. Coral reef health is vital for the health of the planet.

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Coral adaptation unlikely to keep pace with global warming

Photo, posted June 9, 2012, courtesy of Bokissa Private Island Resort via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Pollution in downwind states

August 26, 2024 By EarthWise Leave a Comment

Air pollution is a serious health threat. It is associated with asthma and can lead to chronic disease, cancer, and premature death. Globally, air pollution kills 7 to 9 million people, and 200,000 Americans die from it each year.

There are multiple sources of air pollution including automobiles, power plants, and other industrial activities. Exposure to pollutants such as nitrogen oxide, sulfur dioxide, and particulate matter does not require living or working near their sources. Winds can carry pollution great distances including across state lines.

The Clean Air Act included the EPA’s “Good Neighbor Plan”, which requires “upwind” states to implement plans to reduce emissions from power plants and other industrial sources. However, three states – Indiana, Ohio, and West Virginia – along with various industrial companies and trade organizations sued the EPA when it tried to enforce these plans. A recent Supreme Court decision to block a federal rule curbing interstate air pollution further complicates efforts to reduce emissions.

As a result, there is a disproportionate burden on downwind states. They face major challenges in demonstrating and attributing air pollution to sources across state lines and pursuing legal actions to get the EPA to address their problems.

A recent study by the University of Notre Dame looking at all the complex issues related to interstate pollution underscored how the regulatory system continues to be hamstrung when attempting to address a serious threat to human health and the environment.

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Downwind states face disproportionate burden of air pollution

Photo, posted February 19, 2021, courtesy of David Wilson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Air pollution in India

February 19, 2024 By EarthWise Leave a Comment

India is one of the world’s most polluted countries. In fact, of the 30 cities with the worst air pollution around the globe, 21 of them can be found in India.

India’s capital city, New Delhi, is the most polluted city in the world. Concentrations of fine particulate matter (known as PM2.5) in Delhi, which is the name of the larger city that includes the capital New Delhi, are nearly 10 times greater than the World Health Organization guidelines.

To reduce air pollution in Delhi, officials have focused on measures within the city limits, including boosting public transportation and regulating pollution from industry.

But according to a review carried out by the University of Surrey and regional government officials in Delhi, the city will also need the help of its neighbors to tackle its killer smog problem. Some of the pollution plaguing Delhi comes from rural areas in the region – from things like crop burning, wood stoves, and power plants. The review, which was part of a paper recently published in the journal Sustainable Horizons, also recommends drafting regional air quality plans, producing smog forecasts, and creating airshed councils to help improve coordination.

Exposure to air pollution can cause all sorts of major health problems, including asthma, respiratory inflammation, as well as jeopardize lung function, and even promote cancer. Long-term exposure to PM2.5 is linked to premature death. In fact, air pollution causes an estimated 670,000 deaths every year in India.

Since air pollution doesn’t respect boundaries or borders, solutions require collaboration and the need to focus efforts more broadly in order to achieve emissions reduction goals.

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Delhi smog: India’s cities must look beyond their limits to clean up air pollution

Photo, posted December 27, 2019, courtesy of Ninara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Action on the toxic chemical from tires

December 13, 2023 By EarthWise Leave a Comment

Since the 1990s, populations of coho salmon in streams and urban creeks up and down the West Coast have been dying in large numbers. Scientists at the University of Washington began studying the mysterious deaths and it took years to figure out what was going on. They analyzed water samples from urban creeks and found that chemicals from vehicle tires were present. By soaking tires in water, they found that more than 2,000 chemicals were present. It took three years to narrow down the suspect list to one chemical: a toxin called 6PPD-quinone, which is produced when the common tire preservative 6PPD mixes with oxygen. It is that chemical that was responsible for the salmon die-off.

6PPD-quinone is toxic enough to quickly kill some fish. Studies showed that concentrations of the chemical in stormwater were found to be lethal for coho salmon following exposures lasting only a few hours.

Despite the discovery, the tire industry has continued to use the chemical in its products. The industry says 6PPD is an antioxidant and antiozonant that helps prevent degradation and cracking of tires in the environment and is essential for the performance and safety of vehicles.

Last year, California regulators directed the tire industry to seek out substitutes for 6PPD. The U.S. Tire Manufacturers Association pledged to investigate possible safer alternatives to the chemical.

In November, spurred by a petition by West Coast tribes whose lifeways depend on coho salmon, the EPA said it will study the impact of 6PPD with an eye to potentially banning its use.

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After Salmon Deaths, EPA Takes Aim at Toxic Chemical Issuing from Car Tires

Photo, posted May 31, 2021, courtesy of Chris Yarzab via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Vaccine For Bees | Earth Wise

February 27, 2023 By EarthWise Leave a Comment

The US has seen annual reductions in honey bee colonies since 2006. According to the USDA, there are many factors that have contributed to the decline. These include parasites, pests, insecticides, disease, and a phenomenon called Colony Collapse Disorder in which worker bees abandon a hive and leave behind the queen.

One of major threats to bee colonies is American foulbrood disease, which is a bacterial condition that attacks bee larvae. It is highly contagious and has no cure. Until now, the only treatment method required burning the colony of infected bees along with the hives and equipment and treating nearby bee colonies with antibiotics.

Recently, the USDA has approved a conditional license for the world’s first vaccine for honey bees. The vaccine contains inactive bacteria of the type that causes American foulbrood disease.

The vaccine is incorporated into the royal jelly fed by worker bees to the queen bee. The queen ingests the feed and keeps some of vaccine in her ovaries. This gives bee larvae immunity to the disease as they hatch and thereby reduces death from the illness.

According to the California State Beekeepers Association, the new vaccine could be a major breakthrough for protecting bees. Preventing the infection in hives could avoid costly, destructive measures and allow the beekeepers to focus on other important elements of keeping bees healthy.

Bees as pollinators play a critical role in many ecosystems. For humankind, pollinators such as bees, birds, and bats are responsible for about a third of the world’s crop production.

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US approves world’s first vaccine for declining honey bees

Photo, posted June 6, 2022, courtesy of Bernd Thaller via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Importance Of Wildlife Crossings | Earth Wise

September 23, 2022 By EarthWise Leave a Comment

Highway accidents involving animals are a big problem for both people and animals. According to the National Highway Traffic Safety Administration, motorists in the United States kill one to two million large animals every year. About 200 people are killed annually in the U.S. as a result of those collisions with animals.

These crashes are expensive, too. Deer-vehicle collisions cost an average of more than $8,000 each; elk-vehicle collisions cost about $25,000; and moose-vehicle collisions cost more than $44,000.

One solution that has been quite effective around the world in reducing car-animal collisions is wildlife overpasses and underpasses. They are designed to help animals move in search of food and to escape predators and wildfires. These traffic-spanning bridges and tunnels have been popular in Europe since the 1950s. They look much like regular overpasses for cars but are decked out with native flora. The underpasses, which assist shyer and smaller animals, are typically invisible to drivers.

According to a new economic analysis by researchers at Washington State University, wildlife crossings in Washington State save roughly $235,000 to $443,000 every year per structure.

Wildlife crossing structures range in cost from $500,000 for a tunnel-like underpass to more than $6 million for a broad bridge. There may soon be many more wildlife crossing structures across the country since $350 million was allotted in the federal Infrastructure Investment and Jobs Act signed into law in 2021.

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Wildlife crossings potentially save millions annually in Washington state

How wildlife bridges over highways make animals—and people—safer

Photo, posted March 24, 2017, courtesy of Jeffrey Beall via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Hot July | Earth Wise

August 24, 2022 By EarthWise Leave a Comment

At the beginning of July, the National Oceanic and Atmospheric Administration’s monthly climate outlook predicted temperatures well above average across much of the United States. The prediction was quite correct. Beyond that, world-wide, there were multiple heat waves, especially in Europe and Asia, where there were thousands of heat-related deaths. On July 19th, the United Kingdom had its hottest day ever reported with a temperature over 104 degrees.

In the U.S., a series of atmospheric high-pressure systems resulted in stagnant heat domes, which resulted in more than 150 million people living under heat warnings and advisories. Nearly every part of the continental U.S. saw above-average temperatures. There were record-breaking triple-digit highs in several states, sometimes persisting for days.

The south-central part of the country developed a ridge of high pressure that established a heat dome that acted like a lid, trapping hot air over that area. The extreme heat persisted throughout the month, at times expanding to the Southwest, Upper Midwest, and Southeast.

In the second half of the month, the Great Plains experienced temperatures as high as 115 degrees. Utah and Oklahoma both broke long-standing records for the most consecutive days on which temperatures exceeded 100 degrees. Utah saw 16 straight days over 100.

In the Pacific Northwest temperatures reached 110 degrees in Dallasport, Washington, and 114 in Medford, Oregon. In the Northeast, Newark, New Jersey saw a record-breaking five straight days over 100 degrees.

In Albany, New York, where the average daily high temperature is 82 degrees in July, there were 10 days in the 90s, with highs of 97 on three occasions.

July was a hot month indeed.

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A July of Extremes

Photo, posted July 10, 2022, courtesy of Dominic Alves 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

Photo, posted February 13, 2010, courtesy of Steve Snodgrass via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Deadly Urban Heat On The Rise | Earth Wise

November 9, 2021 By EarthWise Leave a Comment

According to a new study by the Columbia Climate School, exposure to deadly urban heat has tripled since the 1980s. The increase is the combined result of both rising global temperatures and booming urban population growth.

The study looked at more than 13,000 cities worldwide and found that incidents of extreme heat and humidity have increased dramatically. It defined extreme heat as 30 degrees Celsius on the wet-bulb temperature scale that takes into account the effect of high humidity. In 1983, there were 40 billion person-days under such conditions. By 2016, the number was 119 billion. More specifically, in 2016 1.7 billion people were subjected to such conditions on multiple days.

Sheer urban population growth accounted for two-thirds of the increase, while actual warming contributed a third. Over recent decades, hundreds of millions of people have moved from rural areas to cities, which now hold more than half the world’s population. And because of the urban heat island effect, temperatures in cities are generally higher than in the countryside.

In the United States, about 40 sizable cities have seen rapidly growing exposure to extreme heat, mainly clustered in Texas and the Gulf Coast. Globally, nearly a quarter of the world’s population is affected by the increased incidence of extreme temperatures.

A study last year showed that combinations of heat and humidity literally beyond the limits of outdoor human survival have been popping up around the world. A wet-bulb temperature reading of 30 – equivalent to 106 degrees Fahrenheit on the “real feel” heat index – is the point at which even most healthy people find it hard to function outside for long, and the unhealthy might become very ill or even die.

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Exposure to Deadly Urban Heat Worldwide Has Tripled in Recent Decades, Says Study

Photo, posted March 5, 2007, courtesy of Michael Phillips via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Lead Exposure Remains A Persistent Problem | Earth Wise

October 29, 2020 By EarthWise Leave a Comment

According to a new report from UNICEF and the international nonprofit Pure Earth, a staggering number of children – approximately 800 million or one out of every three globally – may have dangerously high levels of lead in their blood.

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. The most common symptom of lead poisoning is lethargy. Lead exposure can also contribute to a lower IQ and behavioral problems that can last a lifetime.

According to the report, much of the lead poisoning comes from lead-acid batteries that are not properly recycled. Water pipes, paint, canned foods, makeup, toys, and even contaminated spices can all be sources of lead exposure. Lead was also previously added to gasoline and traces of this remain in soil samples today.

The report found that children in low- or middle-income countries, especially in South Asia and among marginalized groups in general, are most vulnerable to lead poisoning.

Lead exposure remains a dangerous and persistent problem all around the world.

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The Toxic Truth: Children’s Exposure to Lead Pollution Undermines a Generation of Future Potential

800 million children still exposed to lead

Photo, posted February 11, 2017, courtesy of J. Brew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Extreme Heat And Humidity | Earth Wise

June 15, 2020 By EarthWise 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 95^o 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 88^o, 250 above 91^o, and multiple reading above 95^o. Even at lower wet-bulb temperatures around 80^o, 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.

Environmental Injustice And the Coronavirus | Earth Wise

May 29, 2020 By EarthWise Leave a Comment

Cities and towns across the United States continue to wrestle with the devastating impacts of the COVID-19 pandemic and none have been hit harder than low-income and minority communities. Places like Detroit, Chicago, and St. James Parish in Louisiana have suffered from decades of economic inequality and pollution in their poorest neighborhoods and many of these same places have experienced some of the highest mortality rates from the virus.

Recent studies have shown a link between high levels of pollution and the risk of death from COVID-19. Pollution of various kinds are higher in low-income communities and communities of color. Such communities don’t have a strong political voice so that laws and environmental regulations are not enforced like there are in white, higher-income communities. Thus, these communities have highways, landfills, factories, chemical facilities, paper mills, and other pollution sources that communities with economic power – and therefore political power – manage to avoid.

People living in low-income communities and communities of color tend to have higher rates of underlying health conditions like diabetes, heart disease, and asthma. They have less healthy diets – more fast food and fewer grocery stores. Part of the reason these communities have a higher risk of mortality from COVID-19 infection is that many people have reduced lung capacity as a result of exposure to pollutants.

The Trump administration has been suspending enforcement of environmental regulations during the pandemic. Communities already affected by environmental injustice will bear the brunt of this decision. Groups like nursing home populations, meat packers, prisoners and the poor are suddenly highly visible. COVID-19 is exposing the real differences between the Haves and the Have-Nots in this country.

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Connecting the Dots Between Environmental Injustice and the Coronavirus

Photo, posted May 2, 2006, courtesy of Sean Benham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Lockdown Cleans Up Indian Air | Earth Wise

May 13, 2020 By EarthWise Leave a Comment

Our stories often discuss how human activities change the natural environment. With most of us confined to our homes, the lack of human activities is having profound effects on the environment. We are talking about some of these this week.

India suffers from some of the worst air pollution in the world. Of the most polluted cities in the world, 21 out of 30 were in India in 2019. According to World Health Organization standards, at least 140 million people in India breathe air containing 10 times or more greater levels than the safe limit for pollutants. Air pollution contributes to the premature death of 2 million Indians every year.

Half of India’s air pollution comes from industry, 27% from vehicles, and 17% from crop burning. Crop burning is prevalent because it is much cheaper than mechanical tilling after the harvest.

On March 25, the Indian government placed its 1.3 billion citizens under a strict lockdown to reduce the spread of COVID-19. The country-wide mandate decreased activity at factories and drastically reduced car, bus, truck, and airplane traffic.

Within one week, NASA satellite sensor observed aerosol levels at a 20-year low for this time of year in northern India. Aerosols are tiny solid and liquid particles suspended in the air that reduce visibility and can damage the human lungs and heart. Some aerosols have natural sources, such as dust storms, volcanic eruptions, and forest fires. But many come from human activities such as the burning of fossil fuels and croplands. Scientists expected to see changes in atmospheric conditions during the Indian lockdown, but the current changes are dramatic. They also present a unique opportunity to separate how natural and human sources of aerosols affect the atmosphere.

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Airborne Particle Levels Plummet in Northern India

Photo, posted April 29, 2020, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wildlife Bridges

June 17, 2019 By EarthWise Leave a Comment

Highway accidents involving animals are a big problem for both people and animals. About 200 people die every year in the U.S. as a result of collisions with animals. In total, one to two million large animals are killed by motorists every year. And these crashes are expensive: deer-car collisions cost an average of more than $8,000 each; elk-vehicle collisions about $25,000; and moose-vehicle collisions over $44,000.

In the United States, there are 21 threatened and endangered species whose very survival is threatened by road mortalities. These include Key deer in Florida, bighorn sheep in California, and red-bellied turtles in Alabama.

One solution that has been quite effective around the world in reducing car-animal collisions is wildlife overpasses and underpasses. Crossings and fencing that guide animals over or under highways reduce collisions by 85-95%.

These traffic-spanning bridges and tunnels have been popular in Europe since the 1950s. The overpasses usually look much like regular overpasses for cars but are decked out with native flora. The underpasses, which assist shyer and smaller animals, are typically invisible to drivers.

Washington State has recently started building wildlife bridges and underpasses on Interstate 90. These passes will allow elk, black bears, mountain lions, pika, and even trout to traverse what was once a near-impenetrable barrier of road.

Some animals that are accustomed to human structures start using the crossings almost immediately. For others, there is learning curve. As in many things, the early adapters are important as they provide paths and model behavior that more reticent animals learn to follow.

Wildlife bridges are a very good thing for wildlife and for people.

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