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Lakes Are Shrinking | Earth Wise

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A study by the University of Colorado Boulder has found that more than half of the world’s largest lakes have shrunk over the last three decades.  This is a very big problem because about one-quarter of the Earth’s population lives in the basin of a drying lake.  People depend on lakes for drinking water and irrigation and lakes are central to the survival of local ecosystems as well as migrating birds.  Lakes cover only about 3% of the planet, but they hold nearly 90% of the liquid surface freshwater.

The study used satellite observations from 1992 to 2020 to estimate the area and water levels of nearly 2,000 freshwater bodies.  These account for 96% of Earth’s total natural lake storage and 83% of that in man-made reservoirs.  About 53% of the world’s lakes have clearly shrunk, while only 22% have gained water.  The study estimates that about 160 trillion gallons of water has been lost over the 28-year period.  That’s about 17 times the maximum capacity of Lake Mead, the largest reservoir in the United States.

Many of the world’s most significant lakes have been shrinking. The dramatic declines in Lake Mead have been headline news for years.  The Caspian Sea, which is the world’s largest inland body of water – has long been declining.

The main causes of the decline in natural lakes are climate change and human consumption.  Reservoirs face an additional major problem of sediment buildup which reduces their storage capacity and diminishes their benefits of water supply, flood control, and hydropower.

Lake loss is a big problem.

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More than half of the world’s largest lakes are drying up

Photo, posted April 10, 2018, courtesy of Ninara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Air Pollution And Insects | Earth Wise

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Insects can be found in every environment on Earth and play critical roles in the planet’s ecosystems.  Insects pollinate more than 80% of plants, including those that we eat and those that provide food and habitat for other species.  Without insects, we wouldn’t have the rich biodiversity that supports life on earth today.

But the world is experiencing a decline in overall insect populations as well as a collapse in insect diversity.  According to researchers from the University of Melbourne in Australia, Beijing Forestry University in China, and the University of California – Davis, air pollution particles may be the cause of the dramatic decline.  They found that an insect’s ability to find food and a mate is reduced when their antennae are contaminated by particulate matter. 

In the study, which was recently published in the journal Nature Communications, the research team exposed houseflies to varying levels of air pollution for just 12 hours and then placed the flies in a Y-shaped tube ‘maze’. Uncontaminated flies typically chose the arm of the Y-maze leading to a smell of food or sex pheromones, while contaminated flies selected an arm at random, with 50:50 probability.

Using a scanning electron microscope, the researchers also found that as air pollution increases, more particulate material collects on the sensitive antennae of houseflies. 

Insect antennae have olfactory receptors that detect odor molecules emanating from a food source, a potential mate, or a good place to lay eggs.  If an insect’s antennae are covered in particulate matter, a physical barrier is created between the smell receptors and air-borne odor molecules.

Air pollution poses a significant threat to insect populations around the world.   

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Air pollution particles may be cause of dramatic drop in global insect numbers

Photo, posted June 13, 2008, courtesy of Allen Watkin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Missing Antarctic Sea Ice | Earth Wise

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It is summer here in the United States, but it is winter in Antarctica.  Antarctic sea ice is water that forms and melts entirely in the ocean and it has a pattern of growth and reduction that has been monitored by satellites for the past 44 years.  The area of sea ice that surrounds the continent of Antarctica is known as the sea ice ‘extent’ and it had been quite stable for much of those years.

In 2016, the sea ice extent began to decline.  Since then, there have been several record summer lows with both the summers of 2021/22 and 2022/23 setting new minimum records.

This August, the deviation from all previous records intensified.  This winter’s sea ice extent is over 900,000 square miles below the long-term average, an area about the size of Greenland or, for example, Texas and Alaska combined.

Climate models have long predicted that Antarctic sea ice would reduce as a result of global warming but the current change to sea-ice extent is so dramatic that it is difficult to explain.  Sea ice extent is affected by multiple factors including the El Niño Southern Oscillation, the strength of the southern hemisphere jet stream, and regional low-pressure systems.  The warming climate is certainly the overall force that is changing Antarctic sea ice extent over time.

Antarctic sea ice extent is important because it covers a vast area of the dark Southern Sea with a bright white surface that reflects the sun’s energy back into space, helping to reduce temperatures at the pole and protecting glaciers and polar ice sheets. 

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The mystery of the missing Antarctic sea ice

Photo, posted November 7, 2016, courtesy of Rob Oo via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

How To Support Pollinators | Earth Wise

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Pollinators of all sorts have been in decline for a while.  This is especially true of bees, bats, and monarch butterflies.  Without pollinators, fruits, vegetables, and other plants cannot provide their contributions to our food supply.  According to experts, about 30% of the food that ends up on our tables gets there because of pollinators.

Bees are the most efficient pollinators, but plenty of other insects do their share as well.  Butterflies and months, flies, beetles, and wasps all are good pollinators.  In addition to insects, birds and bats can also be pollinators. 

Entomologists at Texas A&M University have offered some science-based advice for homeowners who want to keep pollinators around and thriving during the summer months.

Pollinators need flowers that bloom at different times of the year.  So, home gardens should overlap blooms.  Native and drought-tolerant species are good additions to a garden or landscape.

Colorful gardens attract more pollinators because different pollinators are attracted to different colors.  Bumblebees like blues and purples; other bees are attracted to yellows and whites.  Butterflies like bright colors like oranges and pinks.

Plant flowers with different shapes and sizes because pollinators flower preferences come in all shapes and sizes.

Provide shelter for pollinators.  Houses for bees and other pollinators are available for purchase. Or people can make their own using plastic tubes.

And probably most importantly, go easy on pesticides.  If it is really necessary to apply pesticides, do it in the evening when most pollinators have called it a day.

Having a colorful garden with lots of variety is a fine addition to one’s home.  Beyond that, it is a valuable contribution to helping preserve essential pollinators.

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Top Five Tips For Supporting Pollinators This Summer

Photo, posted August 14, 2017, courtesy of USFWS Midwest Region via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wind And Solar Pass Coal | Earth Wise

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For the first five months of this year, wind and solar generated more electricity than coal in the United States.  This is a first.  Total renewable energy generation exceeded coal-fired power in both 2020 and 2022, but that counted hydroelectric power as one of the renewable sources.

This year, wind and solar alone generated a total of 252 terawatt-hours of energy through May compared with coal’s output of 249 terawatt-hours.  Hydropower generated an additional 117 terawatt-hours during that period.

While solar and wind power have been expanding at a rapid rate, the biggest change this year has been a precipitous drop in coal-fired generation due to a combination of low natural gas prices, a mild winter, and a series of coal plant retirements.

Coal generated almost half of the country’s electricity as recently as 2008.  Since then, coal has steadily declined as older coal plants shut down and were replaced by natural gas plants and renewable energy sources.  The coal industry had a bit of a reprieve last year when natural gas prices spiked in response to the disruptions in gas supplies in Europe due to the war in Ukraine.  The benchmark for natural gas prices – known as Henry Hub – was $8.81 in August 2022.  In May of this year, it was $2.15.  Given this trend, the demand for coal has steadily declined. 

The US has retired another 7% of the coal fleet – 14 gigawatts of capacity – since the start of 2022.  Meanwhile, power companies have added 22.5 GW of wind and solar capacity in just the past 12 months.

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In a First, Wind and Solar Generated More Power Than Coal in U.S.

Photo, posted September 20, 2016, courtesy of Bureau of Land Management via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Cryo Conservation | Earth Wise

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Recent studies have shown that there has been a 69% decline in global animal populations since 1970.  There is a biodiversity crisis in the world.  In the face of this situation, there is a growing interest in using cold storage to preserve genetic samples taken from animals threatened with extinction.

Just as egg-freezing is used to preserve human fertility for a later date, the cryogenic freezing of genetic material from animals could be important in reducing species extinctions.  Living cell banks – also known as cryobanks – could preserve genetic materials from animals that include skin cells, embryos, semen, and live tissues.  These materials could be cultured and used for various applications including DNA extraction, assisted reproduction, ensuring genetic diversity in animal populations, and potentially reintroducing species back into their natural habitats.

There is a facility called the Frozen Zoo at the San Diego Wildlife Alliance which has genetic material from 965 different species, including 5% of the vertebrates currently listed as threatened on the IUCN Red List.  Further sampling from zoos and aquariums could increase that representation to almost 17%.

Genetic samples of 50% of the species currently listed as extinct in the wild are already represented in the Frozen Zoo.  Further sampling from the zoological community could increase this number to 91%.  This could provide a critical lifeline for these species that are on the brink of extinction.  As wildlife populations continue to decline around the world, it is more critical than ever to collect and preserve genetic samples from threatened species.

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Cryo conservation – a cool solution to saving species from extinction

Photo, posted September 30, 2018, courtesy of Andy Morffew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Ocean Oxygen Levels And The Future Of Fish | Earth Wise

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Climate change is creating a cascade of effects in the world’s oceans.  Not only are ocean temperatures on the rise, but oceans are becoming more acidic, and oxygen deprived.  The warming temperatures and acidification have grabbed headlines and prompted academic research. Declining oxygen levels have not garnered as much attention.  But they spell bad news for fish.

Oxygen levels in the world’s oceans have dropped over 2% between 1960 and 2010 and are expected to decline up to 7% over the next century.  There are places in the northeast Pacific that have lost more than 15% of their oxygen.  There are a growing number of “oxygen minimum zones” where big fish cannot survive but jellyfish can.

Oceans are losing oxygen for several reasons.  First, warmer water can hold less dissolved gas than colder water.  (This is why warm soda is flatter than cold soda.)  Deeper in the ocean, oxygen levels are governed by currents that mix oxygen-rich surface water from above.  Melting ice in the warming polar regions add fresh, less-dense water that resists downward mixing in key regions.  Finally, increasing amounts of ocean bacteria in warming waters gobble up oxygen creating dead zones in the ocean.

In many places, fish species that cannot cope with lower oxygen levels are migrating from their usual homes, resulting in a decline in species diversity.  Our future oceans – warmer and oxygen-deprived – will not only hold fewer kinds of fish, but also smaller fish and even more greenhouse-gas producing bacteria.   

Climate change is bad news for fish and for the more than 3 billion people in the world who depend on seafood as a significant source of protein.

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As Ocean Oxygen Levels Dip, Fish Face an Uncertain Future

Photo, posted January 10, 2022, courtesy of Willy Goldsmith via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Can All Plant Species Survive? | Earth Wise 

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Many animal populations around the world are struggling and people are mostly to blame.  Species are declining because of all sorts of things including changes in land and sea use, pollution, invasive species, and climate change.

Like many animal species, plants are also struggling to adapt to a human-dominated world.  Plants provide the planet with food, oxygen, and energy, and are used to produce fibers, building materials, and medicines.  Even though plants are easier and cheaper to protect, they are often overlooked in conservation efforts. 

According to a paper recently published in the journal Trends in Plant Science, preventing all future land plant extinctions across the globe is possible with the right approaches.  The author of the paper, Richard Corlett of the Xishuangbanna Tropical Botanical Garden in China, writes that “if zero extinction is potentially achievable for plants, a less ambitious target would be inexcusable.” 

According to the paper, one big barrier in plant conservation is the lack of trained specialists, especially in tropical areas where there is a backlog of unidentified species.  It’s likely that many “dark extinctions,” which is when species slip away without us knowing they existed, have already occurred.

Another roadblock in preventing plant extinctions is information access, which can be solved by building an online “metaherbarium.”  This collaborative database would link digitized records from herbarium specimens with photographs, status assessments, and recovery plans.

Finally, the creation of “microreserves” – which are tiny pieces of protected land designed to get around space constraints – would further contribute to effective conservation of targeted plant species. 

Zero plant extinctions should be the goal.   

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‘Zero plant extinction’ is possible, says plant ecologist

Photo, posted May 16, 2008, courtesy of Andrew Otto via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Falling Lithium Prices | Earth Wise

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Lithium, the key element in the batteries that power electric cars, as well as smartphones, tablets, and laptop computers, is sometimes called white gold.  Over time, the price of the metal has gone up and up.  But recently, and surprisingly, the price of lithium has actually gone down, helping to make electric vehicles more affordable.

Over the first couple of months of this year, the price of lithium has dropped by nearly 20%.  The price of cobalt, another important component of vehicle batteries, has fallen by more than half.  Even copper, another battery material, has seen its price drop by 18%.

Many analysts predicted that prices of these commodities would stay high or even climb higher.  The reason for the decline, as well as whether it is likely to persist, is the subject of much debate.

Some experts believe that the price drops are a result of demand not being as high as expected, perhaps related to slowing sales growth of EVs in Europe and China after certain subsidies expired.  Other industry experts said that the drop was a result of new mines and processing plants providing additional supply sooner than was thought possible.

Despite the price drops, mining and processing lithium remains an extraordinarily profitable business.  It costs from $5,000 to $8,000 to produce a ton of lithium that sells for ten times that amount.  With such fat profit margins, there is no shortage of banks and investors eager to finance lithium mining and processing projects.  Such profit margins are probably not sustainable and that will likely result in more reasonable prices over time.

There is plenty of lithium in the world.  The huge demand for it is a recent phenomenon and the world is still working out how to meet that demand.

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Falling Lithium Prices Are Making Electric Cars More Affordable

Photo, posted January 9, 2023, courtesy of Phillip Pessar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Help For Kelp | Earth Wise

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The warming of the oceans has been causing the decimation of kelp forests.  The thick canopies covering coastal ocean regions have been wilting in warmer and nutrient-poor water.  Making matters much worse has been the explosion in population of sea urchins that thrive in warmer water.  The urchins gobble up the kelp, often resulting in so-called urchin barrens, largely devoid of life.

Kelp are considered a foundation species that occupy nearly half of the world’s marine ecoregions.  They thrive in cold water, where they form large underwater forests that provide essential habitat, food, and refuge for many species.  Kelp are often harvested for use in products ranging from toothpaste and shampoo to puddings and cakes.  Including the other services kelp provide, they are associated with billions of dollars in value annually.

On the North American Pacific Coast, a species of sea star consumes sea urchins.  However, these creatures are critically endangered. A marine wildlife epidemic known as sea star wasting syndrome, which began 10 years ago, has killed off more than 90% of the sunflower sea star population.   A new study by researchers at Oregon State University looked at the ability of sea stars to control sea urchin populations.

Lab experiments showed that sea stars consume urchins at a rate sufficient to maintain and possibly even restore the health of kelp forests.  The study shows that there is a clear link between the population crash of sea stars, the explosion in sea urchin populations, and the decline in kelp.

The study’s authors are calling for active management and a coordinated sea star recovery program to try to deal with the effects of a disease whose cause has not been determined.

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Sea stars able to consume kelp-eating urchins fast enough to protect kelp forests, research shows

Photo, posted December 14, 2015, courtesy of Ed Dunens via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Protecting Wetlands | Earth Wise

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Wetlands are distinct ecosystems that are flooded or saturated by water, either permanently or seasonally.  They include mangroves, marshes, swamps, forested wetlands, bogs, wet prairies, and vernal pools.   The feature that most wetlands share is soil or substrate that is at least periodically saturated with or covered by water.

Wetlands are some of the most threatened ecosystems in the world.  While wetlands can be affected by a variety of natural stressors, including erosion, droughts, and storms, human activities have been the major driver of wetland decline. 

But according to a new study by researchers from McGill University in Canada, the global loss of wetland areas since 1700 has likely been overestimated.  The research team calculated that the area of wetland ecosystems around the world has declined 21-35% since 1700 as a result of human activities – far less than the 50-87% decline estimated in other studies.  The study’s focus beyond regions with historically high wetland losses and its avoidance of possibly misleading extrapolations likely resulted in the lower estimate.      

According to the study, which was published in the journal Nature, more than 2.1 million square miles of wetlands have been lost during the past 300 years – an area roughly the size of India.  The five countries with the highest wetland losses are the United States, China, India, Russia and Indonesia. 

But discovering that fewer wetlands have been historically lost than previously thought gives researchers a second chance to protect wetlands.  The findings of the study will help researchers prioritize global conservation and restoration actions.

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A second chance to protect wetlands

Photo, posted February 2, 2005, courtesy of Jan Tik via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Solar Power At Night | Earth Wise

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The use of solar power has grown tremendously in recent years as it has declined in price and become far more competitive with other forms of electricity generation.  Its fundamental drawback, of course, is that it only works when the sun is shining.  Solar panels don’t produce any power at night.  That is, until now, apparently.

A team of engineers at Stanford University have developed a new kind of solar cell that is capable of generating at least some electricity at night.  Published in the journal Applied Physics Letters, the research describes a device that can be a continuous renewable power source for both day and nighttime.

The device incorporates a thermoelectric generator that produces electricity from the small difference in temperature between the ambient air and the solar cell itself.  The amount of power produced is far less than the solar cell generates from sunlight, but the device can provide nighttime standby lighting and power in off-grid and mini-grid applications.

Mini-grid applications are independent electricity networks that are used for small populations that may be too isolated to be connected to the main power grid.  Nearly 600 million people in Africa currently live without access to electricity, primarily in rural areas.  A standalone solar system operating independently of any power grid can meet many electricity needs such as phone charging and lighting, but such systems may not be able to handle large electrical need such as powering machinery and agricultural equipment.  Mini-grids are larger installations that can provide power to a small rural community.

With innovations like the new Stanford device, a solar mini-grid may be able to keep running at some level even at night.

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Solar panels that can generate electricity at night have been developed at Stanford

Photo, posted December 15, 2021, courtesy of Pete via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Renewables’ Growing Share | Earth Wise

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Not long ago, many states across the country were setting goals to obtain 20% of their electricity from renewable sources. For a few states, like New York and Washington, ample amounts of hydropower made 20% an easy target.  But for many others, 20% seemed like a very ambitious objective.

Things have certainly changed.  According to the latest monthly Short Term Energy Outlook, a report from the federal government, the combination of wind, solar, and other renewable sources will exceed one-quarter of the country’s generation by 2024.

Renewables are already at 24% of U.S. electricity generation and are expected to rise to 26% by next year.  Coal, which used to be the largest source of electricity, will continue to drop from its current 18% to 17% by next year.  Overall, renewables passed coal for the first full year in 2020.  Coal staged a bit of a comeback in 2021, but has once again resumed its decline.  Many coal-fired power plants continue to close, and there are not new ones being built because of diminishing economic benefits as well as concerns about emissions.

The largest source of electricity generation continues to be natural gas at 38%, but that number is also expected to slowly decrease over time. The growth in renewable energy is coming from wind and solar power.  Two-thirds of that growth is from solar and one-third is from wind. 

Together, wind and solar power will add up to 18% of the country’s electricity supply.  The government still tracks them lumped together as renewables, but both are so large and growing so quickly that the Energy Information Agency is likely to soon start tracking them as separate categories.

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Renewables Projected to Soon Be One-Fourth of US Electricity Generation. Really Soon

Photo, posted April 18, 2011, courtesy of Allan Der via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Vaccine For Bees | Earth Wise

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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

Disappearing Glaciers | Earth Wise

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Glaciers are massive bodies of slowly moving ice.  Glaciers form on land, and represent the snows of centuries compressed over time.  They move slowly downward under the influence of their own weight and gravity. 

Most of the glaciers on the planet are found in the polar regions, including Antarctica, the Canadian Arctic, and Greenland.  Glaciers can also be found closer to the equator in mountain ranges, such as the Andes Mountain range in South America.  Glaciers are always changing, accumulating snow in the winter and losing ice to melting in the summer.  But in recent times, the melting has been outpacing the accumulation.

A new international study led by researchers at Carnegie Mellon University’s College of Engineering has produced new projections of glacier loss through the century under different emissions scenarios.  According to the projections, the world could lose as much as 41% of its total glacier mass this century – or as little as 26% – depending on climate change mitigation efforts. 

In a future with continued investments in fossil fuels (sometimes referred to as the “business as usual” scenario), more than 40% of the glacial mass will be gone by 2100, and more than 80% of glaciers by number could disappear.  Even in a best case scenario where the increase in global mean temperature is limited to 1.5° degrees Celsius relative to pre-industrial levels, more than 25% of glacial mass will be gone, and nearly 50% of glaciers by number will disappear.

Glaciers take a long time to respond to changes in climate.  A complete halt to emissions today would take anywhere from 30 to 100 years to be reflected in glacier mass loss rates.

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Team projects two out of three glaciers could be lost by 2100

Ice, Snow, and Glaciers and the Water Cycle

Photo, posted August 13, 2010, courtesy of Kimberly Vardeman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tracking Global Forest Changes | Earth Wise

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India is one of the most biodiverse countries in the world.  An estimated 47,000 plant species and 89,000 animal species can be found in India, with more than 10% of each thought to be on the list of threatened species.

India is also one of the 10 most forest-rich countries in the world.  Trees cover approximately 25% of the nation.  But this is still a significant decline from years past.  In fact, between the 1890s and 1990s, a combination of rapid development and resource overexploitation caused India to lose nearly 80% of its native forest area.  Today, as India’s forests continue to disappear, researchers are trying to help preserve what forest remains. 

Using satellite-monitoring data, researchers from The Ohio State University have developed a deep learning algorithm that could provide real-time land use and land cover maps for parts of India. 

The land use monitoring system was trained using satellite data from Norway’s International Climate and Forests Initiative.  By combining this data with a global land cover map produced by Tsinghua University in China, the researcher team’s deep learning model was able to acquire a more detailed type of base map of the area.  Using their model, the researchers were able to process 10 monthly maps.  Their research was recently  presented at the annual meeting of the American Geophysical Union.   

Using these maps, the researchers were able to detect seasonal shifts across india.  These include changes to barren land, how crop land was affected by monsoons, and the distribution of forests in mountainous regions. 

Understanding the impact of these seasonal changes will help scientists better predict the effects of climate change on forests.

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Using deep learning to monitor India’s disappearing forest cover

Photo, posted January 20, 2013, courtesy of Frontier Official via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Examining The Decline Of Honey Bees | Earth Wise

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For many years, scientists have been sounding the alarm on the global struggle of pollinators.  Many of the invertebrate pollinator species, such as bees and butterflies, are facing extinction. And since 75% of the world’s food crops depend on pollination to some extent, the decline of pollinators poses a major threat to global food security.

Honey bees are among the struggling pollinators.  Over the past 14 years, bee colonies have been disappearing at an alarming rate in what is known as the “colony collapse disorder.” 

In an effort to understand why, scientists have often focused their research on environmental stressors, such as parasites, pesticides, and disease.  But according to new research by entomologists from the University of Maryland, honey bee life spans are simply 50% shorter today than they were 50 years ago.  In the study, which was recently published in the journal Scientific Reports, the researchers found that honey bees kept in a controlled, laboratory environment lived half as long as honey bees did in the 1970s.  This is the first study to show that genetics – as opposed to environmental stressors – may be influencing the broader trends seen in the beekeeping industry.

When the researchers modeled the effect of their findings on a beekeeping operation, they found that the resulting loss rates were about 33%.  This is similar to the average overwinter and annual loss rates reported by beekeepers during the past 14 years.

The next step is for researchers to compare trends in honey bee life spans across the U.S. and in other countries to see if there are differences in bee longevity. 

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Honey Bee Lifespans are 50% Shorter Today Than They Were 50 Years Ago

Helping Agriculture’s Helpful Honey Bees

Photo, posted June 23, 2007, courtesy of Susan E. Ellis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Moving Endangered Species | Earth Wise

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People have intentionally or accidentally introduced numerous invasive species to habitats around the world.  At the same time, the planet’s wildlife is in a steep decline.  A recent study estimated that the populations of over 5,000 vertebrate species have declined by an average of nearly 70% since 1970.  A United Nations report warns that human activity has threatened as many as a million species with extinction.

With all of this as a background, there is climate change that is altering the habitats of the world’s species – warming lakes and oceans, turning forests into grasslands, tundra into woodland, and melting glaciers.  In response to these changes, living things are rearranging themselves, migrating to more hospitable locations.  But many species are just not capable of finding more suitable habitats on their own.

Conservationists are now increasingly considering the use of assisted migration. In some cases, when a species’ critical habitat has been irreversibly altered or destroyed, agencies are establishing experimental populations outside of the species’ historical range.  Such actions are often deemed extreme but may be increasingly necessary.

However, clear-cut cases are relatively rare.  More likely, it is a more difficult judgement call as to whether assisted migration is a good idea or is possibly a threat to the ecosystem of the species’ new location.  The relative dearth of assisted migration experiments is less likely a result of legal barriers than it is a lack of scientific and societal consensus on the practice. Scientists are now trying to develop risk-analysis frameworks that various agencies can use in considering potential assisted migration experiments. 

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Last Resort: Moving Endangered Species in Order to Save Them

Photo, posted March 18, 2010, courtesy of Jean via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The State Of The Birds | Earth Wise

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The U.S. Committee of the North American Bird Conservation Initiative has published the State of the Birds 2022, an assessment of bird populations in North America. The news is not good.  The report identifies 70 Tipping Point species, which are those that have lost half or more of their breeding population since 1970 and are on track to lose another half or more in the next 50 years. According to research published in Science in 2019, the United States and Canada have lost 3 billion breeding birds since 1970, which is about a quarter of the total population.

More than half of the bird species in the United States are in decline. According to the Conservation Initiative, the tipping point species in particular require proactive conservation protections to avoid becoming endangered.  Species that inhabit grasslands are declining more rapidly, while waterfowl like ducks and geese are actually increasing.  That increase is most likely a result of the investments in conservation funded by the hunting industry.

Those waterfowl gains demonstrate that when there are concerted efforts to protect and promote bird populations, positve changes can happen.  Some say that protecting birds is not a high priority given all the other crises in the world, but what is good for birds is also good for people.  For example, planting trees and other vegetation to enhance bird habitat also helps to sequester carbon, protect coastlines from storm surges, increase groundwater recharge, and reduce urban heating effects.

The loss of 3 billion birds is a major biodiversity crisis and requires action.  Bird conservation benefits wildlife, people, entire ecosystems, and our planet.

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What’s Good for Birds Is Good for People and the Planet. But More Than Half of Bird Species in the U.S. Are in Decline

Photo, posted November 4, 2020, courtesy of Tom Koerner/U.S. Fish and Wildlife Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Living Planet Index | Earth Wise

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The World Wildlife Fund and the Zoological Society of London recently published the latest Living Planet Index, which is designed to measure how animal populations are changing through time.  The purpose is to provide an assessment of the health of ecosystems and the state of biodiversity.

The LPI only looks at the population of vertebrates:  birds, mammals, reptiles, amphibians, and fish.  The latest survey looked at how populations have changed between 1970 and 2018.  The results are that populations of these animal groups have declined by an average of 69% over that 48-year period.

This result highlights a very real and very severe crisis of biodiversity loss.  However, it does not mean that there are 2/3 fewer animals today than 48 years ago.  The way the index is calculated is to look at the changes in individual populations of over 5,000 different species.  Then these individual relative declines are averaged to get the result.  

There are shortcomings in the LPI.  For example, individual species that have seen massive population declines will bring the average down.  But even removing the outliers both of a negative and a positive impact does not dramatically change the result.

There is no perfect indicator for biodiversity and ecosystem health.  The Living Planet Index is nonetheless a useful metric and indicates that many species around the world are in decline.  Policymakers and environmental advocates need to make decisions about conservation and protection measures and this index is one tool they can use.

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There’s a frightening new report about wildlife declines. But many are getting the story wrong.

Photo, posted October 12, 2019, courtesy of Visit Rwanda via Flickr.

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