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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

Glacial Loss In The Swiss Alps | Earth Wise

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In 2022, glaciers in the Swiss Alps melted more than in any year on record.   This is the latest piece of bad news for the country’s glaciers, which have lost more than half of their volume of ice since the 1930s.

The melting season for Switzerland’s snow and ice typically starts in May and ends in early October.  This year’s melting season caused glaciers in the Diablerets mountain group to thin by an average of 13 feet, which is 3 times the amount of thinning observed over the past decade.   The Tsanfleuron pass between two of the glaciers is now exposed as bare rock for the first time in several thousand years. Across Switzerland, glaciers lost about 6% of their remaining volume just this year.  The previous worst year for glaciers was 2003, when losses were nearly 4%. 

There was significant melting this year in part because of the small amount of snowfall over the winter.  That snow melted quickly, being sped up by the warming effect of dust from the Sahara Desert falling on the snow.  By early summer, there was no longer a protective blanket of snow on the glaciers, exposing them to summer heat.

The loss of glaciers is far more serious than the disappearance of aesthetically pleasing landscape features.   Glaciers act as reservoirs of water that persist through the summer months.  Melt from glaciers provides water to ecosystems and creates habitats for plants and animals.  Cold runoff from glaciers affects downstream water temperatures which have a major impact on insects, fish, and other creatures.  Globally, melting glaciers contribute more than 20% of the observed ongoing sea-level rise.

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Rocky Road for Swiss Glaciers

Photo, posted June 22, 2015, courtesy of Dennis Jarvis 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

Vanishing Arctic Lakes | Earth Wise

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In recent decades, the warming in the Arctic has been much faster than in the rest of the world.  The phenomenon is known as Arctic amplification.  A study by the Finnish Meteorological Institute published in August in Communications Earth & Environment determined that during the past 43 years, the Arctic has been warming nearly four times faster than the rest of the globe.  The result of this amplified warming has been that glaciers are collapsing, wildlife is struggling, and habitats continue to disappear at a record pace.

Research published by the University of Florida has identified a new threat associated with Arctic amplification: lakes in the Arctic are drying up.

Over the past 20 years, many Arctic lakes have shrunk or dried up completely across the entire pan-Arctic region, which spans the northern parts of Canada, Russia, Greenland, Scandinavia, and Alaska.

Arctic lakes are essential elements of the Arctic ecosystem and for the indigenous communities that live in the region.  They provide a critical source of fresh water for those communities and local industries. 

The rapid decline of Arctic lakes is unexpected.  Earlier predictions were that climate change would first actually expand lakes in the region as ground ice melted.  Lakes drying out was not expected until much later in this century or even in the 22nd century.  Instead, it appears that thawing permafrost may drain lakes and overwhelm the expansion effect caused by melting ice.  The theory is that thawing permafrost decreases lake area by creating drainage channels and increasing soil erosion.

The finding suggest that permafrost thawing is occurring faster than anticipated, which presents many additional problems.

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As the climate crisis intensifies, lakes across the Arctic are vanishing

Photo, posted June 20, 2014, courtesy of Bob Wick / Bureau of Land Management via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Climate Change And Sleep | Earth Wise

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It’s no secret that our planet is heating up.  According to scientists, the warming is primarily the result of increased anthropogenic greenhouse gas emissions.  In fact, human activities are responsible for nearly all of the increase in atmospheric greenhouse gas emissions over the last 150 years. 

Climate change has already left observable effects on the planet.  For example, glaciers have shrunk, oceans have warmed, heatwaves have become more intense, and plant and animal ranges have shifted.

Most research examining the impact of climate change on human life has centered around extreme weather events and how they will affect social and economic health.  But climate change may also have a major influence on fundamental daily human activities, like sleep, that are essential to well-being.   

According to a new study recently published in the journal One Earth, scientists have found that increasing temperatures are negatively impacting human sleep around the globe.  In the study, the research team analyzed anonymized global sleep data from sleep-tracking wristbands.  The data included 7 million nightly sleep records from more than 47,000 adults across 68 countries, spanning all continents except Antarctica.     

Before the year 2100, researchers say that suboptimal temperatures may erode 50 to 58 hours of sleep per person per year.  On warm nights – where temperatures are greater than 86 degrees Fahrenheit – sleep declines an average of more than 14 minutes.  To little surprise, they found that the effect of increasing temperatures on sleep loss is substantially greater for residents in lower income countries as well as in older adults. 

Sleep is an essential restorative process integral to human health and productivity.  And it’s threatened by our changing climate. 

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Climate change likely to reduce the amount of sleep that people get per year

Photo, posted March 16, 2006, courtesy of Joe Green via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Antarctic Ice Collapse | Earth Wise

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In Antarctica, a huge chunk of the Larsen B Ice Shelf collapsed suddenly and spectacularly in January.

The Larsen Ice Shelf is located on the northeastern side of the Antarctic Peninsula on the Weddell Sea.  It was formed over the course of more than 12,000 years.  The Weddell Sea used to be a completely frozen body of water.  The famous Ernest Shackleton expedition in 1915 was trapped in its ice.  But the Antarctic Peninsula has been steadily warming in recent decades.

The Larsen A Ice shelf collapsed in 1995 and the 1,250-square-mile Larsen B Ice Shelf collapsed in 2002.  After that event, a portion of the detached ice shelf refroze in 2011 and was attached to the Scar Inlet Ice Shelf.  The refrozen ice was called the Larsen B embayment.

In January, the embayment broke apart, taking with it a portion of the Scar Inlet Ice Shelf.  It disintegrated within a matter of days.  The combined Larsen Ice Shelves – called A, B, C, and D – once extended along a 1000-mile stretch of the eastern Antarctic Peninsula.  Since 1995, it has shrunk from 33,000 square miles to 26,000 square miles.

These ice shelves float on the ocean, so their loss does not actually increase global sea levels.   However, the shelves act as dams that hold back glaciers located on the land behind them.  The loss of Antarctic ice shelves dramatically increases the rate at which glaciers flow into the sea, and that does increase global sea levels. 

Now that the sea ice from the Larsen B embayment is gone, it is likely that there will be additional inland ice losses from the newly exposed glaciers.

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Remnant of Antarctica’s Larsen B Ice Shelf Disintegrates

Photo, posted February 13, 2018, courtesy of NASA/Nathan Kurtz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Melting Himalayan Glaciers | Earth Wise

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The great mountain ranges of central Asia, including the Himalayas, contain the third-largest deposit of ice and snow in the world, trailing only Antarctica and the Arctic.  The Himalayan range contains about 15,000 glaciers, and is part of a region widely referred to as the Third Pole due to its extraordinary reserves of freshwater.

But in recent years, scientists have observed an increase in the rate of Himalayan glacier loss.  According to a new study led by researchers from the University of Leeds in the UK, the accelerating melting of the Himalayan glaciers threatens the water supply of millions of people in Asia. 

In the study, researchers reconstructed the reach of the Himalayan glaciers during the Little Ice Age, which was the last major glacier expansion 400-700 years ago. They found that these glaciers began losing ice 10 times faster during the modern era.  In fact, the glaciers have shrunk from a peak of nearly 11,000 square miles to around 7,500 square miles today.   

This exceptional acceleration of melting of the Himalayan glaciers could have significant implications.  Hundreds of millions of people rely on Asia’s major river systems for food and energy, and depend on these glaciers to feed rivers during the dry seasons.  These rivers include the Brahmaputra, Ganges, and Indus.  The changing global climate could disastrously impact water resources and livelihoods of the Greater Himalayan region.

According to the research team, people living in these regions have already seen changes that are unlike anything witnessed for centuries.  This study is the latest to confirm that these changes are accelerating and pose a significant threat to entire nations and regions. 

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Himalayan glaciers melting at ‘exceptional rate’

Photo, posted March 13, 2018, courtesy of Sarunas Burdulis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Global Flood Risk From Melting Ice | Earth Wise

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Approximately 10% of the land area on Earth is covered by ice.  This includes glaciers, ice caps, and the ice sheets of Antarctica and Greenland.  Nearly 70% of all fresh water on earth is locked away in ice.  If all this land ice were to melt, global sea levels would rise by more than 200 feet. 

According to new research led by researchers at the University of Leeds in the U.K., global warming is causing extreme ice melting events in Greenland to become more frequent and more intense over the past 40 years, leading to an increased risk of flooding worldwide.   

According to the findings, which were recently published in the journal Nature Communications, approximately 3.85 trillion tons of ice has melted from the surface of Greenland and into the ocean during the past decade alone.  That’s enough melted ice to cover all of New York City with nearly 15,000 feet of water. 

Rising sea levels threaten the lives and livelihoods of those living in coastal communities around the world.  Beyond the obvious risk of flooding in low-lying areas, rising seas also disrupt marine ecosystems that many coastal communities rely on for food and work.       

Rising sea levels can also alter patterns of ocean and atmospheric circulation, which in turn affect weather conditions around the planet.

Estimates from models suggest that melting ice from Greenland will contribute between 1 inch and 9 inches to global sea level rise by 2100. 

These findings are just another reminder of how we need to act urgently to mitigate climate change if we want to prevent the worst-case scenarios from becoming reality. 

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Increased frequency of extreme ice melting in Greenland raises global flood risk

Photo, posted April 21, 2017, courtesy of Markus Trienke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

How Quickly Can The Planet Recover? | Earth Wise

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Climate change refers to long-term shifts in temperatures and weather patterns.  Historically, these shifts were natural.  But since the Industrial Revolution, scientists have found that the main driver of climate change has been human activities, primarily by adding significant amounts of greenhouse gases into the atmosphere through the burning of fossil fuels. 

Today, climate change is destabilizing Earth’s temperature equilibrium and is having a widespread impact on humans, animals, and the environment.  Some of the consequences of anthropogenic climate change include warmer air and ocean temperatures, shrinking glaciers, increasing spread of pests and pathogens, declining biodiversity, and more intense and frequent extreme weather events. 

But how quickly can the climate recover from the warming caused by an increase in carbon dioxide in the atmosphere? 

Researchers from Johannes Gutenberg-University Mainz in Germany looked into this question by investigating the significant rise in global temperatures that took place 56 million years ago.  Likely triggered by a volcanic eruption,  the increase of between 5 and 8 degrees Celsius was the fastest natural period of global warming that has impacted the climate. 

Because higher temperatures cause rocks to weather faster, the research team decided to analyze the weathering processes that occurred during the warming event 56 million years ago.  Their findings, which were recently published in the Journal Science Advances, indicate that the climate took between 20,000 and 50,000 years to stabilize following the rise in global temperatures.

Climate change is not some distant problem.  It is happening now and it poses a serious threat to all forms of life.  We need to address the problem with more urgency. 

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How quickly does the climate recover?

Photo, posted August 27, 2017, courtesy of Lt. Zachary West (100th MPAD) / Texas Military Department via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wastewater As A Freshwater Source | Earth Wise

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Water covers three-quarters of our planet, but freshwater – the water we drink, bathe in, and irrigate crops with – comprises only 3% of the world’s water and much of that is frozen in glaciers or otherwise unavailable.  Nearly 3 billion people suffer from water scarcity for at least some of the year.

Natural freshwater sources – lakes, rivers, and groundwater – are under stress from the effects of climate change and from the increasing demands of city populations.  The wastewater treatment plants in large cities represent a significant potential water source provided that sustainable and economical technologies to produce it can be developed.

Researchers at Lehigh University in Pennsylvania have patented an innovative ion exchange desalination process that is a legitimate candidate to transform wastewater into usable water.

Existing large-scale desalination systems make use of semipermeable reverse osmosis membranes that require an energy source to run the system.  The Lehigh process, which they call HIX-Desal, harnesses the unique chemistry of carbon dioxide to take the place of the energy used in reverse osmosis systems. 

Tests of the new system show that the salinity of treated wastewater can be reduced by more than 60% by the HIX-Desal process without requiring any reverse osmosis.  At an Allentown, Pennsylvania water treatment plant where the system was tested, the researchers estimated that using the system could save about a million kWh per day in electricity usage, enough energy to power 94 homes for a year.

With this system, waste carbon dioxide from landfills or turbine exhaust can be used to desalinate municipal wastewater.  It could be the basis of a circular economy.

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Desalination tech uses CO2 to tap into municipal wastewater as alternative freshwater source

Photo, posted November 28, 2020, courtesy of Richard Ricciardi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Disappearing Mountaintop Glacier Ice | Earth Wise

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A newly released study has found that mountaintop glacier ice in the tropics of all four hemispheres has diminished dramatically over the past 50 years.  Among the findings of the study, published in the journal Global and Planetary Change, are that a glacier near Puncak Jaya, in Papua New Guinea, lost about 93% of its ice between 1980 and 2018.  Between 1986 and 2019, the area covered by glaciers on top of Mt. Kilimanjaro in Africa decreased by nearly 75%.

The study combined NASA satellite imagery with data from ice cores drilled during field expeditions on tropical glaciers around the world.  The combination of measurements demonstrated that climate change is causing these glaciers to disappear and that the ice loss has accelerated in recent years.

The study looked at glacier ice in Kilimanjaro in Tanzania, the Andes in Peru and Bolivia, the Tibetan Plateau and the Himalayas, and ice fields in Papua, New Guinea.  Collecting ice cores from these places provides information on the climate in these regions over the centuries and millennia.  As snow falls on a glacier each year, it is buried and compressed to form layers that preserve the chemistry of snow, pollutants from the atmosphere, and biological material such as plants and pollen.

Glaciers in the tropics respond more quickly to climate change because they exist in the warmest areas of the world and survive only at very high altitudes. For many of these tropical glaciers, it is too late to prevent their demise.  It is not too late to attempt the slow down the buildup of greenhouse gases in the atmosphere that is causing the planet to warm, but we don’t have unlimited time to act.

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Mountaintop glacier ice disappearing in tropics around the world

Photo, posted February 12, 2009, courtesy of Christoph Strassler via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Coastlines and Climate Change | Earth Wise

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Climate change poses a fundamental threat to life on earth and has already left observable effects on the planet.  For example, glaciers have shrunk, oceans have warmed, heatwaves have become more intense, and plant and animal ranges have shifted. 

As a result of the changing climate, coastal communities around the world are confronting the increasing threats posed by a combination of extreme storms and the predicted acceleration of sea level rise. 

Scientists from the University of Plymouth in England have developed a simple algorithm-based model to predict how coastlines could be affected by climate change.  This model allows coastal communities to identify the actions they need to take in order to adapt to their changing environment.

The Forecasting Coastal Evolution (or ForCE)  model has the potential to be a game-changer because it allows adaptations in the shoreline to be predicted over timescales of anything from days to decades. As a result, the model is capable of predicting both the short-term impact of extreme storms as well as predicting the longer-term impact of rising seas.   

The ForCE model relies on past and present beach measurements and data showing the physical properties of the coast.  It also considers other key factors like tidal, surge, and global sea-level rise data to assess how beaches might be impacted by climate change.  Beach sediments form the frontline defense against coastal erosion and flooding, and are key in preventing damage to valuable coastal infrastructure.

According to the study, which was recently published in the journal Coastal Evolution, the ForCE model predictions have shown to be more than 80% accurate in current tests in South West England.

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New model accurately predicts how coasts will be impacted by storms and sea-level rise

Photo, posted April 17, 2016, courtesy of Nicolas Henderson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rising Seas And Wastewater Leakage | Earth Wise

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Global mean sea level has risen nearly 9 inches since 1880, with over two inches of that over just the last 25 years.  The rising water level is primarily due to two factors:  additional water in the oceans coming from melting glaciers and ice sheets; and the thermal expansion of seawater as it warms.  Climate models estimate that over the course of the century, global sea levels will rise at least a foot even if efforts to reduce greenhouse gas emissions are quite successful and, in the worst case, levels could rise as much as 8 feet.

Faced with this situation, the greatest concerns are, initially, increasing amounts of coastal flooding and erosion and, as things get worse, inundation of coastal regions making many places uninhabitable and creating millions of climate refugees.

Recently, computer modeling studies have focused on an additional imminent problem:  the flooding of coastal wastewater infrastructure, which includes sewer lines and cesspools.

A new study by the University of Hawaii at Manoa is the first to provide direct evidence that tidally driven groundwater inundation of wastewater infrastructure is already occurring in urban Honolulu.  The study shows that higher ocean water levels are leading to wastewater entering storm drains and the coastal ocean.  The result is degradation of coastal water quality and ecological health.

The researchers used chemical tracers to detect groundwater discharge and wastewater present at multiple low-lying areas during spring tides.  During high tides, storm drains become channels for untreated wastewater to flood streets and sidewalks. 

People tend to think of sea-level rise as a future problem, but there are already serious effects going on today that are only going to get worse.

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Sea-level rise drives wastewater leakage to coastal waters

Photo, posted August 23, 2011, courtesy of Eric Tessmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Caspian Sea And Climate Change | Earth Wise

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According to the National Oceanic and Atmospheric Administration, global sea levels have been rising over the past century, and the rate has increased in recent decades.  Sea levels are currently rising about one-eighth of an inch every year.

Sea level rise is caused primarily by two factors related to climate change:  the added water from melting glaciers and ice sheets, and the expansion of seawater as it warms.  While climate change is causing global sea levels to rise, higher temperatures in other regions are having exactly the opposite effect.  The water levels are falling.

According to researchers from the University of Bremen in Germany, the Caspian Sea is a perfect example of how a body of water will change.  While it is named a sea due to its size and high salinity, the Caspian Sea is actually a lake.  In fact, it’s the largest lake in the world.  Its largest inflow is the Volga River and it has no natural connection to the ocean.  Its water level is determined by the proportional influences of inflow, precipitation, and evaporation.  Climate change is causing increased evaporation, which leads to a declining water level. 

According to the research team, the water level of the Caspian Sea could fall by 29 to 59 feet during this century.

The Caspian Sea is surrounded by Kazakhstan, Turkmenistan, Iran, Azerbaijan and Russia.  It’s an important regional water reservoir, and a biological and commercial center. 

The researchers hope the Caspian Sea will be used as an example in scientific research to assess the vulnerability of other regions to falling water levels.

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Climate crisis is causing lakes to shrink

Photo, posted October 31, 2016, courtesy of Amanderson2 via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Dust And Himalayan Glaciers | Earth Wise

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Glaciers in the Himalayas have been melting and retreating, as have glaciers around the world.  As is the case elsewhere, human-driven climate change is a major factor.  But at the lofty heights of the Himalayas, warming temperatures are not the biggest culprit.  Black carbon – released into the air by burning fossil fuels or biomass such as plants, trees, and shrubs – darkens the snow and causes it to absorb more of the sun’s heat.  A recent study by an international team of scientist has identified another important factor:  dust.

An estimated 5 billion tons of desert dust enters the Earth’s atmosphere every year.  Dust from places like Saudi Arabia gets picked up by spring winds and gets deposited on the western sides of mountains, where it can make the air 10 times more polluted than most European cities.  Dust blows across industrial and desert areas in the Indian subcontinent and the Middle East and lands in the Himalayas.  According to the new study, this dust is often the dominant cause of snow melt in those areas.

Desert dust causes snow melt in the same way that black carbon does.   Dirty snow absorbs sunlight more easily than clean snow.

Desert dust is a natural part of Earth’s systems, but the amount of it in the atmosphere has steadily increased since the Industrial Revolution, when humans greatly expanded into desert areas and broke through surface crust that held large amounts of dust in place.

There is not much we can do about desert dust, short of eliminating deserts.  But the disappearance of the Himalayan ice pack – which sustains over a billion people – can be mitigated by reducing greenhouse gas emissions to address climate change .

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Himalayan glaciers melting because of high-altitude dust

Photo, posted March 13, 2018, courtesy of Sarunas Burdulis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Danger For North American Biomes | Earth Wise

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Biomes are large, naturally occurring communities of flora and fauna that occupy a major habitat.  Examples include several different kinds of forests, grasslands, deserts, and tundra.  According to a new study published in the journal Global Change Biology, the resilience of North America’s plant biomes is declining, which means that they are in danger of succumbing to a major extinction event.

The research analyzed over 14,000 fossil pollen samples from 358 sites across North America for the purpose of reconstructing their “landscape resilience”, meaning the ability of the habitats to persist or quickly rebound in response to disturbances.

Some 13,000 years ago, North American ecosystems were destabilized by the one-two punch of the retreat of glaciers at the end of the last ice age along with the arrival of humans.  That combination resulted in the extinction of large terrestrial mammals on the continent. 

Today, there is a comparable one-two punch created by the rapidly changing climate combined with the dramatic expansion of the footprint of human civilization.   The result could again be the demise of some of North America’s biomes.  In past eras, forests persisted longer than grasslands, but also took longer to reestablish after disruptions.  Overall, only 64% of historic biomes regained their original ecosystem type.

The scientists said that strategic conservation effects could help counteract or slow down the impacts of climate change in the coming decades.  In particular, efforts focusing on improving landscape and ecosystem resilience by increasing local connectivity and concentrating on regions with high richness and diversity could have the greatest positive effect.

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North American Biomes Are Losing Their Resilience, With Risks for Mass Extinctions

Photo, posted January 9, 2020, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Greenland Glaciers Past The Point Of No Return | Earth Wise

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Forty years of satellite data from Greenland shows that the glaciers on the island have shrunk so much that even if global warming came to an abrupt halt, the Greenland ice sheet would continue to shrink.

This conclusion was published in the journal Communications Earth and Environment by researchers at Ohio State University.  According to their study, Greenland’s glaciers have passed a tipping point where the snowfall that replenishes the ice sheet each year can no longer keep up with the ice that is flowing into the ocean from the glaciers.

The study analyzed monthly satellite data from more than 200 large glaciers that drain into the ocean around Greenland.  It looked at how much ice breaks off into icebergs or melts from the glaciers into the ocean as well as the amount of snowfall each year that replenishes the glaciers.

Throughout the 1980s and 90s, these two processes were mostly in balance, keeping the ice sheet intact.  But the amount of ice being lost each year started to increase steadily around the year 2000 while there was no increase in snowfall.   Both processes fluctuate from year to year, but the baseline for ice loss has steadily risen.  Before 2000, the Greenland ice sheet had about the same chance of gaining or losing mass each year.  At this point, the ice sheet is likely to gain mass in only one out of every 100 years.

Large glaciers in Greenland have retreated about 2 miles since 1985, so that many of them are sitting in deeper water with more ice in contact with warmer water making it harder for glaciers to grow back.  At this point, even if the climate reverses its trend, the ice sheet will continue to lose mass.

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Warming Greenland ice sheet passes point of no return

Photo, posted August 27, 2015, courtesy of Joxean Koret via 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.

Boutique Hotels For Birds | Earth Wise

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The changing Arctic climate has had a drastic effect on its seabirds.  In fact, seabirds worldwide are in crisis, with global populations plummeting nearly 70% over the past 70 years as a result of climate change, over-fishing, habitat loss, and other human impacts on their environment.

Above the Arctic circle in Norway, seabird behavior has changed dramatically.  Black-legged kittiwakes – which are the most seafaring member of the gull family – used to nest in cliffs over the ocean and seldom ventured inland.  But in recent years, that has changed.  Because of a warming ocean, increased storminess and other changes that are decimating chick populations in their normal habitat, the birds have been setting up housekeeping in places like shopping centers and office buildings in Tromsø and other towns along Norway’s north coast.

Tromsø, Hammerfest and other towns at the very north end of Norway have become very popular with tourists seeking the Northern Lights and wanting to see glaciers before they disappear.  The booming tourism has been put on hold for the moment as it has elsewhere, but when it returns, the regions growing hotels and shopping areas are facing a problem.

The birds taking up residence on these buildings are unpleasant neighbors.  They are especially noisy during the breeding season and people are having to put up nets or spikes on buildings to discourage the kittiwakes from settling there.

Local ecologists are now building boutique hotels just for kittiwakes. Using abandoned buildings on piers, they are adding ledges for nesting, materials for nest-building, and electronic speakers that croon kittiwake songs.  The hope is that the birds will stay in their own hotels and leave the other ones for the human tourists.

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Norwegians are building boutique hotels for threatened Arctic birds

Photo, posted April 14, 2018, courtesy of Charlie Jackson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Record Antarctic Temperature | Earth Wise

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It is still early in the year, but extreme weather events are already piling up.  January was the warmest month on record globally and there have been many records shattered in Europe and Asia.  A number of places in Eastern Europe, including parts of Russia, have seen temperatures 12 to 13 degrees above average.

While the warming of the Arctic has been in the news with increasing frequency, the Antarctic is also seeing rising temperatures and is one of the fastest-warming regions in the world. 

On February 6th, Esperanza Base along Antarctica’s Trinity Peninsula measured a temperature of 65 degrees Fahrenheit, which is the highest temperature ever recorded on that continent.   This rather balmy temperature narrowly beat out the previous record of 63.5 degrees, which occurred in March of 2015.

This one-time reading is certainly anomalous, and scientists say it is associated with a ridge of high pressure that was lingering over the region for several days.  Local wind conditions led to additional warming.

However, the conditions leading to record-breaking high temperatures are not one-time anomalous events. Over the past 50 years, temperatures in the Antarctic have surged by an extraordinary 5 degrees in response to the Earth’s rapidly warming climate.  A rise of five degrees in day-to-day weather is no big deal. A five-degree rise in a region’s average temperature is enormous.

About 87% of the glaciers along the west coast of Antarctica’s Trinity Peninsula have retreated over that 50-year period, most of which doing so during just the past 12 years.

Some researchers claim that the new temperature record is an extreme event that doesn’t tell us anything about the changing climate.  Many others are convinced that there will be many more high temperature records to follow.

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Antarctica just hit 65 degrees, its warmest temperature ever recorded

Photo, posted February 24, 2019, courtesy of Mike via 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...)