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Melting in Svalbard

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Svalbard is a Norwegian archipelago north of the mainland.  It is known for its glaciers, tundra, and wildlife – especially polar bears, Arctic foxes, and reindeer.  It is home to the Svalbard Global Seed Vault, a place to safeguard critical seeds for the world’s food supply.  The location was chosen for its remoteness and perpetual deep freeze.

A recent study investigated the record glacial ice melt on the Svalbard islands in the summer of 2024, considering it to be a cautionary tale about the future of other Arctic ice masses.

The amount of ice that melted on Svalbard made it one of the most significant contributors to global sea level rise last year.  An extreme and long Arctic heat wave, intensified by changing weather patterns, led to unprecedented melting.  But what seemed like a once-in-1000-year event may well become normal in the future.

Most of the 2024 glacial melt occurred during six weeks of record-high temperatures.  The influx of fresh water from the islands most likely had an impact on marine ecosystems in the surrounding sea, beginning at the bottom of the food chain with plankton, which are very sensitive to water temperature and salinity. 

Research has linked surges of fresh water into the North Atlantic with extreme weather in Europe and possibly even North America.  Of great concern is that cold fresh water flowing out of the Arctic may be contributing to the weakening of the Atlantic Meridional Overturning Circulation, which is a key ocean current that carries warm water towards northwestern Europe and greatly impacts the climate in Europe.

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Melting on the Arctic’s Svalbard Islands Shows the Climate Future Is Now

Photo, posted September 21, 2016, courtesy of Christopher Michel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

An ice-free Arctic

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According to a new study by Colorado University, Boulder, the Arctic could see summer days with practically no sea ice as soon as sometime in the next few years.  Earlier predictions for when the first ice-free day in the Arctic could occur were sometime well into the 2030s.

By mid-century, the Arctic is likely to see an entire month without floating sea ice.  This would likely be in September, when ice coverage is at its minimum.  By the end of the century, the ice-free season could last for many months during the year.

Technically, an ice-free Arctic does not mean zero ice in the water.  The working definition is less than 386,000 square miles of ice, which represents less than 20% of what the minimum ice coverage was in the 1980s. In recent years, the coverage has been about 1.25 million square miles.

Sea ice coverage is a big deal because many Arctic animals rely on sea ice for survival, including seals and polar bears.  With warmer ocean water, invasive fish species could move into the Arctic Ocean, upsetting local ecosystems.  Sea ice loss also is a risk for coastal communities because the ice buffers the impact of ocean waves on the coastal land.  As the ice retreats, ocean waves would get bigger, eroding the coasts.

At this point, an ice-free Arctic is basically inevitable, but its annual duration will depend on society’s efforts to reduce carbon emissions.  Lengthy periods of minimal sea ice would transform the Arctic into a completely different environment with global effects that are mostly highly undesirable.  However, Arctic sea ice is resilient and could return fairly quickly if the atmosphere cools down.

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The Arctic could become ‘ice-free’ within a decade

Photo, posted July 9, 2022, courtesy of Reiner Ehlers via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Polar bears and the changing climate

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The changing climate poses a major threat to polar bear survival.  Polar bears, whose native range lies largely within the Arctic Circle, depend on sea ice for nearly all of their lifecycle functions.  Rising global temperatures are causing this sea ice to disappear.

With less sea ice, polar bears are forced to stay longer on land.  However, according to a new study led by researchers from Washington State University, more time stranded on land leads to a greater risk of polar bear starvation. 

During three summer weeks in Manitoba, Canada, 20 polar bears observed by researchers tried different strategies to maintain energy reserves.  But the research team found that nearly all of them lost weight – losing about 2.2 pounds per day on average.     

Some scientists have speculated that polar bears might be able to adapt to the changing climate by acting more like grizzly bears by either resting or eating terrestrial food.  But the polar bears tried versions of both strategies – with little success.

Polar bears can weigh nearly twice as much as grizzly bears.  To maintain this size, polar bears rely on the energy-rich fat of seals, which they best catch on ice.

In the study, which was recently published in Nature Communications, the researchers found that some polar bears laid down to conserve energy, while others searched on land for food.  But neither the activity nor the lack thereof paid off.  In fact, only one bear out of the 20 gained weight after stumbling across a dead marine mammal on land.

Polar bears across the Arctic are at risk of starvation as the ice-free period continues to grow.

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Polar bears unlikely to adapt to longer summers

Photo, posted November 16, 2015, courtesy of Anita Ritenour via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Arctic Warming And Weather At Mid-Latitudes | Earth Wise

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Some of the most striking images of climate change are those of melting glaciers in the Arctic and polar bears stranded on shrinking sea ice. The Arctic has been warming at a rate twice as fast as the global average.  In recent years, there has been growing recognition of the Arctic’s role in driving extreme weather events in other parts of the world.

Winters in the midlatitude regions have seen more extreme weather events.  The past winter saw record-breaking cold temperatures and snowfall in Japan, China, and Korea.   Many parts of Eurasia and North America experienced severe cold snaps, with heavy snowfall and prolonged periods of subzero temperature.  On the other hand, Europe saw its second warmest winter on record with record high temperatures in many places, much drier than normal conditions, and the closure of many ski resorts.

A study published in the journal Climate and Atmospheric Science by scientists from South Korea and the U.S. looked at various climate projection models as well as historic climate data to assess what is likely to happen to weather in the mid-latitudes as the Arctic continues to warm.  Warmer Arctic Sea temperatures usually result in lower winter temperatures in East Asia and North America as ocean currents and the jet streams are altered.

The study shows that Arctic warming-triggered cold waves in the mid-latitudes are likely to persist in a warmer future, but that such events will become more difficult to predict.  The study highlights the importance of continued efforts to better understand the interactions between Arctic warming and the climate of the midlatitudes.   There need to be better ways to predict the extreme weather events that are likely to come.

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Gwangju Institute of Science and Technology Researchers Correlate Arctic Warming to Extreme Winter Weather in Midlatitude and Its Future

Photo, posted August 31, 2006, courtesy of Hillebrand / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Polar Bears and Tires | Earth Wise

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There is lots of interest in traction.  People want to find better ways to move across wet and frozen surfaces safely.   This applies to both the shoes on our feet and the tires on our cars. 

Researchers at the University of Akron along with colleagues at Syracuse University and at Bridgestone, the tire company, have been studying how many arctic animals can walk and run across the ice without slipping and falling.  Their research focused on the paws of polar bears.

Previous studies discovered that polar bears have papillae – little bumps on the pads of their feet – that provide improved traction on snow.  The new research also looked at the paws of other species of bear – brown bears and black bears – and found that these others also have papillae on their paw pads, but that those of polar bears are as much as 50% taller.  These taller bumps give the pads a 30-50% increase in frictional shear stress.

The research may lead to various applications. For example, snow tires typically have deeper treads, but the polar bear study may lead to some new designs that would improve traction.  People who do high-altitude climbing are interested in the research as are companies that deliver goods in bad weather.  Anyone who has to be out and about in bad weather would like to get a better grip.

There are various other animals with traction-improving adaptations that are probably worth studying.  These include dogs, wolves, foxes, and mountain goats.  The same researchers at Akron have also studied other animals with unique abilities to deal with challenging surfaces including geckos, spiders, and mussels.  The natural world is filled with examples of creatures who can easily function in environments that we humans find very challenging.

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UA researchers’ focus on tire traction leads to investigation of polar bear paws

Photo, posted March 2, 2008, courtesy of Sam Weng via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Polar Bears And Melting Sea Ice | Earth Wise

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Climate change poses a major threat to polar bear survival.  The polar bear, whose native range lies largely within the Arctic Circle, depends on sea ice for nearly all of its lifecycle functions.  And rising temperatures are causing this sea ice to disappear.

Climate change-driven sea ice loss is the primary threat to the future of this iconic species.  In fact, polar bears were the first animal listed as endangered because of the forecasted impacts of climate change.   

Melting sea ice as a result of climate change continues to plague polar bear survival.  According to a new study by researchers from Washington State University, polar bears in the Beaufort Sea have had to travel far outside their traditional arctic hunting grounds in recent years for food.  This has contributed to an almost 30% decrease in their population. 

Researchers used satellite tracking data to analyze the movement patterns of female polar bears from 1986-2016 in the Beaufort Sea area north of Alaska.  Over the last two decades, they found that polar bears are having to travel farther north of their traditional hunting grounds on the continental shelf to remain on their receding sea ice habitat.

The research team also found that around 20% of the polar bear population in the Beaufort Sea is foregoing its traditional sea ice hunting grounds altogether in the summer and fall.  Instead, these bears are moving inland in search of food.  

Scientists estimate that 800 or so polar bears remain in the southern Beaufort Sea.  Curbing global greenhouse gas emissions in order to protect polar bear habitat may be the only way to help these animals survive. 

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Melting sea ice forces polar bears to travel farther for food

Photo, posted September 27, 2015, courtesy of Anita Ritenour via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Drilling Rights In The Arctic National Wildlife Refuge | Earth Wise

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The battle to prevent oil and gas drilling rights from being sold in the Arctic National Wildlife Refuge in Alaska has been going on for 40 years.  The Trump administration spent nearly four years pushing to auction off those drilling rights and finally accomplished it in early January.

The ANWR was created in 1960 and is the largest intact wilderness in the U.S., covering nearly 30,000 square miles in Alaska.  It is an important breeding habitat for polar bears as well as the home of more than 200 other species including caribou, arctic foxes, golden eagles, and snowy owls.  Parts of it are also sacred ground for the indigenous Gwich’in people.

The auction carved out a 5% slice of the refuge for leases and proponents anticipated it would generate billions of dollars in revenues that would offset tax cuts in Alaska.

Of the 22 parcels of land offered, totaling 1.1 million acres, only 12 were bid on at all and the state of Alaska was the sole bidder on 9 of those.  In total, the auction raised a paltry $14 million. 

Whether the remarkable absence of interest was due to a lack of infrastructure or roads around the region, the decline of fossil fuel investments and use during the pandemic, or the anticipation that any leases would be the subject of endless legal battles by indigenous tribes and environmental activists, the net result was that the auction was basically a flop.

President Biden has stated that he is entirely against Arctic drilling, so the new administration is likely to try to repeal or interfere with any drilling leases or other industrial activity in the ANWR. 

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Arctic Oil Drilling Plans Suffer ‘Stunning Setback’ as Almost ‘No One Shows Up’ For the Sale

Photo, posted July 3, 2019, courtesy of Alaska Region U.S. Fish and Wildlife Service via Flickr. Photo Credit: Danielle Brigida/ USFWS

Earth Wise is a production of WAMC Northeast Public Radio.

An Ecological Trap For Polar Bears | Earth Wise

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Climate change has been shrinking Arctic sea ice and this is causing changes in the behavior of polar bears.   The Southern Beaufort Sea, located where the northern edges of Alaska and Canada meet, is home to one of the 19 population groups of polar bears.  Historically, the polar bears in this region remained on sea ice year-round.  But in recent decades, about a quarter of them have chosen to come on land instead of staying on the shrinking summer ice platform.

A recent study by San Diego Zoo Global, the U.S. Geological Survey, and Polar Bears International looked at the energetic consequences of the bears’ behavior.  The decision of each individual bear to stay on the ice or move to land appears to be linked to the energetic cost or benefit of the choice.

Bears who moved to land expended more energy during the summer than bears that remained on the sea ice.  In late summer, as the ice became even more restricted, a greater amount of energy was expended by bears swimming to land.  So, the immediate energy cost of moving to land is much greater than remaining on the receding pack ice.

On the other hand, bears on land in this region have access to whale carcasses in the summer while bears on the sea ice appear to be fasting.  As a result, it may be the case that the declining population of bears in this region is in part caused by the ecological trap of bears staying on the ice to avoid expending all the energy needed to move to land.  The shrinking polar ice is a real problem for polar bears.

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Energetics Study Indicates that Shrinking Sea Ice Is Creating an Ecological Trap for Polar Bears

Photo, posted October 30, 2011, courtesy of Martin Lopatka via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Polar Bear Attacks

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The increasing reduction of sea ice in the Arctic is changing the behavior of polar bears.  Because they are spending more time on land, they are interacting with people much more frequently, occasionally with deadly results.

A study, published in 2017, looked at 144 years’ worth of polar bear attacks on humans in the Arctic.  Between 1960 and 2009, there were a reported 47 attacks by polar bears on people – between 7 and 12 per decade.  Between 2010 and 2014, as sea ice reached record lows, there were 15 attacks, a record for a four-year period.  Since 2000, 88% of attacks have occurred between July and December, when sea ice is at its lowest level of the year.

Last July, a young male polar bear attacked and killed a man who was berry picking with his children.  A month later, a mother polar bear attacked and killed an Inuit hunter and injured two others.  This was the first known fatal attack by a mother polar bear.

As a result, Inuit communities in the Nunavut region are asking for higher legal polar bear harvest quotas, arguing that bear populations have increased to a dangerous level.

These recent human fatalities have also provided an impetus for developing new non-lethal conflict-resolution tools than can be used in northern communities before more people as well as bears are killed.

There are now polar bear patrol teams tasked with driving bears away from settlements.  There is a bear hotline and electric fencing around sled dog compounds.

The changing face of the Arctic is creating growing stress on the polar bear population and on the people who make their home in that region.

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As Polar Bear Attacks Increase in Warming Arctic, a Search for Solutions

Photo, posted September 28, 2015, courtesy of Anita Ritenour via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Polar Bears Are Struggling To Find Food

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Climate change continues to pose a major threat to polar bear survival.  Polar bears, whose native range largely lies within the Arctic Circle, depend on sea ice for nearly all of their life cycle functions.  And rising global temperatures are causing that sea ice to disappear. 

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