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Fire And Ice | Earth Wise

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In recent years, there have been countless stories about the effects of the changing climate.  Many of those stories have been about the dwindling sea ice in the Arctic and many others have been about the worsening wildfires in the western United States.   According to a recent study published by the Pacific Northwest National Laboratory, those two things are very much related.

As sea ice in the Arctic melts from July to October, sunlight warms the surrounding land and sea surfaces.  The resulting differences in air pressure create and strengthens a vortex in the atmosphere above the heated area which spins counterclockwise like a cyclone.

The powerful vortex pushes the polar jet stream out of its typical pattern and diverts moist air away from the western United States.  With the jet stream moved off its usual course, a second vortex, this time spinning clockwise, forms under the ridge of the polar jet stream above the Western U.S.  This second vortex brings with it clear skies and dry conditions:  fire-favorable weather.

Arctic sea ice has continually declined at least since the late 1970s.  It is predicted that there will be periods of entirely iceless Arctic waters before the 2050s.  In turn, conditions in the already fire-ravaged West are likely to be further exacerbated.  More than three million acres have burned across California alone during the 2021 wildfire season.

Climate conditions in one part of the world can, over time, influence climate outcomes thousands of miles away.  The research at Pacific Northwest Laboratory reveals how regional land and sea surface warming caused by Arctic ice melting can trigger hotter and drier conditions in the West later in the year.

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Fire and Ice: The Puzzling Link Between Western Wildfires and Arctic Sea Ice

Photo, posted July 28, 2018, courtesy of Bob Dass 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.

July Was A Scorcher | Earth Wise

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July 2021 has the unfortunate distinction as being the world’s hottest month ever recorded according to global data from the National Oceanic and Atmospheric Administration.   July is typically the warmest month of the year, but this July was the warmest month of any year on record.

The combined global land and ocean surface temperature was 62.07 degrees Fahrenheit, which is 1.67 degrees above the 20th century average.  This was the highest monthly average since records began 142 years ago.  It broke the previous record set in July 2016 and tied in 2019 and 2020.

The Northern Hemisphere was 2.77 degrees above average.  Asia had its hottest July on record.  Europe had its second hottest July on record.  Places like Africa, Australia, and New Zealand all had top-ten warmest Julys.

Other aspects of the changing climate included the observation that Arctic sea ice coverage for July was the fourth-smallest in the 43-year record.  Interestingly, Antarctic sea ice extent was actually above average in July.  Global tropic cyclone activity this year so far is above normal for the number of named storms.  In the Atlantic basin, the formation of the storm Elsa on July 1 was the earliest date for a 5th named storm.

It remains very likely that 2021 will rank among the 10 hottest years on record.  Extreme heat is a reflection on the long-term climate changes that were outlined recently in a major report released by the Intergovernmental Panel on Climate Change.  These latest global observations add to the disturbing and disruptive path that the changing climate has set for the world.

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It’s official: July was Earth’s hottest month on record

Photo, posted July 15, 2021, courtesy of Lori Iverson/National Interagency Fire Center via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Heat In The Arctic | Earth Wise

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By mid-November, the Arctic stays dark around the clock and twilight does not return until the end of January.  But even as winter darkness descended upon the Arctic this year, record-breaking high temperatures in the region continued.  In late November, temperatures across the entire Arctic basin were 12 degrees Fahrenheit above normal and some locations saw temperatures as high as 30 degrees above normal.

The entire summer and fall in the Arctic were characterized by exceptionally warm temperatures.  In June, the Siberian town of Verkhoyansk – located north of the Arctic Circle – registered a high temperature of 100.4 degrees.  The refreezing of the Arctic Ocean was greatly delayed this year.  The Northeast Passage along the Siberian Coast remained navigable for a record 112 days before freezing in November, breaking the previous record by more than a month.  The extent of sea ice covering the Arctic Ocean in October was the lowest ever recorded for that month.

The strongest warming occurring in the Arctic is during the fall.  That is because rapidly disappearing sea ice is enabling the dark waters of the Arctic Ocean to absorb heat in the summer and then radiate it back into the atmosphere until late in the fall.  The Arctic region is heating up three times faster than the rest of the planet, which has led to the volume of sea ice decreasing by 2/3 in the past 40 years.

According to researchers, the extreme heat in Siberia this year would have been virtually impossible without human-caused climate change and became 600 times more likely because of human emissions of greenhouse gases.

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Record-shattering Warmth Pushes Arctic Temperatures to 12 Degrees F Above Normal

Photo, posted September 1, 2009, courtesy of the U.S. Geological Survey via Flickr. Photo Credit: Patrick Kelley, U.S. Coast Guard.

Earth Wise is a production of WAMC Northeast Public Radio.

The Hot Year Continues | Earth Wise

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The National Oceanic and Atmospheric Administration’s monthly global climate report for October reports yet another month of high temperatures.  October 2020 was the fourth-hottest October on record, continuing the pace for the year to be the second hottest on record.

The 10 warmest Octobers have occurred since 2005 and the seven warmest have all occurred in the last seven years.  Europe had its warmest October ever, surpassing the previous record set in 2001.

For the year to date, the global temperature was a full degree Celsius (or 1.8 degrees Fahrenheit) above the 20th century average.  This was just 0.03 Celsius degrees lower than the record set in 2016.   Europe and Asia have had their warmest year-to-date period on record.

Other notable observations in the report included that Arctic sea ice coverage was almost 37% below the 1981-2010 average and was the smallest October coverage on record.  The previous record was set last year.

Heat records were set around the world including parts of the northern and western Pacific Ocean, southern North America, South America, eastern Europe, the northern Middle East, the eastern Mediterranean Sea, southern Asia, and in small areas across the Indian and Atlantic Oceans.

Despite the record global temperatures, the Northern Hemisphere’s snow coverage in October was the 10th largest over the past 53 years.  The snow coverage in North America was the largest on record for October.

Adding in the extremely active hurricane season, with 12 hurricanes and 29 tropical depressions, weather around the world continues to be anything but typical.

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Remarkably warm October fuels march toward 2nd-hottest year

Photo, posted February 8, 2016, courtesy of Jasmin Toubi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Arctic Methane Starting To Release | Earth Wise

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An international team of researchers has found evidence that frozen methane deposits in the Arctic Ocean have started to be released over a large area of the continental slope off the East Siberian coast.  High levels of methane have been detected down to a depth of 1,100 feet in the Laptev Sea near Russia.

The slope sediments in the Arctic contain huge quantities of methane and other gases, known as hydrates.  Methane has a warming effect 80 times stronger than carbon dioxide over a 20-year period.  The US Geological Survey has identified Arctic hydrate destabilization as one of the four most serious scenarios for abrupt climate change.

The research team aboard a Russian ship said that most of the bubbles they observed coming up from the sea bottom were dissolving in the water, but that methane levels at the surface were four to eight times what would normally be expected.

Frozen methane deposits have been called the “sleeping giants of the carbon cycle.”  If these deposit releases were to reach a high enough level, it would be a tipping point that could greatly increase the speed of global warming.  With Arctic temperatures now rising more than twice as fast as the global average, the likelihood of a significant release of the frozen methane grows greater all the time.

Temperatures in Siberia were 9 degrees Fahrenheit higher than average from January to June this year.  Last winter’s sea ice melted unusually early.  This winter’s freeze has yet to begin, which is already a later start than any time on record.

These new discharges of methane are larger than anything found before and are a very worrisome occurrence.

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Arctic methane deposits ‘starting to release’, scientists say

Photo, posted September 26, 2014, courtesy of the Office of Naval Research via Flickr. Photo credit: U.S. Navy photo by John F. Williams/Released.

Earth Wise is a production of WAMC Northeast Public Radio.

The Arctic Northeast Passage May Open | Earth Wise

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The Northwest Passage is the sea route between the Atlantic and Pacific oceans through the Arctic Ocean.  It goes along the northern coast of North America, traveling though the Canadian Arctic Archipelago.  In the past, it was the domain of intrepid explorers like Roald Amundsen.  Because of the receding ice in the Arctic, in recent years it has become possible to travel the Northwest Passage by cruise ship.

The Northeast Passage connects the same two oceans along the Arctic coasts of Norway and Siberia.  The sustained loss of sea ice is now leading to accessibility of Arctic sea passages through this route.

Compared with the customary route through the Strait of Malacca in Malaysia and the Suez Canal, using the Northeast Passage could reduce the travel distance between Europe and northwest Asia by one-third.  This would reduce the expense of transportation and lower environmental pollution.  Many Asian countries have a strong strategic and economic interest in Arctic shipping.  Russia would gain strong competitive advantages for its liquified natural gas industry.

According to a recent study at the Northwest Institute of Eco-Environment and Resources of the Chinese Academy of Sciences, the continuing warming of the Arctic seas is likely to result in the Northeast Passage being navigable for open water ships by next year and will continue to be increasingly hospitable to marine traffic.

The economic and strategic benefits to the opening of the Northeast Passage are quite clear.  What is also clear is that the underlying cause of the opening of the passage – the dramatic loss of Arctic sea ice – is not beneficial to the world at all and is a harbinger of troubling things in our future.

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Arctic Northeast Passage may be Navigable in Near Future

Photo, posted September 24, 2005, courtesy of Paul Downey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Hottest September | Earth Wise

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Here’s a news item that is like many other recent news items:  September 2020 was the hottest September since 1880, according to the National Oceanic and Atmospheric Administration.   The warm September is a part of a year that so far is poised to be at least the second hottest year in the 141-year climate record.

The ten warmest Septembers on record have all occurred since 2005, and the seven warmest Septembers have occurred in the past seven years.

So far, the year-to-date average global temperature has been the second warmest on record, being just 0.07 degrees Fahrenheit lower than the record year-to-date temperature set in 2016.  Expectations are that 2020 will end up somewhere among the three warmest years on record for the globe.

September was warm in many places around the world.  California and Oregon had their warmest September ever.  Europe had its warmest September on record, Asia had its second warmest September on record as did Australia and South America. 

So far, it has been the hottest year-to-date on record in Europe, Asia, and the Gulf of Mexico.  No land or ocean areas anywhere had record-cold year-to-date temperatures. 

Global temperatures represent an average over the entire surface of the planet.  The fact that the global temperature is now nearly one Celsius degree above the 20th century average means that a vast amount of heat has been added in order to warm all the oceans, atmosphere, and land by that much.  So, every uptick in global temperature is a big deal.

Meanwhile, the average Arctic sea ice coverage for September was the second smallest on record.  The 14 smallest minimum annual sea ice extents have all occurred in the past 14 years.

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Earth just had its hottest September on record

Photo, posted September 2, 2020, courtesy of Tim Vrtiska via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Shrinking Ice In The Bering Sea | Earth Wise

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The Bering Sea forms the divide between the two largest landmasses on Earth:  Eurasia and the Americas.  Recent analysis of vegetation from a Bering Sea island has determined that the extent of sea ice in the region is the lowest it has been for over 5,000 years.

St. Matthew Island, a small island in the middle of the Bering Sea, has essentially been recording what is happening in the ocean and atmosphere around it, in the form of the composition of peat layers on the island.  By analyzing the chemical composition of peat core samples, scientists can estimate how sea ice in the region has changed over the course of time.

Changes in the relative amounts of two oxygen isotopes in the sediment and plant debris trapped in the peat on the island reflect the nature of precipitation during the period when the peat layers formed.  That ratio is correlated with the amount of sea ice in the region.  Satellite data acquired over the past 40 years confirms this correlation.

Analysis of the data shows that the current ice levels are unprecedented in the last 5,500 years.  These long-term findings affirm that reductions in Bering Sea ice are due to more than recent higher temperatures associated with global warming.  Atmospheric and ocean currents, which have also been altered by climate change, play a large role in the presence of sea ice.

Summertime sea ice in the Arctic was expected to reach its second-lowest extent in September in 40 years of observation.  Sea ice typically builds up again each winter, but the changes in ice extents actually lag behind changes in greenhouse gas level by decades.  Future ice loss is already built into the system.

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Bering Sea ice extent is at most reduced state in last 5,500 years

Photo, posted December 2, 2012, courtesy of Bering Land Bridge National Preserve via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Hot July | Earth Wise

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The numbers are in and, unsurprisingly, July was a hot month.  July 2020 tied for the second-hottest July on record for the planet, according to the National Oceanic and Atmospheric Administration.  In our own backyard, the Northern Hemisphere saw the hottest July ever, breaking the previous record set just last year.

The July 2020 global temperature was 62.06 Fahrenheit, which is 1.66 degrees above the 20th-century average.  The combined land and ocean surface average temperature for the Northern Hemisphere, the highest ever recorded for July, was 2.12 degrees F above average, breaking the previous record by 0.14 degrees.

Record-hot July temperatures were also recorded across parts of southeastern Asia, northern South America, across the west and northern Pacific Ocean, the northern Indian Ocean, and parts of the Caribbean Sea.

The year-to-date global land and ocean surface temperature was the second highest in the 141 years of record keeping at 58.79 degrees Fahrenheit, which is 1.89 degrees F above the 20th-century average. 

So far it is been the hottest year to date on record across a large portion of northern Asia, parts of Europe, China, Mexico, northern South America, as well as the Atlantic, northern Indian and Pacific oceans.

Meanwhile, the extent of sea ice in the Arctic for July 2020 was the smallest ever measured in the 42 years of record-keeping, over 23% below the 1981-2010 average.  July’s Arctic sea ice extent was smaller than the previous record (set last year) by 120,000 square miles, an area roughly the size of New Mexico.

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July 2020 was record hot for N. Hemisphere, 2nd hottest for planet

Photo, posted July 24, 2018, courtesy of Maria Eklund Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Why The Arctic Is Warming So Fast | Earth Wise

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The Arctic has been warming at the fastest rate of any place on Earth.  There have long been observations of amplification of Arctic warming, meaning that its temperature increases have been well above what would be expected from the global temperature rise.

Many climate models have attributed this warming to the melting of sea ice.  As the bright white ice disappears for longer periods of the year, the dark surface waters that are exposed absorb sunlight rather than reflecting it back into space the way the ice does.  This is known as the ice-albedo feedback.  But it does not entirely explain the amount of warming in the Arctic.

Researchers at the Scripps Institution of Oceanography have developed a new theory that helps to explain what is going on.

In the areas of the Arctic Ocean where there is sea ice, the water is actually warmer at depth and colder near the surface.  The deeper waters are fed by the relatively warm Pacific and Atlantic Oceans while the surface water is cooled by the ice.  The increasing temperature difference between surface and deeper water causes a greater upward flow of heat.  This was first observed in research cruises that revealed evidence that the Arctic Ocean water was becoming more turbulent over time.

According to computer modeling, this phenomenon is responsible for about 20% of the amplification of global warming that occurs in the Arctic.

There are multiple ongoing studies looking at the Arctic warming trend.  Other factors that have contributed over time are the presence of chlorfluorocarbons in the atmosphere.   That contribution is waning since the use of CFCs has been phasing out over time.

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Researchers Find New Reason Why Arctic is Warming So Fast

Photo, posted April 19, 2017, courtesy of Markus Trienke via Flickr.

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.

Melting Permafrost | Earth Wise

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The Arctic is warming faster than any region on Earth and mostly we’ve been hearing about the rapid disappearance of Arctic sea ice.  But the land in the Arctic is also undergoing major changes, especially to the permafrost that has been there for millennia.

Permafrost occurs in areas where the temperature of the ground remains below freezing for two years or more.  About a quarter of the Northern Hemisphere’s landscape meets this criterion.  Most of the world’s permafrost is found in northern Russia, Canada, Alaska, Iceland, and Scandinavia.

Permafrost regions previously carpeted in cranberries, blueberries, shrubs, sedges, and lichen are now being transformed into nothing but mud, silt, and peat.  So-called regressive thaw slumps – essentially landslides – are creating large craters in the landscape.  (The Batagaika Crater in the Yana River Basin of Siberia is a kilometer long and 100 meters deep).

Apart from the violence being done to the Arctic landscape, the greatest concern is that the permafrost has locked in huge stores of greenhouse gases, including methane, carbon dioxide, and nitrous oxide.  It is estimated that the permafrost contains twice as much carbon as is currently contained in the atmosphere.  As the permafrost thaws, these gases will be released.  With them will be pathogens from bygone millennia whose impact cannot be predicted.  Climatologists estimate that 40% of the permafrost could be gone by the end of the century.

As the permafrost thaws, the region’s ecosystems are changing, making it increasingly difficult for subsistence indigenous people and Arctic animals to find food.  Landslides are causing stream flows to change, lakes to suddenly drain, seashores to collapse, and water chemistry to be altered.

The warming Arctic is about much more than disappearing sea ice.

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How Thawing Permafrost Is Beginning to Transform the Arctic

Photo, posted February 9, 2017, courtesy of the U.S. Geological Survey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

What’s On Nature’s Calendar? | Earth Wise

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The Inuit Calendar is based on six seasons defined by weather, ice, animal migration, daylight hours and the night sky.  All these variables are in flux according to Harvard Narwhal Biologist Dr. Martin Nweeia.  Last August in the high Canadian Arctic, at 72 degrees north latitude, temperatures were at an astounding 70 degrees during the day. In 2018, the same region at the same time of year, experienced one of the coldest August months in 15 years.  

Disappearing sea ice in Hudson Bay affects migration patterns of ice-dependent species like narwhal and beluga whales and now allows more shipping traffic which produces more marine noise pollution and the risk of an oil spill. As a natural resource, the Arctic has significant deposits of iron ore, gold, diamonds, phosphate, and bauxite, so cargo shipments are increasing yearly.  

The disappearance of caribou herds and altered migrations of other animals have also blurred the seasonal changes. Caribou numbers have decreased by more than half in the last two decades.  Narwhal populations are remaining steady but are experiencing migration shifts resulting in their appearance at new locations and their absence from traditional areas.  Even the timing of the migration has changed, shifting two weeks later from normal late summer – early fall patterns.  

The night sky, which has long had identifiable reference points for Inuit observers, is also changing causing speculation about changes in the magnetic field and a polar shift or flipping of the poles. The earth’s magnetic north has been shifting toward Siberia at an alarming 30 miles each year since 2015.  Every million years, it is estimated that the poles flip three times.  No one knows if or when it will happen again. That’s a calendar with some unexpected dates. 

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–Earth Wise acknowledges script contribution from Dr. Martin Nweeia of Harvard University.

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Migratory Tundra Caribou and Wild Reindeer

Earth’s magnetic field is acting up and geologists don’t know why

Photo, posted June 27, 2014, courtesy of the Bureau of Land Management via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Cooling The Earth With A Warmer Arctic | Climate Change | Earth Wise

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Researchers are considering a wide range of approaches to mitigate the effects of global climate change.  Among these are various strategies of geoengineering, which must be viewed with enormous caution, given the high likelihood of unintended consequences from almost anything we might do.

Researchers at the International Institute for Applied Systems Analysis have investigated potential strategies for cooling the planet in the absence of Arctic sea ice.

The Arctic region is heating up faster than any other place on earth and its sea ice is rapidly disappearing.  Estimates are that summer sea ice in the Arctic Ocean will be largely gone within a generation.  Arctic ice and snow reflect the sun’s energy into space, which helps to keep the planet cool.  What happens if that ice is gone?

The researchers explored the fact that the Arctic Ocean ice actually insulates the Arctic atmosphere from the warmer water under the ice.  Without the ice layer, the surface water would actually increase air temperatures by 20 degrees C during the winter.  That in turn would increase the heat irradiated into space and thereby cool down the planet.

The Arctic sea ice is in part maintained because the upper regions of the Arctic Ocean have lower salinity than the Atlantic Ocean.  This stops Atlantic water from flowing above the cold Arctic waters.  So, if we were to somehow deliberately increase the salinity of the Arctic Ocean surface water, warmer, less salty Atlantic Ocean water would flow in, increase the temperature of the Arctic atmosphere, and release heat trapped in the ocean into space.

It all sounds pretty crazy, but the researchers say that given the seriousness of climate change, all options should be considered when dealing with it.

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Could we cool the Earth with an ice-free Arctic?

Photo, posted August 19, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Another Hot November

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This past fall saw yet more of the high temperatures the world has been experiencing in recent times.  Both the season (September through November) and the year to date were the second hottest in recorded history.  November itself was the second-hottest November in the 140-year global climate record.

The high temperatures were felt at both ends of the world.  Sea ice coverage across both the Arctic and Antarctic oceans fell to near-record lows in November.  Arctic sea ice coverage was nearly 13% below the 1981-2010 average, while Antarctic coverage was 6.35% below average.

The average global land and ocean surface temperature for November was 1.66 degrees Fahrenheit above the 20th century average.  The year-to-date global temperature was 1.69 degrees Fahrenheit above the 20th century average.  These numbers correspond to almost a 1-degree Celsius increase, which should be compared with the Paris Climate Accord goal of keeping that increase to no more than 1.5 degrees.

November was the hottest November on record for South America, Africa, and the Hawaiian Islands.  The Caribbean had its second-hottest November, and Europe had its seventh hottest on record.

The world’s average sea surface temperature ranked second warmest for the year to date and was only 0.05 degrees cooler than the all-time record.

The National Oceanic and Atmospheric Administration issues monthly global climate reports and for quite some time, these reports seem to all be the same.  Another new record for heat or at least another near record.  We have to expect that this trend will continue at least until the world starts making progress in dealing with its root cause.

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November 2019 was 2nd hottest on record for the planet

Photo, posted July 20, 2016, courtesy of Salehin Chowdhury via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The March Of The Penguins Toward Extinction

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According to a new study from the Woods Hole Oceanographic Institution, the warming climate may render emperor penguins extinct by the end of this century.  The study, which was part of an international collaboration between scientists, finds that emperor penguins will likely experience an 86% decline by 2100 if the global climate continues to warm at the current rate.  At that point, it would be very unlikely for them to recover, according to the study’s lead author.       

The research was funded by the National Science Foundation and recently published in the journal Global Change Biology.

The fate of emperor penguins is largely tied to the fate of sea ice.  The penguins use sea ice as a place for breeding, feeding, and molting.  They look for very specific conditions of sea ice – it must be locked in to the Antarctic shoreline but also close enough to open seawater to give them access to food. The study predicts that this sea ice will gradually disappear, depriving the birds of their habitat, food sources, and ability to raise their young.     

The researchers combined two existing computer models to study three different climate change scenarios.  If the average global temperature increases by only 1.5 degrees Celsius, the study found that only 5% of sea ice would be lost by 2100, resulting in a 19% drop in penguin colonies.  If the planet warms by 2 degrees Celsius, the sea ice loss nearly triples and more than a third of penguin colonies disappear.  The ‘business as usual’ scenario where the planet continues to warm at the current rate will ensure a near complete loss of emperor penguin colonies by 2100. 

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Unless warming is slowed, emperor penguins will be marching towards extinction

Photo, posted January 15, 2011, courtesy of Eli Duke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The ‘Biggest Ever’ Arctic Expedition

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The Arctic is warming faster than any other region on Earth.  In fact, it’s warming at a rate of almost twice the global average.  And, since what happens in the Arctic doesn’t stay in the Arctic, the world is already feeling the effects: rising sea levels, changes in climate and precipitation patterns, increasing severe weather events, and so on. 

As a result, researchers from more than a dozen countries have launched the biggest and most complex expedition ever attempted in the Arctic.  They plan to freeze Germany’s largest research vessel, the Polarstern, into Arctic sea ice, where it will remain trapped for twelve months.  The ship will drift with the sea ice as the sea ice drifts.  The vessel will serve as a research laboratory, hosting a rotating crew of 300 scientists.  The ice, the ocean, the atmosphere, and even the wildlife will all be sampled.  This year-long journey will give researchers their closest look at how the polar climate and its fragile ecosystems are changing. 

Led by the Alfred Wegener Institute for Polar and Marine Research in Germany, the Multidisciplinary drifting Observatory for the Study of Arctic Climate project (or MOSAiC) is expected to cost about $150 million. 

One major goal of MOSAiC is to improve strikingly uncertain climate projections for the Arctic.  Climate models disagree on how much more the Arctic will warm as the concentration of greenhouse gases in the atmosphere rises and sea ice shrinks.  Some project a 5ºC rise by 2100 relative to the 1986-2005 average.  Others predict a 10ºC increase. 

Understanding the complex processes occurring in the Arctic is essential for projecting the future impacts of climate change. 

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Climate scientists prepare for largest ever Arctic expedition

Climate change: Polarstern leaves for ‘biggest ever’ Arctic expedition

Image courtesy of the U.S. Department of Energy Atmospheric Radiation Measurement (ARM) user facility.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Harsh Winters

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In recent years, there have been some unusually harsh winters in North America and Central Europe. This past January, the Midwestern US experienced extreme cold temperatures. We have all become familiar with the term ‘polar vortex’ and its role in sending cold air to middle latitudes and it is generally agreed that unusual behavior by the jet stream is the primary cause of the extreme winter weather.

For years, climate researchers around the world have been investigating the question as to whether the increasingly common wandering of the jet stream is a product of climate change or is a random phenomenon associated with natural variations in the climate system.

The jet stream is a powerful band of westerly winds over the middle latitudes that push major weather systems from west to east.  These days, the jet stream is increasingly faltering.  Instead of blowing along a straight course parallel to the equator, it sweeps across the Northern Hemisphere in massive waves, producing unusual intrusions of Arctic air into the middle latitudes.

Atmospheric researchers at the Alfred Wegener Institute in Germany have now developed a climate model that can accurately predict the frequently observed winding course of the jet stream.  The breakthrough combines their global climate model with a new machine learning algorithm on ozone chemistry.  Using their new combined model, they can now show that the jet stream’s wavelike course in winter and subsequent extreme weather outbreaks are the direct result of climate change.  The changes in the jet stream are to a great extent caused by the decline in Arctic sea ice, according to the results of the investigations.  The results are not surprising but there is now a detailed model to support the hypothesis.

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A warming Arctic produces weather extremes in our latitudes

Photo, posted January 11, 2011, courtesy of Carl Wycoff via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rapid Antarctic Melting

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The Ross Ice Shelf in Antarctica is the world’s largest ice shelf, covering an area roughly the size of France.  Scientists have spent several years building up a record of how the northwest sector of the enormous ice shelf interacts with the ocean beneath it.  Their results show that the ice is melting much more rapidly than previously thought because of in-flowing warm water.

In general, the stability of ice shelves is thought to be mostly influenced by their exposure to warm deep ocean water.  But the new research has found that surface water heated by the sun also plays a crucial role in melting ice shelves.

The interactions between ice and ocean water that occur hundreds of meters below the surface of ice shelves have a direct impact on long-term sea level.  The Ross Ice Shelf stabilizes the West Antarctic ice sheet by blocking the ice that flows into it from some of the world’s largest glaciers.

When ice shelves collapse, the glaciers that feed them can speed up by a factor of two or three.  None of the collapsing shelves in the past have come anywhere close to the size of the Ross Ice Shelf, which is more than 100 times bigger.

The new study by New Zealand’s National Institute of Water and Atmospheric Research showed that sun-heated surface water flowing into the cavity under the ice shelf near Ross Islands caused melt rates to nearly triple during the summer months.  This indicates that the loss of sea ice resulting from climate change is likely to increase melt rates in the future.  While the Ross Ice Shelf is still considered to be relatively stable, the new findings show that it may be more vulnerable than previously thought.

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Rapid melting of the world’s largest ice shelf linked to solar heat in the ocean

Photo, posted February 15, 2009, courtesy of Alan Light 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...)