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Shrinking Glaciers And Methane | Earth Wise

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The Arctic region is warming much faster than the rest of the planet.  In fact, according to a study published last year in the journal Nature, the Arctic has been warming nearly four times faster than the rest of the globe during the last 43 years.  This rapid warming is leading to substantial reductions in sea ice, thawing of permafrost, shifts in wildlife populations, and changes in ocean circulation patterns, among other changes. 

According to new research recently published in the journal Nature Geoscience, shrinking glaciers in the warming Arctic are exposing bubbling groundwater springs, which could provide an underestimated source of methane, a potent greenhouse gas.  Methane is more than 25 times as potent as carbon dioxide at trapping heat in the atmosphere.

The study, which was led by researchers from the University of Cambridge and the University Centre in Svalbard, Norway, found large sources of methane gas leaking from groundwater springs unveiled by melting glaciers. 

As glaciers retreat in the Norwegian archipelago of Svalbard and leave behind newly exposed land, groundwater beneath the Earth seeps upward and forms springs. In 122 out of the 123 springs studied, the research team found that the water was highly concentrated with dissolved methane.  When the spring water reaches the surface, the excess methane can escape to the atmosphere. 

Researchers are concerned that additional methane emissions released by the Arctic thaw could dramatically increase human-induced global warming.  If this phenomenon in the Svalbard archipelago is found to be more widespread across the Arctic — where temperatures are quickly rising and glaciers melting — the methane emissions could have global implications. 

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The Arctic has warmed nearly four times faster than the globe since 1979

Shrinking Arctic glaciers are unearthing a new source of methane

Photo, posted October 22, 2022, courtesy of David Stanley 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

Methane From Thawing Permafrost | Earth Wise

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The Arctic permafrost contains a massive amount of carbon in the form of frozen soil, which contains remnants of plants and animals that died millennia ago.  Estimates are that there is 2 ½ times as much carbon trapped in this Arctic soil than there is in total in the atmosphere today.

As the Arctic warms, the permafrost is starting to thaw.  Once that happens, microbes begin to consume the previously frozen organic matter trapped in the soil.  As part of this process, the microbes produce large amounts of methane, which is an extremely potent greenhouse gas.   Thus, there continues to be great concern that wide-scale thawing of the permafrost would result in massive amounts of methane being released into the atmosphere.

A recent study in northern Sweden revealed a glimmer of hope.  The study gauged methane emissions from a swath of permafrost that thawed in the 1980s and another that thawed 10 or 15 years later. 

In the first area, as ice melted underground, water on the surface sank down into the soil.  As the surface dried out, new plants emerged that helped to keep methane emissions buried underground.

Grasses found in wet areas have straw-like structures that convey oxygen to their roots.  The straws also allow methane in the soil to escape into the atmosphere.  As the areas dry out, other plants lacking the straws can sometimes replace the grasses.  When methane can’t escape, soil bacteria break it down into carbon dioxide.

The result is that the permafrost releases only a tenth of the methane as expected.  The hope is that changes in plant cover driven by climate change may limit methane emissions from thawing permafrost.

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Thawing Permafrost In Sweden Releases Less Methane Than Feared, Study Finds

Photo, posted July 7, 2014, courtesy of NPS Climate Change Response via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Beavers Are Flooding The Warming Arctic | Earth Wise

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The accelerating warming in the Arctic has transformed the region into a warmer, wetter, and more diverse environment.  Warming temperatures have encouraged the increasing growth of vegetation, particularly shrubs that provide beavers with bark to eat and branches to build with.  Warming temperatures also mean that lakes and streams freeze solid for shorter periods of time or not at all, allowing beavers to pursue their construction projects for longer periods during the year.

Prior to the mid-1970s, residents of the Alaskan Arctic encountered few beaver ponds.  In 2018, researchers using satellite imagery mapped 12,000 beaver ponds in Alaskan tundra.

Beavers are causing major changes in the streams and floodplains that many small Alaskan villages depend upon for food, water, and navigation.  As the rodents transform lowland tundra ecosystems, they are eliminating food sources, deteriorating water quality, and making it difficult to navigate waterways.

The migration of beavers across the Arctic landscape is largely a result of climate change.  But it is also becoming one of the factors amplifying climate change.  Scientists are trying to figure out the degree of permafrost thawing that beaver dam-and-den building is causing and how fast these defrosted organic soils will degrade and release trapped carbon and methane.

Beaver dams alter the hydrology of streams by slowing the flow, storing and spreading water to create wetlands, raising the water table, and lowering the oxygen content of the water. 

Climate-driven changes in species distributions affect human well-being as entire ecosystems continue to change.  Shifts in animal habitat stimulated by climate change could have profound consequences across the globe.

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Beavers Are Flooding the Warming Alaskan Arctic, Threatening Fish, Water and Indigenous Traditions

Photo, posted June 12, 2018, courtesy of Peter Pearsall/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Alaska Is Getting Wetter | Earth Wise

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Siberia has been in the news for record-setting heat waves and wildfires, but it is not the only northern region experiencing unusual weather.   Alaska, apart from setting its own warm weather records, is experiencing the rainiest five years in its century-long meteorological record.

Extreme weather in the Arctic is being driven by an aspect of climate change called Arctic amplification, which leads to temperatures rising faster than the global average.  The physical basis of Arctic amplification is well understood, but its effects over time are much less predictable.

The past five years included two summers with average precipitation, one that was a little drier than usual, and two of the wettest summers on record.    Researchers have taken measurements of how far below the surface permafrost has thawed by the end of summer over a wide range of Alaskan environments.

About 85% of Alaska sits upon permafrost and the increasing rainfall over the past five years is leading to a deeper thaw of permafrost across the state.  The wettest summer on record was 2014 and permafrost didn’t freeze back to previous levels even when the next couple of summers were relatively drier.

The study demonstrated how different types of land cover govern relationships between summer rainfall and permafrost thaw.  As Alaska becomes warmer and wetter, the vegetation cover is projected to change, and the increasing occurrence of wildfires will disturb larger areas of the landscape.  These conditions are likely to lead to a feedback loop driving more and more permafrost thawing.

Fundamental changes to Alaskan ecosystems are occurring on an unprecedented timescale – not gradually over decades or lifetimes, but over mere months or years.

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Alaska is getting wetter. That’s bad news for permafrost and the climate.

Photo, posted June 10, 2011, courtesy of Peter Rintels via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

More Carbon Dioxide From Thawing Permafrost | Earth Wise

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The Arctic is warming much faster than the rest of the planet.  Stories about the loss of polar ice and hundred-degree temperatures in Siberia have become commonplace.  One of the most troubling aspects of the warming Arctic is the thawing of permafrost.  Permafrost is ground that remains frozen for at least two years; some of it has been frozen for tens or hundreds or even thousands of years.  Found under a layer of soil, permafrost is composed of rock, soil, sediments, and varying amounts of ice.  It stores the carbon-based remains of plants and animals that froze before they could decompose.  Permafrost covers almost a quarter of North America, but it is starting to thaw.

Scientists estimate that there are more than 16,000 billion tons of carbon locked away in Arctic permafrost, which is almost double the amount of carbon that is currently in the atmosphere.  Climate models predict that the warming of the Arctic could lead to 5 to 15% of that carbon to be emitted as carbon dioxide by the year 2,100, which would be enough to raise global temperatures by 0.3 to 0.4 degrees Celsius.

New research has increased this estimate because it includes a key pathway for CO2 to enter the atmosphere that earlier models ignored.   When carbon from thawing permafrost escapes into Arctic lakes and rivers, it is oxidized by ultraviolet and visible light and it then escapes into the atmosphere as CO2.  This process is known as photomineralization and is estimated to raise permafrost-related CO2 emissions by 14%.

Recent studies project that with every 1-degree Celsius increase in temperature, 1.5 million square miles of permafrost could be lost through thawing.

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Climate Models Underestimate CO2 Emissions from Permafrost by 14 Percent, Study Finds

Photo, posted July 7, 2014, courtesy of NPS Climate Change via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Siberian Heat | Earth Wise

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Siberia has been experiencing unprecedented high temperatures in recent months.  May was the hottest May on record and temperatures in Siberia have stayed well above average for the past year.

On June 20, temperatures in the small Siberian town of Verkhoyansk hit 100.4 degrees Fahrenheit, which is a record-high temperature in one of the fastest-warming places in the world.  Average high temperatures in June reach 68 degrees.  Verkhoyansk sits on the Yana River in the Arctic Circle and, during the winter, is one of the world’s coldest towns.  In 1892, its temperature dropped to -90 degrees Fahrenheit.  And now there is hundred-degree heat above the Arctic Circle.

Siberia tends to experience large temperature swings month-to-month and year-to year.  But it is very unusual for temperatures to stay well over average over an extended period of time as they have for the past year.  According to climate scientists, the kind of temperature swings seen recently would only happen once in 100,000 years if it were not for climate change.

Siberia has seen raging wildfires and structural damage from thawing permafrost as its temperatures have stayed warmer than normal.  The prolonged Siberian heatwave is an alarming situation.

The Arctic is warming twice as fast as the rest of the Earth because of a process known as Arctic amplification.  The acceleration of the Arctic ice melt leads to a seasonal snow cover that isn’t as white.  It therefore absorbs more sunlight, which then leads to more warming.

The amplified warming of the Arctic with its increased melting of ice leads to higher sea levels, and not just in the Arctic Ocean.  With less Arctic ice to reflect sunlight, the world’s oceans continue to warm. 

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Temperatures in an Arctic Siberian town hit 100 degrees, a new high

Photo, posted December 7, 2014, courtesy of Olga Dudenko via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Hidden Source Of Arctic Carbon | Earth Wise

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Researchers from the University of Texas at Austin, the U.S. Fish and Wildlife Service, and Florida State University have published a paper presenting evidence of significant and previously undetected concentrations and fluxes of dissolved organic matter entering Arctic coastal waters.  The source of the organic matter is groundwater flow atop the frozen permafrost.  The groundwater moves from land to sea unseen, but the new research reveals that it carries significant concentrations of carbon and other nutrients to Arctic coastal food webs.

Globally, groundwater is important for delivering carbon and other nutrients to oceans, but in the Arctic, where much water is trapped in the permafrost, its role was thought to be minimal.  But the new research reveals that groundwater may be contributing an amount of dissolved organic matter to the Alaskan Beaufort Sea that is comparable to what comes from neighboring rivers during the summer.

The researchers found that shallow groundwater flows beneath the surface and picks up new, young organic carbon and nitrogen, but it also mixes with layers of deeper soils and thawing permafrost, picking up and transporting century-to-millennia old organic carbon and nitrogen.  This material is unique because it is directly transported to the ocean without seeing or being photodegraded by sunlight and may be valuable as a food source to bacteria and higher organisms that live in Arctic coastal waters.

The study concluded that the supply of leachable organic carbon from groundwater amounts to as much as 70% of the dissolved organic matter that enters the Beaufort Sea from rivers during the summer.  The role that groundwater inputs play in Arctic coastal ecosystems will be an area of active research for years to come.

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Hidden Source of Carbon Found at the Arctic Coast

Photo, posted June 14, 2015, courtesy of Eugen Marculesco via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving The Arctic Permafrost | Earth Wise

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Permafrost is frozen ground – a combination of soil, rock, sand, and ice – that remains at or below freezing for at least two consecutive years.  Approximately 25% of the land in the Northern Hemisphere meets this criterion, the majority of which can be found in northern Russia, Canada, Alaska, Iceland, and Scandinavia.

But as a result of the changing climate, these permafrost soils in the Arctic are beginning to thaw.  As they thaw, large quantities of greenhouse gases could be released, further accelerating climate change.  

A new study recently published in the journal Scientific Reports explores an unconventional countermeasure: resettling massive herds of large herbivores.  According to researchers from the University of Hamburg in Germany, herds of horses, bison, and reindeer could be used to significantly slow the loss of permafrost soils. 

During Arctic winters, the air temperature is often much colder than the permafrost.  Thick layers of snow can insulate the ground from the frigid air, keeping the permafrost warm (relatively speaking). But when the snow cover is scattered and compressed by the hooves of grazing animals, the insulating effect is reduced, which intensifies the freezing of the permafrost.

If climate change continues unchecked, the research team expects permafrost temperatures to rise 3.8-degrees Celsius.  This would result in half of the world’s permafrost thawing by the year 2100.  But in contrast, researchers found that the permafrost would only warm by 2.1 degrees Celsius with the resettled animals.  This 44% reduction in permafrost temperature would preserve 80% of the existing permafrost by 2100.

Natural manipulations of ecosystems could have tremendous results. 

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How horses can save the permafrost

Photo, posted July 17, 2012, courtesy of Kitty Terwolbeck 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.

The Arctic As A Carbon Source

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According to a new NASA-funded study, the Arctic may now be a source for carbon in the atmosphere rather than being the sink for it that is has been for tens of thousands of years.

The study, published in Nature Climate Change, warns that carbon dioxide loss from the world’s permafrost regions could increase by more than 40% over the next century if human-caused greenhouse gas emissions continue at their current pace.  Worse yet, carbon emitted from thawing permafrost has not even been included in most climate models.

Permafrost is the carbon-rich frozen soil and organic matter that covers nearly a quarter of Northern Hemisphere land area, mostly in Alaska, Canada, Siberia, and Greenland.  Permafrost holds more carbon than has ever been released by humans from fossil fuel burning, but it has been safely locked away by ice for tens of thousands of years.

As global temperatures rise, the permafrost is starting to thaw and release greenhouse gases into the atmosphere.

The recent findings indicate that the loss of carbon dioxide during the winter in the Arctic may already be offsetting carbon uptake during the growing season.  The researchers compiled on-the-ground observations of carbon dioxide emissions across many sites and combined these with remote sensing data and modeling.  They estimate that the permafrost region is now losing 1.7 billion metric tons of carbon during the winter season but taking up only 1 billion during the growing season.

The major concern is that as the Arctic continues to warm, more carbon will be released into the atmosphere from the permafrost region, which will further the warming.  Climate modeling teams across the globe are trying to incorporate these findings into their projections.

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Arctic Shifts to a Carbon Source due to Winter Soil Emissions

Photo, posted July 27, 2015, courtesy of Gary Bembridge via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Dangerous Diseases From The Past

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Climate change is poised to transform life on Earth as we know it.  The higher temperatures, the rising seas, the more frequent floods and droughts, among the countless other consequences associated with climate change, threaten to do irreversible damage to the world in the coming decades.

[Read more…] about Dangerous Diseases From The Past

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