At Glacier’s End: Protecting Glacial Rivers in Iceland
“Page after page of curving colorful rivers delight the eye in At Glacier’s End, a recently published book about Iceland’s glacial river systems. The images that lie behind its cover were created by Chris Burkard, a photographer and explorer, and the more than 8,000 words that tell their story were penned by Matt McDonald, a storyteller and traveller.”
“Our main goal with the book was to advocate for Iceland’s national parks and to try to create a voice for them from a visual perspective,” Burkard said in an interview with GlacierHub. “In Iceland, it’s really surprising, many politicians who are the decision-makers haven’t had a chance to actually see [these places] because they are far away and really hard to access.”
Seabirds Find New Ways to Forage in a Changing Arctic
“On Arctic landmasses, valley glaciers––formally known as tidewater glaciers––run all the way to the ocean, where cloudy plumes from their discharge create the perfect foraging habitat for seabirds. Researchers found some birds are reliant upon the turbid, subglacial freshwater discharge, which breaks apart icebergs and forms a column of freshwater foraging ground at the glacier’s edge, while others prefer to forage near the broken sea ice where water is less turbid…In 2019, Bungo Nishizawa and associates published a study in the ICES Journal of Marine Science that investigated the effects of subglacial meltwater on two assemblages of seabirds in northwestern Greenland.”
Read the full story by GlacierHub writer Audrey Ramming here.
A First-ever Look at Ice Stream Formation
In this week’s Video of the Week, the world gets its first-ever look at ice stream formation. The video, which was published on the American Geophysical Union’s (AGU) YouTube channel on December 17, tracks the rapid movement of the Vavilov Ice Cap, in the high Russian Arctic, from summer 2015 to summer 2018. In the video the glacier’s speed is color-coded by meters per day of movement in what scientists believe is the first documented transition of a glacial surge to a longer-lasting flow known as an ice stream.
On Arctic landmasses, valley glaciers––formally known as tidewater glaciers––run all the way to the ocean, where cloudy plumes from their discharge create the perfect foraging habitat for seabirds. Researchers found some birds are reliant upon the turbid, subglacial freshwater discharge, which breaks apart icebergs and forms a column of freshwater foraging ground at the glacier’s edge, while others prefer to forage near the broken sea ice where water is less turbid.
In 2019, Bungo Nishizawa and associates published a study in the ICES Journal of Marine Science that investigated the effects of subglacial meltwater on two assemblages of seabirds in northwestern Greenland. One group included foraging surface feeders like the black-legged kittiwake. The other was comprised of divers, like the little auk. The researchers found that while the surface feeders congregate in the area of the cloudy plume, divers prefer to search for food where the water is less cloudy, spatially dividing the bird groups near the edges of glaciers.
Françoise Amélineau, a researcher of seabird ecology at the Norwegian Polar Institute, published a study in Scientific Reports last year, presenting the results of a 12-year monitoring program in East Greenland, which analyzed biological parameters of the little auk, the most common seabird in the Atlantic Arctic. Amélineau says that little auks use vision to detect prey and because meltwater plumes are so cloudy, the birds tend to forage farther offshore in clearer water, where they dive more than 20 meters below the surface.
A 2013 study in Polar Biology noted that little auks inhabiting West Spitsbergen, Norway also preferred to forage in clear water, far from glacier fronts, where they could easily identify water masses containing large, energy-rich prey.
Little auks usually feed in cold waters at the edge of sea-ice, up to 150 km away from their colonies. “In our Greenland study, we looked at sea ice concentration because some of the prey consumed by little auks are sympagic (associated to the sea ice),” said Amélineau, and “the little auks performed shallower dives in the presence of sea-ice, probably to feed on ice-associated amphipods”––a small type of crustacean. However, these ice-covered feeding areas are disappearing as the climate warms, which could make foraging more difficult.
Not only does a warming Arctic affect the presence of sea ice, it also alters the distribution of the little auk’s prey. Little auks feed on large zooplankton, which remain at depth in clearer waters. As the Arctic warms, the smallest (and lower calorie) Atlantic species of zooplankton is extending northward, threatening the range of the two larger (and higher calorie) Arctic species that little auks prefer. The invasion of the small zooplankton has the potential to negatively affect the fitness and breeding success of the little auk, which is thought to have the highest metabolic rate of all seabirds due to its small size and large flying and diving range.
With sea ice disappearing, the fate of little auk survival may be at risk. However, little auks from a colony of Franz Josef Land, located in the Russian Arctic, are actually taking advantage of a glacial meltwater plume––an adaptation that could be crucial. “We show that in Franz Josef Land, little auks have changed their foraging behavior with sea-ice retreat and the increase of glacier meltwater volume. At this site, they foraged at the glacier meltwater front instead of at more distant feeding grounds near the sea-ice because it allowed them to make shorter foraging trips,” Amélineau told GlacierHub.
Amélineau explained that “at the glacier front, zooplankton is stunned by cold and osmotic shock at the boundary between glacier melt and seawater, which makes it easier for little auks to catch. It probably concentrates their prey closer to the colony, but according to Nishizawa’s study, if the turbidity of the water is too high, meltwater plumes become unfavorable foraging areas for little auks who use vision to detect prey.” Discharge mechanisms can differ between glaciers, and this may be why little auks are able to utilize the Franz Josef Land differently than in Greenland, Amélineau added.
Black-legged kittiwakes are the most common type of gull in the world. While they do consume large zooplankton and small crustaceans, they mainly prefer to eat small fish and other marine invertebrates. While they are the only type of gull that dives and swims underwater, they make very shallow dives compared to that of the little auk, and are unhindered by turbid water.
Turbid subglacial discharge, which is unloaded 10-100 meters beneath the surface of the water, upwells at glacial fronts to form plumes that bring zooplankton, as well as marine worms and jellies from depth to the water’s surface. “The foraging behaviour of kittiwakes observed in the tidewater glacier bays revealed them to be swarming over the subglacial discharge, with rapid simultaneous nose-diving and plunging into the surface water in pursuit of rising prey,” according to one study in Scientific Reports.
While the size of meltwater plumes at glacial fronts are increasing with climate warming in the Arctic, apparently benefitting surface feeders, it is also important to consider the stage of glacial retreat. Kittiwakes, as well as other surface feeders, benefit most from deep tidewater glacier bays because they have strong discharges that upwell prey to the surface over a wide area.
According to the IPCC, the Arctic is warming twice as fast as the rest of the world. “While other species may be able to shift their distribution to higher latitudes or altitudes,” Amélineau said, “Arctic species may not find suitable habitat anymore.”
This is both ecologically and culturally concerning.
While little auks are ecologically considered a keystone species in the Arctic, they are also culturally important to the Indigenous peoples that live there. “They are hunted in Greenland,” Amélineau told GlacierHub. The Inuit “prepare a food called kiviak, where the little auks are fermented for 3 months in a seal skin!” Approximately five hundred of these birds are stuffed, whole, into the skin, and left in a pile of stones to ferment over the winter. They are a popular treat on weddings and birthdays.
Biological responses to changing climatic conditions are difficult to predict, particularly in remote locations that are already heavily impacted like the Arctic, where the ecosystem is already impacted by ongoing sea-ice decline and warming. Amélineau says this makes long-term seabird monitoring efforts extremely important, especially as these birds can be seen as ‘sentinels’ of what will happen at lower latitudes.
A team of scientists on board a former Danish fisheries research ship and icebreaker is working to measure changes to Helheim glacier and the fjords around it. Helheim, named for the world of the dead in Norse mythology, is one of Greenland’s largest outlet glaciers. This means that it is one of the primary locations for meltwater leaving the Greenland ice sheet. It is responsible for 4% of Greenland’s annual mass loss.
Understanding the melting at Helheim is crucial because Greenland has the potential to contribute 27cm of sea level rise within the lifetimes of today’s children.
The project studies Helheim using several technologies in pursuit of the team’s goal to create complex models of glacial fracturing. Some of the methods being used to collect data include drilling into the glacier to determine how much snow is deposited on the glacier during storms, using seismometers to detect the spread of concealed fractures, and checking the status of the glacier’s terminus four times daily with an automatic laser system to monitor calving, among other sources of information.
To learn more about the study check out this article from Science Magazine which our video of the week draws from.
World Meteorological Organization says sea level rise accelerating, fed by land ice melting
From the World Meteorological Organization: “The amount of ice lost annually from the Antarctic ice sheet increased at least six-fold, from 40 Gt per year in 1979-1990 to 252 Gt per year in 2009-2017.
The Greenland ice sheet has witnessed a considerable acceleration in ice loss since the turn of the millennium.
For 2015-2018, the World Glacier Monitoring Service (WGMS) reference glaciers indicates an average specific mass change of −908 mm water equivalent per year, higher than in all other five-year periods since 1950.”
The “dramatically changing landscape” of Mer de Glace
From New Scientist: “About a century ago, women with boaters and parasols sat near the Montenvers train station above the glacier, which then was almost level with a tongue of jagged ice snaking into the distance. Today, visitors are greeted by a slightly sad and largely grey glacier that is about 100 metres lower.”
An interdisciplinary analysis of changes in the high Andes
From Regional Environmental Change: “The high tropical Andes are rapidly changing due to climate change, leading to strong biotic community, ecosystem, and landscape transformations. While a wealth of glacier, water resource, and ecosystem-related research exists, an integrated perspective on the drivers and processes of glacier, landscape, and biota dynamics is currently missing. Here, we address this gap by presenting an interdisciplinary review that analyzes past, current, and potential future evidence on climate and glacier driven changes in landscape, ecosystem and biota at different spatial scales.
Our analysis indicates major twenty-first century landscape transformations with important socioecological implications which can be grouped into (i) formation of new lakes and drying of existing lakes as glaciers recede, (ii) alteration of hydrological dynamics in glacier-fed streams and high Andean wetlands, resulting in community composition changes, (iii) upward shifts of species and formation of new communities in deglaciated forefronts,(iv) potential loss of wetland ecosystems, and (v) eventual loss of alpine biota.”
Greenland and Iceland have been periodically reshaped by megafloods over thousands of years, a new paper in the journal Earth-Science Reviews has revealed.
British research duo Jonathan Carrivick
and Fiona Tweed have
provided the first evidence of gargantuan Greenlandic floods and extensively
reviewed the record of comparable events in Iceland. The researchers set out to
better understand what constituted a megaflood and find traces of them recorded
in the landscapes of these icy islands.
In media stories and even within the scientific literature the authors found that terms like “catastrophic flood,” “cataclysmic flood,” and “super flood” have been used indiscriminately and interchangeably. There are, however, strict definitions associated with each. A “catastrophic flood,” for instance, occurs when peak discharge exceeds 100,000 cubic meters per second — more than 18 times greater than the flow over Niagara Falls. Multiply that by ten (i.e. 1,000,000 cubic meters per second) and you get a sense of what constitutes a true megaflood.
Despite expressly seeking records of megafloods in the landscape
and literature, Carrivick and Tweed found that a more practical approach was to
identify events with “megaflood
attributes.” Scientists have recorded very few true megafloods since
those that cascaded off the Laurentide Ice Sheet, which
once mantled much of North America in the aftermath of the Last Glacial Maximum. While
there have been few recent floods that exceed one million cubic meters per
second, there have been several with comparable erosive power and lasting
Shaped by water
In Greenland, Carrivick and Tweed found 14 sites where huge floods had rampaged down fjords and across expansive “sandur,” or outwash plains. These have typically been outbursts from ice-dammed lakes, which have periodically unleashed inconceivably vast volumes. The glacial lake Iluliallup Tasersua empties every five to seven years and has a capacity of more than six cubic kilometers of water. At its peak, that flow would drown New York City’s Central Park in a column of water deeper than four Empire States Buildings.
Iceland, too, has experienced
its fair share of monstrous floods. Many of them have were triggered by
volcanic eruptions. Due to the unique setting of Iceland, where the active
fire-breathing mountains of the Mid-Atlantic island are blanketed with ice caps
and glaciers, erupting magma invariably explodes into the underside of a
quenching ice mass. This interaction, more often than not, results in an outburst
flood known locally as a “jökulhlaup,”
which produces tremendous amounts of power that is capable of reshaping and
inundating the island’s plains.
The region surrounding Öræfajökull, one of the most active
volcanoes in Iceland, is infamous for having suffered from devastation wrought
by both fire and ice.
“After it erupted in 1362, the
whole area was renamed as ‘Öræfi,’ which means ‘The Wasteland,” Tweed told
GlacierHub. “They renamed the area because it had been inundated by a grey
sludge, hyper-concentrated flow deposits and volcanic ash which had eradicated
the farmland and rendered it unusable.”
The eruption was the largest in Europe since Vesuvius immortalised
the communities of Pompeii and Herculaneum in AD79. The floodwaters rushed out
at over 100,000 cubic meters per second — qualifying as a “catastrophic flood.” The torrent was
so powerful that it was able to transport rocks weighing 500 metric tons, each
equivalent to four and a half blue whales. Despite not strictly meeting the
definition of a megaflood, the event certainly bore many of the hallmarks of
But the impacts of such deluges are not limited to their power to remold centuries-old landforms, toss about house-sized chunks of ice, or transport a beach-worth of sediment in a matter of hours.
Outbursts in Greenland can release as much as six billion metric tons of water within a matter of 7-10 days. This rapid draining of a glacier-lake basin radically changes the pressure atop the ice sheets, causing isostatic rebound, which can result in fractured shorelines, as localized sections of coast re-expand.
Water from an outburst flood often passes through a highly pressurized network of conduits within, beneath, and alongside ice. This can trigger a “seismic tremor.” So-called “glacier-derived seismicity” has been measured via seismometers since the early 2000s and experienced by eye-witnesses in the vicinity of Grænalón, one of the most famous jökulhlaup systems in Iceland. The authors note that while these events can be detected and felt, there is negligible impact from them.
Consequences for communities and corporations
Glacier floods also impact the communities living in the shadow of ice. Carrivick and Tweed’s previous work revealed that Iceland has experienced at least 270 glacier outburst floods across 32 sites, killing at least seven people. This makes Iceland among “the most susceptible regions to glacier floods” — and the economic costs that often result.
Icelanders are well acquainted with the natural dangers. Volcanic
eruptions, floods, and other geohazards are signature characteristics of their
Looking to the future, Tweed said: “We can expect to have jökulhlaups for another 200 years, until the ice
Such dire flood predictions are unlikely to rattle the stoic
Icelanders, who are more liable to fear the prospect of an Iceland bereft of
In even less populous Greenland, with people rarely situating
themselves in known flood paths, the impacts appear to be less disastrous. That
said, Carrivick noted: “When these big
outburst floods go into the fjords, and move out of the fjords and up and down
the coasts, you get these visible sediment plumes.”
The influx of sediment and freshwater changes the temperature,
salinity, and turbidity of the water in a fjord and the nearby ocean, which can
drive fish out the region. “It
basically shuts down the fishing industry for a couple of days at least,” Carrivick
Yet longstanding industries are not the only ones exposed to
the fickleness of Greenland’s glacier outbursts. As the ice sheet melts, a
number of resources are being eyed by extractive industries. Carrivick
recounted meeting teams of Swiss experts who had been commissioned by
Australian mining companies to set up rigs and conduct mineralogical
investigations in deglaciating regions.
He also remarked on the prospects of the hydropower industry, which has taken advantage of booms in other nations, like Nepal. “It might be an exaggeration, but I think it’s goldrush time,” he said. Regulators, he added, might struggle to keep up with monitoring and mitigating environmental impacts.
Whatever the future holds for Iceland and Greenland, Carrivick and Tweed’s research advances significantly scientific knowledge of the history of flooding on these two islands and makes a strong case for remaining attentive to the changes occurring on their diminishing ice masses.
“The extent of pre-Columbian land use and its legacy on modern ecosystems, plant associations, and species distributions of the Americas is still hotly debated. To address this gap, we present a Holocene palynological record (pollen, spores, microscopic charcoal, SCP analyses) from Illimani glacier with exceptional temporal resolution and chronological control close to the center of Inca activities around Lake Titicaca in Bolivia. Our results suggest that Holocene fire activity was largely climate-driven and pre-Columbian agropastoral and agroforestry practices had moderate (large-scale) impacts on plant communities. Unprecedented human-shaped vegetation emerged after AD 1740 following the establishment of novel colonial land use practices and was reinforced in the modern era after AD 1950 with intensified coal consumption and industrial plantations of Pinus and Eucalyptus. Although agroforestry practices date back to the Incas, the recent vast afforestation with exotic monocultures together with rapid climate warming and associated fire regime changes may provoke unprecedented and possibly irreversible ecological and environmental alterations.”
“Politicians have tussled for years over the fate of the Tongass, a massive stretch of southeastern Alaska replete with old-growth spruce, hemlock and cedar, rivers running with salmon, and dramatic fjords. President Bill Clinton put more than half of it off limits to logging just days before leaving office in 2001, when he barred the construction of roads in 58.5 million acres of undeveloped national forest across the country. President George W. Bush sought to reverse that policy, holding a handful of timber sales in the Tongass before a federal judge reinstated the Clinton rule.
“The Programme for Monitoring of the Greenland Ice Sheet (PROMICE) has measured ice-sheet elevation and thickness via repeat airborne surveys circumscribing the ice sheet at an average elevation of 1708 ± 5 m (Sørensen et al. 2018). We refer to this 5415 km survey as the ‘PROMICE perimeter’ (Fig. 1). Here, we assess ice-sheet mass balance following the input-output approach of Andersen et al. (2015). We estimate ice-sheet output, or the ice discharge across the ice-sheet grounding line, by applying downstream corrections to the ice flux across the PROMICE perimeter.”
Temperature records fell one after another in Europe last week with five countries—Great Britain, Belgium, the Netherlands, Germany, and Luxembourg—registering record highs.
A study conducted by World Weather Attribution concluded that temperatures during the hot spell would have been 1.5-3 degrees Celsius cooler if not for the additional warming brought about by human-caused climate change.
Video posted to Twitter shows how rising temperatures are impacting Europe’s alpine glaciers. Severe-weather.EU posted footage of a massive mudslide barreling down a mountainside on July 28th at the height of the heat wave. The group alleges the mudflow was brought about by melting glaciers in Mauvoisin, Switzerland.
A mudflow from the melting glaciers in Mauvoisin, Switzerland yesterday, July 28th. Thanks to Ilyes Ghouil for the report! Source: @Météo Franc-comtoise pic.twitter.com/SnSskjkD7A
The high pressure system that parked over Europe and brought about the record heat has since moved north, where it’s led to potentially record-breaking melt across Greenland’s ice sheet.
The familiar images of temperature anomalies that are produced by the world’s climate and weather agencies have inspired Philadelphia, Pennsylvania-based artist Diane Burko, who is currently working on a painting depicting the July heatwave in Europe.
From GlacierHub writer and environmentalist Tsechu Dolma: “China is hosting World Environment Day 2019, its mounting environmental crisis is endangering hundreds of millions and downstream nations, what happens on the Tibetan plateau has profound consequences on rest of Asia.”
Everest traffic jam blamed for climber deaths
From the New York Times: “Climbers were pushing and shoving to take selfies. The flat part of the summit, which he estimated at about the size of two Ping-Pong tables, was packed with 15 or 20 people. To get up there, he had to wait hours in a line, chest to chest, one puffy jacket after the next, on an icy, rocky ridge with a several-thousand foot drop.
This has been one of the deadliest climbing seasons on Everest, with at least 11 deaths. And at least some seem to have been avoidable.”
From Frontiers of Earth Science: “Kangerlussuaq Glacier is one of Greenland’s largest tidewater outlet glaciers, accounting for approximately 5% of all ice discharge from the Greenland ice sheet. In 2018 the Kangerlussuaq ice front reached its most retreated position since observations began in 1932. We determine the relationship between retreat and: (i) ice velocity; and (ii) surface elevation change, to assess the impact of the retreat on the glacier trunk. Between 2016 and 2018 the glacier retreated ∼5 km and brought the Kangerlussuaq ice front into a major (∼15 km long) overdeepening. Coincident with this retreat, the glacier thinned as a result of near-terminus acceleration in ice flow. The subglacial topography means that 2016–2018 terminus recession is likely to trigger a series of feedbacks between retreat, thinning, and glacier acceleration, leading to a rapid and high-magnitude increase in discharge and sea level rise contribution. Dynamic thinning may continue until the glacier reaches the upward sloping bed ∼10 km inland of its current position. Incorporating these non-linear processes into prognostic models of the ice sheet to 2100 and beyond will be critical for accurate forecasting of the ice sheet’s contribution to sea level rise.”
In this Video of the Week, watch an aerial view of the flow line at the Jakobshavn Glacier, in Ilulissat, Greenland. The video was posted on Twitter by Santiago de la Peña of Ohio State University’s Byrd Polar and Climate Research Center.
“This behemoth shreds into the ocean the equivalent of San Francisco’s water consumption,” he said.
Jakobshavn glacier is well known for likely producing the iceberg that sunk the Titanic.
It is also a very dynamic glacier. In the early 2000s, Jakobshavn was one of the fastest-flowing glaciers in the world, losing up to 20 meters in height each year. It is estimated that between 2000 and 2010, Jakobshavn alone contributed almost 1 millimeter to global sea level rise. In more recent years, however, Jakobshavn is actually growing again, now gaining about 20 meters in height per year.
Researcher Santiago de la Peña of Ohio State University’s Byrd Polar and Climate Research Center posted video on Twitter of raging streams of meltwater carving through the surface of Greenland’s Russell Glacier.
“Early May and melt season is already in full swing in western Greenland,” he wrote. “The amount of meltwater at Russell glacier for this time of year is staggering.”
The glacier is located on the west coast of Greenland.
Peña studies ice sheet dynamics and surface mass balance in Greenland and Antarctica.
In several tweets following his video of Russell Glacier, Peña described high temperatures and large amounts of meltwater.
“We serviced 2 stations at an elevation of 2300m and 1900m; the lower site was above freezing, the other at -4C. They are usually in the -20s and -30s this time of the year,” he wrote in a May 6 tweet.
From Geomorphology: “Ahora Gorge is a 400 m deep canyon located along the North Eastern flank of Mt. Ararat (Turkey), a compound volcanic complex covered by an ice cap. In the past, several diarists and scientific authors reported a calamitous event on July 2, 1840, when a landslide triggered by a volcanic eruption and/or an earthquake obliterated several villages located at the foot of the volcano. The reasons and effects of this Ahora Gorge Catastrophe (AGC) event have been obscure and ambiguous. To reappraise the 1840 catastrophe and the geomorphic evolution of the Ahora Gorge, we used high-resolution satellite images, remote sensing thermal data supplemented by observations collected during two field surveys.”
Albedo Effect in the Swiss Alps
From The Cryosphere: “Albedo feedback is an important driver of glacier melt over bare-ice surfaces. Light-absorbing impurities strongly enhance glacier melt rates but their abundance, composition and variations in space and time are subject to considerable uncertainties and ongoing scientific debates. In this study, we assess the temporal evolution of shortwave broadband albedo derived from 15 end-of-summer Landsat scenes for the bare-ice areas of 39 large glaciers in the western and southern Swiss Alps. […] Although a darkening of glacier ice was found to be present over only a limited region, we emphasize that due to the recent and projected growth of bare-ice areas and prolongation of the ablation season in the region, the albedo feedback will considerably enhance the rate of glacier mass loss in the Swiss Alps in the near future.”
Glacier Meltwater Impacts in Greenland
From Marine Ecology Progress Series: “Arctic benthic ecosystems are expected to experience strong modifications in the dynamics of primary producers and/or benthic-pelagic coupling under climate change. However, lack of knowledge about the influence of physical constraints (e.g. ice-melting associated gradients) on organic matter sources, quality, and transfers in systems such as fjords can impede predictions of the evolution of benthic-pelagic coupling in response to global warming. Here, sources and quality of particulate organic matter (POM) and sedimentary organic matter (SOM) were characterized along an inner-outer gradient in a High Arctic fjord (Young Sound, NE Greenland) exposed to extreme seasonal and physical constraints (ice-melting associated gradients). The influence of the seasonal variability of food sources on 2 dominant filter-feeding bivalves (Astarte moerchi and Mya truncata) was also investigated. Results revealed the critical impact of long sea ice/snow cover conditions prevailing in Young Sound corresponding to a period of extremely poor and degraded POM and SOM.”
In this week’s Video of the Week, watch a massive glacier calving event that occurred at Helheim Glacier in Greenland. The video was captured on 22 June 2018 by Denise Holland of New York University.
The calving event took place over a 30-minute time period, and was sped up into a time-lapse of about 90 seconds. During this time span, over four miles of the glacier’s edge broke off, flowing into one of the fjords that connects Helheim Glacier to the ocean. To put this in perspective, a calving event of this size would measure roughly the size of lower Manhattan, all the way to Midtown in New York City. In a warming world, glacier calving is a large force contributing to global sea-level rise.