A new animation of Pine Island Glacier calving events in Antarctica demonstrates the immense power of nature. Adrian Luckman, a satellite imaging glaciologist, produced the GIF that shows not one, but three Antarctic calving events occurring between June 2017 and February 2020. The latest event represented in the animation occurred on February 9 of this year. GlacierHub reported on the lead up to this event in October 2019, after the European Space Agency released a video showing huge cracks in the glacier. The rapid retreat Pine Island Glacier has experienced in recent years has drawn significant attention, which includes a 2018 article published on GlacierHub that highlighted the ice loss experienced by the glacier.
Following the first two calving events illustrated in Luckman’s GIF, the icebergs that broke off from the glacier can be seen moving out into the ocean over many months. Given the recent occurence of the February event, such movements cannot yet be shown. As a result, the GIF provides just a glimpse of the third calving event.
The last recorded calving event from the Pine Island Glacier left icebergs floating in Pine Island Bay off the west coast of Antarctica. According to the Earth Observatory at NASA, the largest iceberg that broke off during the February 2020 event is nearly twice the size of Washington, DC. The monstrous iceberg born this year was named B-49 by the U.S. National Ice Center, which is now tracking the iceberg’s movement. The U.S. National Ice Center is an agency operated by the U.S. Navy, Coast Guard, and NOAA, which provides environmental intelligence to the federal government.
Pine Island Glacier calving events have increased in frequency in recent years. NASA reports that these events used to take place on four to six year intervals, however, calving of the glacier has become a yearly occurrence. The increase in these events is indicative of the warming water in Pine Island Bay. The relatively warm water is melting the glacier from below, causing the ice shelf to thin and calving to occur. The glacier is also among those experiencing the fastest retreat in Antarctica.
The calving events depicted in the GIF produced by Luckman are just three from a series that according to the U.S. National Ice Center began in 2000. As the Pine Island Glacier continues to thin, there are likely to be more occurrences. Luckman shares many videos, animations and observations with his Twitter followers. Follow him @adrain_luckman to stay up to date.
Discoveries of microbes locked within the depths of glacial ice are opening an exciting new frontier for scientific research, while also posing an ecological predicament. As climate change causes ice masses to melt worldwide, the re-emergence of ancient bacteria and viruses threatens present day species lacking immunity to these old world pathogens.
Early this year, researcher Zhi-Ping Zhong and a team of researchers discovered 33 viral populations within two ice cores that had been extracted from the Guliya ice cap in the northwestern part of the Tibetan Plateau, in the Kunlun Mountains of northwestern China. The ice dates as far back as 15,000 years ago. All but five of the viral groups are new to science, and about half were predicted to have infected different strains of bacteria, which were also abundant in the ice.
The Tibetan Plateau is a vast, high altitude arid grassland home to species like the snow leopard, Tibetan wolf, and wild yak. It is surrounded by some of the world’s highest mountain chains including the Himalayas, the Qilian and Kunlun mountains, and the Karakoram range of northern Kashmir. Shadowed by the world’s two highest peaks, Mount Everest and K2, at an elevation that averages over 4,500 meters, the Tibetan Plateau is known to many as “the roof of the world.”
To climate scientists, however, the Tibetan Plateau and its crown of peaks is known as “The Third Pole,” since it is home to tens of thousands of glaciers containing the world’s largest non-polar reservoir of ice. These glaciers feed the most renowned Asian rivers, including the Yangtze, Yellow, Mekong, and Ganges which stretch thousands of kilometers into the arid regions of China and Pakistan and supply water to almost a third of the world’s population.
In their paper, which is currently circulating for comment in advance of peer-review, the researchers explain that the shallow plateau core was drilled in 1992 at a depth of 35 meters while the summit core was drilled in 2015 at a depth of 52 meters. The viral populations are quite dissimilar between the two ice cores and are also different at various depths, “presumably representing the very different climate conditions” at the time when the viral particles settled down into the snow to be compacted into ice.
Video from Kevin Bakker: Ice core drilling in Antarctica (circa 2009) for the purposes of studying bacterial community structure.
Though the first reports of microbes being found in glacial ice occurred in the early twentieth century, they were largely neglected until the 1980s when scientists began investigating organisms in an ice core from Vostok, in Eastern Antarctica. This discovery sparked a surge of glacier ice-core sampling at the end of the twentieth century. However, most studies focused on bacterial communities.
Kevin Bakker, an infectious disease modeler at the University of Michigan, studied bacterial community structure in Antarctic water and ice cores in 2008-09. Once his team extracted a core, it was melted down very slowly, “at the room temperature of the icebreaker we were on, so around 40-50 degrees Fahrenheit, to make sure the bacteria were kept alive,” Bakker said in an interview with GlacierHub. “Bacteria pop very easily,” he added, “and we needed them alive to see which organisms were eating the radioactive food we fed them… to see which bacteria were active in the community.”
But for viruses, the definition of whether they are living or not is a moot point, since the DNA/protein complex (while not technically living) simply takes over its host cell — which most of the time is a bacterium. Zhi-Ping Zhong’s team wrote, “information about viruses in these habitats is still scarce, mainly due to the low biomass of viruses in glacier ice and the lack of a single and universally shared gene for viruses,” which can be used for genome sequencing.
In fact, the authors wrote, “there are only two reports of viruses in glacier ice.” They include the Vostok study, as well as a study that found “tomato-mosaic-tobamovirus RNA in a 140,000-year old Greenland ice core.” Viral genomes from glacier ice have not been previously reported, and “their impacts on ice microbiomes have been unexplored.”
Moreover, prior to this study, no specific decontamination method existed. In an interview with Vice, Scott O. Rogers, a professor at Bowling Green State University, said “the biomass is so low that anything you contaminate it with on the outside is going to be at much higher concentrations than anything on the inside of the ice core.” Because it is easy to contaminate ancient microbes with modern ones, the researchers developed a new “ultra-clean” method for isolating pure samples from the ice cores.
The ice cores had been sealed in plastic tubing, covered with aluminum, and transferred at -20 degrees Celsius from the drilling sites to freezers in Lhasa, Beijing, Chicago, and finally to Byrd Polar and Climate Research Center at Ohio State University. In a sub-freezing temperature controlled room, researchers began extracting their samples by first shaving off half a centimeter from the outer contaminated layer of ice. The cores were then washed with ethanol to dissolve another layer, and finally sterile water was used to wash the final half centimeter away.
The pristine inner ice was then methodically melted down and filtered, and steps were taken to identify the virus after extracting the microbial DNA. The virus’s age could be determined by counting the ice layers, just as you would count rings in a tree. To be even more precise, the researchers also dated carbon and oxygen isotopes found in each ice layer.
Ancient microbes provide researchers a window into Earth’s evolutionary and climatic past. “We are very far from sampling the entire diversity of viruses on Earth,” Chantal Abergel, an environmental virology researcher at the French National Centre for Scientific Research, told Vice. Unfortunately, glaciers around the world are shrinking at an alarming rate. The Tibetan Plateau itself has lost a quarter of its ice since 1970, so the race is on to collect as much knowledge as possible with what’s left.
Despite its extreme altitude, the glaciers on the Tibetan Plateau are latitudinally situated to receive a great deal of sunlight, and like the other two, this third pole is warming faster than the global average. In the IPCC special report on the cryosphere, scientists warn that two thirds of its remaining glaciers are bound to disappear by 2100. “This will release glacial microbes and viruses that have been trapped and preserved for tens to hundreds of thousands of years,” wrote Zhi-Ping Zhong’s team.
“At a minimum, this could lead to the loss of microbial and viral archives that could be diagnostic and informative of past Earth climate regimes,” the researchers added. However, “in a worst-case scenario, this ice melt could release pathogens into the environment.”
This possibility is very real. Bakker pointed out that in 2016, the anthrax virus escaped from a frozen reindeer carcass, killing a 12-year old boy and hospitalizing about twenty others, when permafrost melted in the Siberian tundra. Frozen microbes released through ice melt are still able to reinfect their targets, but while “there are a ton of viruses, only a few actually infect humans,” Bakker explained. Most ancient viruses pose more of a risk to bacteria. Still, it is important not to underestimate the “dangers encased in ice,” Rogers warned in his interview with Vice.
Zhi-Ping Zhong’s study represents a major advance in the field of virology. It shows how frozen creatures can inform predictions about the types of microbes that may re-emerge with climate warming, and what this could potentially mean for the future of our biosphere.
Video from Kevin Bakker: Bakker’s research team encounters some friends on their scientific expedition in Antarctica in 2009. Perks of being a scientist!
If there is a ‘doomsday glacier‘ Thwaites Glacier in Antarctica is it. The massive glacier is one of the fastest melting glaciers in the world and has the potential to destabilize the entire West Antarctic ice sheet––a scenario which would raise global sea levels an average of ten feet.
A team of scientists led by David Holland and Keith Nicholls––from the International Thwaites Glacier Collaboration Project (ITGC)––are using hot water to drill holes through the glacier. On January 8 the first bore hole was drilled, opening a 590 meter access point directly to the bottom of the glacier.
The goal of the project––MELT––is to better understand how the warm water is melting the glacier at the grounding line. Ultimately, researchers hope the data gleaned will allow the glacier’s potential sea-level contribution to be more accurately predicted.
On Twitter, the handle @HotWaterOnIce is actively providing updates from Thwaites’ surface, providing an on-ice view of the depth and breadth of the research taking place.
The Lamont-Doherty Earth Observatory (LDEO) is a part of the Earth Institute at Columbia University where roughly 200 PhD researchers and 90 graduate students are involved in earth-science research. “Its scientists study the planet from its deepest interior to the outer reaches of its atmosphere, on every continent and in every ocean, providing a rational basis for the difficult choices facing humanity.”
Miriam Cinquegrana, administrative coordinator at LDEO, has initiated a series of photo exhibits “to provide a space for members of the Lamont community to explore their passion for photography and to share their artistic work.” The hope is for these individuals to make connections and engage their research in new ways, noted Cinquegrana. Previous landscape exhibits have included Patagonia and Easter Island, as well as The Aleutians.
The newest exhibit, Antarctica, is the third display to feature photos taken by scientists as they perform their research in the field. Pieces from this exhibit are displayed here, and highlight photos taken by the following scientists: Isabel Cordero, Nick Frearson, Jonathan Kinslake, David Porter, Margie Turrin, Martin Wearing, Carson Witte, and Robin Bell.
“Each year Lamont scientists travel the globe with their research. This exhibition provides a small glimpse into the beauty and fragility that is Antarctica. These images were taken by Lamont Scientists as they went about their daily research studying topics as diverse as ice dynamics to tectonic origins and ranging from the Antarctic Peninsula to the Ross Ice Shelf and beyond into the East Antarctic interior.”
Trump administration proposes logging in Alaska’s Tongass National Forest
From the Washington Post:
“The Trump administration Tuesday proposed allowing logging on more than half of Alaska’s 16.7 million-acre Tongass National Forest, the largest intact temperate rainforest in North America.
President Trump instructed federal officials to reverse long-standing limits on tree cutting at the request of Alaska’s top elected officials, on the grounds that it will boost the local economy. But critics say that protections under the “roadless rule,” finalized just before President Bill Clinton left office in 2001, are critical to protecting the region’s lucrative salmon fishery and tourism operations.
The U.S. Forest Service said it would publish a draft environmental impact statement this week (Oct. 15) that, if enacted, would exempt the Tongass from the 2001 roadless rule.”
New cracks observed in Antarctica’s Pine Island Glacier
From the European Space Agency:
“The Copernicus Sentinel-1 and Sentinel-2 satellites have revealed new cracks, or rifts, in the Pine Island Glacier—one of the primary ice arteries in the West Antarctic Ice Sheet. The two large rifts were first spotted in early 2019 and have each rapidly grown to approximately 20 km in length.
Mark Drinkwater, Head of the Earth and Mission Sciences Division at ESA, says, ‘These new rifts appeared very soon after last year’s major calving of iceberg B46. Sentinel-1 winter monitoring of their progressive extension signals that a new iceberg of similar proportions will soon be calved.'”
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.”
What Happens to Species Diversity as Glaciers Melt?
Published in July 2019, a study looked at the effects of melting glaciers on seafloor species diversity in Antarctica.
As glaciers melt, more sediment is released into the surrounding waters and can smother seafloor communities. As part of the same process, more icebergs are created which can scrape the bottom of the ocean, removing the top layers of sediment, known as soft sediment.
Soft sediment contains a great deal of life and plays an important role in marine ecosystems The study explains that it is one of the “key components of energy flow through food webs” and is important “in sedimentary processes especially nutrient and carbon cycling, waste breakdown and removal.”
The authors wrote that it was “the first study to comprehensively analyse the composition of Antarctic soft sediment metazoan communities across all size classes, from < 1 mm up to 10 cm, in two geographically distinct coves.”
The study found that “in contrast to findings from rocky substrata, there was no evidence of an effect of typical Antarctic stressors of iceberg scour and intense seasonality. As at other latitudes, organic content of the sediment was most strongly correlated with community structure, suggesting that increased sedimentation from run-off from melting glaciers may be the main climate change effect on these communities.”
Credit rating agency buys climate risk firm
A New York Times article explains the credit rating agency Moody’s purchase of Four Twenty Seven, a firm that measures climate risk:
“Sudden shocks such as floods, wildfires or storms can hurt businesses and send residents fleeing, taking away the tax revenue that governments use to pay their debts. And longer-term threats — such as rising seas or higher temperatures — can make those places less desirable to live in, hurting property values and, in turn, the amount raised by taxes.
Rating agencies translate those risks, along with more traditional factors such as a government’s cash flow and debt levels, into a credit rating, which communicates to investors the odds that a government will be unable to repay its bondholders. Lower ratings generally mean that borrowers need to offer investors a higher return to account for that risk.
Following a string of deadly hurricanes and wildfires in 2017, Moody’s, along with S&P Global and Fitch Ratings, issued reports warning state and local governments that their exposure to climate risk could affect their credit ratings.”
Alaskan glacier podcast
In a 25 minute podcast, Manasseh Franklin describes her experience following the water from a glacier in Alaska to the sea. She “wanted to make the melting of glaciers more real to people through her writing. So on an Alaskan rafting trip, she followed water to its source.”
As my year of research on glacier dynamics and water security in Chile came to a close in December 2018, I started searching for ways to put my newfound knowledge to good use while also soaking up the Patagonian summer. Through a bit of finesse and luck, I found a glacier education and guiding position for a polar expedition cruise company called One Ocean Expeditions. I felt like I was walking in a dream as I boarded an ice class cruise ship departing from Ushuaia, Argentina.
Through the five trips I worked on earlier this year, I had the great fortune to visit and interpret a myriad of glaciers from the shallow coves of the Antarctic Peninsula to the deep labyrinth of the Chilean fjords. Each glacier told a unique story, but a common theme emerged that links them all. While these massive, flowing systems may humble us with their power and enormity, they are deeply sensitive to their surroundings and profoundly affected by human-induced climate change.
There were four sites in my travels from the Antarctic Circle (66°33’S) north to Santiago, Chile (33°25’S) that best illustrated this duality for me.
Wilkinson and Murphy Glaciers,
Crystal Sound, Antarctica
The sun peaked over the horizon as we crossed into the Antarctic Circle and washed an orange light over the endless whiteness of the Stefan Ice Piedmont and Wilkinson and Murphy Glaciers. I couldn’t ask for a more majestic first glimpse of Antarctica.
Stefan is a modest size for an ice piedmont, a term to describe a low-lying expanse of ice that gradually slopes from the edge of a mountain to the sea. In comparison, the Wilkinson and Murphy Glacier complex is quite large, serving as an outlet for the Antarctic Peninsula Ice Shelf through a network of multiple glacial valleys that converge to tumble down to the sea.
waded through a bay of asymmetrical, peculiar icebergs that rivaled the size of
our eight-story ship. Unlike the more uniformed, tabular icebergs we later
encountered, which had neatly separated from ice shelves, these icebergs likely
calved off Wilkinson and Murphy or a neighboring tidewater glacier.
Crystal Sound set the stage for Antarctica as a dreamy, vast-beyond-comprehension, and complex continent of ice—a place that feels other-worldly until you realize these calving glaciers and massive melting icebergs feed the same ocean we all share.
Avalanche and Astudillo Glaciers, Paradise
Moving north, Paradise Harbor proved to be my favorite stop on each trip. It offers the best of the Antarctic Peninsula in mid-summer—calm and beautiful scenery, feeding humpback whales, porpoising penguins, and playful seals. We would start the day with a hike from the Almirante Brown Argentine base to a gentoo penguin colony and up to a bluff with a sweeping view of the massive Avalanche and Astudillo Glaciers.
One of my colleagues commented that in the seven years she has visited Paradise Harbor, she’s witnessed Astudillo Glacier recede noticeably. I’m yet to find an up-to-date study that could corroborate or rebut this observation, but it would be consistent with the behavior of the glacier in the late 20th century—displaying a frontal recession from 1973 to 1989 to the LIMA observations in the early 2000s.
our days were tranquil, I wondered what the collapse of the Larsen B Ice Shelf,
just over the ridge, felt like here and what the break-up of the even larger
Larsen C Ice Shelf will bring.
Serrano Glacier, Cordillera Darwin
Ice Field, Chile
Although they were connected until about 40 million years ago, the Antarctic Peninsula and southern tip of South America today feel like two separate worlds. The hardy, dwarfed vegetation of the Cordillera Darwin is a wash of green in comparison to the Antarctic landscape, and the glaciers are smaller, more active, and radiate a rich blue hue.
Serrano is a northern-facing glacier deep in the Agostini Fjord and outlet for the Cordillera Darwin Ice Field, the third largest expanse of ice in South America. On a sunny and wind-free morning, we maneuvered closer to Serrano’s face and marveled at a thick medial moraine that traced up to the convergence of two upper branches of the glacier.
The Serrano Glacier, like the vast majority of glaciers in the region, is losing mass. Between 2000 and 2011, its area thinned at an average rate of about 1.0±0.4 meters of water equivalent per year and, overall, the Ice Field lost an average of -3.9±1.5 gigatons of ice per year.
struck me about Serrano is how gorgeous, massive, and storied it is, while
remaining practically anonymous—located in a region that few have even heard
of, Serrano is rarely visited or studied.
Pío XI Glacier, Southern Patagonia
Ice Field, Chile
In contrast, Pío XI, also known as Brüggen Glacier, is one of the most famous glaciers in South America. At a whooping 1,300 square kilometers, it is about as large as Los Angeles and is the biggest glacier on the continent—and one of the only that is advancing.
Between 1945 and 1995, Pío XI advanced 10 kilometers at speeds of up to 50 meters per day, paving over 400-year-old trees and sealing off the upper section of the fjord, which brought about the formation of a lake. It has since slowed considerably, as warmer temperatures have caused more precipitation to fall as rain instead of snow and its primary flow path has shifted from the south terminus to the north.
Scientists surmise that Pío XI surged, while its neighbors continued retreating, possibly because of high snow accumulation in its abnormally large basin, fjord-glacier interactions, elevated water pressure beneath the glacier, changes in geothermal activity, or sediment build-up at its terminus.
a famous and peculiar glacier, I could barely contain my excitement as we
cruised into Eyre Fjord and watched the gargantuan, blue mass come into focus from
the upper deck. I trailed behind Australian glaciologist Ian Goodwin with his
black beret and sharp goatee as we walked along Pío XI’s wide southern terminal
moraine and searched for the source of a sediment-rich stream gushing out from
the bottom of the glacier.
XI was unlike any other glacier we’d seen—the water was saturated with sediment
and free of icebergs, the face was a modest height and sloped away from us, and
we observed no calving events that day. The preposterous amount of sediment and
continuous purge of meltwater begged a closer look. We scribbled notes and took
pictures to report back to colleagues and pondered how we could return with a
A cryosphere in crisis
The recent headlines in Greenland remind us the cryosphere is changing faster than we can grasp. Our modeling and monitoring is more accurate than ever, but the general public is just beginning to understand the complexity and urgency of the issue.
I found that these cruises offered a powerful platform to connect with folks from across the political spectrum through an immersive and emotional crash course in glaciology. I’m not yet sure how, but there must be a way we can create equally moving but more accessible and sustainable educational opportunities. As I reflect comfortably at home, Wilkinson and Murphy, Avalanche and Astudillo, Serrano, and Pío XI continue to flow.
A consensus estimate for the ice thickness distribution of all glaciers on Earth
From Nature Geoscience: “Projections of future glacier change, estimates of the available freshwater resources or assessments of potential sea-level rise all need glacier ice thickness to be accurately constrained. Previous estimates of global glacier volumes are mostly based on scaling relations between glacier area and volume, and only one study provides global-scale information on the ice thickness distribution of individual glaciers. Here we use an ensemble of up to five models to provide a consensus estimate for the ice thickness distribution of all the about 215,000 glaciers outside the Greenland and Antarctic ice sheets.”
A risk assessment of the area surrounding the Popocatépetl volcano
From Geofísica Internacional: “In the areas of highest risk, 20 towns in Puebla State, 8 in México State, and 2 in Morelos State were evacuated; in areas of intermediate risk, also were evacuated 5 towns in México State, 1 in Puebla State, and 2 in Morelos State. In addition, the San Buenaventura Nealtican community in Puebla was evacuated, because it was in the lahar flow path along the Huiloac ravine, which originates on the north side of the volcanic cone, at the glacier which potentially could be eroded and melted by pyroclastic flows. “
Degradation of macroalgal detritus in shallow coastal Antarctic sediments
From Limnology and Oceanography: “The western Antarctic Peninsula is one of the fastest warming areas on Earth (Ducklow et al. 2007). As a result, its glaciers are melting and retreating at unprecedented rates (Rückamp et al. 2011; Cook et al. 2016). The retreat of glaciers opens up new habitat for marine benthic organisms (e.g., Lagger et al. 2018), such as sublittoral rocky substrates that are increasingly colonized by macroalgae (Quartino et al. 2013; Mystikou et al. 2014; Campana et al. 2018). Macroalgal communities play an important role in the Antarctic coastal ecosystem. They dominate shallow benthic communities on hard substrates along the western Antarctic Peninsula, often covering > 80% of the bottom, with standing biomass levels comparable to temperate kelp forests (Wiencke and Amsler 2012). A global average of 82% of the local primary production from kelp is estimated to enter the detrital food web where it can be exported to adjacent communities (Krumhansl and Scheibling 2012).”
Amid Antarctica’s vast stretches of glittering white snow and ethereal blue glacier ice is the famous Blood Falls. Situated at the terminus of Taylor Glacier in the McMurdo Dry Valleys, Blood Falls, which is an iron-rich, hypersaline discharge, spews bold streaks of bright-red brine from within the glacier out onto the ice-covered surface of Lake Bonney.
Australian geologistGriffith Taylor was the first explorer to happen upon Blood Falls in 1911, during one of the earliest Antarctic expeditions. At the time, Taylor (incorrectly) attributed the color to the presence of red algae. The cause of this color was shrouded in mystery for nearly a century, but we now know that the iron-rich liquid turns red when it breaches the surface and oxidizes––the same process that gives iron a reddish hue when it rusts.
The discharge from Blood Falls is the subject of a newstudy, published in the Journal of Geophysical Research: Biogeosciences, researchers sought to discern the origin, chemical composition, and life-sustaining capabilities of this subglacial brine. Lead author W. Berry Lyons of The Ohio State University and his co-researchersdetermined that the brine “is of marine origin that has been extensively altered by rock-water interactions.”
Researchers used to believe that to be that Taylor Glacier was frozen solid from the surface to its bed. But as measuring techniques have advanced over time, scientists have been able to detect huge amounts of hypersaline liquid water at temperatures that are below freezing underneath the glacier. The large quantities of salt in hypersaline water enable the water to remain in liquid form, even below zero degrees Celsius.
Seeking to expand on this recent discovery, Lyons and his co-researchers conducted the first direct sampling of brine from Taylor Glacier using the IceMole. The IceMole is an autonomous research probe that clears a path by melting the ice that surrounds it, collecting samples along the way. In thisstudy, the researchers sent the IceMole through 17 meters of ice to reach the brine beneath Taylor Glacier.
The brine samples were analyzed to obtain information on its geochemical makeup, including ion concentrations, salinity, and other dissolved solids. Based on the observed concentrations of dissolved nitrogen, phosphorus, and carbon, the researchers concluded that Taylor Glacier’s subglacial environment has, along with high iron and sulfate concentrations, active microbiological processes––in other words, the environment could support life.
To determine the origin and evolution of Taylor Glacier’s subglacial brine, Lyons and his co-researchers pondered other studies’ conclusions in comparison to their results. They decided the most plausible explanation was that the subglacial brine came from an ancient time period when Taylor Valley was likely flooded by seawater, though they did not settle on an exact time estimate.
In addition, they found that the brine’s chemical composition was much different than that of modern seawater. This suggested that as the brine was transported throughout the glacial environment over time, weathering contributed to significant alterations in the chemical composition of the water.
Thisstudy provides insights not only for subglacial environments on Earth but also potentially to other bodies within our solar system. Seven bodies, including Europa (one of Jupiter’s moons), Enceladus and Titan (two of Saturn’s moons), Pluto, and Mars are thought to harbor sub-cryospheric oceans.
Lyons and his co-researchers concluded that this subglacial brine environment likely is conducive to life. The ability of sub-cryospheric environments such as this one to support life on Earth hints at an increased possibility of finding life in similar environments elsewhere in our solar system.
This week’s Roundup covers discovery of what causes the reddish tint of “Blood Falls,” the Taylor Glacier’s terminus in Antarctica, a bill passed by the US Senate that could protect glaciers in North Cascades National Park, and ICIMOD’s newly published Hindu Kush Himalaya Assessment.
Scientists Determine the Geochemistry of Antarctica’s Blood Falls
From Journal of Geophysical Research: Geosciences: “Blood Falls is a hypersaline, iron‐rich discharge at the terminus of the Taylor Glacier in the McMurdo Dry Valleys, Antarctica…Our results provide strong evidence that the original source of solutes in the brine was ancient seawater, which has been modified with the addition of chemical weathering products.”
Good News for Glaciers in North Cascades National Park
From the National Parks Traveler: “Strong bipartisan support in the U.S. Senate has reauthorized the Land and Water Conservation Fund, protected Yellowstone and North Cascades national parks from mining on their doorsteps, designated some 1.3 million acres of wilderness, and called for a study into potential units of the National Park System, though the House of Representatives still needs to take up the measure.”
Assessing the Value of the Hindu Kush Himalaya
From ICIMOD: “This assessment report establishes the value of the Hindu Kush Himalaya (HKH) for the 240 million hill and mountain people across the eight countries sharing the region, for the 1.65 billion people in the river basins downstream, and ultimately for the world. Yet, the region and its people face a range of old and new challenges moving forward, with climate change, globalization, movement of people, conflict and environmental degradation. At the same time, we also see incredible potential to meet these challenges in a sustainable manner.”
Collapsing Glaciers in The Himalaya–Hindu Kush mountain ranges & the Tibetan Plateau
From Nature: “Tibetan communities are dealing with the impacts of collapsing glaciers. In October 2018, debris dammed the Yarlung Tsangpo River, which forms the headwater of the Brahmaputra, threatening areas as far afield as Bangladesh with flooding.”
From Ecological Applications: ” In this study, we describe contrasting responses to an apparent regime shift [in food particle size] of two very different benthic communities in McMurdo Sound, Antarctica. We compared species-specific patterns of benthic invertebrate abundance and size between the west (low productivity) and east (higher productivity) sides of McMurdo Sound across multiple decades.”
Read more about the changes to benthic invertebrates in Antarctica here.
Resilient Mountain Solutions in the Hindu Kush Himalaya
From UNFCCC: “Research at ICIMOD has revealed that temperatures in the mountains have increased significantly faster than the global average, and are projected to increase by 1–2°C on average by 2050. Precipitation patterns and water availability are likely to change.”
Read more about Resilient Mountain Solutions such as vulnerability reduction and improved ecosystem services here.