Scientists Discover Networks of Lakes and Streams on Antarctica’s Ice Sheets

Image: University of Sheffield

|| April 22: 2017: University of Sheffield News || ά. Vast lakes and streams are widespread on the surface of Antarctica’s ice sheets according to new research published in Nature by an international team of scientists. The study, which included geographers from the University of Sheffield, has found that huge lakes have been forming on the surface of Antarctica since, at least, the 1940s and extensive networks of streams have been draining water onto vulnerable ice shelves, that are prone to collapse.

Scientists previously believed that the drainage of surface water, known as meltwater, was a rarity in Antarctica. However, the international team of researchers used aerial photography and satellite imagery to find that meltwater moves vast distances across the surface of the ice sheets onto ice shelves. Ice shelves, which are floating parts of ice sheets, are prone to collapse when water flows into their cracks and crevasses. The research team believes that in a warming climate, more water is likely to be produced on the surface of Antarctica, which could accelerate the ice sheets’ contribution to sea level rise.

Current predictions of sea-level rise do not include these processes. Dr Jeremy Ely, a member of the research team from the University of Sheffield’s Department of Geography, said, “If melted completely, Antarctica’s ice sheets contain enough water to raise global sea levels by around 58 metres, so it’s important that we understand how and where meltwater forms, moves, drains and the impact it can have on ice shelves, which can be prone to collapse.

Our study has found that extensive networks of lakes and streams have persisted in Antarctica for decades, which move surface water across its ice sheets onto ice shelves. One network of streams feeds a lake, which is situated at 85 degrees south, making it the most southern lake in the world.

Despite extensive studies in Greenland and observations of individual meltwater drainage systems in Antarctica, we previously had little understanding of how water moves across the surface of Antarctica’s ice sheets.”

The study, Widespread movement of meltwater onto and across the Antarctic ice shelves, is published in Nature on Thursday, April 20, 2017.

The research, also,  gives geography students at Sheffield access to the latest innovations in climate science. ω.

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Local Weather Impacts on the Melting of One of the Antarctica’s Fastest-Retreating Glaciers

The terminus of Taylor Glacier as seen from the helicopter. Photo by P. Neff.

|| February 19: 2017: University of East Anglia News || ά. Local weather plays an important part in the retreat of the ice shelves in West Antarctica, according to new research published in the journal Nature Communications. The study led by scientists at the University of East Anglia:UEA of the Pine Island Glacier:PIG used a unique five-year record to study how the interactions between the ocean and the atmosphere, as well as changing currents, control how heat is transported to, and beneath, the Pine Island Ice Shelf.

Pine Island Glacier is one of the fastest melting glaciers in Antarctica with some studies suggesting that its eventual collapse is almost inevitable. Previous research suggested more warm water was circulating under the ice shelf and melting it more rapidly, leading to an increasing contribution to sea level rise. However relatively little was known about what drives changes in ocean conditions in this remote part of Antarctica due to its inaccessibility. Some studies suggested that the ocean conditions close to Pine Island Glacier are influenced most strongly by winds at the edge of the continental shelf, some 400 km to the north, which in turn respond to changes in tropical ocean temperatures.

The study looked at the impact of shelf-edge winds and found this to be less direct than previously thought, and that local atmospheric conditions and ocean circulation are the main drivers of ocean temperature changes in the critical 350-700m depth range, over the period of observation.

Dr Ben Webber, oceanographer at UEA’s School of Environmental Sciences said, “The ice shelves of the Amundsen Sea – an area of the Southern Ocean – protect much of the West Antarctic Ice Sheet from collapse. These ice shelves are rapidly losing mass and understanding the mechanisms which control ocean conditions and drive melting of these glaciers is hugely important.

We found a strong annual cycle in the exchange of heat between the ocean and the atmosphere, which drives changes in ocean temperature. While these changes are less evident in deeper waters, through convection and mixing the heat can penetrate deeply enough to have a major impact on melting and influence the temperature of the water entering the cavity under the glacier.

There was a colder weather period from 2012-13, however, a separate study has shown that this only led to a partial slowdown of the glacier’s retreat, and many glaciers in the region have been retreating for decades and aren’t slowing down.”

Changes in the direction of the ocean currents also cause changes in temperature close to Pine Island Glacier. The colder period was associated with a reversal in the currents that transport heat into and around the bay.

Co-author Dr Povl Abrahamsen, Oceanographer at British Antarctic Survey, said, “Most of the ocean data around Antarctica are snapshots of conditions – and many areas are only visited once every one or two years, if that. A continuous five-year time series near Pine Island Glacier, one of the fastest-melting glaciers in Antarctica, lets us see what is happening between these snapshots, giving us insights into the processes driving the melting of Pine Island Glacier.”

Dr Webber continued, “It is likely that other ice shelves around Antarctica that are melting due to warm ocean conditions will also be strongly influenced by local atmospheric conditions. This would underline the importance of atmospheric and ocean monitoring close to the Antarctic coasts to give early warning of future changes in ice shelf melting and glacial retreat.”

The research was carried as part of the Natural Environment Research Council:NERC-funded iSTAR Programme and was in collaboration with US and Korean collaborators using data from ship-based and atmospheric observations including ship-deployed oceanographic moorings. ω.

‘Mechanisms driving variability in the ocean forcing of Pine Island Glacier’ is published in the journal Nature Communications - DOI: 10.1038/ncomms14507

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Madeleine Brasier Speaks of Antarctic Marine Worms and Her Collection of 20,00 Polychaetes Amounting to 400 species

Image: University of Liverpool

|| February 15: 2017: University of Liverpool News: Madeleine Brasier Writing || ά. Marine worms are some of the most abundant and diverse animals found on the Antarctic seafloor. They have many different ecological roles within marine communities making them an important part of ecosystem. To date we still do not fully understand how diverse our oceans are, especially regions, such as the deep Antarctic seafloor, which require research expeditions on ships such as the James Clark Ross to collect marine animals. Given the current and future environmental changes predicted in Antarctica, it is vital that we understand its biology if we want to monitor and manage any potential impacts.

My PhD aims to to re-examine the current levels of species diversity in Antarctic marine worms, describe their geographic distribution and determine their position within the Antarctic food web. To do this I have been using a combination of genetics, modelling and stable isotope analysis techniques. Whilst I am student at the University of Liverpool, my research project is joint with the Natural History Museum, London and the National Oceanography Centre, Southampton. My marine worms or ‘polychaetes’ which is Latin for ‘many bristles’, were collected on British Antarctic Survey led research expeditions to three different regions of Antarctica. In total about 20,00 polychaetes were collected amounting to 400 species based on their morphological characters.

The equipment, including nets and sledges, used to collect these worms and other animals is deployed from the ship, lowered to the seafloor which could be between 500 to 1500 m deep, where they are towed and slowly recovered. Once on deck we sort our samples, then carefully photograph and preserve our specimens before their journey back to our laboratories in the UK.

Using DNA I discovered the several of these species contained ‘cryptic species’ which are morphologically identical but genetically distinct. After sequencing nearly 500 individuals from about 15 species, we found that by using DNA species diversity increased by 233%.

Using a combination of species records, genetic data and particle tracking analyses we have observed that many of these small polychaete species are widespread throughout the western Antarctic or even circumpolar.  Understanding how species are distributed and connected is vital for marine management. In order to effectively protect marine regions, we need to be confident that the areas we are protecting contain a variety of marine species in abundance and are able to supply larvae or adults to neighboring regions.

The final stage of my PhD uses stable isotopes to determine the trophic level of Antarctic polychaetes, i.e. where they are in the food web. At the moment the relationship between species and functional diversity is not fully understood.

Most of our understanding of the feeding characteristics of these polychaetes is based on their morphology or related species from other oceans. Determining a comparable numerical trophic level we can examine the variation between and within cryptic species, Antarctic regions and depth ranges. Knowing whether species diversity relates to functional diversity will help us understand the impact of species loss on marine communities within the Antarctic Ocean.

I feel very lucky to have visited Antarctica twice during my PhD, in March 2016 I took part in a British Antarctic Survey expedition to the South Orkney Islands, just north of the Antarctic Peninsula. Here we sampled a marine protected area, collecting many species considered to be new to science and found many interactive relationships between several marine species.

I have recently obtained funding from Antarctic Science to study the functional relationship between deep-sea corals and symbiotic marine worms collected during the expedition.  Last summer I also attended the US Antarctic program’s early career-training course in Antarctic Biology at Palmer Station on the Antarctic Peninsula. Here I experienced what it was like to live and work on an Antarctic station and all the considerations, precautions and enjoyment involved in planning and conducting Antarctic research.

I will be submitting my thesis next year, after which I wish to continue my career in polar science, to improve our understanding of and help protect our oceans. ω.

Madeleine’s blog articles: Study the Antarctic Seafloor

And in Women in Polar Science

Madeleine Brasier is a PhD student in the University of Liverpool’s School of Environmental Sciences

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Satellites Track Variations in Antarctica’s Glacial Retreat

The terminus of Taylor Glacier as seen from the helicopter. Photo by P. Neff.

|| December 12: 2016 || ά. Five satellites spanning two decades have revealed variations in the timing and pace of glacial retreat in West Antarctica. Some glaciers’ thinning spreads up to three times faster than on neighbouring tributaries, and was offset by decades. The glaciers flowing into the Amundsen Sea have been drastically losing ice, likely due to rising sea temperatures recorded around Antarctica in recent decades.

The Pine Island Glacier is known to contribute more to rising sea levels than any other ice stream on the planet, and the neighbouring Thwaites and smaller Pope, Smith and Kohler Glaciers are also losing ice. But the rate at which these glaciers are melting varies between them, despite their relative vicinity. Possible reasons for this include differences in glacier catchment size, bedrock, topography and hydrology. What remains clear, however, is that over the past 25 years, all three have seen thinning from the grounding line, where the ice stream lifts up off the land and begins to float out over the ocean, across the glacier surface.

“Scientists generally agree that it is warm ocean water that melts the floating part of the glacier, which then allows the glacier to flow more easily because it’s no longer held back by the floating ice shelf. As the glacier flows faster, it starts to become thinner.” said Dr Hannes Konrad, lead author of the study published in Geophysical Research Letters. “If there’s not enough snow and ice accumulating higher up to compensate, the glaciers lose more and more of their mass as they flow towards the sea, and that’s exactly what we are seeing here, but the detail varies considerably between the three systems, and even within each glacier.”

Using data dating back to 1992 from the ERS-1 mission, together with information from ERS-2, Envisat, CryoSat and NASA’s IceSat, scientists from the UK’s Centre for Polar Observation and Modelling reconstructed surface heights along a series of glacial flowlines to see how thinning at the grounding lines had been passed further inland. In 1992, all three were already experiencing height loss at or near the grounding line, with Pine Island Glacier losing height by around 1 m every year – although the interior surface was stable.

Thinning then spread steadily, first up the glacier’s main trunk, and then further inland. While the pace at which it spread across the surface varied, rates of thinning reached up to 13 km:year.  Changes at Thwaites Glacier were more erratic. The surface at the grounding line was already falling by up to 03 m:year in 1992, but thinning ceased around 2000. In 2004, thinning continued and spread at similar rates to those seen at Pine Island Glacier, but the offset of about 10 years means that it did not spread as far inland.

The Pope, Smith and Kohler Glaciers experienced the largest falls in surface height of up to 7 m/year, most likely beginning before the data record. The thinning spread much more slowly than at Pine Island Glacier or Thwaites Glacier. “As well as being able to routinely monitor the polar ice sheets as a whole, these results show the ability of satellites to pinpoint how individual glaciers are responding to environmental change.” said CPOM Director Professor Andy Shepherd.

“The next steps are to refine our calculations of ice loss and sea level rise from the Antarctic ice sheet as a whole, and, in turn, improve our models of what might happen in the future.” The study is being presented today at the American Geophysical Union’s Fall Meeting held in San Francisco, USA.

ω.

If You are a Doctor and You Would Rather Leave Medicine to the Mortals and Go and Practise It Out There....In the Universe..... Apply

Map of Antarctica showing the 3200 m-high plateau called Dome-C in red square and
Concordia station, the star. Image: ESA:M. Drinkwater
 

|| November 28: 2016 || ά. The next medical doctor to spend a year at the Concordia research base in Antarctica arrived this week by aircraft. Carole Dangoisse from Belgium will live and work at the station conducting space research on and with the rest of the Italian–French crew as they spend the winter in isolation.

With temperatures as low as –80°C, no sunlight for four months and no access at all during the winter, Concordia is one of the most remote and isolated human outposts. Its unique location and extreme conditions offer ESA the chance to research how humans adapt to living far away from home – similar to an outpost in space or on another planet.  Carole will work on experiments looking at bone health, how the immune systems adapts to the extremes and how to assess mood in team dynamics, among others.

Knowing how someone feels is important for mission controllers. However, ask someone how they feel and they will never reply objectively. The Capa experiment will assess mood by analysing speech patterns such as tone of voice, intonation, use of grammar and speed of speech. Crewmembers will regularly record a video diary of their lives in Concordia as well as narrate a paragraph from a fairy tale.

By looking at changes in the way they talk into the camera and comparing these with results from standard questionnaires, researchers hope to develop software that can analyse speech automatically.

Carole is replacing Floris van den Berg, who has spent the last year in Antarctica. Floris is handing over the experiments to Carole and explaining the protocol as he prepares to leave next month.

ESA’s Jennifer Ngo-Anh explains, ''The research doctor in Concordia is like an astronaut on the International Space Station for ESA – she or he conducts experiments for the researchers in Europe and collects the results for analysis.”

ESA is looking for the next research doctor to run experiments in this unique setting. Do you have a medical degree and a sense of adventure? Sign up through the link to the right, an ESA member state nationality is required. ω.

And this is Dr Beth Healey, from London, England, UK, who, once upon a time, spent a year at Concordia.

What are on Dr Beth Healey's Eyes: Or Rather Were?

Released 07.06.2016 03:39 pm: Image: ESA:IPEV:PNRA: Beth Healey
 

|| June 08: 2016 || ά. Concordia sits on a plateau 3200 m above sea level. A place of extremes, temperatures can drop to –80°C in the winter, and the Sun does not rise above the horizon in the winter, forcing the crew to live in isolation without sunlight for four months of the year.

Its seclusion offers scientists a unique location to conduct research far from civilisation in many disciplines. The thin atmosphere, clear skies and zero light pollution around Concordia make it an ideal place for observing the Universe – as this picture shows with its aurora and many stars.

Auroras occur when atomic particles from the Sun hits Earth’s upper atmosphere, making it glow in a greenish blue light. They occur frequently over both polar regions, but are often difficult to see from populated areas.

For ESA, the isolation and extreme weather offer interesting parallels with spaceflight and living on another planet. Each year an ESA-sponsored medical doctor joins the crew of the Italian–French station to monitor and run experiments on the crew of up to 15.

This image was taken by Beth Healey, medical doctor from the winter of 2015. Timed to coincide with the opening of an exhibition on space and Antarctica, Beth is presenting the story “Step to the stars – our future in space starts on Earth”.

The narrative is featured in the WhiteSpace exhibition at the Times Science festival in Cheltenham, UK, being held June 07-12

What really happens in a crew of 13 isolated in a research station for nine months? Find out at. ω.

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Dearest Mother Earth, The Humanion Made You a Heart in Celebration of Your Joyous Bounty for Us

|| April 22: 2016 || This image, titled, Earth Humana, Heart Humana, made of two images:  the background image is taken, gratefully, from NASA and the centre image is made out of an ESA image ( with gratitude) in celebration of the Mother Earth Day 2016. Here, we give you, the Earth Humana Heart Humana. If you look at the top of the centre image where the light illumines almost two hearts of lights yet which could be imagined as the aortas of the heart made of waterfalls of lights coming outside to which you can imagine the two dark figures as a lion (larger one) and a lioness (the smaller one), a couple emerging from the dark to drink from that flooding waterfalls of lights. Having emerged into the absolutely beautiful exposition of the two hearts of lights they appear bedazzled and awed and just maintain that 'eternal' pose. 

Though the images from which this has been created, do not belong to us, this does to The Humanion for it is a creative product made of existing materials (with credit given to both NASA and ESA).

Anyone can use this image so long they follow the following:

Retaining the title of the image

Acknowledging that it is an image that has been taken from The Humanion

And acknowledging as we have done that it was created using two NASA/ESA images and these two organisations have no connection with The Humanion (or in your case) with you nor do they endorse The Humanion (or in your case) you or your organisation.

The image can only be used for bona fide purposes and can not be used in any commercial advertisement or party political purposes

And that you link this image to this page.

Thank you

Happy Mother Earth Day 2016

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The Real Ice Sheets of Antarctica

Laura Faye Tenenbaum Writing

The terminus of Taylor Glacier as seen from the helicopter. Photo by P. Neff.

||April 19, 2016: Climate NASA || “I’m looking at 10 glaciers and I’m sitting on one,” said Dr. Heidi Roop of the University of Rochester over satellite phone. “I’m looking at a landscape that’s been here for millions of years unaltered by people.” Roop had called me from Taylor Glacier, an outflow of the East Antarctic Ice Sheet, which flows down through Antarctica’s McMurdo Dry Valleys. I’m looking at a mountain that no human has ever touched, ever. This is a landscape where it feels like humans shouldn’t be. There are no animal trails, no trees. There’s rock and ice and us.”

Roop and the rest of the eight-person team, which included one driller, two scientists, three Ph.D. candidates and a camp cook/manager, had come to drill for ice cores at Taylor Glacier because of its unique configuration. Drilling ice cores is a technique climate scientists use to collect samples of trace gases such as carbon dioxide, methane and carbon monoxide that have been trapped in air bubbles in the layers of polar ice.

Air bubbles make up 10 percent of glacier ice. That may sound incredible, but it's true. In fact, teams of scientists spend entire careers studying these ice cores to learn about Earth’s atmosphere. In a traditional ice core, the ice is horizontally layered. The surface layer is the youngest, made of recent snow with modern atmosphere filling tiny spaces between snowflakes. Ice core science teams drill vertically down through time. The deeper you drill, the further back in time you go. (The deepest borehole, at Vostok, Antarctica, is more than 3,600 meters deep.) According to Dr. Peter Neff, a glaciologist who was also on the call, “We now have a very good understanding of past greenhouse gas concentrations because there’s been so much research since the 1990s, especially methane, for example. The signal of methane concentration is globally representative and we know from these ice cores the heartbeat of methane through the past 800,000 years with high accuracy.”

Scientists drilling for ice cores head to Antarctica because it’s the cleanest place on the planet. (There’s so much more pollution and dust in the Northern Hemisphere.) “We’re not studying Antarctica itself, although Antarctica is a huge player in the global climate system," Neff said. "But rather we’re learning things about global climate that we can learn only in Antarctica. It’s so far away, yet it holds clues that inform our understanding of the rest of the world.”

Travelling back in time

Taylor Glacier is an unusual place on a continent that’s full of the unusual, which is why this group of scientists traveled there. The glacier flow has essentially tipped ice layers on their sides, so to travel back in time the team can simply walk across the glacier instead of having to drill deep down. Time is stretched out north to south, so “as you walk northward you’re going forward in time, from ice that’s 80,000 years old, past the coldest part of the last glacial period 20,000 years ago (when it was so cold and dry there was less vegetation, so the atmosphere was dusty), all the way to ice that’s only 8,000 years old,” Neff explained. The team also took their Ski-Doo down the glacier about 10 kilometers to a site where they previously found 125,000 to 130,000 year old ice, which formed during the last interglacial period—the last time global climate was close to today’s warm temperatures. Other ice core records suggest that this time period was actually several degrees warmer than today, making it our best analogue for the warm conditions we’re headed towards.

Because the twists and folds of Taylor Glacier bring old ice to the surface, scientists only need to drill a few meters deep to collect very large samples from specific time periods. The team can core down into, say, the transition at the end of the last glacial period 20,000 years ago, when the climate system shifted back towards warmer temperatures—with some rapid climate change “speed bumps” along the way. The team hopes that gathering large enough samples of gases from this time period will help us understand what drives large climate shifts, what the real rates of change are and if we’re headed towards any tipping points. “We can ask more specific questions because we can get much bigger samples, which gives us room to unlock minute details in the chemistry of gases trapped in the ice,” Neff said. “For some work, we’re literally chain-sawing a meter down into the ice and breaking it out with a big metal bar and taking out samples that are a meter long by 30 centimeters wide that weigh like 250 pounds,” Roop added. “You should see my biceps right now.”

The view from the helicopter looking up Taylor Glacier. Taylor Glacier Camp is located about 15 km (about 9 miles) from the terminus, or end, of Taylor Glacier. Photo Credit: H. Roop.

24 hours of daylight

Although there is 24 hours of daylight during the summer in Antarctica, the drill team wakes up in the middle of the night when the sun moves behind a mountain range and creates a shadow for about five hours. “The sun just does a big circle around us, but the shadow makes it a lot colder, which keeps the drill from freezing into the glacier,” Neff explained. Then Roop added, “When the sun goes behind the mountain, the glacier crackles and pops—loud pops like gunshots—because of the temperature drop.”

Once they collect the ice cores, some are put into a pressure chamber under vacuum to remove all the modern air and are then melted. The gas from the ancient bubbles is released as the ice cores melt, and then gets carefully pulled into sample canisters, which are about the size of a SCUBA tank.

Near the end of this field campaign, the team will pull everything out to waiting helicopters using a big pink sled towed behind their Ski-Doo. The team will fly the ancient gases extracted from the ice cores to McMurdo Station before heading back to the University of Rochester Petrenko Lab, the Scripps Institute of Oceanography Severinghaus Laboratory, and the Oregon State University Ice Core and Quarternary Geochemistry Lab. The Ski-Doo will eventually hitch a ride from the helicopter as well, in a sling load dangling from a big wire cable tethered to the bottom of the helicopter. “Antarctica is a really emotional place," Roop said. "It’s a rare, rare, rare, rare opportunity to go where people don’t live, where people can’t live. This is the edge of where humans should be. There’s no trash, no animal tracks, no power lines, not even a bird; nothing to give you scale. It’s like the exhilaration of breaking a rule, poking a boundary. And there’s something thrilling about that.”

The National Science Foundation has a Presidential mandate to manage the U.S. Antarctic Program, under which it supports researchers, coordinates all U.S. science on the southernmost continent and in the surrounding ocean, and provides the infrastructure and logistical support needed to make the science possible.

Find out more about the University of Rochester Ice Core Expedition here. 

Thank you for reading.

Laura

Laura Faye Tenenbaum is a science communicator at NASA's Jet Propulsion Laboratory and teaches oceanography at Glendale Community College.

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