Yukimarimo. Photo: Shannon Coykendall

A late December bedecking of Yukimarimo around Summit Station seemed like “a present befitting the season,” wrote Ben Toth, whose team is keeping the NSF-funded research station and its ongoing experiments running through mid-winter.

“These little snowballs occur when fine frost layers form on the snow surface at cold air temperatures,” Ben explained. “These balls form due to weak wind conditions and become mobile, like little tumbleweeds across the surface, collecting in pockets sculpted by drift or in footprints.”

Ben says the team of five “finished off the year with a productive week sandwiched between the two holidays. Christmas Sunday was celebrated with the requisite Christmas tunes, a lit tree, decorations, and a Kiwi-style meal of “good tucker.” Rack of lamb and pavlova was on the menu as was roasted squash (the very last) and amazing maple syrup pies.

“New Year’s Eve was celebrated [with] a plethora of appetizers. . . . The tapas-themed meal segued into a comfortable evening counting down to 2012. All hands made it to midnight but retired shortly thereafter, rising somewhat later than usual on New Year’s Day to spectacular light and clear weather bringing in the new year.”

For more on Yukimarimo, visit http://homepage3.nifty.com/takaokameda/index.html)

Tumbled snow or Yukimarimo at Summit Station, Greenland. Photo: Shannon Coykendall

Comments (1) Jan 02 2012

 Frosty Freeze

The walk back from the atmospheric watch building seems a bit longer on cold winter days. From this point of view, Summit Station's science and operations building nudges the iconic Big House, with its roof-perched radome and welcoming porch light. Photo: Shannon Coykendall

We were glad to read that cold north winds, which for several weeks had been dominating the weather reports from Summit Station, subsided last week. A welcome relief to deep freeze conditions reported earlier. “We hit a wind chill of -107F earlier today and the ambient temperature is around -67F…it doesn’t take much wind to make it bite!”, wrote Shannon Coykendall on 30 November.

The moon rises over a winter storage berm at Summit Station. Photo: Shannon Coykendall

In addition to bringing the cold, north winds can blow exhaust from station generators into the pristine sampling zone. Ongoing atmospheric and snow chemistry measurements are impacted when the station’s emissions mix into the signal. So, during periods when the winds blow from the north, station personnel avoid activities that create exhaust.

Twice during late November and early December, the staff had to fire heavy equipment to collect snow to resupply the station’s water supply during north wind conditions. Each time, the science technicians followed protocol and notified the research community.

Heavy equipment stored outside at Summit Station in Greenland gets a nice layer of frost. Photo: Shannon Coykendall

Finally, last week, “Summit crawled out from underneath the north winds that have dominated the past few weeks. Bringing clouds and warmer weather, the southerlies created an opportune chance to catch up on making water and for the science techs to perform their non-north wind tasking,” wrote station manager Ben Toth. “The winds also gained strength this week, reaching sustained speeds of 15.5 knots. Temperatures this week ranged from a low of -60 C on Tuesday to a high of a balmy -34 C on Saturday.”–Kip Rithner

Comments (4) Dec 15 2011

Dangerous ice conditions in Davis Slough off the Tanana River in early December. Ice conditions like this make traveling along rural Alaska’s icy lakes and rivers hazardous. Photos courtesy Knut Kielland

Each winter as the temperatures in Alaska dip well below zero, the frozen rivers and lakes become highways and byways for many rural Alaskans. Just a short distance outside Fairbanks, one of Alaska’s largest cities, the lack of traditional roads and bridges reminds one just how rural and rugged a large part of Alaska is. With few traditional roads, many rural Alaskans navigate the seemingly frozen bodies of water on snowmobiles and dog sleds.  And all too often they come in contact with dangerous ice.

This is something ecologists Knut Kielland and his colleague Bill Schneider, an oral historian, know all too well. Kielland and Schneider, both avid dog mushers and researchers at University of Alaska, Fairbanks (UAF), have been criss-crossing the Alaska countryside along the Tanana River outside of Fairbanks for nearly 25 years. During that time the two have certainly run into their fair share of dangerous ice, but there were several unusual phenomena associated with dangerous ice that piqued their interest.

Knut Kielland came up with the idea to study the phenomena behind dangerous ice while dog mushing. Here he is guiding his team through overflow on the Anaktuvuk River on Alaska’s North Slope.

Degrading Ice

At 584-miles long, the Tanana River is a natural force that cuts through the landscape of central Alaska. During the winter the Tanana River exhibits a wide variety of dangerous ice conditions, ranging from overflow (water on top of the ice surface covered by dry snow) to shell ice (ice with air pockets underneath). “The most insidious ice condition is degrading ice,” Kielland said. “This condition refers to ice that forms normally during freeze-up and represents a safe travel surface in early winter. However, as the name implies, degrading ice exhibits dangerous thinning during mid-winter even at very cold (-30°C) air temperatures. The physical mechanisms behind this phenomenon and the distribution of such ice conditions are a major focus of our project.”

With support from the National Science Foundation, Kielland, Schneider and a multidisciplinary team of researchers set out to study and map the physical conditions behind winter dangerous ice conditions, as well as document local knowledge and observations across a 200-mile study area near the Tanana River. The data from the project will help scientists understand the forces behind dangerous ice, and give rural Alaskans tools that may improve public safety.

A Complex Issue Needs a Complex Approach

Kielland wanted to study dangerous ice from multiple angles, including human interactions with this natural force. To do that, Kielland paired teams of natural scientists with oral historians and ethnographers to take a holistic approach.

“In terms of the multidisciplinary approach, we’re talking about climatology, hydrology and the physics of snow and ice—that’s the natural science part. In terms of the social science, it’s both the science of going about how to collect oral histories and learning about how residents view and experience their environment, and more directly in terms of how they experience the changing winter conditions, particularly in regard to snow and ice conditions,” Kielland explained.

Sam Demientieff of Fairbanks inspects ice degradation in Moe Slough, February, 2010.

Community Involvement

Involving local communities in the study area has been a key part of the dangerous ice project.  Many of the villagers and townspeople have traveled the frozen rivers and lakes for decades and have valuable knowledge and insight that machines and computers simply can’t duplicate.

To gather data on how locals call upon years of experience and training to frame their descriptions and evaluate ice conditions, Kielland looked to his longtime friend and oral historian Bill Schneider to record interviews with locals. Having lived and worked in Alaska for decades, it was relatively easy to tap the wealth of knowledge about rural Alaska’s frozen highways.

Residents of Manley Hot Springs meet to discuss the ice conditions along the river trail between Manley and the village of Tanana. LPictured from left oto right: are, John Dart, Espen Jervsjö, and Frank Gurtler (Manley), and Charlie Wright (Tanana).

“Because we’ve lived here for a while, we have friends and acquaintances—and acquaintances of acquaintances—in a variety of communities. We were very fortunate that we could pretty much come into a community and establish a rapport with them,” Kielland said.

Ice Interviews

The team worked with communities in Fairbanks, Manley and the village of Tanana to gather their observations on the distribution and abundance of dangerous ice phenomena and how they impact  subsistence activities and travel throughout the winter. With help from Karen Brewster, a research associate for the Oral History Program at UAF, the team has hosted several workshops and interviews in the field with river travelers, the results of which are now being posted online.

Research associate Karen Brewster films interviews with Sam Demientieff (left) and Wally Carlo (right) on the Tanana River, March 2011.

“We  do semi-direct interview [s], take a lot of photographs and videotap[e]ing of areas and interviews,” Kielland said.  Interviews and photos from the dangerous ice project are made publicly available through the University of Alaska Fairbanks’ Project Jukebox.

The combination of physical data and recorded oral histories has started to crack some of the mysteries of dangerous ice, shedding new light on the phenomena and how rural Alaskans deal with it.

Cracking the Ice

Some of the initial findings are a bit of a surprise to Kielland and his colleagues. Initially, he hypothesized that dangerous ice occurrences were tied to shallower (< 1 m) portions of the river more susceptible to melting from below due to ground water upwelling. However, that’s not always the case. The team has observed cases of dangerous ice in deeper waters (> 3 m).

Kielland has also documented very localized instances of dangerous ice where, “it’s almost like somebody sat down at the bottom [of the river or lake] with a laser and shot a hole in the ice. Hydrologists on the project are still working to understand the physics behind such localized events.

“We’re learning about the phenomena, about how wide- spread it is, and we’re learning about how people deal with it—though mostly they just want to stay far away from it,” Kielland said. “We don’t know much about how it has changed through time yet, but we hope our conversations with local residents can shed further light on that.”

Although winters in Alaska are getting warmer on the whole, dangerous ice phenomena aren’t necessarily a direct consequence of climate change.

“Winters in Alaska are getting warmer and climate predictions call for more snow. Both of those factors will probably exacerbate the situation, if anything, but we don’t consider this a direct consequence of warming. As I mentioned, we see the phenomenon even when it’s very cold out,” he said.

Lessons Learned

With the second year of the dangerous ice project now coming to a close, Kielland and Schneider hope to extend it for one more year to continue unraveling the mysteries behind dangerous ice.

The lessons learned from this project will not only tell us where dangerous ice is located and it’s potential causes, they will also help rural Alaskans avoid a wintertime problem that claims lives every year.

“We hope that at the end of the day, there will be an improved understanding from both our and their [rural Alaskans’] point of view about the nature of the phenomenon and how it’s distributed along the length of the Tanana that many of them travel,” Kielland said. For more information about the Dangerous Ice project (still under construction), visit: http://jukebox.uaf.edu/dangerice/start.htm. –Alicia Clarke

Comments (1) Dec 05 2011

In an image taken with a 360-degree-view fisheye lens, Ed Stockard stands observing a full-sky show, a circular halo called a parhelic circle along with 22 degree and 46 degree halos. Also present: a circumzenithal arc, an upper tangent arc, and a faint Parry arc. Visit http://www.atoptics.co.uk/halosim.htm and view the frequent and infrequent links on the left. Can you find them all? Photo: Ed Stockard

Marko Riikonen visited South Pole in 1998-1999 to film and study the optical effects of ice crystals in the atmosphere, which manifest visibly as halos across the sky. He was part of a team on an NSF grant led by Walter Tape, a mathematics professor from the University of Alaska, Fairbanks. On January 11th, 1999, the team hit the optical jackpot. An exceptionally bright halo display, which included several frequent and rare halos, appeared in the sky. Marko recalled that it lasted almost an hour—an unusually long time for such a magnificent display—and a good number of station folks came out to watch it. He termed the display an “exhausting experience.”

Riikonen had had his share of discovery prior to his trip to the South Pole; in Chile he witnessed the so-called Lascar display which had at least five new halos, and is still unexplained. Says Marko, “We tried to explain it with cubic ice, but that’s not the answer.”

Meanwhile, in 1999, a few months after Riikonen left South Pole, I found myself heading to Summit Station, Greenland, for the first time. In mid-March four of us went to open the research site after a winter hiatus.  Although I had seen some polar halos in Antarctica, I was totally unprepared for what I saw one day while grooming the skiway.

From Oct 15th 2001: Skiway flags salute a nice 22 deg halo with a sunvex parry on top. The wider “v” below is the upper tangent arc. Completing the photo is the partial parhelic circle and associated parhelion or sun dogs. A very faint helic arc is visible to the right. Photo: Ed Stockard

Looking out from the Tucker I saw two halos around the sun and a variety of arcs that I had not a clue about. I stopped the machine and got out. Looking around I could see what I know now is called a parhelic circle encompassing the sky. Literally, turning around in 360 degrees I could see this halo. I started talking to myself. I said words I can’t repeat in this article!

I climbed back in the Tucker but could only drive a short distance before I had to stop, get out and repeat to myself the words of absolute amazement. I didn’t know at the time how the arcs and halos formed. I don’t remember all of the individual sights I saw but that day stuck in my mind.

Fast forward, this time 12 years, to 2011 and I am now spending August to November for the second consecutive year here at Summit. I have spent quite a few years working for PFS/CPS in Kangerlussuaq, which is the logistics hub for the U.S. National Science Foundation’s research program in Greenland. I’ve been a frequent contributor to this blog from my photographic work there. Kanger, as we call it, has remarkable auroras but I’ve rarely seen halos in Kanger like those on top of the ice sheet at Summit.

A typical but beautiful 22 deg halo marks the first phase of 2011-2012 winter operations at Summit Station. Photo: Ed Stockard

A 22 deg halo with faint parahelion or sun dogs. Marko suggested I use a sun blocker, which I made from the lid of a 5-gallon bucket on a 12-ft piece of old bamboo. The blocker keeps the photos from washing out and being over-exposed. Photo: Ed Stockard

Marko Riikonen found my photos in 2010, after they showed up on Atoptics.co.uk and on my flickr.com site. He picked one to include in his new book on halos. He has mentored me in optical photography through this current phase here at Summit, often emailing with obvious enthusiasm. It has been a delight and inspiration having his insight and tips on photographs, as well as his explanations of the phenomena I’m witnessing and documenting.

Halos and arcs can be seen worldwide, but the varied and rare phenomena mostly occur at the higher latitudes.  In some remote places in the Arctic and Antarctic, scientists have to rely on the eyes (and cameras) of others. My work here at Summit Station during the early arctic winter has allowed me a unique vantage point to photograph atmospheric optics in detail, for enthusiasts and scientists such as Riikonen to gather more knowledge about them.

Halos can occur by moonlight too. Here, a fairly complex 2010 lunar halo display. Present and easily visible are the 22 deg halo, parahelic circle, parahelion or moon dogs in this case, the upper tangent arc and parry arc along with a lower tangent arc on the horizon. Photo: Ed Stockard

As this correspondence has developed Riikonens’ comments have introduced me to a new vocabulary: Wegener, Schulthess and Kern arcs; Tape infralateral arcs; and all kinds of halos. Riikonen says, “When the temps fall below -30 C, you probably will get some odd radius displays, like last year.” He also says my photos have advanced the field a bit: “The Greenland ice cap halo skies have been a question mark until your photos started coming along. You have already written you name in the halo history.”

Cool.

Riikonen himself is well embedded in halo history, living in Finland in an area that often sees halos. On the night of December 7 /8 2008 in Rovaniemi, Finland, five new halos were revealed. “It was a great night. The display was created with [a] spotlight in diamond dust. The diamond dust was so thick that the moon did not shine through, so the only possibility to see halos was to use the spotlight. The cystals were huge. You could look at them with [the] naked eye. I had never seen a high-quality diamond dust like that.”

Riikonen’s travels in search of halos have taken him to Resolute Bay in Canada and “the pole of cold” in Oymyakon, Siberia.  At Oymyakon, in 1997, the optics were found to be rather typical. In his words, “We went to look for halos in the extremely low temps. Well, they were nothing special. When it gets too cold, it is mostly just 22 halo.”

I asked Marko about climate change and the effects it may have on these optical elights. He answered, “The high cloud halos in Finland have gotten markedly poorer soon after we entered new millenium. We used to have a so-called ‘halo spring’ in April-May during which numerous good, high-cloud displays were observed, but now there has been no halo spring for almost a decade. The Finns have been observing halos since the beginning of [the] 1980′s, so it is three decades of data now. That is of course way too small of a sample to say that climate change is responsible for the better quality high-cloud displays famine. Maybe the first two decades were exceptionally high-quality and now we are back to normal. Or maybe that was the norm and due to the climate change high-cloud halos have become poor.”

The above links and the halos mentioned are only a partial list of what Riikonen has seen. Marko hopes others will also photograph the world’s wonderful sky and provide shots of little-seen and possibly never-photographed optics. To all in the Arctic, Antarctic and around the globe:  Keep the camera ready. . . Jot down a few facts with the photos—temperature, clouds and winds may help.  Share in Marko’s enthusiasm and put forth some good data with remarkable photos. You might even hit that optical jackpot.—Ed Stockard

Comments (0) Sep 29 2011

2011 PolarTREC teacher, Susy Ellison, samples spruce trees for a dendrochronology study in Alaska's Arctic National Wildlife Refuge. All photos: Susy Ellison

Susy Ellison is the high school science teacher we all wish we’d had. With projects like designing and building an energy-efficient straw-bale classroom, installing solar panels on the school’s roof, and building a greenhouse (and growing things in it), Ellison is infusing her students with a strong sense of what she calls environmental literacy. Now in her 15^th year at Yampah Mountain High School in Glenwood Springs, Colorado, Ellison spent the summer with two teams of Alaskan researchers as a PolarTREC teacher, so this year’s class will, no doubt, be in for some fun and interesting science activities.

Ellison’s love for Alaska goes back to graduate school when she spent time in Prudhoe Bay studying how arctic foxes interact with nesting shorebirds and small mammals. Her field experience served her well this year as she traveled to the Arctic National Wildlife Refuge for a six-day NSF-funded tree-ring study with Kevin Anchukaitis and Angie Allen (Lamont-Doherty Earth Observatory),  and to the Raven Bluff Site for two weeks with Jeff Rasic (UAF/NPS), William Hedman (BLM), and Ian Buvit (Central Washington University) for a NSF-supported study on early human settlement in arctic Alaska.

For the tree-ring study, field team members spent their time extracting straw-sized cores from standing white spruce trees in five sites spread over a few miles; Anchukaitis will compare annual growth rings from these cores with samples taken from fallen trees. By analyzing the thickness of annual rings, they will reconstruct North Slope climate and ultimately determine controls on the extent of arctic forest growth.

Traveling light - Ellison and Allen congratulate themselves on hauling all their gear in one trip.

“The tree-ring study was really interesting. Many scientists think that with climate warming and more carbon dioxide in the atmosphere, trees might just grow and grow and grow, but new research says this may not be true. You can keep feeding someone, but it’s not going to make them taller,” explains Ellison. “I was impressed with how pretty simple science can provide pretty big answers. There were only three of us and we were just out there. We travelled light and fast. It was fun!”

Following a 10-day break exploring the Kenai Peninsula, Ellison joined Jeff Rasic’s team for a rainy and cool two week archaeological excavation near Kivalina.  Despite the soggy weather, the group made the best of things and worked hard to maximize their field time. In addition to searching for artifacts in one-meter square pits started during the 2010 field season, Ellison participated in a soil survey and in reconnaissance flights wherein the group looked for new archaeological sites.

“We usually hear that the first people to North America came from Asia via the Bering Land Bridge and then headed south. The Raven site is about the same age, about 12,000 years old, as the Clovis culture sites farther south. At Raven we looked, in particular, for these fluted spear points so that they can be dated and compared to similar Clovis-age points. The idea is that people may have moved back and forth between Alaska and southern North America rather than unidirectionally,” says Ellison.

“The similarity in these projects is that we were looking at old stuff, attempting to get information that can be applied to the present and, perhaps, predict future changes in the Arctic,” Ellison says. “The scientists were so passionate about their studies and the field season in Alaska is so short – they had to get it done. Everyone worked really hard to complete the work required in the short time period.”

Ellison tries to stay dry while recording soil profile data.

Now that a new school year is underway, Ellison is thinking about ways to share her PolarTREC experiences with Yampah. So far, she’s considering having students look at tree rings to determine Colorado’s long-term fire history. She would also like to take a group backpacking in Utah to see some archaeological sites close to home while considering what clues they might leave behind for future archaeologists to find.

Ellison’s school is run by the Mountain Board of Cooperative Educational Services, and serves students from four public school districts.  The school serves as an alternative to students who have been unsuccessful in other area high schools for one reason or another.

“Teaching science at Yampah is very challenging,” Ellison says. “Our classes are ungraded, which means that in one class I have students from all grades with all levels of science proficiency. I teach life, physical, and earth science so I have a lot of information to distill. Then, I put my own spin on it. I like to have an environmental focus with very hands-on projects. My experiences with PolarTREC have given me so many new ideas for how to communicate climate change issues and science research  to all my students, regardless of their science background.”—Marcy Davis

PolarTREC (Polar Teachers and Researchers Exploring and Collaborating) is funded by the National Science Foundation’s Office of Polar Programs and managed by the Arctic Research Consortium of the United States, or ARCUS. The program aims to give teachers professional development experiences conducting research in the polar regions with career scientists to boost the teachers’ content knowledge and to give them hands-on experience in scientific inquiry. ARCUS is accepting applications through the end of September from teachers and researchers interested in participating in the PolarTREC program during the 2012-2013 research season. Visit the ARCUS PolarTREC website for more information: http://www.polartrec.com/

Comments (0) Sep 23 2011

PolarTREC teacher spent his summer “under this mass of moving ice”

PolarTREC teacher Michael Lampert at the Engabreen Glacier. All photos: Michael Lampert

Buried two hundred meters below Engabreen Glacier, one of a handful of outlet glaciers that drain northern Norway’s Svartisen ice cap, is the Svartisen Subglacial Laboratory, one of the world’s most unique settings for glaciological research.  Just north of the Arctic Circle, the facility came online in conjunction with a new hydro-electric power plant in 1993. An elaborate network of more than 100 km of subglacial tunnels funnels glacial meltwater through the mountain to turbines at the Glumsfjord Kraftverk power station near the glacier base—and allows researchers direct access to the underside of the glacier.

Living quarters and a science lab are housed within barracks-like structures in a tunnel below the surface near the glacier’s origin. The only light is the eerie yellow glow emitted from sodium vapor lamps and headlamps affixed to scientists’ hardhats.

The Svartisen Subglacial Laboratory houses underground labs and living space.

Michael Lampert, a 2011 PolarTREC teacher* from West Salem High School in Salem, Oregon, who joined PI Neal Iverson (Iowa State University) and team on this year’s field expedition, describes his first impression of the lab:

“A helicopter took us up to the top of [the] glacier where we were to enter the tunnel to the Laboratory. I kept looking for a grand entrance, but when we arrived it was just a post with a doorway. We shoveled out a bunch of snow so we could get the door open then walked about 100m through a corrugated pipe that opened into a large room,” Lampert explains.  “It was a little like being in a sewer – dark, drippy, cold, humid air that is very still. You can always hear water rushing through the tunnels. It’s a very odd feeling. There was this unbelievably strange emptiness. I wasn’t expecting it.”

Svartisen's foyer...

Lampert joined Iverson on the latter’s NSF-funded project to understand how, and how fast, Engebreen Glacier moves. During underground stays of up to three weeks at the subglacial lab, the group works at the glacier-bedrock interface, measuring water pressure and microseismicity, tiny earthquakes associated with glacier movement. Data obtained at Svartisen provide fundamental information about variability in glacier movement, information Iverson hopes will translate to long-term predictions about the ice sheets covering Greenland and Antarctica, and their potential contributions to sea-level change.

Lampert mucks out the tunnel.

“The idea here, the overall goal, is to stimulate a rapid glacier movement event by pumping water under the glacier for an hour while measuring the resulting microseismicity,” explains Iverson. “We measure water pressure in pump tests and embed accelerometers in the glacier to monitor ice acceleration. We then correlate these motion data to seismicity measured in the tunnel and on the glacier surface. We manipulate the system to try to understand it better. We are trying to calibrate motion in a very large-scale laboratory so we can apply results to other glaciers.”

Melting last year's ice.

Donning rubber boots and suits to protect them from mud and water, researchers worked to free instruments left in the glacier ice last summer for maintenance and repairs. To get at the equipment, the team first had to melt free a steel door separating the tunnel from the glacier. Using relatively hot water (sixty degrees) from a fire hose directed at the door for an hour, Lampert , who has a background in physics, got his first up-close glimpse of the Engabreen’s underbelly. In a May 2 PolarTREC journal entry he wrote:

“The very bottom of the glacier is a mix of sediment and debris but there is a sudden line of clear glacier ice, often you see lines like this on icebergs that have calved into the ocean. The blue ice has a magical appearance when illuminated with a flood light.”

The glacier's base is mixture of ice and sediment.

Next, the team melted horizontal and vertical shafts through the ice to expose boreholes in the rock through which instrumentation, cables, and wiring pass from instruments embedded in the glacier to lab computers. During the year, the holes become clogged with ice that must be removed periodically. It’s a constant fight against moving ice, which can close off passageways at rates of 1-2 meters a day.

“Ice [that is] under 200 meters of pressure oozes like toothpaste. [It’s] not brittle like the ice in your freezer,” explains Lampert. “Once the sensors are in the glacier and we stop melting, the ice moves back in. The glacier is moving so the ice will ooze around you in the course of a day. You can see a difference within an hour. It’s kind of creepy. Sometimes I would sit in a space in the ice and close my eyes. I would think about just exactly where I was – under this mass of moving ice and that really put me in touch with Earth’s geology. That was one of the coolest things ever!”

Enjoying the view from outside the lab entrance.

Instrumentation includes a friction plate, a granite-topped metal disc about a foot in diameter and loaded with sensors that measure the force of the glacier as it slides over bedrock. The plate, the only one of its kind, also contains a water pressure sensor and an acoustic sensor that ‘listens’ to the glacier’s sounds as it moves past. Other sensors include accelerometers in palm-sized capsules that monitor ice motion.

“Some accelerometers have cable tethers that are fed through boreholes in the underlying rock to lab computers.  Some transmit wirelessly through the tunnel. Both types have advantages and disadvantages. There is lots of screwing around with electrical stuff in conditions a degree above freezing and 100% humidity,” Iverson says.

Accelerometer maintenance is serious business.

Once instrumentation is tested and reinstalled, the shafts are left alone so that the ice “heals.” Then water is pumped through the tunnel at the base of the glacier and the team waits for data.

“We know for certain that moving ice produces seismicity and the character of our data seem to indicate motion of ice as opposed water, “ explains Iverson. “We are still working out what our data mean. The signals look like we are recording the basal motion of the glacier as it slides over rock, but we are working through the details as the data can be very noisy.”

Other sampling efforts include ice coring, sediment and geologic analyses.

Miriam Jackson takes an ice sample.

As for Lampert, he’ll bring lots of stories back to his community and classroom this fall.

“The whole thing was out of the world – so totally surrealistic! These scientists are getting at the real fundamentals of science. I want my students to really understand that applying science in the field is the best part. Then there’s the living in a tunnel – there’s a psychological effect with it that I didn’t expect. When we finally walked out from this place of 24 hours of darkness into the 24-hour day of the polar summer, it was wild…quite a metaphor to walk out of total darkness into light, from nothingness to life.”—Marcy Davis

PolarTREC (Polar Teachers and Researchers Exploring and Collaborating) is funded by the National Science Foundation’s Office of Polar Programs and managed by the Arctic Research Consortium of the United States, or ARCUS. The program aims to give teachers professional development experiences conducting research in the polar regions with career scientists to boost the teachers’ content knowledge and to give them hands-on experience in scientific inquiry. ARCUS is accepting applications through the end of September from teachers and researchers interested in participating in the PolarTREC program during the 2012-2013 research season. Visit the ARCUS PolarTREC website for more information: http://www.polartrec.com/

Comments (1) Sep 16 2011

Summit Station Images Featured on Atmospheric Optics

Greenland Glory. Photo: Ed Stockard

The above photo, and the one just below, have been featured recently as the Optics Photo of the Day on the Atmospheric Optics website (http://www.atoptics.co.uk/). Ed Stockard shot both images at Summit Station on Greenland’s ice sheet, where he is working this fall.

The Atmospheric Optics website is devoted to explaining and exploring the visual results of light playing on particles in the air–ash, dust, and in Ed’s case, ice. The rainbow-colored rings encircling the building form a “glory,” explains website curator Les Crowley, the result of “sunlight diffracted almost directly back along its path by very small fog droplets.” Click the picture for a better view. Glory indeed.

Visit the Atmospheric Optics website to learn more about optical effects in the atmosphere, and to find out when, how, and where you might be able to see some in person.

A short description of the science behind the optical effect accompanies each image. You may also visit Ed Stockard’s flickr page, which he is updating with more lovely images from Summit (http://www.flickr.com/photos/coastaleddy/ ).–Kip Rithner

Greenland Halos. Photo: Ed Stockard

Comments (0) Sep 12 2011

Katey Walter Anthony (UAF) smiles after a good day of field work. Photo: Valera Fedoseev

In terms of carbon footprint, though one hears a lot about carbon dioxide, it’s methane that wears the size 12 clodhopper. Methane is more effective at trapping heat in earth’s atmosphere than carbon dioxide and also contributes to the degradation of the ozone layer. When permafrost thaws, release of methane into the atmosphere from anaerobic decomposition contributes to climate warming, which subsequently causes more permafrost thaw – thus acting as an important feedback loop in global climate. Katey Walter Anthony (University of Alaska, Fairbanks) and an international team of colleagues are studying permafrost and thermokarst lakes to better understand how thawing permafrost and the subsequent release of methane is contributing to climate warming. Since 2008 Anthony and colleagues have worked on the interdisciplinary study in Cherskii and Yakutsk, Russia, all over Alaska, in western Canada, Greenland and Sweden describing the distribution of permafrost and the process of landscape evolution and gas escape as permafrost thaws.

“We have a pan-Arctic focus with the goal of understanding carbon release from permafrost. Not only are we describing the extent of thermokarst in Siberia, Alaska, western Canada and other regions of the Arctic, we’re looking at how thermokarst lakes develop and release methane in particular,” says Anthony.

Permafrost, soil at or below the freezing point of water for at least two years, is common at high latitudes. As the climate warms, however, permafrost thaws and forms an irregular landscape called thermokarst (the pitted nature of the surface resembles those developed in karst areas of limestone). In surface depressions, lakes form where massive ground ice melted. Permafrost contains vast reserves of carbon stored within a frozen framework that is released when permafrost thaws.

Anthony and colleagues are interested in yedoma, a specific type of permafrost that is particularly high in carbon and supersaturated with ice, about 50-90% by volume. Formed in unglaciated continental areas during the last ice age, yedoma is most prevalent in northeastern Siberia where it may be tens of meters thick. Thawing yedoma yields a significant source of atmospheric methane.

“Thermokarst lakes formed from the thawing of yedoma are very efficient at releasing carbon, in the form of methane, into the atmosphere,” Anthony explains. “As the ice melts, water and 46,000 year-old methane, CH₄, are released. We are trying to quantify how much carbon is released as well as the variability in different regions.”

When headed to the field, Anthony and her co-investigator, Guido Grosse, first identify likely areas of permafrost exposures using satellite imagery. Ideal locations are usually along rivers where cut banks have excavated steep exposures that may be up to 50 m tall.

Researchers survey permafrost-laden soils at the Arctic Coast north of Cherskii, Northeast Siberia. Soils rich in ground ice also have high organic matter content. When this permafrost thaws, formerly frozen carbon becomes available which produce carbon dioxide and methane. Photo: G. Grosse

“These are the best places to work because we can see 60,000 years of history all at once. You can see the whole layered cake of ice and frozen soil in cross section! We can tease out a lot of information about past permafrost and climate,” Anthony says. “We have to be very careful when we sample to find a fresh cut that has not thawed in the recent past. The first part is just moving dirt with shovels and scrapers so we have to be very careful. We have to work quickly because the permafrost can thaw very quickly. We sample and describe different units with a focus on the amount of ice and carbon in representative layers. We can scale up. Studying broad exposures has some big advantages over permafrost coring, where our interpretation of an area is otherwise limited to what we find in 4cm diameter cores.”

Anthony does much of her methane field work during winter. And, while she says it’s no fun to wake up in -30 degree temperatures at field camps, winter work is easier in some ways. Lake ice provides an opportunity to map methane bubbles on thermokarst lakes. Coring permafrost requires the use of a permafrost drill, a gas-powered auger with a core barrel and drill bit at the end. Anthony says permafrost coring is often most easily accomplished in winter conditions when the permafrost is frozen solid. Samples can be quickly acquired from a snowmobile and there’s less chance of the core casing freezing up during the coring since it’s already cold.

Anthony and then graduate adviser, Terry Chapin (UAF), engage in a tug of war to separate a tube containing lake sediments from the core head. Photo: M. Chapin

Anthony’s team also prefers coring thermokarst lake sediments in the winter because they can use lake ice as a stable platform for field work. Sediments from the bottom of a lake can tell Anthony how old the lake is–some lakes developed at the end of the last ice age nearly 12,000 years ago, while others developed much later and have been expanding since.

Sometimes lake coring in summer is necessary. “Summer lake coring requires a huge amount of work. It’s very dirty. There are lots of mosquitoes. I have spent hours hammering a core barrel into the lake bed from a raft just to have nothing come up. It’s much easier in the winter when we can do it from the ice covering the lake. Then it requires much less gear and it’s stable,” says Anthony.

Methane bubbles rising from the lake bottom are trapped by winter ice. Photo: K. Walter Anthony

Anthony also maps lake methane bubbles during winter. Methane formed by microbes from thawing permafrost is released from lake bottoms in the form of bubbles all year long. In summer, bubbles rise to the top of the lake and burst, releasing almost pure methane into the atmosphere, but in the winter, lake ice forms a lid that traps methane bubbles.

“We use shovels to remove any fresh snow from the lake ice surface. What we find is really neat–the ice looks black and had beautiful white bubbles stacked on top of each other in place to place–much like the stars scattered across the night sky,” Anthony explains. “We map the distribution of the bubbles which get trapped, forming tall columns of methane. We can tell where the gas is coming from, how it clusters. We get a good spatial data set.”

Anthony and Dragos Vas (UAF) check the volume of gas collected in under-ice bubble traps on a thermokarst lake in Fairbanks. Photo: M. Grimes

Back in the lab Anthony sub-samples permafrost and lake cores for radiocarbon dates, a method that helps her and colleagues understand the history of permafrost formation across northern Siberia and Alaska.

In 2011, Anthony’s team, along with students and post doctoral candidates from the University of Alaska, Fairbanks, returned to Seward Peninsula and interior Alaska field sites to recover time-lapse cameras, temperature data loggers, and bubble traps, which record the rate of gas release. The team also worked in Cherskii, Russia. During that expedition, Anthony worked with three students and a postdoc who have sub-projects studying permafrost and peat along the Kolyma River.—Marcy Davis

Katey Walter Anthony’s research is funded, in part, by NSF, NASA, and the Department of Energy

Comments (0) Sep 08 2011

Impacts could have profound implications on atmospheric carbon and climate

The Anaktuvuk River Fire is the dark shape in the right-center of this NASA-MODIS image of the North Slope of Alaska, acquired June 14, 2008. The burned area is bordered by the Nanushuk River on the west and the Itkillik River on the east. Credit: Courtesy of Jim Laundre, MBL

In a study published in Nature, Marine Biological Laboratory (MBL) senior scientist Gauis Shaver and his colleagues, including lead author Michelle Mack of the University of Florida, describe the dramatic impacts of a massive Arctic wildfire on carbon releases to the atmosphere. The 2007 blaze on the North Slope of the Alaska’s Brooks Mountain Range released 20 times more carbon to the atmosphere than what is annually lost from undisturbed tundra.

As wildfires increase in frequency and size along Alaska’s North Slope, the team contends the disturbances may release large amounts of the greenhouse gas CO₂ to the atmosphere and accelerate the transformation of the frozen, treeless tundra of today into a different kind of ecosystem less capable of storing carbon. Together, the impacts could have profound implications on atmospheric carbon and climate.

Arctic tundra landscapes store huge amounts of carbon in cool, wet soils that are insulated by a layer of permanently frozen ground, or permafrost. Fire has been almost nonexistent in Alaska’s North Slope for thousands of years and the effect of fires on the carbon balance of tundra ecosystems is largely unknown. However, with warming temperatures over the past half-century, the climate in the region is in transition, spurring more thunderstorms, lightning, and wildfires.

In 2007 the Anaktuvuk River fire ravaged a 40-by-10 mile swath of tundra about 24 miles north of Toolik Field Station, where Shaver is the principal investigator of the NSF’s Arctic Long-Term Ecological Research project. The blaze was the largest ever recorded in the region.

While the Anaktuvuk River fire scorched only upper soil layers that are about 50 years old, it caused the release of more than two million metric tons of CO₂ to the atmosphere. This amount is similar in magnitude to the annual carbon sink for the entire Arctic tundra biome averaged over the last quarter of the twentieth century. According to Shaver and his colleagues, an Arctic regularly disturbed by fire could mean massive releases of CO₂ into the atmosphere, a decrease in carbon stocks on land, and a rapid impact on climate.

Shaver has been studying the Arctic tundra since the mid-1970s, and he knows how to look for gradual shifts in a landscape that is changing, but very slowly. Large disturbances such as fire—which leave the land open to rapid re-growth—have been rare. As the tundra rebounds from the Anaktuvuk River fire, Shaver and his colleagues are watching closely to see if the fire will nudge a major transformation of the North Slope groundcover that is already slowly underway.

MBL Ecosystems Center scientist Chris Neill inspects burned tussocks at the Anaktuvuk River fire site, July 2008. Credit: Jason Orfanon, MBL Logan Science Journalism Program

More shrubs are expected to appear in the Arctic landscape as the climate warms, a trend that may be accelerated by the advent of fires. “Satellites tell us there has clearly been a greening of the Arctic over the past 30 years,” Shaver says. Many observations point to a warmer landscape that will be dominated by shrubs, rather than the grasses and mosses of today. Some scientists forecast that large parts of the Arctic tundra will eventually become forest. “A key question is whether the conditions on these burn sites are more favorable for the establishment of new seeds, new species,” Shaver says.

Moreover, the burn, because it is darker, absorbs more solar radiation than undisturbed land. “You have much higher rates of permafrost thawing, and depth of thaw, on the burn,” Shaver says. All of these immediate consequences of the Anaktuvuk River fire reinforce the effects of a warming climate on the Arctic tundra. And the scientists don’t yet know if the land can recover the carbon and energy balance of its pre-burn state, or if they are looking at a “new normal,” Shaver says.

This research was supported by the NSF Division of Environmental Biology, the Division of Biological Infrastructure, and Office of Polar Programs, the National Center for Ecological Analysis and Synthesis, and the Bureau of Land Management Alaska Fire Service and Arctic Field Office.

Source: Marine Biological Laboratory

Comments (0) Aug 06 2011

Perhaps the bear thought this Iridium antenna, part of an autonomous monitoring site in Greenland, was an ice cream cone. Photo: Bo Madsen

Technicians visiting autonomous instruments on Greenland’s northwest coast last week found more evidence that polar bears have a taste for science.  An American and a Danish scientist conducting maintenance on GNET stations south of the Thule Air Base found one had been “aggressively damaged” by a bear, wrote Finn Bo Madsen of Technical University of Denmark (DTU).  The Danish institute is collaborating with U.S. National Science Foundation-funded researchers led by Mike Bevis (The Ohio State University) to maintain a network of more than 45 Global Positioning System (GPS) and seismic monitoring stations that ring the perimeter of the world’s largest island.

GNET is part of the larger Polar Earth Observing Network, or POLENET, which has also instrumented Antarctica’s ice sheet with autonomous monitoring devices.  Scientists study the data collected by these instruments to monitor the mass balance of the world’s great ice sheets. Seismic information, combined with very precise GPS measurements, tell scientists about regional changes in melting or accumulation on the ice sheets, information that helps them to explain how the ice sheets are responding to changing climate.  The GNET system also records earthquake activity believed to be caused by post-glacial rebound—the land bouncing back under the lessening weight of Greenland’s shrinking ice cap.

This map of Greenland shows the sites where GNET installations are located. On the northwestern coast, technicians repaired polar bear damage at ASKY last week; to the north of ASKY and Thule Air Base, site KAGZ has been visited by bears twice. Image: GNET

Though GNET planners avoided areas known to be frequented by bears when they selected project sites, this is not the first time a polar bear has left its mark on a GNET monument. In 2009, a maintenance team visiting a site north of Thule Air Base found suspected polar bear damage on instruments and solar panels used to power the site during the summer. They repaired the damage, but the installation stopped sending data to scientists back in their labs shortly thereafter. A repeat inspection in 2010 revealed that bears “may have rubbed their backs on the monument, been chewing on cables or have given the equipment a thorough pounding with their paws,” reported Bo Madsen at the time.

This time, Madsen speculates that the bear was “perhaps scratching its back on the solar panels,” as a panel, antenna and cable were damaged. Technicians armed with repair kits spent more than five hours repairing the site, improvising additional ways to make the site less interesting to bears.  Madsen mentioned that the team would later assess how much data the site had collected in the interim.

Rare sight: this polar bear wandered down a path near Kangerlussuaq.

Meanwhile, a polar bear spotted on the edge of town was the talk of Kangerlussuaq, where CPS personnel staff the NSF’s logistics hub in Greenland. Polar bears are known along Greenland’s northern coasts, but are rare to the south, where Kangerlussuaq is located. Locals recalled that this was the first bear spotted near Kangerlussuaq since 1998; prior to that, the last bear was seen in 1957.—Kip Rithner

Comments (0) Jul 08 2011