To Inuit, Sea Ice Means “Freedom”

May 13, 2010

  

At the edge of the sea ice, a Barrow resident awaits the return of a seal-skin whaling boat. Photo: Faustine Mercer

Here’s a really interesting story on Shari Gearheard’s NSF-funded people and sea-ice study. Gearheard, a glaciologist from U Colorado’s National Snow and Ice Data Center, combined scientific sea-ice studies with the traditional knowledge of Inuit collaboraters who’ve spent their lives on or near the ice.  The aim: to gain a better understanding of how sea ice is changing in the Arctic–and how community lifeways around the Arctic may be changing in response.  

Gearheard and her collaborators speak extensively in the piece, and what they have to say about the changes they’ve seen in sea-ice conditions is compelling.   

“‘I’m a scientist so when I look at sea ice I see what its properties are. How dense it is. But I remember sitting with the hunters when we were all in Qaanaaq. They looked at the sea ice and the first thing they said they saw was ‘freedom’.  

‘(Sea ice) meant they could hunt for food. It meant they could travel to see relatives on the other side of the water, that they hadn’t seen all year.  

‘That was a very powerful thing for me as a person, not just as a scientist.'”–Shari Gearheard  

* * *

“‘When I was a boy, the ice used to hover around Barrow all year,’ 51-year-old Leavitt said. ‘Now when the ice takes off it doesn’t want to come back. So our hunting is very limited.'”–Joe Leavitt, Barrow resident and whaling captain  

* * *

“‘We used to live as nomads in those days,” Sanguya continued. “After Christmas, when there was enough snow, we’d go out on the sea ice and make igloos.  

‘In those days I didn’t have any math or measurements … or anything like that. But I remember looking down through seal breathing holes and the ice was so thick, they looked like they were tapering away.  

‘Today you don’t see that very much. You’ll probably see 4 feet or 5 feet (down) and that’s it.'”–Joelie Sanguya, Elder and hunter, Clyde River, Nunavut

Hunters in Qaanaaq, Greenland traditionally travel over the sea ice on dog-powered sledges like these. Photo: Hans Jensen


Travels with Kenji

April 28, 2010

Kenji Yoshikawa calls in adjustments to his permafrost outreach itinerary. Photo: Ned Rozell, http://www.alaskatracks.com

Permafrost troubadour Kenji Yoshikawa (University of Alaska) last week visited permafrost observatories in remote villages of Alaska. “In general weather was not great this spring especially Bristol Bay area,” Yoshikawa wrote to PFS’ Alaska support manager Marin Kuizenga. “I could not make some villages by the weather at this time.”

Kenji is a one-man Arctic Observing Network or AON, and he spends the summer in perpetual movement (or so it seems to us) servicing permafrost sites sprinkled all over the Arctic, and concentrated in Alaska. At each stop, he brings his permafrost knowledge to local residents.

Yoshikawa presents permafrost information to Alaska's next generation. Photo: http://www.uaf.edu/permafrost/

Ned Rozell joined Yoshikawa last week. Ned wrote about the adventure and posted pictures to his AlaskaTracks Web site. Don’t miss his observations.

Yoshikawa also maintains a permafrost outreach site at www.uaf.edu/permafrost/. This fun site is full of tidbits about the places he visits, amply peppered with pictures. Make sure you have time to enjoy this site when you visit, because it’s easy to linger in Kenji’s world. And of course, there’s Tunnelman. 

Yoshikawa’s grant from the National Science Foundation  funds the installation and maintenance of around 100 permafrost observatories around Alaska.  For each one, Yoshikawa drills into the permafrost and installs micro dataloggers with temperature sensors to measure air and permafrost temperatures on the hour. These observatories are located next to schools. Yoshikawa visits the schools, teaches students and instructors about his work and then trains them to download and analyze the data from his instruments.

Yoshikawa visits a permafrost observatory. Photo: http://www.uaf.edu/permafrost/


“Apun” is No Joke in the Arctic

February 28, 2010

Snow expert and science champion Matthew Sturm. Photo: Chris Hiemstra, Colorado State University

We’ve been meaning to catch up with Matthew Sturm for weeks now, since we know that he is about to make trail on a snowmachine adventure for science. He recently received an NSF grant to bring his snow research to Alaska’s school kids. In March he and a small team will ride from Fairbanks to Prudhoe Bay on Alaska’s north coast, travelling, sometimes on historic explorer trails, through some of the most gorgeous and remote areas of Alaska. They’ll meet with school children in the communities they pass through to share their passion for science and to teach essential concepts of physics and chemistry using snow. They also will talk about the importance of snow cover in the Arctic, and how it is changing. Stay tuned for more on this adventure.  

To go with these talks, Matthew has a new children’s book: “Apun: The Arctic Snow,” which he will present to the students. Ned Rozell recently spoke with Matthew about his new book. Here is Ned’s recent piece on Matthew and “Apun” for the Alaska Science Forum.

The "Apun" book cover. Image courtesy of University of Alaska Press.

“Apun” is a celebration of snow

By Ned Rozell

Born in Florida and raised in New Mexico, Matthew Sturm somehow became an expert on snow. During the past 30 years, he has traveled thousands of miles on the substance, counted how many grains it takes to cover a football field to a depth of two feet (1 trillion), and has spent so much time lying on his side and squinting through a hand lens that he swears he has seen molecules of water moving through the snowpack.

Now, he has written and illustrated a children’s book on snow.

“Apun:  The Arctic Snow” and its accompanying teacher’s guide are Sturm’s attempt to “bring snow to the kids.”  He works at the U.S. Army Cold Regions Research and Engineering Laboratory on Fort Wainwright.

A few years ago, he rode a snowmachine from Fairbanks to Hudson Bay, studying snow along the way. While working with editors at the University of Alaska Press for a book of essays about that journey, he proposed an idea that had long tugged at his heart–a book for kids about snow, with a nod to the Inupiaq culture of northern Alaska.

“I had written so many scientific papers that got read by just a handful of experts,” Sturm said. “A kid’s book is going to have as much of an impact as any scholarly paper I’ll write.”

Text on the book’s back cover suggests that Sturm wrote “Apun” (an Inupiaq word for the arctic snow cover) for third graders on up, but the book is a good use of time for anyone who wants to learn more about the amazing, ever-changing ground cover that’s so much a part of northern life.

“The color of the Arctic, and a lot of the subarctic, is white,” Sturm said by phone from Anchorage, where he was about to speak with a group of grade-schoolers about snow. “Snowcover is the normal state of affairs for Alaska; (Summer) is the unusual season.”

Sturm makes snow’s complexities interesting. In the teacher’s guide for “Apun,” he describes the process of sintering, during which snow–unlike sand or any other substance somewhat like snow–magically sets up from powder to concrete slab after being disturbed.

“Many of the parts in a cell phone are produced through sintering,” he writes. “Pulverized metal is packed into a mold, heated, but not hot enough to melt it, then allowed to cool. When removed from the mold, the metal will have bonded into a single mass. Snow does the same thing . . . Immediately after the winds stops blowing, the drifted snow is soft and easy to shovel, soft enough for a boot to sink into it several inches. But twenty-four hours later, after the sintering is complete, the same snow will be so hard that it is impossible to make a mark on the snow with a boot heel.”

Sturm’s book began with his own pen-and-ink sketches of weasels, snowmachines, and snow crystals.

One of Matthew Sturm's illustrations for “Apun,” this one showing the insulating value of snow. Image courtesy Matthew Sturm.

“I grew up drawing, and had to drop it as I became a professional scientist,” he said. “I joke that I wrote a kid’s book so I could be an illustrator.”

He also calls himself an “amateur linguist,” who spent many hours with Barrow elders walking outside and teasing out the complete meanings for their 70 terms for snow.

“We [Sturm and Barrow elders, including Arnold Brower Sr.] added five or six words to the list of terms for snow,” Sturm said.  He includes an Inupiaq glossary at the end of the book that informs the reader that “masallak” is best for making snowballs.

Sturm hopes his book and its teacher’s guide find their way into classrooms throughout this land of winter.

“Snow’s all around the classrooms of kids in Alaska, Canada and much of the U.S.,” Sturm said. “I’d like to think teachers wherever there is snow would find the book useful, and help them use snow right outside their classrooms to make their teaching better and more interesting.”


Arctic Stories: New Multi-Media Web site

January 21, 2010

Not your typical office. A research building at Barrow, AK. Photo courtesy Arctic Stories

We’re pleased to welcome Arctic Stories, the brainchild of Purdue University atmospheric chemist Paul Shepson, to the online effort to educate and inform people about arctic research and life. (In 2009, we supported Shepson and others working at Barrow, Alaska, on an international study called OASIS. Shepson headed an NSF-funded study of halogen chemistry.)

With children’s book author Peter Lourie, Shepson has built a multi-faceted Web site with NSF funding to present information on the science, wildlife, climate, and people of the Arctic.

The site features video interviews with natives and researchers like polar bear researcher Steven C. Amstrup of the USGS. It also showcases compelling photographs, and links to science institutions. In short, it’s another fantastic resource for following the ongoing work in the Arctic.

This is helpful as the public strives to understand the myriad messages about climate change, research, and more. With news stories reporting that the Arctic is warming twice as quickly as the rest of the planet, that sea ice is melting, and that species are losing habitat and nourishment, sites like Arctic Ice and ours aim to inform readers about the efforts being made to understand the science behind the phenomena.

The science is complex, designed to measure and help us understand changes in the atmosphere, land, plants and animals, human societies and water in the Arctic. To advance these goals, scientists conduct fieldwork in some of the most extreme environments on Earth–and their experiences are often as compelling as their data.

We encourage readers to check out Arctic Ice as they follow their curiosity about work in the far north.


Surviving the Break-up

January 19, 2010

Scientific and traditional expertise find mutual benefit in sea-ice study

By Marcy Davis

Walk on water: PI Hajo Eicken at the Barrow sea ice mass balance site in June 2008, during the melt season. All photos courtesy Matt Druckenmiller

Unlike most other solids on Earth, ice floats. As water freezes, it expands to include lots of airy pockets, which means that ice is less dense as a solid than as a liquid. Fresh water ice is relatively dense and impervious while sea ice, ice that freezes directly from mineral-rich ocean water, develops interconnected sand-to-finger-sized channels that help control its decay during warm months. Through the Seasonal Ice Zone Observing Network (SIZONET), one of about 35 National Science Foundation-funded projects in the Arctic Observing Network, Hajo Eicken, research associate Chris Petrich, and graduate student Matthew Druckenmiller (all from University of Alaska, Fairbanks, UAF), study the small-scale properties contributing to the formation and disintegration of arctic coastal sea ice. In addition to gaining a better understanding of the role of sea ice in the global climate system, Eicken’s team hopes to help coastal communities which rely on sea ice–like Barrow, Alaska–by forecasting break-up, the time of year when seasonal ice begins to melt.

Off the village of Barrow, BASC employee Michael Donovan navigates a boat to a grounded ice foe in July 2008 so that Matt Druckenmiller can take an ice core.

Off the village of Barrow, BASC employee Michael Donovan navigates a boat to a grounded ice foe in July 2008 so that Matt Druckenmiller can take an ice core.

“Sea ice provides many animals, humans included, a surface on which to live, travel, and hunt. We want to understand how sea ice decays from a materials perspective,” explains Eicken. “We also want this information to be useful to local communities for whom break-up is important for hunting and whaling. We spend time trying to understand how people in Barrow use the sea ice in their daily life so that we can define and redefine our models and projections for how the ice will behave.”

Eicken’s group studies the seasonal sea-ice zone, which includes land-fast ice (ice that freezes to the coastal shoreline) and drift ice (ice that floats on the water surface). In contrast to multiyear ice, which does not melt in the summer, seasonal ice builds up during winter months and melts in summer months. This means that seasonal ice is far less stable. From a human perspective, then, break-up can be dangerous because how the ice melts varies from year to year and progresses over the season.

UAF sea ice team conducting ice thickness measurements and ridge surveys in the landfast ice near Barrow in June 2007.

Break-up begins with melting on the sea-ice surface. If the meltwater is retained, it pools on the surface. Because of the darker color, the ice surface ponds absorb heat and create a positive feedback for even more melting.

“We study seasonal ice rather than multiyear ice because we understand far less about seasonal ice. The forces which control breakup are highly variable – sunshine and warmer temperatures, tides, and storms all contribute, but to what degree remains less clear. But from a Search and Rescue perspective, it is very important to the Barrow community to have as much information as possible during break-up, especially since the coastal land-fast ice and ice drifts have become much more unstable over the last 20 years,” Eicken says.

Chris Petrich and BASC Bear Guard Herman Ahsoak measuring level ice thickness near a grounded ridge in June 2007.

Eicken, Petrich and Druckenmiller use satellite data to map ice conditions along the coastline near Barrow where locals use established ice trails for hunting and whaling during break-up. Although satellite data provides a decent regional picture, the relatively low resolution equates to substantial real-life discrepancy. In addition to field campaigns aimed at measuring temperature and albedo of ice surface ponds and ice thickness, indigenous ice expert and ex whaling captain Joe Levitt provides daily ice observations to help integrate and ground-truth satellite and field data or break-up forecasts.

These are especially useful to local communities during spring whaling season, when hunters establish camps on the sea ice. “Matt [Druckenmiller] created maps showing ice thickness along whaling trails on the land-fast ice off Barrow. These maps have proven useful for the community who might have as many as 200 people spread out over a 20-mile area or more during whaling season. This is a big safety issue for them,” says Eicken. “We’re posting satellite and radar images along with sea ice trail maps on the Internet and holding workshops with folks in Barrow both to educate them about how to use these data as well as to help us refine our forecasting models.”

The sea ice trail maps give Barrow-area whalers important information about ice thickness around their sea-ice trails.


The (Glacial) View From Within

December 22, 2009

Before Dr. Alberto Behar of the NASA Jet Propulsion Laboratory tossed an enclosed camera into the gaping hole that bored into Jakobshavn Glacier last summer, he took a moment to listen to the roar of the river plunging into the ice.

“It sounds like a jet engine,” said Behar last week from the American Geophysical Union annual meeting in San Francisco. “If you fall in there, forget about it. You’re not going home.”

Scientists lower a probe into a moulin in the Pakisoq region in western Greenland. All photos courtesy NASA

While a human would be hard pressed to survive a “dip” in a moulin—a narrow, tubular shaft in a glacier that guides water from the surface to the glacial base—Behar and co-investigator Dr. Konrad Steffen of the University of Colorado, Boulder, are hoping to design a high-tech, video and camera-equipped probe that will. Specifically, they recently completed the fourth field season of a NASA-funded study on moulins.

Their team is developing a tool to measure the depth of moulins and, ideally, track the path of water from the surface to the ocean. The best-case scenario would be if one of the probes dropped into a moulin emerged later in the ocean and “could tell us where it had been,” said Behar in the press conference.

Behar and Steffan call their tools “expendable rovers.” The size of a pocket book, these solar-powered systems are modeled after the Antarctic Ice Borehole Probe, which studied ice streams in West Antarctica, the Amery ice shelf in East Antarctica and the Rutford ice stream in West Antarctica.

The Greenland version is modified specifically to explore the moulin environment. It consists of two high-resolution charge-coupled device cameras (a side-viewing digital camera and a downward-viewing video camera), lights, associated electronics and an inclinometer that measures the tilt of the moulin chute.

A watertight probe can withstand the immense water pressure in a moulin.

Images are sent in real time through a tether one kilometer long (about 3,300 feet) to a receiving station at the surface. The station has a video display, computer and digital tape recording devices.

Earlier this year, working in bitter cold, slushy, windy conditions (minus 10 degrees Celsius, or 14 degrees Fahrenheit), the scientists deployed the probe in two locations of a moulin. Once the probe descended to 110 meters (361 feet), it encountered horizontally flowing water and debris about one to two meters (3.3 to 6.6 feet) deep.

In this particular moulin, the water flows out in well-developed channels to the edge of the ice sheet. At the time of the experiment, the scientists measured the water flow rate of the surface melt rivers feeding the moulin at approximately 15 cubic meters a second (about 238,000 gallons a minute).

“This was very interesting and is evidence that we need an integrative plan on how to study these in a more sustainable way,” said Behar. “We need to get multi-year funding.”

Alberto Behar on the edge of a moulin in 2006.

Behar and Stefan have been developing a moulin probe since 2006, and Behar offered the following synopsis for each year of field work in the Pakisoq region.

  • 2006 The team used an ice borehole camera that shot an image about 100 meters down a Moulin. However, the camera was heavy and proved to be difficult to work with.
  • 2007 The team returned with a Sony HD video recording camera in a watertight Lexan enclosure. They sent the camera into the Moulin, but the images were hard to interpret. “It was a lot like fishing,” said Behar. “We found the crevasses are much more complex than we had thought.”
  • 2008 The team developed a simple device with a tracker GPS modem that had temperature sensors and could measure the pressure. They expected it to follow the water pathway, emerge and call home. They never heard from it again.
  • 2009 The team developed a live video feed camera system with a fiber optic cable. The camera transmitted images to special glasses (Behar calls them “Blade Runner-esque”), and the viewer could watch the camera’s progress.

“This was an exciting, important first look into a place that’s not well understood but could have an important role in understanding the dynamics of this region,” said Behar. “We’re excited by the possibilities this technology holds, not only for future studies of Earth’s icy regions, but also for future missions to explore extreme ice and liquid environments on other planets, such as the Martian polar ice caps and Jupiter’s moon Europa.”

Next year, University of Colorado scientists will use ground-penetrating radar to accurately measure the glacial ice thickness at this location. These data will help scientists better interpret their findings and plan future tests.

Scientists expect moulins to shed light on complex glacial dynamics, which are not well understood and are responding rapidly to climate change. Previous NASA measurements in the Pakisoq region using global positioning system data show the ice there moves an average of about 20 centimeters (8 inches) a day, accelerating to about 35 centimeters (14 inches) a day during the summer melt. Scientists suspect the moulins may affect—directly or indirectly—that rate of advance.

In Greenland, the surface of the ice sheet moves at varying speeds, on both seasonal and shorter-term time scales. Seasonally, glacial water penetrates to the glacier bed through significant thicknesses of cold ice. However, early in the melt season and at other times, there can be periods when water flows rapidly into glacial drainage systems, resulting in sudden new flows of water out of the glaciers. In the middle of the melt season, surface melting resumes after periods of cold weather, which can partially close sub-glacial channels.


What Lies Beneath

December 18, 2009

For years, scientists thought that melted water beneath Greenland’s coastal glaciers such as the Jakobshavn and Helheim lubricated the giant sheets of ice above, accelerating their plunge into the ocean and contributing to loss of sea ice. Turns out, that was an over-simplified explanation, said Ian Howat, assistant professor of earth sciences at Ohio State University.

Speaking in a press conference Wednesday at the annual meeting of the American Geophysical Union (AGU), the NASA-funded, CPS-supported scientist explained that the subsurface dynamics beneath glaciers is significantly more complex than previously thought.

“In the science community it’s been accepted that basal lubrication due to increased melting and warming is responsible for accelerating glacial advance and breaking off,” said Howat. “We’re finding out that’s not true.”

A calving glacier drops huge ice chunks into the sea. Photo: Martyn Clark, National Snow and Ice Data Center

Specifically, a complex, subglacial “plumbing” system involving the ocean, meltwater, and ice evolves, which drives the glacial calving. In fact, early evidence from Howat’s research suggests that ocean changes have a greater impact on the rate at which outlet glaciers spill into the sea than does meltwater.

Much of the melt water comes from early summer hot temperatures, which melt the glacier’s surface. The water flows through cracks in the ice to the ground surface.

Ian Howet in the field. Photo: Ohio State University

In the early summer, the sudden influx of water overwhelms the subglacial drainage system, causing the water pressure to increase and the ice to lift off its bed and flow faster—up to 100 meters per year, he said. The water passageways quickly expand, however, and reduce the water pressure so that by mid-summer the glaciers flow slowly again.

Inland, this summertime boost in speed is very noticeable, since the glaciers are moving so slowly in general. But outlet glaciers along the coast, such as the Jakobshavn, are already flowing out to sea at rates as high as 10 kilometers per year — a rate too high to be caused by the meltwater.

“So you have this inland ice moving slowly, and you have these outlet glaciers moving 100 times faster. Those outlet glaciers are feeling a small acceleration from the meltwater, but overall the contribution is negligible,” Howat said.

His team looked for correlations between times of peak meltwater in the summer and times of sudden acceleration in outlet glaciers, and found none. So if meltwater is not responsible for rapidly moving outlet glaciers, what is? Howat suspects that the ocean is the cause.

Through computer modeling, he and his colleagues have determined that friction between the glacial walls and the fjords that surround them is probably what holds outlet glaciers in place, and sudden increases in ocean water temperature cause the outlet glaciers to speed up.

However, Howat said meltwater can have a dramatic effect on ice loss along the coast. It can expand within cracks to form stress fractures, or it can bubble out from under the base of the ice sheet and stir up the warmer ocean water. Both circumstances can cause large pieces of the glacier to break off, and the subsequent turbulence stirs up the warm ocean water, and can cause more ice to melt.


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