Ice Shelf Flow and Fracture Dynamics

What Are They Doing?

Pressure ridges form ice formations on the Ross Ice Shelf, Antarctica. Photo by Gary Wesche.Pressure ridges form ice formations on the Ross Ice Shelf, Antarctica. Photo by Gary Wesche. The objective of our project is to understand the behavior of the McMurdo Shear Zone (SZ) in Antarctica through a four year integrated study involving field observation, satellite remote sensing, and numerical modeling. The SZ is a section of heavily crevassed ice that separates the slow-moving McMurdo Ice Shelf (MIS) from the larger fast-flowing Ross Ice Shelf (RIS). Previous mapping of crevasses in the SZ indicates the potential for unstable behavior. Our project will carry out GPS surveys to study the surface deformation across the SZ and Ground Penetrating Radar surveys (GPR) to obtain detailed maps of crevasse extent and orientation. Because the shear zone is intensely crevassed, and hence dangerous for surface travel, we will perform the GPR surveys using an autonomous robot. The field observations will be used to develop a numerical model of the shear zone’s behavior and simulate future scenarios of its influence on ice shelf stability.

The SZ provides a critical amount of lateral support for the RIS. A potential weakening of this area could reduce the amount of backstress provided by the RIS on inland ice which would increase the flux of ice across the grounding line and thereby accelerate the ice sheet’s contribution to sea level rise. Logistic support of the US Antarctic Program’s South Pole station also relies on an overland traverse from McMurdo which must cross the SZ. Our work will provide a means of predicting future SZ behavior and provide a timeframe to plan alternative routes if necessary.

Where Are They?

A view of McMurdo Station, Antarctica. Photo by Michael League.A view of McMurdo Station, Antarctica. Photo by Michael League. Our camp is located on the edge of the McMurdo Shear Zone approximately 50 km from McMurdo Station. Living conditions include tent camping in extreme cold while in the field, and shared facilities while transiting McMurdo. Each group member has their own private tent for sleeping; two larger communal tents serve as a kitchen/gathering space, and scientific workshop. The teacher will participate in day to day camp chores including cooking, cleaning, field repairs, and vehicle maintenance. The only forms of communication at base camp are satellite phone and radio. However, there will be internet access at McMurdo Station before and after the time at field camp.


Time to fly
After a two week break in New Zealand, I have returned to the United States and to Timberline, my home school. I have to say it feels odd to be here after two months away and my mind continues to drift back to Antarctica and all of the high and lows of my time there. Antarctica is an amazing, astounding place, a place that is relatively untouched by humans and is a natural laboratory for all ranges of science – including the 600,000 sq. miles of Ross Sea that was protected on October 28. It has been protected by its remoteness for decades during the Age of Exploration – but as our...
Phoenix Airfield First Landing
The runways at McMurdo Station in Antarctica are vital to mission of the NSF and USAP – without them, the program just wouldn't work. Getting personnel and equipment (not only for the U.S. but also for New Zealand and Italy, as well as various other countries periodically) would not be as easily possible without the airfields and the hard work of the U.S. Air Force and Reserves. In the November 4th blog post, I discussed the development and challenges of the various runways that support the operations down in the far South. Today, November 15th, marks the first time that a aircraft landed...
Runways of McMurdo
In early August of this year, Chicago O'Hare broke ground on their newest East-West runway at 11,245 ft and 200 ft wide – it will the second longest at O'Hare and will continue to expand the service at one of the nation's busiest airports. It's not often that a runway gets built – runways are often refurbished, lengthened, or improved it other ways – but altogether new ones? Nope, just not that often any more. In the realm of "not that often" anything that gets done in Antarctica is "not that often" – but building a runway down here falls at the far end of that category in the "almost...
Gordon Hamilton
This journal entry was written a number of weeks ago and is only now being posted (Nov. 12). It has been a long few weeks dealing with the loss of Gordon, but I wanted to finally share my thoughts on his passing and the man. On Saturday, October 22nd, after a day in the field with Gordon, Lynn, and Peter, we were returning to the Shear Zone camp when unexpectedly tragedy befell our group when Gordon Hamilton and his snowmobile fell into a deep crevasse in the Shear Zone. The fall was fatal and we have lost a friend, colleague, father, husband, teacher, and so many other things. It has...
Weddell seal range
Okay so my friends will say (and I will admit) that I'm not exactly the most touchy-feely guy out there, but today I headed out to Turtle Rock and Hutton Cliffs to get an idea what the team from Montana State University has been up to while doing the Weddell seal census – one of the longest Antarctic projects, having been started in 1968. Any attempt to not be touchy-feely would be ridiculous after having seen this ... so bear with me and enjoy the experience. The Weddell Seal Population Study Studied since 1968, the Erebus Bay population of Weddell seals is the southernmost breeding...

Expedition Resources

Project Information

30 September 2016 to 26 November 2016
Location: McMurdo Station, Antarctica
Project Funded Title: Collaborative Research: Flow and Fracture Dynamics in an Ice Shelf Lateral Margin: Observations and Modeling of the McMurdo Shear Zone

Meet the Team

David Thesenga's picture
Timberline PK-8
Longmont, CO
United States

David Thesenga has been teaching physics, chemistry, and the earth sciences for 16 years to both middle- and high-school students in Pasadena, New York, Chicago, and Longmont, Colorado. From watching the eruption of Mt. St. Helens to climbing the Cascades, growing up in Oregon fueled his interest in the world around him and a desire to understand how his landscape was formed. With an original interest in glaciology, David earned his BS in Geology/Geophysics from the University of Alaska Fairbanks and shifted to the mining industry in Cripple Creek, Colorado. After leaving mining, he earned his Masters of Science in Teaching from Boston College and never looked back. He has been a curriculum developer for the 7-10 Project of the California PreCollege Science Initiative (CAPSI) at the California Institute of Technology, a faculty associate for math and science teacher preparation at Claremont Graduate University, and is currently the editor of The Earth Scientist, the journal of the National Earth Science Teachers Association. He was most recently named an Albert Einstein Distinguished Educator in 2013/14 and worked for the National Science Foundation in the Directorate of Geosciences focusing on 3D printing of topographical concepts and assisting in the reimagining of the GLOBE program's teacher professional development.

Lynn Kaluzienski's picture
University of Maine
Orono, ME
United States

Researcher Lynn Kaluzienski is a PhD student at both the School of Earth and Climate Sciences and Climate Change Institute at the University of Maine. She received her Bachelor's of Science in Physics and Astronomy at Emory University in 2014. Since then she has strived to apply her background in physics to problems within the Cryosphere. She currently researches the dynamics of ice shelf margins and calving fronts and their effects on ice shelf stability.

Gordon Hamilton's picture
University of Maine, Dept. of Earth Sciences and the Climate Change Institute
Orono, ME
United States

Gordon Hamilton is a Professor with a joint appointment in the School of Earth and Climate Sciences and the Climate Change Institute at the University of Maine. Dr. Hamilton studies ice sheet mass balance and the role of ice sheets in modulating global sea levels. Current research focuses on understanding the dynamics of outlet glaciers and ice shelves in Greenland and Antarctica, ice-ocean interactions in Greenland, snow distribution across the polar ice sheets. This work involves field experiments, satellite remote sensing and numerical modeling. Prior to arriving at UMaine, he was a research scientist at Ohio State’s Byrd Polar Research Center and the Norwegian Polar Institute. He received his PhD in Geophysics from the University of Cambridge.

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Latest Comments

Thanks for participating in Antarctica Day 2016 and for your insight as well as additional information on the Antarctica Treaty. Again, welcome back and that's a pretty cute seal pup!
Thank you for the wonderful tribute to Gordon with the emphasis on science and risks. No one looks to have an accident, and they are just that accidents. A life well lived is never lost, but...
David, Thank you for this journal entry. We all know Gordon as a person and the value and importance of his work so much better than any of the other articles were able to convey. Well said.
David - thank you for sharing your Thoughts on Gordon. I imagine this was not an easy journal to write and publish, but his message and memory are important to share!
300 lbs. in 35 days--Holy cow! I wonder how that compares to other mammals--say a whale. That's amazing!