HANOVER, N.H. – The U.S. Army Engineering Research and Development Center’s Cold Regions Research and Engineering Laboratory (CRREL) collaborated with the U.S. Navy during the annual Sea Ice Dynamics Experiment (SIDEx) from February through March 2020 by predicting potential breaks in sea ice.
The experiment is centered around a temporary ice camp – Camp Seadragon – that the U.S. Navy established on a sheet of ice in the Arctic Ocean. The camp serves as a temporary command center for conducting submarine operations and under-ice navigation exercises. While there are numerous dangers involved with having a training camp set up in the freezing cold, a major concern for the Navy is cracks in the sea ice.
“The experiments we’re performing are trying to measure how the ice moves and changes before it breaks, in ways that might give us the ability to see when it’s going to break before it happens,” said Dr. Chris Polashenski, a CRREL research geophysicist. “We want to use the ability to see something we can’t see with the naked eye to say where the ice is going to break and when.”
In early 2018, Polashenski did a small pilot project at the Navy’s Ice Exercise (ICEX) camp. The pilot project was focused on the research benefits associated with a new laser rangefinder instrument.
“We got this amazing new tool and wanted to see whether it was possible to measure minute stretching and shrinking in the ice that might indicate forces building up on the ice before it broke,” said Polashenski. “We just so happened to be out there at a time when we looked and said, ‘wow, that part of the ice floe is moving in a different direction than this part is. I bet it’s going to break in between those two.’ Three days later it broke, and that got everyone’s attention that this is a technique that really has some potential.”
The promising initial results from the pilot project led to a larger investment by the Office of Naval Research in a multi-institution project – the SIDEx project. SIDEx brings experts from six universities together with CRREL scientists to push the limits of measuring the way ice moves and breaks. “Our pilot was just such an ‘Ah-hah’ moment we had to follow up on it in a big way,” said Polashenski.
The new project incorporates several different laser and radar methods for measuring tiny shifts in the ice. Each new instrument is capable of observing changes of less than one millimeter over a kilometer, and some can do so from space.
By August 2018, the research project was set up as a large departmental exploration initiative led by CRREL. The laboratory has continued research at the ice camp annually in conjunction with ICEEX.
ICEX is an annual exercise that offers the Navy the opportunity to assess its operational readiness in the Arctic and train with other services, partner nations and allies to increase experience in the region, and maintain regional stability while improving capabilities to operate in the Arctic environment.
For CRREL researchers and scientists, the unique opportunity to participate in the experiment and visit the field site is enticing.
“I got into this because I wanted to do field work — that’s how Chris convinced me to come work for him in the first place,” said Dr. Nick Wright, a CRREL research physical scientist. “I never really saw myself doing something like this; I didn’t really know about this line of work until I got into it.”
Wright’s work focuses primarily on looking at sea ice cover from space. On a typical work day, he gets to task a satellite and tell it where to take pictures from his desk. Wright then develops tools to process the detailed images, which can identify cracks less than a foot wide. Each image contains numerous gigabytes of data, and Wright collects thousands of these images. Going through them by hand is impossible. Most of Wright’s day involves writing computer code to process the images. While he likes this work, he says seeing everything first hand is pretty incredible.
“I don’t know where else I would have gotten the opportunity to get in a helicopter and fly across the Arctic Ocean two hundred miles north of Alaska,” said Wright. “Just that experience of being there in person is just very visceral. On the one hand it looks like it’s just this plain white landscape without a lot going on, but when you really dig into it, there are so many different aspects of that surface to study.”
The work CRREL researchers and scientists perform during the experiment provides vital information to the Navy, delivering accurate data on the condition of the sea ice and any dangers it may present to camps and ships in the area. CRREL researchers are also seeking answers to the mysteries of how sea ice forms and moves.
“The other piece of the experiment is a very fundamental scientific piece that we don’t actually know how the sea ice breaks,” said Polashenski. “None of the large-scale models that we use to predict the drift of sea ice — either for climate scale prophecies or for just simple forecasting of ship navigation — none of those forecasts work very well right now.”
The CRREL team now has a whole list of observations they want to collect to unravel the unknowns about sea ice. In order to do this, during SIDEx 2021, CRREL scientists will set up a large array of scientific equipment at an ice camp in the Beaufort Sea with the intention of watching the ice break at the site. This phenomenon is something researchers are limited in studying at the Navy camp, which is intentionally set up on ice floes less at risk of breaking.
“We’re going to set up a camp on a floe we are almost certain is going to break,” said Polashenski. “We want to get a lot more data of the sequences of events that lead up to breakage, which will give us a much better ability to diagnose when that’s about to happen. On the Navy floe, we just don’t see as much excitement, because they are deliberately picking floes that are supposed to be not that exciting.”