A curious Adelie penguin stands near the Coast Guard Cutter Polar Star on McMurdo Sound, Antarctica, Jan. 7, 2016. Photo Credit: USCG
By: Ashley Postler, Columnist
Despite predictions that the Arctic Ocean will be ice-free during the late-summer months by 2040,[i] there remains a need for the U.S. to maintain icebreaking capabilities in order to protect its sovereignty and interests in the Arctic. Congressional funding to update the nation’s aging fleet of polar icebreakers has been slow to materialize, prolonging the delivery of new vessels which take approximately a decade to build.[ii] Consequently, the U.S. Coast Guard (USCG), which undertakes ice breaking missions at both poles, faces a looming gap in its ability to provide maritime domain awareness (MDA) and patrol US territory in the Arctic. Further, this capabilities gap extends to conducting search and rescue (SAR) operations and supporting scientific research. To offset the fleet’s declining capabilities in the wake of delayed delivery of new icebreakers, the US government should explore alternative methods of icebreaking which will likely have outpaced and replaced these new vessels by the time they enter into service.
Currently, the USCG operates one heavy and one medium polar icebreaker, Polar Star and Healy, respectively. Acquired in 1976, the latter is now well beyond its intended 30-year service life thanks to significant repair work and a supply of replacement parts from another heavy icebreaker, Polar Sea, which was decommissioned in 2010 due to catastrophic engine failure. Plans to modernize Polar Star to further extend its service life or to reactivate Polar Sea were deemed too costly.[iii] Consequently, the USCG and U.S. Navy (USN) are collaborating to update the USCG’s polar fleet by investing approximately $9.8 billion in life-cycle costs for the acquisition, operation, and maintenance of three new heavy icebreakers.[iv]
However, icebreaking is no longer the sole answer to providing Arctic MDA, which is partially achieved by USCG patrols conducted on the water. In the Arctic, this necessitates an ice-free path for USCG vessels to traverse. However, MDA can and is being achieved more purposefully under and over the water. The USN states that even the complete loss of icebreaker support would only minimally impact its ability to monitor and provide MDA in the Arctic.[v] This is because, in addition to submarines, the USN already deploys unmanned underwater vehicles/unmanned surface vehicles (UUV/USV)[vi] that utilize swarm AI technology, such as the SwarmDiver,[vii] in support of reconnaissance and MDA.
Research and SAR operations, both of which currently require a physical path through the ice, can also be accomplished either without breaking ice, or breaking it in more efficient and agile ways. For example, amphibious hovercraft can travel over water and ice far quicker than conventional marine vessels and can operate in difficult conditions such as heavy fog. While susceptible to “side slipping forces,”[viii] hovercraft can operate on unbroken ice with far superior maneuverability than can traditional icebreakers moving through ice. There is thus potential for research missions to travel further and faster without even having to break ice. This is especially critical for SAR operations for which expediency is necessary, and when the vessel must get very close to the object,[ix] neither of which are best served by traditional icebreaking.
Furthermore, although hovercraft have less icebreaking capabilities compared to traditional icebreakers,[x] along icy surfaces, the former propel at speeds of up to 90 kilometers per hour.[xi] The resulting vibrations create waves, known as flexural gravity waves,[xii] which form below the surface and oscillate across the bottom of the ice, causing it to snap.[xiii] Also, importantly, given that hovercraft leave no underwater pressure signature, marine life is undisturbed.[xiv] The Resonance method of ice destruction, whose origins for use in amphibious hovercraft date back to the 1980s,[xv] is currently employed by the Canadian Coast Guard to break ice along the St. Lawrence River.[xvi]
Additionally, submarines have been able to break through surface ice since at least the 1950s,[xvii] and are currently capable of breaking through approximately three meters of ice[xviii] by slowly rising to apply continuous and firm pressure upon the ice from below until it breaks.[xix] While still in the early stages, there is much potential for submarine icebreaking to play a critical role in situations that necessitate carving a path through the ice, such as for military and SAR operations. The surface ice’s reflective contoured canopy compounds the effects of the undersea marine environment.[xx] These unique acoustics provide an opportunity to further explore resonance icebreaking as an alternative to traditional icebreaking. In this regard, researchers at Russia’s Sholem-Aleichem Priamursky State University[xxi] aim to generate flexural-gravity waves from below the surface[xxii] to break ice, rather than from above like hovercraft.
Such research indicates that submarine pathbreaking through ice is possible. Submarines traveling at a depth of 30 meters below the surface can break ice up to one meter thick; at a depth of 20 meters, a submarine is capable of carving a path through two meters of ice, the same as the US heavy icebreaker Polar Star moving at three knots, but at ten times that speed.[xxiii] Outfitting submarines to not only break ice but also carve a path through it is a meaningful step toward replacing traditional icebreakers.
The strength of other nations’ traditional icebreaking fleets are often compared to that of the U.S., which is obviously aging and quickly diminishing. This comparison, which falls prey to “icebreaker envy”[xxiv] is used to argue for the addition of new—and expensive, time-consuming and cumbersome—icebreakers to the US polar fleet.[xxv] Such arguments obscure the reality that although the need for unrestricted access to US Arctic territorial waters regardless of ice conditions remains, despite global warming trends, traditional icebreaking is potentially becoming an outdated method of doing so.
[i] Kate Ravilious, “Late-summer Arctic sea ice could disappear by 2040,” Physicsworld.com, November 8, 2018, https://physicsworld.com/a/late-summer-arctic-sea-ice-could-disappear-by-2040/
[ii] Heather A. Conley, “To Build or Not to Build an Icebreaker? That is the $1 Billion Funding Question,” Center for Strategic and International Studies, September 1, 2015, https://www.csis.org/analysis/build-or-not-build-icebreaker-1-billion-funding-question
[iii] Ronald O’Rourke, “Coast Guard Polar Security Cutter (Polar Icebreaker) Program: Background and Issues for Congress,” Congressional Research Service, October 26, 2018, https://fas.org/sgp/crs/weapons/RL34391.pdf
[v] “Acquisition Chief: Loss of Icebreaker Would Have ‘Minimal Impact’ on Navy,” Miltary.com, DoDBuzz, September 7, 2016, https://www.military.com/dodbuzz/2016/09/07/acquisition-chief-loss-of-icebreaker-would-have-minimal-impact-on-navy
[vi] Shane Hickey, “The innovators: the swarm of sea drones sniffing out drugs and mines,” The Guardian, January 31, 2016, https://www.theguardian.com/business/2016/jan/31/the-innovators-hydroswarm-sea-drone-sniffing-out-drugs
[vii] Geoff Fein, “Navy League 2018: Aquabotix adds the SwarmDiver USV to its family of systems,” Jane’s 360, April 10, 2018, https://www.janes.com/article/79165/navy-league-2018-aquabotix-adds-the-swarmdiver-usv-to-its-family-of-systems
[ix] Neoteric Hovercraft, “How do airboats compare to hovercraft?” Neoteric Hovercraft Blog, May 7, 2012, http://neoterichovercraft.blogspot.com/2012/05/how-are-airboats-different-than_07.html
[x] Griffon Hoverwork, 2013.
[xi] CTV Montreal, “Hovercraft takes aim at thick St. Lawrence ice,” April 4, 2015, https://montreal.ctvnews.ca/hovercraft-takes-aim-at-thick-st-lawrence-ice-1.2311958
[xii] P.A. Milewski and Z. Wang, “Three Dimensional Flexural–Gravity Waves,” Studies in Applied Mathematics, pp. 1-14, (Massachusetts Institute of Technology: 2013), https://core.ac.uk/download/pdf/9708595.pdf
[xiii] CTV Montreal, 2015.
[xiv] Griffon Hoverwork, 2013.
[xv] Kornev, A.A., Krestyaninov V.F. Levschanov L.P. Ryabinkin A.B. Full-scale study of ice fracture resonance method amphibious hovercraft / Design Considerations vessels in ice. Intercollegiate Sat Scient. Proceedings .- 1988 .- Gorkiy p. 107-117.
[xvi] CTV Montreal, 2015.
[xvii] Dan Joling, “Navy starts under-ice submarine exercise off Alaska’s coast,” phys.org, March 8, 2018, https://phys.org/news/2018-03-navy-under-ice-submarine-alaska-coast.html
[xviii] David Hambling, “How the Navy Punches a Nuclear Sub Through Arctic Ice,” Popular Mechanics, April 5, 2018, https://www.popularmechanics.com/military/navy-ships/a19681544/how-a-submarine-surfaces-through-ice/
[xx] Cmdr. Corey B. Barker, “Submarines USS Hartford, USS Connecticut Surface Together in the Arctic Circle,” US Navy, March 13, 2018, https://www.navy.mil/submit/display.asp?story_id=104692
[xxi] “The quickest way to break the ice is by submarine,” The Economist, April 12, 2017, https://www.economist.com/science-and-technology/2017/04/12/the-quickest-way-to-break-the-ice-is-by-submarine
[xxii] Kevin MgWin, “Wave technology is one-two punch for ice-breaking,” Arctic Today, April 5, 2018, https://www.arctictoday.com/wave-technology-one-two-punch-ice-breaking/
[xxiii] The Economist, 2017.
[xxiv] Craig H. Allen Sr., “Addressing the US Icebreaker Shortage: Part 2,” Pacific Maritime Magazine, December 1, 2017, https://www.pacmar.com/story/2017/12/01/features/addressing-the-us-icebreaker-shortage-part-2/567.html