Oceanography | Vol. 38, No. 4
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We report here on 12 seasons of operational experience with
hovercraft in both polar regions. Table 1 summarizes the scientific
activities in the Arctic Ocean using Sabvabaa, and details of the
scientific results from Arctic Ocean expeditions can be found in
the online supplementary material.
OPERATIONS OVER SEA ICE IN THE
ARCTIC OCEAN
Griffon TD2000 hovercraft operations in the Arctic Ocean from
2008 through 2020 covered 26,551 km, of which about 5,300 km
was over sea ice (Table 1, Figure 3). In addition, about 2,460 km was
covered in ice drift mode. The activity included 19 unsupported (no
refueling) and two supported successful trips from Longyearbyen,
Svalbard (78°N), into the sea ice cover north of 80°30'N. Each
unsupported trip started and ended with an open ocean transit of
about 170 km. The longest unsupported trip out of Svalbard lasted
three weeks and reached a distance of 150 km north of the ice edge.
In addition to the 21 roundtrips (Figure 3) made from
Longyearbyen (78°N) to an L-shaped target area on the Yermak
Plateau (>80°30'N), the main scientific endeavors undertaken
with the hovercraft were a three-month-long trip from Svalbard
to Gakkel Ridge at 85°N in 2012 and a 12-month ice drift in the
central Arctic Ocean in 2014/15. The icebreaker Oden accompa-
nied the hovercraft in 2012. The target was Lomonosov Ridge, but
the trip had to be aborted at Gakkel Ridge due to consistent poor
light conditions and, eventually, time constraints. The return from
Gakkel Ridge was with the icebreaker Polarstern. The subsequent
2,200 km, 12-month-long ice drift Fram-2014/15 was a joint ven-
ture between the German Alfred Wegener Institute for Polar and
Marine Research and the Norwegian Nansen Environmental and
Remote Sensing Center (Kristoffersen et al., 2016). Two support
missions by a Norwegian Coast Guard P-3 Orion aircraft, and
overflights by a Challenger CL-604 aircraft of the Danish Arctic
Command, contributed to maximizing the scientific outcome of
the endeavor. This is the longest drift on sea ice ever undertaken by
Western scientists. Figure 4 provides an overview of the scientific
activity and ice dynamic events during the ice drift.
HOVERCRAFT CONSIDERATIONS OVER SEA ICE
On sea ice in the Arctic Ocean, the efficiency of travel, or traffic
ability (Hibler and Ackley, 1974), reflects the degree of ice defor-
mation manifested by the number of pressure ridges that must
TABLE 1. Overview of the operations and scientific activities undertaken using the hovercraft Sabvabaa. A list of publications related to hovercraft science
operations is provided in the online supplementary material.
ARCTIC OCEAN
ANTARCTICA
2008
2009
2010
2011
2012
2013
2014/15
2020
2022/23
2023/24
2024/25
OPERATIONS
Trips north of 80°N
Total distance (km)
6.100
5.740
3.840
3.655
1.407
1,000
2,200
772
407
970
2,660
Travel over sea ice (km)
431
1.174
880
792
1.133
117
773
Distance north of the ice edge (km)
13
59
131
154
481
Passive drift mode (km)
260
2,200
Distance without refueling (km)
755
676
737
787
581
772
Fuel consumption
60 l/hr
60 l/hr
60 l/hr
60 l/hr
60 l/hr
60 l/hr
1 l/km
1 l/km
1 l/km
Economy speed (km/hr)
35
35
35
35
35
35
40–60
40–60
40–60
SCIENTIFIC ACTIVITIES — MEASUREMENTS
Sea ice thickness (km)
200
30
600
Ice radar (km)
25
580
CTD stations
10
57
36
Seismic reflection (km)
10
35
35
44
1,000
260
166
Sediment cores
17
Rock dredges
10
Bottom camera stations
24
Acoustic plankton stations
29
Wave buoy deployments
15
Bathymetry buoy deployments