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Annual Report 2016
SAMCoT
Ice ridges are key ice features both in an engineering
and geophysical context.
As more of the Arctic sea ice becomes first-year ice, a
larger fraction of the total volume will be first-year rid-
ges. First-year ridges melt more easily than old ridges
and therefore the Arctic ice cover as a whole becomes
more sensitive to global warming. Thermodynamics of
the ridges also defines their morphologic structure and
therefore their mechanical properties.
The role of ice ridges in global heat and mass balance
has not been studied extensively, and in particular
their role in a thinning Arctic sea ice cover needs to
be better quantified. SAMCoT WP1 studied ice rubble
thermodynamic processes by implementing different
scale experiments: laboratory size; small-scale and
full-scale. During March 2016, a small-scale field
experiment was performed in Svea at Lake Vallunden
(Van Mijen Fjord, Spitsbergen). This lake is connected to
the fjord through a strait and is therefore salt water and
is covered by saline ice.
Postdoc Aleksey Shestov led the experiment searching
for valuable input regarding the development of the
consolidated layer and the transformation mechanisms
of the ridge keel. PhD candidate Evgenii Salganik con-
tributed to the tests. A thermistor string was deployed
through the rubble field and conductivity sensors were
deployed at two points inside the rubble and at one
point under the rubble. Development of the consolidated
layer was monitored over a period of two weeks from
March 3rd.
At the end of the experiment the consolidated rubble
field was lifted up and samples were taken to investiga-
te the physical properties. Knowledge of these, together
with the temperature profile, will allow us to evaluate
the thermal properties and heat transfer balance.
ICE RUBBLE SMALL-SCALE
EXPERIMENT
Pictures of the small-scale field experiment in Svea at Lake Vallunden (Van Mijen Fjord, Spitsbergen).
Consolidated layer and loose rubble at the end of the experiment.