(on the western shore, across from Kenai) had to be
but it will usually float free from the bottom before
suspended for a day due to heavy ice. Operators were
reaching about 0.5 m (1.6 ft) in thickness (Blenkarn
forced to cast off and spend the night offshore, as it
1970). At the point where buoyancy overcomes the
was feared that ice propelled by the tidal current would
bond strength, the ice lifts free and takes with it the
cause their vessels to be ruptured on the pier. The same
topmost layer of sediment. This mechanism is the rea-
news article mentioned a tanker-puncture incident in
son for much of the black coloration typical of the ice
1988 resulting in a small crude oil spill that was caused
found in the Upper Inlet. The newly freed ice then
by similar conditions at the off-loading terminal at
either drifts into deeper water and continues growing
Nikiski (Kizzia 1990). Later that year, in December,
or melting in the same manner as pack ice, or is floated
Wohlforth (1990) wrote that heavy ice and currents
higher on the beach, where it becomes stranded again
stripped the MV Coast Range from the Drift River
and continues growing as "stamukha."
pier during loading operations, resulting in another
spill estimated at 0.752.3 m3 (200600 gallons). In
3.1.3 Stamukha
February 1999, moving ice pushed the MV Ocean
The term "stamukhi," the plural of stamukha, origi-
Laurel into Unocal's dock at Nikiski, causing 0,000
nated from the Russian ice classification and refers to
in damage to the dock and catwalk (Associated Press
sea ice that has broken and piled upward, or
1999). A week later, heavy ice conditions in the Lower
hummocked, because of wind, tides, or thermal ex-
Inlet cracked a cargo storage tank aboard the MV
pansion forces. Under certain conditions, massive ice
Chesapeake Trader (Little 1999, ADEC 1999), allow-
blocks can form through
ing a spill of approximately 1.6 m3 (420 gallons). In
January 2000, ice clogged the cooling-water intake of
Repeated wetting and accretion of seawater,
the freighter MV Torm Pacific, causing a brief loss of
Crushing and piling consolidation, or
power and necessitating retreat to less troublesome
Stranding of successive layers of floating ice cakes
waters until conditions improved (Little 2000a). A
on top of others, which, in turn, freeze together.
week later, two more vessels that were taking on urea
and fuel were stripped from Tesoro's and Unocal's
The term has appeared in numerous publications re-
docks in Nikiski. One of the ship's pilots stated that
ferring to the very largest ice cakes that are character-
the ice was "fairly soft but massive, about a foot and a
istic of Cook Inlet. Smith (2000) provided a detailed
half thick [0.5 m]... some of the pans are two miles in
description of the stamukha formation process as be-
diameter [3200 m]." Approximately 0.75 m3 (200 gal-
ginning with the formation of beach ice. That is, in-
lons) of gasoline were spilled as tide-borne ice over-
coming tide water forms thin, bottom-fast ice on cold-
whelmed the mooring cables and tugboats that were
soaked mud flats. High tides deposit floating cakes
attempting to hold them in place. The Coast Guard
and brash atop the bottom-fast ice, where they become
suspended cargo transfer there for several days until
stranded by the ebbing tide. Alternatively buoyancy
the ice conditions subsided (Little 2000b).
may break loose some of the bottom-fast ice pieces so
that they become stranded atop other sections of ice
3.1.2 Shorefast ice
that are still adhered to the mud when the tide again
Ice that forms and remains firmly attached to the
recedes. The stacked pieces then freeze together and
shoreline, stationary structures, or other nonmoving
become increasingly stronger as a unified mass.
ice is known as "fast ice." It can form directly from
Stamukhi in Cook Inlet were reported by Nelson
freezing of the surrounding water, from piling and sub-
(1995) as thick as 7.5 m, and up to 12.2 m (40 ft) thick
sequent re-freezing of brash ice or broken ice of any
by Hutcheon (1972b) and Gatto (1976). Blenkarn
age, or from flooding of snow atop shorefast ice.
(1970) described the typical stamukha as 4.6 m (15 ft)
Because of the large tidal range, extensive areas of
high and 6.1 m (20 ft) in diameter. Because of their
mudflats around Cook Inlet are exposed to air tem-
large size, beached stamukhi are the last remnants of
peratures low enough to freeze the upper layers of mud.
the ice cover to be seen in late spring. Tidal action
With the flood tide, the seawater in contact with the
occasionally will free stamukhi from the beach, float-
frozen mud can freeze and bond to the bottom, form-
ing them into deeper water where they can entrain with
ing beach ice. Successive low tides allow the stranded
the pack ice. Because of their large mass and relative
ice to attain ambient air temperature. When the air tem-
strength, drifting stamukhi are hazardous to shipping.
perature is significantly lower than the seawater tem-
In the brash ice conditions that are common in Cook
perature, the ice can become progressively thicker with
Inlet, stamukhi are sometimes difficult to distinguish.
each succeeding high tide. As much as 2.5 cm (1 in.)
They are, however, readily distinguishable among level
of ice per tidal flood can accumulate in this manner,
ice floes because of their higher freeboard and irregu-
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