with the atmospheric air temperature and pressure time series), compared to the
other Arctic seas [11] and, to a high degree, are controlled by the intensity and
redistribution of river runoff [8].
Studies of Laptev Sea fast ice began almost simultaneously with the establishing
of the polar station network in the Arctic in the 1930s, and continue through the
present time. The bibliography of relevant papers, focused primarily on phenomenological descriptions and features of the fast ice regime in the Laptev Sea, is
a list hundreds long. Since the late 1970s, a substantial portion of these studies has
been devoted to mathematical modeling of fast ice. Among recent studies, we
should mention a paper by [29], who examined the annual evolution of fast ice in
the Laptev Sea. Despite imperfect reproduction of the atmospheric precipitations in
the reanalysis model used in the performed simulations as forcing, the authors
estimated fast ice growth rates by applying different values for heat fluxes from the
sea to the bottom of the ice and the surface albedo. The authors came to the obvious
conclusion about the substantial effect of these parameters on the rates of ice
thickness changes.
The freezing of bottom sediments in the Laptev Sea has been much less studied
than water layer freezing in the coastal areas of the sea. Despite the urgency for
understanding of sediment layer freezing/melting processes, in particular, for
quantifying the rates and volume of methane release from the eastern Arctic seas
(see [23, 24] for details), and numerous applied (engineering) aspects of this
problem [3], our knowledge of under-sea ground thermodynamics is still fragmentary. For example, until recently only spatial distributions of various types of
deposits, concurrent with general information about their thermo-physical properties were available in the Laptev Sea [15]. The situation was improved by the
implementation of international projects on the study of underwater permafrost by
drilling from immobile ice [10, 18, 21]. Up to now, the most detailed studies of
bottom sediments at the Laptev Sea shelf have been around the River Lena delta
and the western part of the Buor-Khaya Bay, near the Tiksi township [5, 6]. These
studies suggest that bottom soils can stay both in a cooled state (without inclusions
of ice) and partly or completely frozen. In addition, they have analyzed the first
reliable data on the composition, cryogenic structure, and thermophysical properties
of samples of frozen and thawed soils and their changes to depths exceeding 50 m.
Despite the availability of experimental data, mathematical models of heat and
salt transfer in bottom soils are rare; the available ones, as a rule, do not describe the
interactions and feedbacks of the energy and mass transfers in the boundary layers
of the sea, atmosphere, and bottom [9]. In addition, there is no common view about
the mechanisms playing a role in bottom sediment freezing [30]. For instance, it is
believed that this bottom freezing begins only after the complete freezing of the
overlying water column, notwithstanding reported evidence for the opposite point
[13] for discussion.
In this contribution, we describe the fast ice formation and seasonal freezing of
the sub-water ground layer in the Tiksi Gulf (a coastal part of the Buor-Khaya Bay)
during the winter of 2014–2015 based on joint analysis of experimental data,
theoretical studies, and modeling. For assessment of the effects of fast ice growth on
612
P. V. Bogorodskii et al.
other Arctic seas [11] and, to a high degree, are controlled by the intensity and
redistribution of river runoff [8].
Studies of Laptev Sea fast ice began almost simultaneously with the establishing
of the polar station network in the Arctic in the 1930s, and continue through the
present time. The bibliography of relevant papers, focused primarily on phenomenological descriptions and features of the fast ice regime in the Laptev Sea, is
a list hundreds long. Since the late 1970s, a substantial portion of these studies has
been devoted to mathematical modeling of fast ice. Among recent studies, we
should mention a paper by [29], who examined the annual evolution of fast ice in
the Laptev Sea. Despite imperfect reproduction of the atmospheric precipitations in
the reanalysis model used in the performed simulations as forcing, the authors
estimated fast ice growth rates by applying different values for heat fluxes from the
sea to the bottom of the ice and the surface albedo. The authors came to the obvious
conclusion about the substantial effect of these parameters on the rates of ice
thickness changes.
The freezing of bottom sediments in the Laptev Sea has been much less studied
than water layer freezing in the coastal areas of the sea. Despite the urgency for
understanding of sediment layer freezing/melting processes, in particular, for
quantifying the rates and volume of methane release from the eastern Arctic seas
(see [23, 24] for details), and numerous applied (engineering) aspects of this
problem [3], our knowledge of under-sea ground thermodynamics is still fragmentary. For example, until recently only spatial distributions of various types of
deposits, concurrent with general information about their thermo-physical properties were available in the Laptev Sea [15]. The situation was improved by the
implementation of international projects on the study of underwater permafrost by
drilling from immobile ice [10, 18, 21]. Up to now, the most detailed studies of
bottom sediments at the Laptev Sea shelf have been around the River Lena delta
and the western part of the Buor-Khaya Bay, near the Tiksi township [5, 6]. These
studies suggest that bottom soils can stay both in a cooled state (without inclusions
of ice) and partly or completely frozen. In addition, they have analyzed the first
reliable data on the composition, cryogenic structure, and thermophysical properties
of samples of frozen and thawed soils and their changes to depths exceeding 50 m.
Despite the availability of experimental data, mathematical models of heat and
salt transfer in bottom soils are rare; the available ones, as a rule, do not describe the
interactions and feedbacks of the energy and mass transfers in the boundary layers
of the sea, atmosphere, and bottom [9]. In addition, there is no common view about
the mechanisms playing a role in bottom sediment freezing [30]. For instance, it is
believed that this bottom freezing begins only after the complete freezing of the
overlying water column, notwithstanding reported evidence for the opposite point
[13] for discussion.
In this contribution, we describe the fast ice formation and seasonal freezing of
the sub-water ground layer in the Tiksi Gulf (a coastal part of the Buor-Khaya Bay)
during the winter of 2014–2015 based on joint analysis of experimental data,
theoretical studies, and modeling. For assessment of the effects of fast ice growth on
612
P. V. Bogorodskii et al.