Tidal ice drift and ice-generated changes in the tidal dynamics/energetics on the Siberian continental shelf

Каган, Б. А.; Romanenkov, D. A.; Sofina, E. V.

doi:10.1016/j.csr.2007.09.004

Cited by 14 publications

(9 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While significant progress has been achieved in understanding the formation of the surface and bottom water layers [e.g., Steele and Ermold , 2004; Dmitrenko et al , 2005a; Bauch et al , 2009; Dmitrenko et al 2010b, 2011], the vertical exchange across the SHL remains poorly understood. Numerical models suggest that lunar semidiurnal tides (M 2 ) with a period of half a lunar day (12 h and 25.2 min) are likely to be among the most energetic high‐frequency motions on the Siberian shelf [e.g., Kowalik and Proshutinsky , 1994; Kagan et al , 2008]; however, little is known about Siberian shelf tidally driven water dynamics and mixing. When the barotropic tide interacts with rough bottom topography, internal waves may be generated with similar tidal frequencies.…”

Section: Introductionmentioning

confidence: 99%

Tide‐induced vertical mixing in the Laptev Sea coastal polynya

et al. 2012

View full text Add to dashboard Cite

[1] Enhanced semidiurnal-band velocity shear across the shelf halocline layer (SHL) was found during land-fast ice edge mooring-based acoustic Doppler current profiler (ADCP) and conductivity-temperature-depth (CTD) observations over the eastern Laptev Sea shelf ($74 N, 128 E) in April-May 2008 and April 2009. In 2008, the major axis amplitude for the lunar semidiurnal M 2 tidal ellipses demonstrated intermediate maximum in the SHL at 11-13 m (15 AE 3 cm/s), gradually decreasing to subice and near-bottom layers to $9 AE 3 cm/s (at 7 m) and 7 AE 2 cm/s (at 19 m), respectively. In 2009, the semidiurnal tidal flow exhibited similar patterns, but velocities were reduced by about factor of 2. Our estimates of gradient Richardson numbers suggest that the velocity shear associated with semidiurnal baroclinic tidal flow may be strong enough to play a role in water mass modification, promoting shear instabilities, turbulence, and vertical mixing of seawater properties across the SHL. This suggestion is consistent with near-homogeneous water layers episodically occurring in the SHL. Differences in the background stratification and local tidal dynamics between 2008 and 2009, together with rapid responses of the semidiurnal motion to polynya openings, suggest that the baroclinic tide is locally generated.

show abstract

Section: Introductionmentioning

confidence: 99%

Tide‐induced vertical mixing in the Laptev Sea coastal polynya

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Existing studies either show observed tidal variations alone [e.g., Prinsenberg and Hamilton, 2005] or model results without comparison with seasonal observations [Kagan et al, 2008]. The precise role of the ice-ocean stress in the observed tidal variations is thus unclear.…”

Section: Introductionmentioning

confidence: 99%

On the modification of tides in a seasonally ice‐covered sea

2008

View full text Add to dashboard Cite

[1] New observations from eight moorings located in Foxe Basin, Hudson Strait, and Hudson Bay are used to study the seasonal variability of the M 2 tide. Significant seasonal variations of the M 2 surface elevation are found in all these regions and at all seasons. The largest variations occur during winter while both elevation increase (Hudson Strait) and decrease (Hudson Bay, Foxe Basin) are observed. These variations are found recurrent at the stations where multiyear observations are available. Observations from a velocity profiler are consistent with a seasonal damping of the tides because of friction under ice. Numerical simulations with a sea ice-ocean coupled model and realistic forcing qualitatively reproduce most of the features of the observed variability. The simulations show that the winter M 2 variations are essentially caused by the under-ice friction, albeit with strong regional differences. Under-ice friction mostly occurs in a limited region (Foxe Basin) and can account for both increased and decreased M 2 elevations during winter.

show abstract

“…The ice presence is taken into account in the heat exchange with the atmosphere and by adding freshwater due to ice melting. The modelling results by Kagan et al (2008a), as well as Kagan and Sofina (2010), show that drifting ice causes minor change in tidal maps in the region. The changes in amplitude do not exceed 1-3 cm, which is less than the root mean square of absolute errors of model equal to 3.8 cm in the absence of sea ice when the observations are available.…”

Section: Introductionmentioning

confidence: 89%

“…The open boundary was drawn so as to avoid the amphidromes in its close vicinity. Their positions were estimated from the tidal map simulated by Kagan et al (2008a) and Sofina (2008).…”

Section: Model and Meshmentioning

confidence: 99%

Impact of wind and tides on the Lena River freshwater plume dynamics in the summer season

et al. 2015

View full text Add to dashboard Cite

The Lena plume dynamics in the Lena Delta region of the Laptev Sea are explored in simulations performed with the Finite Volume Coastal Ocean Model (FVCOM) on a mesh with the horizontal resolution 0.4-5 km. The impact of wind and tides on the Lena plume propagation is analysed based on simulations for the summer season of 2008 and also on idealised experiments. All main Lena River freshwater channels (Trofimovskaya, Bykovskaya, Tumatskaya and Olenekskaya) produce buoyant outflows in the summer season. The surface plume buoyancy signature proves to be highly variable in time, especially in case of upwelling favourable wind events. Winds stronger than 6 m s −1 can already turn the dynamics of flows from all main freshwater channels to the wind-driven state. During the summer season, the bulk of freshwater from the Lena River stays in the eastern Laptev Sea because of location of the main Lena River freshwater channels, their large Kelvin numbers and light summer winds. Westward and northward plume excursions are wind-driven, and the model skill in simulating them depends on the available wind forcing. The main mechanism of tidal influence in the freshwater plume zone is through tidally induced mixing, except for the northern vicinity of the delta, where residual circulation may contribute to the plume eastward transport significantly.

show abstract

Tidal ice drift and ice-generated changes in the tidal dynamics/energetics on the Siberian continental shelf

Cited by 14 publications

References 13 publications

Tide‐induced vertical mixing in the Laptev Sea coastal polynya

Tide‐induced vertical mixing in the Laptev Sea coastal polynya

On the modification of tides in a seasonally ice‐covered sea

Impact of wind and tides on the Lena River freshwater plume dynamics in the summer season

Contact Info

Product

Resources

About