A calculation of the intra-annual dynamics of the Ob Bay hydrophysical regime with high spatial resolution

This study is based on numerical experiments data analysis performed using the Delft3D model configuration adapted for Ob Bay region. The work discusses the results of numerical simulation of the intra-annual variability of individual parameters of the thermo-, hydrodynamic and ice regime of investigated area on a computational grid with a spatial resolution of 50–100 m horizontally and 1–2 m depthly, and using the non-hydrostatic mode. The selection of control parameters values made possible to bring this configuration of the model to a stable mode of function and most fully adapt it to the conditions of high (polar) latitudes.

The performed numerical experiments showed an adequate reproduction of the hydrophysical and ice regime of Ob Bay during the calculation period. The data obtained in calculations process were compared with the available in-situ observations made in Ob Bay. To demonstrate the operation quality of the model’s adaptable configuration, based on the results of modeling the current velocity, fluctuations in sea level and ice cover thickness, an estimate of the calculation errors was performed. A comparative analysis of the evolution of selected parameters obtained as a result of numerical experiments with observational data demonstrated the positive capabilities of the Delft3D model complex. The maximum values of the calculation errors mainly depend on the quality of the input data. Thus, the Delft3D model complex adapted to Ob Bay area can be used to successfully resolve some applied hydrometeorological, morphological, and environmental problems in the development and operation of this Arctic region.

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