Halina Kowalewska-Kalkowska

Hydrological forecasting in the Oder Estuary using a three-dimensional hydrodynamic model

A three-dimensional operational hydrodynamic model, developed at the Institute of Oceanography, University of Gdańsk was used to forecast hydrological conditions in the Oder Estuary. The model was based on the coastal ocean circulation model known as the Princeton Ocean Model (POM). Because of wind-driven water backup in the Oder mouth, a simplified operational model of river discharge, based on water budget in a stream channel, was developed. Linking these two models into a single system made it possible to forecast water levels, currents, water temperature, and salinity in the estuary. A good fit between the observed and computed data allowed to consider the model as a reliable environmental tool. Obtaining a hydrological forecast via a quick website access gives potential users an opportunity to predict the day-by-day course of processes that may affect different areas of human life and activities, e.g., navigation, port operations, flood protection of coastal areas; the predictions may also be used in studies of coastal processes in the estuary.

Water level fluctuations in the Odra River mouth area in relation to passages of deep low-pressure systems

Water level fluctuations in the Odra River mouth area in relation to passages of deep low-pressure systems The Odra River mouth area is affected by storm surges caused by passages of deep low-pressure systems over the Baltic Sea. The surges are the result of wind action and changes in atmospheric pressure at the sea surface. The two effects may be additive, in which both factors increase or decrease the sea level on the coast, or they may be non-additive, where one factor increases the sea level and the other decreases it. This paper discusses the role of the wind field and changes in atmospheric pressure in the duration and extent of storm surges in the Odra River mouth area.

Modeling water exchange in the Oder River mouth area

Modeling water exchange in the Oder River mouth area A three-dimensional operational hydrodynamic model of the Baltic Sea (M3D_UG) developed based on the Princeton Ocean Model (POM) was applied to model water exchange in the Oder River mouth area. Due to wind-driven back flow in the Oder mouth, a simplified operational model of river discharge was also developed based on the water budget in a stream channel. Linking the Oder discharge and Baltic Sea models into a single system allowed simulating hydrodynamic conditions in the Szczecin Lagoon and the Pomeranian Bay. Since the model adequately approximates hydrodynamic variability, it is a reliable tool for modeling water exchange in the Oder River mouth area and for assessing Oder water spread in the Baltic Sea.

Changes in hydrographic conditions associated with 2005–2007 storm surges in the Odra mouth — a numerical study

A pre-operational hydrodynamic model of the Baltic Sea (M3D_UG), developed at the Institute of Oceanography, University of Gdansk was used to describe changes in hydrodynamic conditions in the Odra mouth (the southern Baltic Sea) during storm surges that occurred in the years 2005-2007. The model was based on the coastal ocean circulation model known as the Princeton Ocean Model (POM). Because of wind-driven water backflow in the Odra mouth, a simplified operational model of river discharge, based on water budget in a stream channel, was developed. Linking these two models into a single system made it possible to forecast water levels as well as water physical features in the Szczecin Lagoon and the Pomeranian Bay. Evaluation of the modelpsilas performance for two simulations that were carried out showed a good fit between the observed and computed data. The model correctly reflected events involving high-amplitude and rapid water level fluctuations as well as fast changes of physical properties of the water; it also generated relatively good flow simulations.