Second Assessment of Climate Change for the Baltic Sea Basin

This chapter compiles and assesses information on run-off and discharge from rivers within the Baltic Sea drainage basin. Some information is also available on ice duration on inland waterways. Although decadal and regional variability is large, no significant long-term change has been detected in total river run-off to the Baltic Sea over the past 500 years. A change in the timing of the spring flood has been observed due to changes in the timing of snowmelt. Change in temperature seems to explain change in run-off better than does precipitation. Later start dates for ice formation on waterways, and earlier ice break-up dates have resulted in shorter periods of ice cover.</div

Application of Artificial Neural Network into the Water Level Modeling and Forecast

The dangerous sea and river water level increase does not only destroy the human lives, but also generate the severe flooding in coastal areas. The rapidly changes in the direction and velocity of wind and associated with them sea level changes could be the severe threat for navigation, especially on the fairways of small fishery harbors located in the river mouth. There is the area of activity of two external forcing: storm surges and flood wave. The aim of the work was the description of an application of Artificial Neural Network (ANN) methodology into the water level forecast in the case study field in Swibno harbor located is located at 938.7 km of the Wisla River and at a distance of about 3 km up the mouth (Gulf of Gdansk ‐ Baltic Sea)

Sea Ice Services in the Baltic Sea

The Baltic winter navigation depended always very much on the ice conditions in the sea. The sea ice occurs different in form and amount, depending on the sea area and the winter season. As the maritime traffic on the Baltic Sea constitutes a substantial amount in the whole of the Baltic countries transport, Sea Ice Services (SISs) have come into being. They constituted the Baltic Sea Ice Meeting (BSIM) – a body, which assembles the parties, which are interested in warnings against bad ice conditions, and in protection of navigation in ice in the Baltic Sea. An indispensable co-operator to this body was always the company “Baltic Icebreakers”. To-day within the BSIM operate by the SISs of Denmark, Sweden, Finland, Russia, Estonia, Latvia, Lithuania, Poland and Germany, Netherlands, Norway and the Baltic Icebreakers. The main statutory duties of the SISs is the acquisition, processing and dissemination of actual information on sea ice conditions and on obstructions to navigation due to sea ice. This is done by maintaining observing posts along the coast of those countries, in their ports and approaches to them, by gathering information from ships, from ice beakers, if possible – from reconnaissance flights or satellite images. Routine products of SISs are the ice reports, ice bulletins, ice charts, forecasts and warnings and other information broadcast by mass media, e.g. radio, internet, Navtex and on the national and Baltic SISs’ web sites etc

Powodzie i susze na dolnej Wiśle

The study analyses floods and droughts on the lower Vistula based on the data (water levels and flow rates) recorded in stations of the Institute of Meteorology and Water Management – National Research Institute (IMGW-PIB) in Warsaw, Kępa Polska, Toruń and Tczew. It also includes the causes of flooding and drought in the lower Vistula with the hydrological characteristics from the years 1951–2010. The variability in maximum and minimum annual and monthly flow rates has been analysed for the aforementioned period as well. In addition, the authors have analysed changes in the shape of the flood wave after passing through the reservoir and cascade in Włocławek based on the hydrograph of May and June 2010. It has been found that the flood wave is flattened and extended. This phenomenon is favourable from the point of view of flood actions.W pracy przeanalizowano powodzie i susze na dolnej Wiśle na podstawie danych (stany wody i przepływy) zanotowanych na stacjach IMGW-PIB Warszawa, Kępa Polska, Toruń i Tczew. Przedstawiono przyczyny powstawania powodzi i suszy na dolnej Wiśle, wraz z charakterystyką hydrologiczną z lat 1951–2010. Przeanalizowano również dla tego okresu zmienność maksymalnych i minimalnych przepływów rocznych i miesięcznych. Ponadto przeprowadzono badanie zmiany kształtu fali wezbraniowej po przejściu przez zbiornik i stopień we Włocławku, na podstawie hydrogramów z maja i czerwca 2010 roku. Stwierdzono, że fala wezbraniowa wypłaszcza się i wydłuża. Jest to zjawisko korzystne z punktu widzenia prowadzenia akcji przeciwpowodziowej