Discharge from urbanized catchments

The purpose of this study was to revision the urbanization area floods influences according mathematical models to floods simulation. It ranges through the rational formula for calculating Qmax, one-dimensional models of the relationship between intensive precipitation and discharge, the SCS method for assessment effective rainfall, the unit hydrograph UH and the instantaneous unit hydrograph IUH. Two - and three - dimensional models are then presented, along with different ways of envisaging hydrological processes in urban Systems. Support for the application of the models is offered on the basin of many examples involving different cities (Europe, Asia, North America and Poland), possibilities for finding solutions are, indicated, and limitations inherent in the modeling pointed out

The structure of natural water balance in Poland (1931-1960)

The paper presents the results of research on water balance for Poland (the work was in IHP UNESCO programme). The undertakiing of the theme was the result of hydrological cooperation within the socialist countries. The subject of the study is the structure of the water balance studied in 381 basins, in the form of Lvovitsch's differential equation, for the period 1931-1960. The structure of the equation considers a corrected value of precipitation-the so-called real precipitation. Lvovitsch's equation includes six elements of water balance: precipitation (P), surface runoff (Hp), groundwater (Hg), land evaporation (E), the so-cold mean runoff and a basin areal moisture (W). The form of the equation is as follows: P = Hp+Hg+E where H = H p+H g The groundwater runoff, however together with land evaporation determines the basin areał moisture W: W = P-Hp = E+Hg In order to characterize the structure of the water balance for Poland, the dependence of evaporation and groundwater runoff upon the areal moisture was calculated by formula: KE= E/W and evaporation coefficient and groundwater runoff coefficient by the relations: Kg = Hg/W; KE = 1-Kg = E/W All the water balance elements together with additional characteristics were presented in the form of izopleths with equal intervals. Little notice was paid to temporal distribution of each element, however, their spatial distribution was carefully examined including all the most importand regional features of Kondracki's physico-geographical regionalization. The gradient curevs of the six elements of the water balance form the basis for determining the mean water balance of major drainage basins and areas. The new estimation of the water balance can be treated only as a statical one emphasizing also the relationship between its elements and their geographical distribution. It enables verification of the natural water balance for Poland and also is a new approach in cartographic synthesis of its elements. The obtained results refer to natural conditions, however, they (may be treated as) are the foundation for estimating the future changes of the country's water resources

Floods of the Middle Vistula River in historical seizure

In the paper worked analysis and evaluate of Middle Vistula River floods during in the last millennium on the base instrumental and proxy data. Information on floods in the pre-instrumental period is derived from documentary sources. In order to extend the flood - related records, recourse must be made to historical hydrology main river - Vistula River. Sources of flood -related information (traces on the memory great river water levels) are examined and the particularities of the situation, driven by the history of Poland, were explained. Changing characteristics of floods of different generation mechanisms (intensity of precipitatation, snowmelt or ice-jam discussed)

Urszula Soczyńska

Urszula Soczyńska, born Czaplińska, graduated in water building engineering at the Warsaw Technical University in 1957. In 1956 she began didactic course on hydraulics and fluid mechanics at the Warsaw Technical University and then in 1960 she moved to the National Institute of Hydrology and Meteorology where she organized the Laboratory of Hydrologic Prognostic Methodology. During 50 years of scientific and didactic work she dedicated herself mostly to the issues of forecasting, especially of floods and icings of rivers. She was promoted a doctor on the basis of her dissertation The method of forecasting of the river freshets in the mountainous regions of Poland basing on specific unit hydrograph waves characteristics under the guidance of professor Julian Lambor. In 1975 she was promoted a docent at the Institute of Meteorology and Water Adrninistration where she ran the Department of Dynamic Hydrology. The collected research findings served as a base for her habilitation dissertation Methodological bases of the regional model of basin in the Polish conditions which was conducted in 1977 at the Faculty of Geography and Regional Studies of the Warsaw University. In 1978- 2001 professor Urszula Soczyńska was bound with the University of Warsaw, first as a docent and later as a professor at the Department of Hydrology within the Faculty of Geography and Regional Studies. An outstanding hydrologist, an expert in mathematic modelling, for 10 years she ran the Department of Hydrology where she introduced the modern methods of prediction of reception basins outflow on the basis of precipitation transformation with the specific recurrence probability. In 1984- 1990 she was the Director of the Institute of Physico-geographical Sciences. In 1990- 1993 she was the Dean of the Faculty of Geography and Regional Studies, implementing creative organizational, didactic, and staff system changes. She was the author of over a hundred hydrologic papers acknowledged in Poland and abroad and an organizer of the international cooperation with the European countries within the framework of UNESCO-IHP FRIEND in the field of hydrologic research upon the experimental basins used to predict river floods and low flows. Her methodological and applied papers had good theoretical bases and were grounded on the extensive empirical material. She was an unquestioned expert in Polish and European hydrology and her works and methodological bases are stili valid

Snowmelt alimentation processes of the unit basin area

The paper presents the physical background of the vertical water transformation modeling in the unit quasi-homogeneous forest area with in the winter season. The model structure includes all main processes operating in precipitation (rain and snow) and snow cover interception on forest canopy and forest ground. Special attention has been paid on the kohesion, accumulation, heat and moisture flux processes, evaporation and sublimation from snow cover, change in the water phase and water percolation through snow on the canopy and ground. Basic processes were considered in terms of quasi-homogeneous unit forest area. Each component of the model was described by the mathematical-physics equations. Parameters of the model are the physical characteristics of the plant canopy, ground and air conditions. The concept of the model should be used to simulation of the net precipitation and snowmelt feeding of the unit forest area

Regional conditioning of the rivers response to heavy raifall in actual conditions and in the perspective of global warming

The global warming is important factor influencing changes in water circulation. Global Circulation Models (GCMs) developed in the last decades have enabled assessment of global warming effect. The goal of this study is to apply the mathematical rainfall - runoff model to evaluate the rate and direction of changes in flood formation resulting from climate changes using historical data and generated by ECHAM4 GCM in 5 selected basins in Poland. The study confirm that main factors controlling flood formation in present are precipitation intensity, topography and land cover. According to modeling results in the perspective of 80 - 90 years only the floods in Carpathian region will exceed those observed in the past years. In the Polish Lowlands maximum precipitation totals of p= 1% will be from 20 to even 50% lower than in the last decades, thus river runoff will decrease

Reconstruction of the Vistula River extreme fl oods passage through the City of Warsaw in natural river conditions

Geomorphology of the Vistula River Valley in Warsaw has been presented, as well as history of flood protective dikes and channel regulation works. From historical sources we have the description of catastrophic flood of 1635. The level of the flood of 1844 has been preserved in the form of high water mark. Using two dimensional hydrodynamic model CCHE2D the simulation of thousand years recurrence flood has been performed. It has been compared the result of the calculations with historical chronic and high water mark. It has been calculated the pattern of flood water flow over Praga district terrace, showing also the possibility of flood flow directly to Narew river through the relive channels leading by a terrain depressions of today's Zeranski Canal and Bródnowski Canal