Badania Fizjograficzne, Seria A, Tom 68, 2017

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https://repozytorium.amu.edu.pl/handle/10593/23636

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Browsing Badania Fizjograficzne, Seria A, Tom 68, 2017 by Author "Wrzesiński, Dariusz"

Now showing 1 - 4 of 4
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    Identyfikacja cech reżimu odpływu rzek w Polsce na różnych poziomach grupowania
    (Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2017) Wrzesiński, Dariusz
    The paper presents the characteristics of the river regime types in Poland which were obtained by applying the unsupervised approach to the regime based on the results of clustering rivers with respect to the values of the 12 monthly flow coefficients in the average annual cycle. In the paper were used daily flow values from the period 1971–2010 for 516 gauges located on 280 Polish rivers.On three clustering levels, 5, 9 and 12 varieties of river runoff regimes were identified and detailed. The paper also presents the spatial distribution of rivers that represent these variants.
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    Przestrzenne i czasowe zróżnicowanie amplitud stanów wody jezior w Polsce w latach 1981–2015
    (Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2017) Plewa, Katarzyna; Wrzesiński, Dariusz; Baczyńska, Alicja
    The objective of the paper is the determination of the value and spatial variability of monthly and annual amplitudes of water stages in Polish lakes. The study applied daily values of water stages of 74 lakes located in Polish lakelands. Mean, maximum, and extreme amplitudes of water stages were calculated for each month and year in the period 1981–2015. The study revealed similar spatial distribution of isoamplitudes. Considerably higher amplitudes, however, both monthly and annual, occurred in coastal lakes and in the central part of the lakeland belt from Gopło to Druzno.
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    Typologia reżimu odpływu rzek w Polsce w podejściu nadzorowanym i nienadzorowanym
    (Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2017) Wrzesiński, Dariusz
    The paper presents a typology of the river regime in Poland obtained with the application of a supervised approach, i.e. a classic typology according to the assumptions of Dynowska with a regime typology obtained in an unsupervised approach by means of hierarchical grouping. In both cases, the explanatory variables were monthly flow coefficients – respectively: only from spring and summer months, with predefined threshold values, or 12-month flow coefficients. The paper applied daily flow values from the period 1971– 2010 for 516 gauges located on 280 Polish rivers. In both approaches, five types of regime were designated, including rivers characterised by a similar distribution and range of monthly runoff values in an average annual cycle. The designated groups, however, differ in abundance, which affects the image of spatial distribution of rivers representing the types of regime identified. The analysis shows that irrespective of the adopted method of designation, two types of regime, namely nival poorly developed and pluvio-nival are evidently characterised by different patterns of flow variability in an average annual cycle, and concern similar groups of rivers.
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    Wpływ Oscylacji Północnoatlantyckiej na zmiany stabilności reżimu stanów wody jezior w Polsce
    (Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2017) Plewa, Katarzyna; Wrzesiński, Dariusz
    The paper presents results of research on the stability of water stage regime of Polish lakes in different phases of the North Atlantic Oscillation. The stability of the regime was defined as the degree of regularity of occurrence of a particular phase of the hydrological regime, i.e. high and low water stages. The determination of the stability of water stage regime in lakes applied the stability coefficient. The analysis covered data concerning mean monthly values of water stages from 1976–2010 for 34 lakes located in Polish lakelands. According to the study, the effect of changes in the North Atlantic Oscillation on water stages in lakes is variable in time and space. In the positive NAO phase, maximums on lakes occur earlier than on average – in winter and spring, and in the negative phase - later. Minimums change in a lower range, particularly in the positive NAO phase. In the negative phase, on the majority of lakes, the term of appearance of Imin was later than on average. The term of occurrence of minimums is considerably variable, particularly in the positive phase, and in the negative phase it is usually later, and occurs in autumn.