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1

Assessment of climate impact on the transboundary Struma River flow in Bulgarian territory using integral indices

100%

Davidovski I. , Atanassova M. , Simeonov V.

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tom Vol. 16, nr 3

181-200

EN

The present work considers the Struma River on the Bulgarian territory using the integral method for evaluation of climatic and anthropogenic impacts on the river flow average annual water volume and maximum and minimum water flow. The level of this impact is determined by the index Ki (flow module), the index Ci for the deviation of the average annual water flow Qi from the flow norm Q0. the index Ki,max for the deviation of the maximum water flow Qmax,i from the flow norm Q0, the index Ki,min for the deviation of the minimum water flow Qmin,i from the flow norm Q0, the index Mi,max for the deviation of the maximum water flow from the maximum flow norm Qmax,0 the index Mi,min for the deviation of the minimum water flow from the minimum flow norm Qmin,0. The new approach offered includes the introduction of more specific indicators for assessment of climatic impacts on the river water flow like indices for flow module (Ki,av), for deviation of average (Ci), The use of the indices suggested makes possible to estimate the role of different climatic changes by Ki,av, Ki, in, Ki,max. Mi,min, Mi,max, Ci, hi and hi,max. This is made for the first time in assessment of climatic impacts and has been checked at Pernik and Krupnik for the period 1948-2006. The indices are integral in their nature because they reflect specific climatic caused events like abundant years, dry years, floods and draughts.

PL

Dokonano oceny wpływu zmian klimatycznych i antropogennych na średni roczny przepływ wody oraz wartość maksymalnego i minimalnego przepływu wody w rzece Struma przepływającej przez terytorium Bułgarii. Parametry te są określone przez indeks Ki (wskaźnik przepływu), wskaźnik Ci średniego odchylenia rocznego przepływu wody Qi do normy przepływu Q0, indeks Ki,max maksymalnego odchylenia przepływu wody Qmax,i do normy przepływu Q0, indeks Ki,min minimalnego odchylenia przepływu wody Qmin,i do normy przepływu Q0, wskaźnik Mi,max maksymalnego odchylenia przepływu wody do maksymalnej normy przepływu Qmax,0, indeks Mi,min minimalnego odchylenia przepływu wody do minimalnej normy przepływu Qmin,0. Nowe podejście wprowadza bardziej szczegółowe wskaźniki oceny wpływu klimatu na wody rzeki, jak wskaźniki przepływu modułu (Ki,av), odchylenie średniej (Ci), Zastosowanie sugerowanych wskaźników umożliwia ocenę roli różnych zmian klimatycznych przez Ki,av, Ki,min, Ki,max, Mi,min, Mi,max. Ci, hi i hi,max. Metoda ta została zastosowana i sprawdzona w Perniku i Krupniku dla lat 1948-2006 w celu oceny skutków zmian klimatu. Indeksy te odzwierciedlają wywołane zmianami klimatycznymi szczególne wydarzenia, takie jak: lata suche, powodzie i wiatry.

2

O usuwaniu roślinności z terenów zalewowych rzek

100%

Kubrak J. , Żelazo J. , Kozioł A. , Kubrak E. , Kiczko A.

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tom Nr 3

95--102

PL

Przedstawiono oddziaływanie roślinności na warunki przepływu wody na terenach zalewowych oraz zalecenia usuwania nadmiaru tej roślinności wyprowadzone z hydraulicznych warunków. Ich przestrzeganie powinno zapewnić obniżenie stanów wody, co jest niezwykle istotne w obrębie terenów zurbanizowanych. Dla właściwego utrzymania warunków przepływu wody w terenie zalewowym po usunięciu roślin należy przestrzegać zasad ograniczających nadmierny rozwój roślinności.

EN

The article presents influence of plants on water flow condidtions on floodplains. Hydraulic conditions indicate that the excess of vegetation should be eliminated. Implementation of such recommendation should allow water stages lowering, what is of great importance in urbanised areas. In order to maintain the water flow conditions on a floodplain, after elimination of vegetation the principles limiting the excessive vegetation growth should be respected.

3

What can we learn from the projections of changes of flow patterns? Results from Polish case studies

84%

Piniewski M. , Meresa H. K. , Romanowicz R. , Osuch M. , Szcześniak M. , Kardel I. , Okruszko T. , Mezghani A. , Kundzewicz Z. W.

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tom Vol. 65, no. 4

809--827

EN

River flow projections for two future time horizons and RCP 8.5 scenario, generated by two projects (CHASE-PL and CHIHE) in the Polish-Norwegian Research Programme, were compared. The projects employed different hydrological models over different spatial domains. The semi-distributed, process-based, SWAT model was used in the CHASE-PL project for the entire Vistula and Odra basins area, whilst the lumped, conceptual, HBV model was used in the CHIHE project for eight Polish catchments, for which the comparison study was made. Climate projections in both studies originated from the common EURO-CORDEX dataset, but they were different, e.g. due to different bias correction approaches. Increases in mean annual and seasonal flows were projected in both studies, yet the magnitudes of changes were largely different, in particular for the lowland catchments in the far future. The HBV-based increases were significantly higher in the latter case than the SWAT-based increases in all seasons except winter. Uncertainty in projections is high and creates a problem for practitioners.

4

Intense precipitation and high river flows in Europe - observations and projections

67%

Kundzewicz Z. W.

Acta Geophysica Polonica

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2005

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tom Vol. 53, nr 4

385--400

EN

Several destructive floods have occurred in the last decade in Europe, causing record high material damage. The question of detection and attribution of changes in various flood-related indices attracts increasing interest. Among the mechanisms that can impact flood risk are changes in socio-economic systems, which influence terrestrial systems, and changes in the climatic system. The atmosphere's water holding capacity (and hence potential for intense precipitation) increases with temperature and more intense precipitation has been documented in the warming world. However, a general and coherent increase in high river flows has not been detected. Results of change detection studies of daily river flow in Europe show that the overall maxima (for the 1961-2000 period) occurred more frequently in the subperiod 1981-2000 than in the subperiod 1961-1980. Regional changes in the timing of floods have been reported in many areas of Europe, with increasing incidence of late autumn and winter floods (caused by rain) and fewer spring snowmelt floods. Also, the number of ice-jam related inundations has decreased. On the other hand, intensive and long-lasting summer precipitation episodes have led to disastrous floods in Central Europe (cf. the 1997 Odra/Oder flood, the 2001 Vistula flood, and the most destructive 2002 deluge on the Labe/Elbe), and river flooding has been recently recognized as a major hazard in the region. Significant differences between future projections and the reference period, indicating the likelihood of increasing flood hazard, have been identified in both intense precipitation and high flows.