Climate Variability and Change—Hydrological Impacts (Proceedings of the Fifth FRIEND World Conference held at Havana, Cuba, November 2006), IAHS Publ. 308, 2006, 520–525.

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Long-term trends and runoff fluctuations of European rivers

PAVLA PEKAROVA¹, Pavol MIKLANEK¹ & Jan PEKAR²

1 Institute of Hydrology, Slovak Academy of Sciences, Racianska 75, 831 02 Bratislava 3, Slovak Republic

pekarova@uh.savba.sk

2 Department of Applied Mathematics and Statistics, Faculty of Mathematics, Physics and Informatics, Comenius University, 842 48 Bratislava, Slovak Republic

Abstract In this paper the occurrence of dry and wet periods for 18 major European rivers during the period 1850–1997 is analysed. Annual discharge series were standardized for three regions: West/Central Europe, East Europe and North Europe, and for the whole of Europe. The statistical analysis of these series did not confirm any long-term increase or decrease in discharge during the last 150 years. Dry cycles of about 13.5 years and 28–29 years were identified. In East Europe the occurrence of the wet and dry cycles are shifted compared to North and West/Central Europe by a few years. Similar periods have been reported in other world rivers (Amazon, Congo) as well as in the Southern Oscillation, North Atlantic Oscillation and Pacific Decadal Oscillation phenomena. The time shift of cycles in different regions is the regularity related to general oceanic and atmospheric circulation.

Key words long-term trends; discharge; Europe; natural fluctuation; wet and dry cycles

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