Jadwiga Rotnicka

Abstract

Will the hydrological regime of rivers be transformed as a result of global climatic :hange, assuming physico-geographical properties of catchments to be permanent? An answer to this question was sought by way of comparison of the behaviour patterns of a river (its discharge structure in the normal yearly cycle) in real conditions defined on the basis of an observation series from the years 1961-1990 (scenario 0), and in the conditions of the assumed climatic change (GFDL and GISS scenarios). The assessment of changes in the regine was made in quantitative and qualitative terms.The Rega, the Utrata and the Soła, three rivers, whose catchments lie in different physico-geographical regions of Poland were chosen for the analysis, in order to gain an insight iito the direction and intensity of changes at a regional scale also.The -esults obtained corroborate the impact of global climatic change on the rivers, both at the rmso-scale of Poland and the regional scale. The total annual discharge may change significantly, either by going up, according to the GISS scenario, or going down, according to the G?DL scenario. The transformation of the discharge rhythm may manifest itself in a shift ii the stages of discharge while seasonality is maintained, and in a change in its magnitude in particular seasons (e.g., the lowering of the level of base flows and their lengthering, mainly in mountain and lowland streams, as well as restricted and greatly reduced neltwater floods).

Keywords: hydrological regime of rivers, effect of global climatic change

Małgorzata Gutry-Korycka, Faculty of Geography and Regional Studies, University of Warsaw Krakowskie Przedmieście 30, 00-927 Warszawa, Poland
Jadwiga Rotnicka, Institute of Physical Geography, Adam Mickiewicz University ul. Fredry 10, 60-701 Poznań, Poland