Die Bodenkultur - Journal for Land Management, Food and Environment

M. Lenartowicz and M. Gutry-Korycka:

Response of mountainous catchments to global climate change

Summary

The influence of global climate change on flood formation in small basins has been investigated in this study. The main goal has been the estimation of catchment response to extreme rainfall events using the rainfall-runoff model in MIKE SHE 2004. Two Carpathian river catchments located in south Poland: Biała Tarnowska/Grybów and Solinka/Terka were selected for modelling. Real and theoretical extreme rainfall data generated from archival datasets have been used to calibrate and validate the model. An important task of the study is determining projected extreme rainfall events towards the end of the 21st century, based on data from the General Circulation Model. GCM ECHAM4 rainfall projections using the sustainable SRES1b scenario have been applied to estimate predicted probable extreme rainfall totals. Modelling results indicate that the Carpathian catchments will be exposed to an increased intensity of extreme rainfall events in the second half of the 21st century. However predicted extreme peak flows will be lower for the 2046–2065 period compared to current levels, but higher for the 2081–2100 time period. Future solutions will need to be found for the problematic difference in resolution between the R–R model and the GCMs. Key words: Global climate change, ECHAM 4, GCMs, SRES scenario, MIKE SHE, rainfall-runoff modelling, simulation of flood.