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Seasonal precipitation and temperature reconstructions based on tree-ring chronologies were implemented into the hydrological modelling system PREVAH (PREcipitation-Runoff-EVApotranspiration-HRU model) to model past annual and monthly hydrological cycles back to 500 B.C. Two Swiss catchments were selected for which the hydrological modelling System PREVAH has been successfully calibrated: The Murg stream in the canton of Thurgau and the Dischmabach stream in the canton of Graubuenden. Unfortunately, due to an internal model error, false volume corrections were computed by PREVAH. Therefore, no statistical tests regarding absolute values were conducted. However, correlation coefficients were calculated and for now, this first attempt does detect paleohydroclimatic trends. Possible error sources are also examined and discussed thus the results depend on the tree-ring quality.

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Eric Gasser holds a Master of Science in Physical Geography degree from the University of Zurich (UZH) minoring in Earth Science at the Swiss Federal Institue of Technology in Zurich (ETH). His interests and skills are in geomorphology, geochronology, glaciology, dendrochronology, hydrology, paleoclimatology and sedimentology.

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