Investigation of trend in hydrological time series of the Evinos River basin

Abstract

This paper presents an investigation of trend in historic hydrological time series of areal annual precipitation on and mean annual runoff from the basin of the Evinos River in western Greece. Using different tests for randomness, a statistically significant long lasting decreasing trend was found in the precipitation record, whereas an also significant fluctuating “local” trend was detected in the runoff record. Further, it is shown that the effects of precipitation change on mean annual runoff can be quantified through a magnification factor.