Abstract
Trends in hydro-climatic long-term data series in the upper course of the Hron River basin from 1931 to 2010 was realized by simple and double mass curves method of precipitation and runoff data, linear regression method of temperature and analysis of snow cover data. The evaluation of seasonality, frequency and extremity of flooding was supplemented.
The Mann-Kendall seasonal test was taken as a basic statistical test of trends. The increase of runoff regime was observed in the period between the 2nd half of the sixties and the 1st half of the eighties.
Since this period the runoff is decreasing. The greatest changes were confirmed in evaluation of temperature with the increase at all climatic stations.
The decreasing trend of snow cover is noticeable. Changes in amount of precipitation were not documented.
The flooding was bigger in the period 1931–1980 with the most flood year 1945. The most extreme flood was in 1974.