reference period

Comparison of hydrological characteristics of M-day discharges of the reference period 1981–2010 and the considered reference period 1991–2020

According to the Czech technical standard ČSN 75 1400 Hydrological data of surface waters, M-day discharges are a part of the Basic hydrological data [1]. The values of M-day discharges in water gauging stations are derived from time series of observed mean daily discharges over a defined reference period. The reference period 1981–2010 is currently used for design purposes [2]. With the end of the second decade of the 21st century, a change in the reference period for 1991–2020 is being considered. In the past, the Czech Hydrometeorological Institute (CHMI) provided hydrological data for the reference periods 1931–1940, 1931–1960, and 1931–1980.