An opportunity of application of excess factor in hydrology

Abstract

In last few years in hydrology an interest to excess factor has appeared as a reaction to unsuccessful attempts to simulate and predict evolving hydrological processes, which attributive property is statistical instability. The article shows, that the latter has a place at strong relative multiplicative noises of probabilistic stochastic model of a river flow formation, phenomenological display of which are "the thick tails" and polymodality, for which the excess factor "answers", by being ignored by a modern hydrology in connection to the large error of its calculation because of insufficient duration of lines of observation over a flow. However, it is found out, that the duration of observation of several decades practically stabilizes variability of the excess factor, the error of which definition appears commensurable with an error of other calculated characteristics used in engineering hydrology

Geographic Pattern as a Determinant Factor of Interlinking Climatic and Hydrological Components of the Natural Resources

“…The table 1 shows that all three temperature zones have series with both positive and negative values of ε. However, due to the low accuracy of ε calculation (for short series), it is reasonable to focus on its average (for all series and for each zone) values, which are close to zero in the northern zone and for the range of our interest are 1.6-7 °C -0.25 (the material on the accuracy of the coefficient of kurtosis can be found in the source [10]). This indicates that peaked distributions dominate objectively in this range, although there are many distributions with small negative values of ε, i.e., with flattened or bimodal vertex.…”

“…Needless to say that such eliminating is done for objective reasons -insufficient time length of the runoff observation series, which brings significant errors in the estimates of Cs and ε. However, it can be demonstrated [10] that the numerical evaluations of Cs and ε become steady if the length is 40-50 years (for Cs) and 60-70 years (for ε). Fig.…”