Variability of River Runoff in Poland and Its Connection to Solar Variability

Wrzesiński, Dariusz; Sobkowiak, Leszek; Mares, Ileana; Dobrică, Venera; Mares, Constantin

doi:10.3390/atmos14071184

Cited by 3 publications

(4 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The elimination of redundancy [56] in synergistic multiple linkages gives added value to nonlinear statistical physics for information theory in coevolutionary systems. Also, global wavelet coherence analysis with different lags between the predictand (discharge) and the predictor (SSN) can provide significant useful information, as recently obtained in the paper [57].…”

Section: Amplitudementioning

confidence: 70%

Discriminant Analysis of the Solar Input on the Danube’s Discharge in the Lower Basin

Mares

Dobrica

et al. 2023

Atmosphere

Self Cite

View full text Add to dashboard Cite

This paper presents the extent to which the combination of extra-atmospheric and hydroclimatic factors can be deciphered to record their contribution to the evolution and forecasting of the Danube discharge (Q) in the lower basin. A combination of methods such as wavelet filtering and deep learning (DL) constitutes the basic method for discriminating the external factors (solar activity through Wolf numbers) that significantly contribute to the evolution and prediction of the lower Danube discharge. An ensemble of some of the most important factors, namely, those representing the atmospheric components, i.e., the Greenland-Balkan Oscillation Index (GBOI) and the North Atlantic Oscillation Index (NAOI); the hydroclimatic indicator, the Palmer Hydrological Drought Index (PHDI); and the extra-atmospheric factor, constitutes the set of predictors by means of which the predictand, Q, in the summer season, is estimated. The external factor has to be discriminated in the Schwabe and Hale spectra to make its convolutional contribution to the Q estimation in the lower Danube basin. An interesting finding is that adding two solar predictors (associated with the Schwabe and Hale cycles) to the terrestrial ones give a better estimation of the Danube discharge in summer, compared to using only terrestrial predictors. Based on the Nash–Sutcliffe (NS) index, a measure of performance given by the extreme learning machine (ELM), it is shown that, in association with certain terrestrial predictors, the contribution of the Hale cycle is more significant than the contribution of the Schwabe cycle to the estimation of the Danube discharge in the lower basin.

show abstract

Section: Amplitudementioning

confidence: 70%

Discriminant Analysis of the Solar Input on the Danube’s Discharge in the Lower Basin

Mares

Dobrica

et al. 2023

Atmosphere

Self Cite

View full text Add to dashboard Cite

show abstract

“…Spadki zasobów wodnych są tam szczególnie niebezpieczne ze względu na istnienie ich deficytów już teraz utrudniających wegetację roślinną (Kożuchowski 2013). Badane były również zmiany odpływów najważniejszych rzek Polski: Wisły, Odry i Warty (Wrzesiński i in. 2023), Narwi (Malinowski, Skoczko 2018) i rzek Przymorza (Świątek, Walczakiewicz 2022) oraz w ogólniejszym ujęciu -na terenie całej Polski (Wrzesiński 2009;Piniewski i in.…”

Section: Wprowadzenieunclassified

“…Największe spadki przepływów dotyczyły wiosny. Istotne trendy malejące przepływów rzecznych odnotowano również w Wiśle w Tczewie w latach 1901-2020 (Wrzesiński i in. 2023).…”

Section: Dyskusjaunclassified

Zmiany odpływów jednostkowych w nizinnej części Polski w latach 1961–2021

2024

AGL

View full text Add to dashboard Cite

Changes in specific discharge in the lowland part of Poland in the years 1961-2021 MAŁGORZATA ŚWIĄTEK 1 Zarys treści. Przedmiot badań stanowiła analiza zmian zasobów wodnych nizinnej części Polski na podstawie wielkości odpływów jednostkowych z 39 zlewni zlokalizowanych na pobrzeżach, pojezierzach i nizinach w latach hydrologicznych 1961--2021. Analizy przeprowadzono w oparciu o trendy zmian średnich rocznych oraz miesięcznych odpływów z poszczególnych zlewni z uwzględnieniem ich istotności statystycznej. Wykonano również grupowanie zlewni metodą Warda pod względem tempa obserwowanych zmian (współczynników kierunkowych trendu) odpływów jednostkowych w poszczególnych miesiącach.Niemalże w połowie badanych zlewni wykazano istotny spadek średnich rocznych odpływów jednostkowych. W żadnej nie odnotowano istotnego statystycznie trendu wzrostowego tego parametru. W większości zlewni odnotowano spadki odpływów w miesiącach wiosennych (kwiecień i maj), a w czterech wzrosty w miesiącach zimowych (styczeń i luty). Największe ubytki zasobów wodnych, mierzonych wielkością odpływu jednostkowego, cechowały zlewnie z terenów równinnych o małej naturalnej retencyjności położonych w obrębie nizin.

show abstract

“…The relatively recent methods of investigation bring more information about the solar impact, as well as the response of the most important climatic factors that have an influence on the evolution of the discharge of the world's large rivers [20,21,24,27,32,39,[55][56][57][58][59][60][61][62][63]. These investigations are based on the application of robust techniques for systems with non-linear and non-stationary evolution, as well as the detection of the appropriate signal with the spatio-temporal scale of interest.…”

Section: Introductionmentioning

confidence: 99%

The Combined Effect of Atmospheric and Solar Activity Forcings on the Hydroclimate in Southeastern Europe

Mares,

Dobrica,

Demetrescu

et al. 2023

Atmosphere

Self Cite

View full text Add to dashboard Cite

The purpose of this study was to analyze the influence of solar activity described by the sunspot number (SSN) on certain terrestrial variables that might impact the Southeastern European climate at different spatio-temporal scales (the North Atlantic Oscillation Index, NAOI, and the Greenland–Balkan Oscillation Index, GBOI—on a large scale; the Palmer Hydrological Drought Index, PHDI—on a regional scale; the Danube discharge at the Orsova (lower basin), Q, representative of the Southeastern European climate—on a local scale). The investigations were carried out for the 20th century using the annual and seasonal averages. To find the connections between terrestrial (atmospheric and hydrological) parameters and SSN, the wavelet coherence were used both globally and in the time–frequency domain. The analyses were carried out for the time series and considered simultaneously (in the same year or season), as well as with lags from 1 to 5 years between the analyzed variables. For the annual values, the type of correlation (linear/non-linear) was also tested using elements from information theory. The results clearly revealed non-linear links between the SSN and the terrestrial variables, even for the annual average values. By applying the wavelet transform to test the solar influence on the terrestrial variables, it was shown that the connections depend on both the terrestrial variable, as well as on the considered lags. Since, in the present study, they were analyzed using wavelet coherence, but only the cases in which the coherence was significant for almost the entire analyzed time interval (1901–2000) and the terrestrial variables were in phase or antiphase with the SSN were considered. Relatively few results had a high level of significance. The analysis of seasonal averages revealed significant information, in addition to the analysis of annual averages. Thus, for the climatic indices, the GBOI and NAOI, a significant coherence (>95%) with the solar activity, associated with the 22-year (Hale) solar cycle, was found for the autumn season for lag = 0 and 1 year. The Hale solar cycle, in the case of the PHDI, was present in the annual and summer season averages, more clearly at lag = 0. For the Danube discharge at Orsova, the most significant SSN signature (~95%) was observed at periods of 33 years (Brüuckner cycle) in the autumn season for lags from 0 to 3 years. An analysis of the redundancy–synergy index was also carried out on the combination of the terrestrial variables with the solar variable in order to find the best synergistic combination for estimating the Danube discharge in the lower basin. The results differed depending on the timescale and the solar activity. For the average annual values, the most significant synergistic index was obtained for the combination of the GBOI, PHDI, and SSN, considered 3 years before Q.

show abstract

Variability of River Runoff in Poland and Its Connection to Solar Variability

Cited by 3 publications

References 44 publications

Discriminant Analysis of the Solar Input on the Danube’s Discharge in the Lower Basin

Discriminant Analysis of the Solar Input on the Danube’s Discharge in the Lower Basin

Zmiany odpływów jednostkowych w nizinnej części Polski w latach 1961–2021

The Combined Effect of Atmospheric and Solar Activity Forcings on the Hydroclimate in Southeastern Europe

Contact Info

Product

Resources

About