scholarly journals ON THE POSSIBILITY OF LONG-TERM FORECASTING OF SEASONAL HYDROMETEOROLOGICAL PHENOMENA

2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Svetlana Morozova ◽  
Mariya Alimpieva

In present paper the expanding application possibility of physical-statistical methods in long-term forecast are viewed.A nonparametric discriminate analyzing model has been constructed on the South-East of EPR (European part ofRussia). The model is based on consideration of asynchronous bonds between the condition of circulating systems of theAtlantic-Eurasian hemisphere sector and the period of seasonal hydrotermeological events onset on South-East of ЕPR.This model allows distinguishing three cluster areas which associate with three phases of predicted event; commonly,only two cluster areas are distinguished. We would like to present results of predictions testing of training and controlsets. The conclusion of our model region appliance effectiveness is also represented in paper.

2017 ◽  
pp. 156-163
Author(s):  
Zh.R. Shakirzanova

Introduction. Modern hydrology of the Hadzhibeysky estuary is due to natural and anthropogenic factors and characterized by their intense economic use. Since the beginning of the last century, there was an intense discharge of municipal waters from Odessa (biological treatment plant "North"). This led to a significant increase in the levels of water in the estuary, which threatened to destroy the dam that separates the estuary from the sea, with the possible flooding of residential areas and enterprises of the Peresip area, as well as the road, on the dam, especially in disastrously high water years. Purpose. The purpose problems – are estimation of filling the closed estuaries-reservoirs in north-west area of the Black sea and long–term forecasting of their condition during the spring period of year. The first task – an analysis of conditions of the Hadzhibeysky estuary in the presence of an exceptional spring flood and rain floods of exceedance probability (P = 1%). The second task – is to develop a methodology for the long-term forecasting of filling of the Hadzhibeysky estuary during the spring flood, which is the most abundant phase in the hydrological regime into the territory. Results. For the first time, the possibility of assessing the filling degree surface water from melting snow and rainfall when the estimated probability of exceeding P=1% in the closed estuaries-reservoirs of the Black Sea areas. The method of the long-term forecast of surface water during the spring period for the closed estuaries was substantiated. Typification of spring floods in accordance with their water content according to the model – discriminant function DF, which takes account of the complex of factors having an influence upon conditions of spring flood formation. Setting the probability of occurrence of the forecasting flow layers in the long-term period are implemented. Conclusion. This method allows risk assessment for sustainable land – and water use planning within the Black Sea estuaries. The method of the long-term forecast was realized by the author in operational work at the Hydrometeorological Center of the Black and Azov Seas.


2021 ◽  
Vol 38 ◽  
pp. 00122
Author(s):  
Tatyana Sokolova

The article presents the results of long-term research of ravine oak forests of the Rostov region.The term ‘bayrack’ (ravine) forest is associated with the growing of forests of this type on the slopes of ravines in the forest-steppe zone. The conducted ecological and floral classification showed a high syntaxonomic diversity of ravine oak forests of the region. Forest communities are represented by 6 associations: Scorzonero ensifoliae–Quercetum Sokolova ex Semenishchenkov 2020; Vicio pisiformis–Quercetum roboris Semenishchenkov 2012; Pyro pyrastri– Quercetum roboris Poluyanov 2012; Chamaecytiso ruthenici–Quercetum roboris Poluyanov 2012; Fritillario ruthenici-Quercetum roboris Onyschenko, Dyakova et Karpenko ex Goncharenko in Goncharenko et al. 2020, Melico pictae-Ulmetum minoris ass. nov. prov. from 2 classes: Carpino–Fagetea, Quercetea pubescentis and 2 unions: Aceri campestris-Quercion roboris and Scutellario altissimae-Quercion roboris. There are 67 rare plant species listed in the Red Books of the Rostov [1], Volgograd [2] and Voronezh [3] regions in the communities of these associations. Oak forests in the south of the European part of Russia significantly increase the biological diversity not only of the Don region, but also of the entire steppe zone of the country.


2021 ◽  
Vol 3 ◽  
pp. 99-114
Author(s):  
G.I. Anzhina ◽  
◽  
A.N Vrazhkin ◽  

There is a similarity in dynamics and a quantitative difference in the ice cover regime in four consecutive 30-year periods: 1961–1990, 1971–2000, 1981–2010, 1991–2020 are noted. The greatest differences are observed in the regime characteristics of the first and the last periods. The absolute maximum or minimum recorded in at least one of the months from January to May determines the nature of the ice cover of the entire ice season. The sensitivity of the predictive physical-statistical model to the replacement of climatic norms has been investigated. Estimates of the quality of forecasts of the average monthly ice cover are obtained. Keywords: base period, long-term forecast, physical and statistical model, ice cover, climate characteristics, typification, forecast skill scores


Vaccines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 728
Author(s):  
Tareq Hussein ◽  
Mahmoud H. Hammad ◽  
Pak Lun Fung ◽  
Marwan Al-Kloub ◽  
Issam Odeh ◽  
...  

In this study, we proposed three simple approaches to forecast COVID-19 reported cases in a Middle Eastern society (Jordan). The first approach was a short-term forecast (STF) model based on a linear forecast model using the previous days as a learning data-base for forecasting. The second approach was a long-term forecast (LTF) model based on a mathematical formula that best described the current pandemic situation in Jordan. Both approaches can be seen as complementary: the STF can cope with sudden daily changes in the pandemic whereas the LTF can be utilized to predict the upcoming waves’ occurrence and strength. As such, the third approach was a hybrid forecast (HF) model merging both the STF and the LTF models. The HF was shown to be an efficient forecast model with excellent accuracy. It is evident that the decision to enforce the curfew at an early stage followed by the planned lockdown has been effective in eliminating a serious wave in April 2020. Vaccination has been effective in combating COVID-19 by reducing infection rates. Based on the forecasting results, there is some possibility that Jordan may face a third wave of the pandemic during the Summer of 2021.


2020 ◽  
Vol 29 (1) ◽  
pp. 166-175
Author(s):  
Valeriia A. Ovcharuk ◽  
Mariia E. Daus ◽  
Natalia S. Kichuk ◽  
Mariia I. Myroshnychenko ◽  
Yurii V. Daus

The analysis of current scientific work on the use of statistical methods in hydrochemical research has shown that this approach is sufficiently substantial, both in Ukraine and abroad. The purpose of this work is to determine the main statistical parameters and to research the possibility of applying theoretical laws of distribution to the time series of water mineralization.This research presents the results of the application of standard statistical methods of hydrometeorological information processing for data on water mineralization at 28 gauges of the Dnipro basin (within Ukraine) for the period from 1990 to 2015. The dynamics of the obtained statistical parameters (long-term annual average, coefficients of variation, asymmetry and autocorrelation) within the Dnipro basin in Ukraine has been analyzed. The average annual values of mineralization vary substantially within the studied part of the Dnipro basin - in the northern part the maximum value of the annual average mineralization is 447 mg/l, as it moves to the south, the mineralization increases and in the sub-basin of the Middle Dnipro it reaches a maximum of 971 mg/l; the highest values are observed in the south (sub-basin of the Lower Dnipro), where they can reach extremely high values for particular small rivers (the Solon River - Novopavlivka village, 3356 mg / l). The long-term variability of mineralization in the rivers of the studied area is insignificant, and the autocorrelation coefficients of the mineralization series are quite high, in most cases they are significant and tend to decrease from the sub-basin of the Prypyat’ river in the north to the sub-basin of the Lower Dnipro river in the south. Within the framework of the presented research, the possibility of using theoretical distribution curves known in hydrology to describe the series of river mineralization, using the example of the Dnipro basin, has also been analyzed. Using Pearson’s fitting criterion, the Pearson type III distributions and the three-parameter distributions by S.M.Krytsky and M.F.Menkel have been verified on their correspondence with the empirical series of mineralization. As a result, it was found that in 85% of cases the Pearson type III distribution can be used, and the three-parameter by S.M.Krytsky and M.F.Menkel can be used in 60% of cases.


Author(s):  

The main problems of an engineering hydrology connected with the analysis of non-stationary sequences of hydrological characteristics, statistical inauthenticity of estimates, uncertainty of long-term forecasts, taking into account the need of the accounting of anthropogenic factors of the runoff alterations are discussed. The novel complicated hydrological tasks reasons have been analyzed, problems of the extreme events hydrological analysis have been classified, issues of decision making in the various uncertain conditions have been explored. The problem of the input long-term forecast reliability in the process of water management computations has been studied with the Lake Baikal level fluctuations range as a study case. Relevant issues of the hydrological characteristics assessment in the conditions of future climatic changes uncertainty have been considered. The Bayesian method of probabilistic assessment of extreme water consumption and levels on water bodies in conjunction with possibilities of the long-term forecasting based on the atmosphere circulation models are recommended.


Author(s):  
A. N. Avlas ◽  
A. K. Demenchuk ◽  
S. V. Lemeshevskii ◽  
E. K. Makarov

The most commonly used methods for the medium- and long-term forecasting of epidemic processes are based on the classical SIR (susceptible – infected – recovered) model and its numerous modifications. In this approach, the dynamics of the epidemic is approximated using the solutions of differential or discrete equations. The forecasting methods based on the approximation of data by functions of a given class are usually focused on obtaining a short-term forecast. They are not used for the long-term forecasts of epidemic processes due to their insufficient efficiency for forecasting nonstationary processes. In this paper, we formulated a hypothesis that the primary waves of the COVID-19 pandemic, which took place in a number of European countries, including the Republic of Belarus, in the spring-summer of 2020 are isolated and therefore can be regarded as processes close to stationary. On the basis of this hypothesis, a method of approximating isolated epidemic process waves by means of generalized logistic functions with an increased number of exponents was proposed. The developed approach was applied to predict the number of infected people in the Republic of Belarus for the period until August 2020 based on data from the beginning of the epidemic until June 12, 2020.


2000 ◽  
Vol 179 ◽  
pp. 201-204
Author(s):  
Vojtech Rušin ◽  
Milan Minarovjech ◽  
Milan Rybanský

AbstractLong-term cyclic variations in the distribution of prominences and intensities of green (530.3 nm) and red (637.4 nm) coronal emission lines over solar cycles 18–23 are presented. Polar prominence branches will reach the poles at different epochs in cycle 23: the north branch at the beginning in 2002 and the south branch a year later (2003), respectively. The local maxima of intensities in the green line show both poleward- and equatorward-migrating branches. The poleward branches will reach the poles around cycle maxima like prominences, while the equatorward branches show a duration of 18 years and will end in cycle minima (2007). The red corona shows mostly equatorward branches. The possibility that these branches begin to develop at high latitudes in the preceding cycles cannot be excluded.


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