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1

Soft postglacial cliffs in Poland under climate change

Różyński Grzegorz, Cerkowniak Grzegorz

Oceanologia

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2024

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Vol. 66 (2)

319--333

EN

The paper presents the results of the simulations of soft cliff erosion in Poland under future sea level rise. Two locations were investigated: one situated on the Wolin island, and the second near the town of Ustka. The cliffs will be suffering enhanced erosion for a number of reasons. First, the adopted sea level rise of 0.7 m results in a direct attack on cliff foot, leading to enhanced erosion with rates being roughly twice as high as that occurring without the rise. A high rate of erosion can persist because the cliff cannot reconfigure itself by moving landward and will permanently remain exposed to wave attack even under milder regimes. Second, the wave climates in the Baltic Sea release most energy in close shoreline proximity. Third, longer storm event durations can lead to ‘erosion saturation’, but this result requires further investigations, which will include alongshore effects induced by local bathymetry and longshore currents, ignored in 1-D simulations. Finally, the granulometry was found less important; finer grains offer less resistance to depletion, leading to greater erosion. The results demonstrate the need for vast follow-up research: (1) detailed mapping of the bathymetry near cliffs in order to properly reproduce alongshore redistribution of sediment during storms and achieve better estimates of cliff erosion, (2) detailed mapping of cliff lithology in order to properly reproduce their sediment composition and thus achieve better estimates of built-in susceptibility to erosion, (3) preparation of 2-D modeling suites for improved assessment of the rates of erosion of cliffs subjected to sea level rise.

2

Kamienie milowe & wyzwania ekonofizyki a także socjofizyki cz. 1

Kutner Ryszard

Postępy Fizyki

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2022

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T. 73, z. 1

11--20

PL

Omówiono kamienie milowe ekonofizyki a także socjofizyki wybrane w kontekście wyzwań, jakie stawia współczesna społeczno-ekonomiczna rzeczywistość. Wskazano na ich rolę w budowaniu obszarów badawczych ekonofizyki i socjofizyki [1, 2, 3, 4 ].

EN

We discuss the milestones of econophysics and sociophysics. We chose them in the context of the challenges posed by contemporary socio-economic reality. We indicate their role in building research areas in econophysics and sociophysics [1, 2, 3, 4 ].

3

Statistical analysis of Mediterranean coastal storms

Martzikos Nikolas T., Prinos Panayotis E., Memos Constantine D., Tsoukala Vasiliki K.

Oceanologia

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2021

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No. 63 (1)

133--148

EN

Coastal storms as extreme hydrometeorological events have severe impacts on the coasts and consequently affect the coastal communities, attracting considerable research interest nowadays. Attempting to understand the risk of these extreme events, a coastal storm analysis is accomplished by studying the parameters which define a coastal storm and their properties, such as the wave height, the wave period, the duration, the calm period, and the storm energy. The frequency of occurrence of coastal storms, the thresholds of storm parameters and the way they are interrelating with each other draw a rough outline of wave climate during coastal storm events for a specific location. This information is valuable afterwards for the design of coastal structures and the coastal zone management. In this work, buoy datasets from 30 locations in the Mediterranean Sea are analysed for describing coastal storm activity. A sample of 4008 coastal storms is identified. Each location faces around 10-14 coastal storms per year, with most of them to occur in winter months and their characteristics to be site-dependent. Their average duration is lower than 30 hours, and 25% of them are consecutive events which hit the same location in less than a day. Furthermore, the wave period and the main direction present no remarkable fluctuations during a coastal storm. With this analysis, a deeper understanding of coastal storm severity is pursued, gaining knowledge about their past activity, in order to be prepared in the future and to protect the coastal areas.

4

Probability distribution functions for service loads of frame scaffoldings

Błazik-Borowa Ewa, Pieńko Michał, Szer Iwona, Hoła Bożena, Czarnocki Krzysztof

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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Vol. 69, nr 2

art. no. e136734

EN

The paper discusses service load measurements (weight of construction materials, small equipment and workers) conducted on 120 frame scaffoldings all over Poland in 2016‒2018. Despite the fact that the scaffolding should ensure the safety of its users, most accidents on construction sites are caused by fall from height. Service loads are one of the elements affecting the safety of scaffolding use. On the basis of the studies, maximum load on one platform and maximum load on a vertical scaffolding module for one day were obtained. They were treated as the random variables of the maximum values. Histograms and probability density functions were determined for these variables. The selection of a probability distribution consisted in the selection of a probability density function by means of fitting curves to the study result histograms using the method of least squares. The analysis was performed for distribution Weibull and Gumbel probability density functions which are applied for maximum values of random variables. Parameters of these functions can be used for the purposes of the reliability analysis to calibrate partial safety factors in simulation of service load during the scaffolding failure risk assessment. Besides, the probability of not exceeding the standard loads provided for frame scaffoldings for 120 weeks was established on the aforementioned basis. The results of the presented research show that in Poland there is a high probability of exceeding the permissible service loads in one year and thus there is a high risk of scaffolding damage.

5

Relationship between selected percentiles and return periods of extreme events

Camufo Dario, Becherini Francesca, della Valle Antonio

Acta Geophysica

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2020

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Vol. 68, no. 4

1201--1211

EN

This paper investigates the relationship between selected percentiles, return periods and the concepts of rare and extreme events in climate and hydrological series, considering both regular and irregular datasets, and discusses the IPCC and WMO indications. IPCC (Annex II: Glossary. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. IPCC, Geneva, 2014) establishes that an extreme event should be rare and exceed selected upper and lower thresholds (10th and 90th percentiles); WMO (Guidelines on the defnition and monitoring of extreme weather and climate events-TT-DEWCE WMO 4/14/2016. World Meteorological Organization, Geneva, 2016) suggests thresholds near the ends of the range, but leaves them undetermined. The concept of “rare” relates the extreme events to the time domain and is typically expressed in terms of return period (RP). The key is to fnd the combination between “rare”, percentile and return period. In particular, two crucial items are analysed: (1) how the return period may vary in response to the choice of the threshold, in particular when it is expressed in terms of percentiles; (2) how the choice of producing a regular or irregular dataset may afect the yearly frequency and the related return periods. Some weather variables (e.g. temperature) are regular and recorded at fxed time intervals, while other phenomena (e.g. tornadoes) occur at times. Precipitation may be considered either regular, all-days being characterized by a precipitation amount from 0 (no precipitation) to the top of the range, or irregular (rainy-days only) considering a precipitation day over a selected instrumental or percentile threshold. These two modes of interpreting precipitation include a diferent number of events per year (365 or less) and generate diferent return periods. Every climatic information may be afected by this defnition. The 90th percentile applied to observations with daily frequency produces 10-day return period and the percentiles necessary to get 1 year, 10 years or other return periods are calculated. The general case of events with selected or variable frequencies, and selected percentiles, is also considered with an example of a precipitation series, two-century long.

6

The impact of hydrometeorological events on the state of the urban river quality

Pietruszyński Łukasz, Cieśliński Roman

Ecological Chemistry and Engineering. S

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2019

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Vol. 26, nr 3

521--533

EN

One of the aims of this paper was to study catchment and watercourse response to extreme events. The study area consisted of Orunski Stream in the northern Polish city of Gdansk. The study period (review of cartographic materials) covered the years 1908 to 2000, while field research covered the period from May 2009 to April 2010. In addition, measurements were performed to study the dynamics of changes occurring in the creek during rainfall events. Examination of the water chemistry changes made two days before heavy rainfall showed a significant increase in sulphates and nitrogen compounds. Additionally, pollutants washed from the basin contributed to a significant deterioration in the water colour. A rainfall of 1.3 mm caused an eleven-fold increase in stream flow, a twofold increase in the water level, and a fourfold increase in the velocity of water molecules. It might appear seem that such a small amount of rainfall would have no major effect on the hydrologic and hydrochemical parameters of a small creek. However, it is the maximum flow rate that is an important variable when assessing potential flood risk levels.

7

Ocena struktury czasowo-przestrzennej opadów z wkorzystaniem wybranych wskaźników do identyfikacji zdarzeń ekstremalnych

Szalińska W., Otop I.

Woda-Środowisko-Obszary Wiejskie

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2012

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T. 12, z. 2

269-282

PL

Intensywne opady mogą powodować zagrożenie oraz poważne skutki hydrologiczne (powodzie, wezbrania), zarówno lokalnie, jak i w skali regionalnej. Stopień zagrożenia powodowanego opadami zależy od wielu czynników, m.in. od wysokości opadów, czasu trwania, zasięgu przestrzennego oraz sposobu zagospodarowania danego obszaru. Celem badań było opracowanie zbioru wartości wskaźnikowych dobowych sum opadów, umożliwiających ocenę struktury czasowo-przestrzennej opadów pod kątem identyfikacji zdarzeń ekstremalnych, wpływających na zagrożenie hydrologiczne. Opracowany zbiór wskaźników obejmował wskaźniki aprioryczne i statystyczne. Wartości progowe wskaźników statystycznych wyznaczono na podstawie wieloletnich danych obserwacyjnych, analizując sumy, czas trwania i rozkład przestrzenny opadów. Wybrany zbiór wskaźników wykorzystano do oceny struktury czasowo-przestrzennej opadów w dorzeczu górnej i środkowej Odry w okresie czerwiec-lipiec 2009 oraz maj-czerwiec 2010 r. Wyznaczone wskaźniki mogą być wykorzystane w bieżącej ocenie warunków opadowych, a wraz z uwzględnieniem morfologii terenu i zagospodarowania danego obszaru - do oceny stopnia zagrożenia hydrometeorologicznego.

EN

Intensive rainfall events can cause severe hydrological threats and flooding. The scale of hydrological impact depends on the amount of precipitation, duration and spatial range. The aim of this work was to develop a set of indicators for the evaluation of daily sums of rainfall in order to identify extreme events triggering hydrological hazards. Indicator threshold values were assumed a priori or estimated from long-term observation dataset. A selected set of indicators was used to evaluate spatial and temporal structure of two precipitation events: June-July 2009 and May-June 2010. The obtained results showed the magnitude of extreme rainfall, frequency and duration as well as location of extreme events forming hydrological hazard in 2009 and 2010 in the upper and middle Odra River basin. Developed set of indicators can be used operationally to evaluate current rainfall situation and, in combination with the information on hydrological and catchment conditions, to assess hydrological risk.

8

The geomorphological effectiveness of extreme meteorological phenomena on flysch slopes

Gorczyca E.

Landform Analysis

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2008

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Vol. 6

15--27

EN

Extreme events tend to cause large-scale slope system changes. During the last ten years, a series of extreme meteorological events caused considerable transformation of the slopes and valleys in various parts of the Carpathian Mountains. This paper presents the geomorphological effects of extreme rainfall and thaw events on the slopes of two catchments: the lososina catchment (Beskid Wyspowy) and the Hoczewka catchment with an area around the Solinskie Lake (Bieszczady Niskie). The bulk of the discussion concerns a study carried out in the Lososina catchment after three separate extreme events that were followed by a considerable transformation of the slopes due to landsliding. The studies carried out in the Biesr.cr.ady Range, where a single extreme event produced only spatially limited effects, were mainly used for comparison. '[he disparity between the responses of the two slope systems was a result of differences between the systems themselves, including their geology, geomorphology and landslide record, and of the difference in the scale of the extreme events.

9

Blackout w rejonie Szczecina

Bartodziej G., Tomaszewski M.

Energetyka

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2008

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nr 10

682-684

PL

Zwiększenie odporności linii elektroenergetycznych na ekstremalne zdarzenia można osiągać w procesie projektowania nowych linii, a także poprzez dostosowanie niektórych istniejących linii do zwiększonych wymagań. Zakres ewentualnych modyfikacji musi wynikać z poszczególnych analiz techniczno-ekonomicznych dla rejonów szczególnie zagrożonych. Koszt działań prewencyjnych musi być w skali kraju i regionu niższy niż koszty prawdopodobnych awarii, przy obliczeniach obejmujących cykl życia linii i innych urządzeń sieciowych, a także uwzględniających reguły rynkowe.

EN

Increasing of power transmission lines resistance to extreme events can be obtained during the process of new lines designing and also by adapting some of the already existing lines to increased requirements. The range of possible modifications must be based on individual technical and economic analyses prepared for particularly imperilled regions. Cost of preventive activities - on country and region levels - must be lower than costs of probable failures, where calculations must not only be based on data concerning the lifetime of electric lines and other network installations but also taking into account free market rules.