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1

Analysis and Mapping of Water Erosion Vulnerability Using GIS for the Mghila Watershed, Northwest of Algeria

Ratiat Abdelkader, Haddad Ali, Bouaichi Ilham, Matene Chahrazed Naziha

Archives of Hydro-Engineering and Environmental Mechanics

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2023

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Vol. 70, nr 1

71--87

EN

Intensification of extreme rainfall-runoff events in arid and semi-arid regions because of climate change induce the water erosion that contributes considerably to the loss of vegetal layers of soils and reduce the storage capacity of dams by silting of transported sediments from the watershed to the impoundment. This paper aims at proposing means for protecting the Mghila dam against silting by identification and delimitation of vulnerable areas to water erosion. This dam, built in the North-West of Algeria, ensures irrigated cultivation. Topographical, geological, and land use characteristics of the watershedwere analyzed using the geographic information system (GIS). Analysis of results has allowed the identification by area percentage four-vulnerability classes with sensitivity to the water erosion: low (18.89%), medium (13.08%), high (65.05%) and very high (8.38%). The spatial distribution of the lithological substratum friability, the vegetation cover and slope degrees have led to the development of an efficient strategy for the watershed management in order to reduce the effect of water erosion on soil degradation and silting of the Mghila dam.

2

Spatio-Temporal Model of Extreme Rainfall Data in the Province of South Sulawesi for a Flood Early Warning System

Bakri Bambang, Adam Khaeryna, Rahim Amran

Geomatics and Environmental Engineering

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2021

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Vol. 15, no. 2

5--15

EN

In this study, we model extreme rainfall to study the high rainfall events in the province of South Sulawesi, Indonesia. We investigated the effect of the El Nino South Oscillation (ENSO), Indian Ocean Dipole Mode (IOD), and Madden-Julian Oscillation (MJO) on extreme rainfall events. We also assume that events in a location are affected by events in other nearby locations. Using rainfall data from the province of South Sulawesi, the results showed that extreme rainfall events are related to IOD and MJO.

3

Quantile trends of subhourly extreme rainfall: Marmara Region, Turkey

Oruc Sertac

Acta Geophysica

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2021

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Vol. 69, no. 6

2453--2473

EN

Global climate change will probably cause intensification of the hydrologic cycle, which can lead to alterations in extreme precipitation properties. In this study, we investigated the trend of 5-, 10-, 15-, and 30-min annual maximum rainfall series at 12 stations in the Marmara Region, Turkey, using quantile regression. The data ranges were from 46 to 71 years long. Five quantiles were used to examine the extreme rainfall series, and their quantile regression parameters were calculated. The results show that quantile regression is a powerful tool to compute trends with a more inferential context, which was validated with the notable differences between the trends at chosen quantiles and the classical ordinary least squares method. Concerning the problem of the analysis of climate trends, the quantile regression method seems to provide a perspective from a more detailed understanding of processes in the climate system in terms of characteristics of climate variability and extremity.

4

Extreme precipitation indices trend assessment over Thrace region, Turkey

Oruc Sertac, Yalcin Emrah

Acta Geophysica

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2021

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Vol. 69, no. 1

307--321

EN

The frequency and the severity of extreme weather events are increasing globally and will continue to do so in the coming decades as a consequence of our changing climate. Understanding the characteristics of these events is crucial due to their signifcant negative impacts on social, physical and economic environments. In this study, 14 extreme rainfall indices are determined and examined in terms of trends and statistical characteristics for the four meteorological stations located in the Thrace region of Turkey, namely Edirne, Tekirdag, Kirklareli and Sariyer (Istanbul). The results indicate that annual total precipitation has an increasing trend for the Kirklareli and Sariyer stations (z=1.730 and z=2.127) and a decreasing trend for the Edirne and Tekirdag stations (z=− 0.368 and z=− 0.401). However, the precipitation intensity indices (SDII) of all stations show increasing trends that are statistically signifcant for the Edirne and Kirklareli stations. The Kirklareli station tends to have more days with heavy, very heavy and extremely heavy rainfall events (z=2.241, z=2.076 and z=1.684, respectively). It is also anticipated that maximum amount of rainfalls in daily and consecutive fve- and ten-day time scales will probably increase at all stations. Moreover, rainfall from very wet days and extremely wet days and fraction of total wet day rainfall that comes from very wet days and extremely wet days indices also show increasing trend tendencies for all stations. The remarkable point is the decreasing total precipitation trend at the Edirne and Tekirdag stations, contrary to the Kirklareli and Sariyer stations, which indicates that the annual total precipitation does not necessarily depend on extreme precipitation for the analyzed period.

5

Modelling spatial variation of extreme precipitation over Ho Chi Minh City under nonstationary conditio

Binh Le Thi Hoa, Agilan V., Umamahesh N. V., Rathnam E. V.

Acta Geophysica

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2019

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Vol. 67, no. 3

849--861

EN

Understanding the magnitude and spatial variation of extreme rainfall events are required for decision making and adaptation strategies for flood risk. In Ho Chi Minh City (HCMC), heavy rainfall, which is considered as a main cause of floods, witnessed an increase in frequency and magnitude in last few decades. Although nonstationarity in extreme rainfall has been proved in many places of the world, research into nonstationarity feature in extreme rainfall in HCMC has not been paid attention thoroughly. In this study, the spatial variation of extreme precipitation over Ho Chi Minh City is modelled under nonstationary condition. The generalized extreme value (GEV) distribution with location made a nonlinear function of time is applied to annual maximum daily rainfall. The study results show that the nonstationary GEV model is found to be superior in capturing extreme precipitation events when compared to the stationary GEV model. The extreme rainfall estimates under the stationary condition are lower than those under the nonstationary condition in most stations. Besides, the spatial variation of extreme rainfall under nonstationary condition shows a significant difference in extreme estimates between the periods of 1980–1984 and 2010–2014 in study area.

6

Mean annual precipitation in a mountain river catchment area in the period 1984-2012 (the case of Kamienica river)

Cupak A., Górka A., Michalec B., Wałęga A.

Geomatics, Landmanagement and Landscape

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2016

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no. 2

31--40

EN

The aim of the study is to evaluate the mean annual precipitation in the mountain river catchment area, in the period between 1984-2012. Data on daily rainfall totals was obtained from IMGW PIB in Warsaw, and it came from two weather stations: one in Nowy Sącz, and the other in Krynica. It has been demonstrated that during the multi-year period covered by the study, there were variations in terms of precipitation levels; the year 1987 should be considered e¬tremely dry, while 2010, extremely wet - in the latter year, extreme rainfall was noted. In the analysed multi-year period, within the total annual precipitation, rain dominated during the first half year, which undoubtedly affects the hydrological regime of the Kamienica river.

PL

Celem pracy jest ocena kształtowania się charakterystyk opadu na obszarze górskiej rzeki Kamienicy w wieloleciu 1984-2012. Dane dotyczące sum dobowych opadów pozyskano z IMGW PIB w Warszawie i pochodziły z dwóch stacji opadowych: Nowy Sącz i Krynica. Wykazano, że w badanym wieloleciu występowały zróżnicowane lata pod względem wilgotności; za szczególnie suchy należy uznać 1987 rok, a wilgotny to 2010 rok, gdyż w tym roku występowała największa liczba opadów ekstremalnych. W badanym wieloleciu w sumie rocznej opadów dominowały opady z półrocza letniego, co niewątpliwie wpływa na reżim hydrologiczny rzeki Kamienicy.

7

Opady nawalne i powodzie miejskie. Wytyczne postępowania w zakresie komunalnej ochrony przed powodziami

Illgen M., Kissel M., Piroth K.

Technologia Wody

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2014

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Nr 1 (33)

56--63

PL

Zapobieganie powodziom spowodowanym deszczami nawalnymi na terenach miejskich jest wspólnym zadaniem służb komunalnych, dla których dotychczas nie istnieją powszechnie przyjęte algorytmy postępowania. Międzyinstytucjonalna grupa robocza DWA/BWK „Deszcze nawalne i zapobieganie powodziom” przygotowała praktyczny przewodnik w zakresie możliwości profilaktyki przeciwpowodziowej oraz zalecenia postępowania dla decydentów i projektantów. Przewodnik pokazuje, na podstawie obrazowych przykładów, jak można rozpoznać zagrożenia zalania obszarów zamieszkałych, jak konkretnie mogą wyglądać infrastrukturalne i obiektowe działania zapobiegające zalaniom i kto powinien brać udział w przygotowaniu tych działań. Opisane zostały zarówno działania planistyczne, techniczne, jak i administracyjne na poziomie komunalnym i prywatnym. Niniejszy artykuł przedstawia ogólne zarysy wspomnianego przewodnika.

EN

The prevention of flooding due to heavy rainfall in urban areas is a common task for local communities for which, however, there are no established action patterns. A cross-cutting DWA/BWK working group on “heavy rainfall and flood prevention” has now compiled a list of possible actions that can be taken by local communi¬ties to prevent flooding and it has developed guidelines that contain real-life oriented recommended courses of action for technical planners and decision makers in local communities. On the basis of a number of very telling examples, these practical guidelines show how flooding risks in residential areas can be identified, what concrete shape infrastructure and site-related flood prevention measures can take, and which actors must be involved. Planning, engineering and administrative preventive action at the local community and at the private level are discussed. The paper outlines the main features of the guidelines.

8

Water management and flood protection of the polders in the Netherlands under the impact of climate change and man-induced changes in land use

Schultz B.

Journal of Water and Land Development

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2008

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no. 12

71-94

EN

Two-third of the area of the Netherlands is flood prone. Storm surges at the North Sea , floods in the rivers, failure of secondary dikes, as well as heavy rainfall may cause flooding. Most of the flood prone areas rely for their existence on drainage by pumping, because their surface level may be permanently or during floods up to several metres below the surrounding water levels. During the past decades climate change is generally felt as a reason for major concern. However, the impacts of climate change on increase in extreme conditions may be up to 45% per century. If we look at the man-induced changes in land use, due to increase in population and rapid increase in the value of public and private property, then one may observe an increase of 100-1,000% per century. One should therefore wonder what would have to be our major concern. In the paper the relevant processes are described, based on some characteristic data on water management and flood protection in the Netherlands . It is shown that impacts of climate change on water management and flood protection may be expected, but that such impacts can easily be accommodated during improvement works on water management systems and flood protection provisions that from time to time will be required. It will be much more important to take carefully into account the risk of flooding in the planning of land use development, especially for valuable types of land use like urban and industrial areas, green houses and recreation areas.

PL

Dwie trzecie powierzchni Holandii jest narażonych na powodzie. Sztormowe spiętrzenia wód na Morzu Północnym, wysokie stany wody w rzekach, awarie obwałowań rowów czy obfite opady mogą powodować powodzie. Użytkowanie obszarów narażonych na zalewanie zależy od stałego odwodnienia i od pompowania wód, ponieważ ich powierzchnia może (trwale lub tylko w czasie zalewu) znajdować się do kilku metrów poniżej poziomu otaczających wód. W ciągu ostatnich dziesięcioleci zmiany klimatu są postrzegane jako główny powód do niepokoju. Jednakże, wpływ zmiany klimatu może spowodować straty w wyniku wzrostu zjawisk ekstremalnych do 45% na stulecie. Jeśli spojrzymy na wywołane przez człowieka zmiany w użytkowaniu ziemi spowodowane przyrostem zaludnienia i gwałtownym wzrostem wartości infrastruktury to stwierdzimy, że przyrost strost może wynieść od 100 do 1000% na stulecie. W związku z tym należy zapytać, co powinno być przedmiotem naszej szczególnej troski? W oparciu o charakterystyczne dane dotyczące gospodarki wodnej i ochrony przeciwpowodziowej w Holandii opisano w pracy wyniki analiz prognostycznych. Wykazano, że można oczekiwać wpływów zmian klimatu na gospodarkę wodną i ochronę przeciwpowodziową, ale te wpływy dadzą się łatwo uwzględnić przy pracach związanych z usprawnianiem systemów gospodarki wodnej czy środków ochrony przeciwpowodziowej, które od czasu do czasu trzeba będzie podejmować. Daleko bardziej istotne będzie zwrócenie szczególnej uwagi na ryzyko powodziowe w planowaniu przestrzennym, zwłaszcza w odniesieniu do zagospodarowania cennych obszarów takich jak tereny miejskie czy przemysłowe, obiekty ekologiczne czy tereny rekreacyjne.