Changes in discharge regimes in the middle course of the Sava River in the 1931–2010 period

Author(s): Mladen Maradin,Ivan Canjevac,Danijel Orešic / Language(s): English / Issue: 151/2017

In order to analyse discharge regimes in the middle course of the Sava River (Croatia and Bosnia and Herzegovina), three hydrologic stations were chosen, having homogenous as well as continuous data in the observed 1931–2010 period. Those stations are Rugvica at the beginning of the middle course of the Sava River, station Jasenovac located just forehead of the Una River mouth and all the other large tributaries from Bosnia and Herzegovina and station Županja near the end of the middle course of the Sava River. At all three stations, there are notable negative trends of annual mean (all stat. significant) and minimum discharges for the whole period. At the same time, only in the upper part of the middle course of the Sava River maximum annual discharges have a positive trend, contributing to more unfavourable regime characteristics. At all three stations a cyclic variation of mean annual discharges is observed, likely to be linked to the cyclic variation of annual precipitation in the area of the basin. According to the latest discharge regime typology of the region the discharge regime at Rugvica is of Peripannonian pluvial-nival type, while the discharge regimes downstream, at Jasenovac and Županja fall into Pannoninan pluvial-nival type. A comparison of discharge regimes established for two past climatological standard reference periods 1931–1960 and 1961–1990 as well as for the contemporary 30-year period 1981–2010 lead to a conclusion that important changes in mean monthly discharges yearly course already occurred in the climatological standard reference period 1961–1990 compared to the previous one. In 1961–1990 period the autumn season discharge decreased, which is almost solely a result of a large fall in the November mean monthly discharge at all stations. Furthermore, in the same 1961–1990 period a transition of the primary maximum in the annual course of mean monthly discharges from November to December and of the secondary maximum from March to April occurred, which is preserved in discharge regimes in the middle course of the Sava River. Discharge regimes in the middle course of the Sava River in the contemporary period are characterised by decreased summer and even spring time discharges, which is linked to the trend of raising air temperatures, an increase in potential and real evapotranspiration and to a slowly decrease in annual precipitation, particularly in the summer season as established in spatially relevant previous climatological research.

Changes in precipitation over the East Herzegovina region

Author(s): Tatjana Popov,Slobodan Gnjato,Goran Trbic / Language(s): English / Issue: 1/2019

Changes in annual and seasonal precipitation over the East Herzegovina region in Bosnia and Herzegovina during the 1961-2016 periods were analyzed based on data sets of daily precipitation from 14 meteorological stations and rainfall gauges. The results show a downward trend in annual precipitation over the entire East Herzegovina region. Seasonal trend analysis showed that negative trends prevailed throughout the year, except in autumn season. Most prominent negative trends were registered in summer season throughout the region. In winter and spring season, precipitation displayed trends of both sign (although a downward trend prevailed). In the autumn season, precipitation has increased almost throughout the entire East Herzegovina region. However, a majority of estimated trends in annual and seasonal precipitation were weak and statistically insignificant. Prevailing negative values of the Rainfall Anomaly Index since the 1990s also suggest that precipitation reduction was present over the East Herzegovina region. Analysis of the Cumulative Precipitation Anomalies showed that a dry period started in 1981 and still continues. Precipitation variability was strongly dictated by the large-scale atmospheric circulation patterns over the Northern Hemisphere, such as the North Atlantic Oscillation, the East Atlantic/West Russia pattern and the Arctic Oscillation, particularly during winter season.

CHANGES IN TEMPERATURE EXTREMES IN BOSNIA AND HERZEGOVINA: A FIXED THRESHOLDS-BASED INDEX ANALYSIS

Author(s): Tatjana Popov,Slobodan Gnjato,Goran Trbic / Language(s): English / Issue: 1/2018

The paper analyzes trends in the extreme temperature indices based on fixed thresholds in Bosnia and Herzegovina during the 1961–2016. Based on data from 12 meteorological stations, trends in both warm and cold temperature indices were determined using the nonparametric Mann-Kendall test and the nonparametric Sen’s slope estimator. The observed tendencies in indices based on fixed thresholds were as expected in a warming world – warm temperature indices (summer days, tropical days and tropical nights) displayed the significant positive trends, whereas cold temperature indices (icing days and frost days) showed the downward tendencies. The annual occurrence of summer days and tropical days increased on average for 5.3 and 4.8 days per decade, respectively, whereas icing days and frost days displayed downward trends in the range of -1.7 and -3.6 days per decade, respectively. The obtained results indicate that the climate system warming was more a result of very pronounced positive trends in the warm temperature indices than the downward tendency of cold ones. The most prominent changes were observed in Banja Luka, Bugojno and Zenica regions. Both trends, positive in warm indices and negative in cold ones, become more pronounced in the 1990s and particularly since the beginning of the 21st century. Further research should focus on the assessment of the observed trends impacts on natural and socio-economic systems.

Channelling Foreign Policy Through Local Activities in China: City of Guangzhou Case Study

Author(s): Dominik Mierzejewski / Language(s): English / Publication Year: 0

Chemical composition of utility water in the arid climate zone on the examples of Kébili and Medenine regions (southern Tunisia)

Author(s): Karolina Sobczak-Szelc,Beata Latos,Anna Szczucinska,Rafal Kozlowski,Krzysztof Skocki / Language(s): English / Issue: 155/2018

Areas located within the hot, arid zone are characterized by extremely low availability of fresh water. In the Tunisian regions of Kébili and Medenine, deep-water sources and connate groundwater constitute its main sources. Surface waters, as well as shallow groundwaters found in those areas, are affected by a high level of salinity, which significantly reduces their use for either drinking or agriculture. Due to intensifying droughts the rainwater accumulation system, neither fulfils the needs of residents nor the developing agriculture. Waters in the oases of El Faour (Kébili) and Beni Kchedeche (Medenine) were analyzed in 2017 to find out their chemical composition, as well as their suitability for irrigation. The chemical composition of the investigated waters is dominated by the Na+, Ca2+, Cl– and SO4 3– ions.

Chromitites from the Sudetic ophiolite: origin and alteration

Author(s): Katarzyna Delura / Language(s): English / Publication Year: 2012

This book presents the petrological and chemical features of high-Al chromitites associated with serpentinized ultramafic rocks of mantle origin in the Jordanów-Gogołów and the Braszowice-Brzeźnica massifs (Sudetes Mts., Poland) as well as the metamorphic processes of chromian spinel and associated silicate minerals. Collected data suggest that models of the Sudetic ophiolite formation have to be revised. The monograph is intended for experts and students in the field of Earth sciences.

Circulation epochs based on the Vangengeim-Girs large scale patterns (1891–2010)

Author(s): Jan Degirmendžic,Krzysztof Kozuchowski / Language(s): English / Issue: 17/2018

This paper presents the results of an investigation of the variability in macro-circulation forms at the mid-tropospheric level distinguished in the Vangengeim-Girs (V-G) classification. The annual frequencies of circulation forms in the years 1891–2010 proved significant fluctuations, which provided the basis for distinguishing 7 circulation epochs. The epochs illustrate secular changes in the character of dominant forms – zonal circulation (W) prevailed at the turn of the 20th century; meridional forms E and C developed next, and zonal circulation began to dominate again after 1990.

CLIMATE CHANGE IN THE EASTERN ALPS AND THE FLOOD PATTERN OF THE DRAVA RIVER

Author(s): Dénes Lóczy,József Dezso,Péter Gyenizse / Language(s): English / Issue: 13/2017

A remarkable temperature rise (above the world average of 0.2°C per decade) is predicted for the Alpine section of the Drava catchment with higher likelihood than changes in the amount and annual regime of precipitation. Monthly precipitation data show increasing values in the northeast and characteristic dropping trends in southern part of the basin, with growing drought hazard. A simple correlation between long-term precipitation (daily, weekly and monthly values) and Drava discharge cannot be found from meteorological records. A possible explanation is that runoff generation also depends on the form of precipitation, water saturation of soils and vegetation cover. Since these factors are all related to climate change, the paper investigates whether the annual pattern of floods on the Drava River depends more closely on snow melt or on the duration and amount of rainfall. As opposed to snow depth and days with snow cover, soil saturation in summer shows an increase in the upper catchment. While large-scale spring melt is gradually shifting to earlier dates, early spring high water levels do not reach flood levels. It is investigated how the distribution of precipitation along the upper Drava and upper Mura control flood response in the lower Drava catchment.

CLIMATE OF SOKOBANJA BASIN AND ITS INFLUENCE ON THE DEVELOPMENT OF AGRICULTURE

Author(s): Mila Pavlovic,Aleksandar Radivojevic,Ljiljana Dimitrijevic / Language(s): English / Issue: 1/2011

The climate of Sokobanja basin has a significant influence on forming the economic character of this area. In the relation with other, primarily physical-geographical characteristics, climate of the Sokobanja basin has one of the greatest influences on the activities of the people who live there. The aim of this work is to analyze the basic climate elements and accordingly perceive their influence on the development of agriculture, as one of the most important activities of the population of this area.

Climate risks in the Babadag Plateau, Dobrogea, Southeastern Romania.

Author(s): ?TEFAN IONU? SAVA / Language(s): English / Issue: 1/2019

Climatic risk phenomena are researched and monitored by specialized institutions at both national and international level, due to their important economic and environmental impact. The purpose of this study is to know in detail the climatic risks to which the Babadag Plateau is subjected and the effects they have on society and the environment. Based on the official data recorded during 1965-2005, at the analyzed meteorological stations, maps were developed through the GIS (Geographic Information System) software, graphical representations for a better comparison of the particularities of climatic risk phenomena, and several specialized bibliographic sources were consulted. The results of the study highlight the fact that the Babadag Plateau can be subject to climatic risks throughout the year. The need for knowledge of these phenomena is imposed by the consequences they have on the economy, society and agricultural activities carried out within that territory.

CLIMATE TRENDS OF TEMPERATURE AND PRECIPITATION IN NIŠAVA RIVER VALLEY (SERBIA) FOR 1960-2015 PERIOD

Author(s): Marija Prokic / Language(s): English / Issue: 1/2018

Since climate plays a crucial role on our planet and is an inseparable part of all human activities, it is necessary to precisely record all parameters in order to estimate current climate conditions, climate characteristics of a certain region, as well as to try to predict and calculate further trends of climate change. Therefore, for the purpose of this paper, air temperature and precipitation of four meteorological stations in the Nišava river valley in Southeastern Serbia (municipalities of Dimitrovgrad, Pirot, Bela Palanka and Niš) have been considered for the period 1960–2015 along with statistical methods for analysis of these parameters and prediction of their trends. Results have shown that there is a positive trend in mean annual air temperatures and average seasonal air temperatures for the whole region which can influence natural processes and human activities. For precipitation, it can be concluded that no significant change in mean annual precipitation for the observed period has occurred. However, there is a great difference in the amount of precipitation between consecutive years, especially from 2000 onwards which can cause very dry years or years with floods

Climate Variability in Spring 2019 In South-West Romania.

Author(s): Octavia Bogdan,Ion Marinica,ANDREEA FLORIANA MARINICA / Language(s): English / Issue: 2/2019

In 2019, the solar activity reached a minimum, the El Nino phenomenon was absent, carbon dioxide concentrations exceeded 410 ppm (the highest level in the last 120,000 years), and climate warming continued. As a result, in southwestern Romania (and not only), the climatic evolutions were marked by a great variability. The warming of the weather started from 14.I.2019 and culminated with the warm March. On 18.III in Romania, the European climatic record of the hottest day of March 18 in the last 120 years was recorded. The precipitations were deficient for extended periods of time, March being excessively dry, and April even on average rainfall, but in areas extended especially in the Oltenia Plain and in the hills area, the drought persisted. The strong instability of the weather that started on 20.IV.2019 and culminated with torrential rains that caused flooding in some areas, abundant hail and tornadoes between 30.V-6.VI, which brought a completion of water supply. The recording of the first moderate heat wave in the period 10-16.VI has restored the drought problem. The paper analyzes the climate variability of spring 2019 and its synoptic causes.

Comparative Analysis Of The Flow Activity Of The Homoljska Potajnica Intermittent Spring

Author(s): Nikola Igracev / Language(s): English / Issue: 1/2014

Homoljska Potajnica belongs to the type of a very rare, intermittent or rhythmic springs which appear exclusively in karst areas. It is one of the three known springs of this type in Serbia, while it is believed to be only about fifty of these in the rest of the world. As a rare karst and natural phenomenon, Homoljska Potajnica was a subject of interest for numerous researchers and geomorphologists in Serbia. Due to a very complex problem of occurence and the principle of functioning, to get the reliable data of how intemittent springs work, it is neccesarry to provide a continious observations, ussually in a long term period. This paper presents the results of the measurements of spring's flow activity and water discharge, taken in 2012. and 2013. These were carried out for comparison with the results of previous research, with an aim to determine possible changes in dynamics and mechanisms of spring's functioning in the past. One of the goals is to relate the annual precipitation regime with the intensity and frequency of spring activity, to try to determine the specific model of the spring's functioning. Another goal is to emphasize the need for continious observation in order to obtain the relevant data about the evolution of this rare natural phenomenon.

Comportarea stâlpilor LEA la fenomene meteorologice extreme

Author(s): Cristina Câmpian,Vincentiu IUHOS,Septimiu BOTA,Maria Pop / Language(s): Romanian / Publication Year: 0

The study aims to an analysis for the overhead power lines columns (LEA) with high voltage subjected to extreme weather phenomena. The overhead power lines columns is a complex study that brings together specialist in the domain of civil, industrial and also in the electrical engineering. LEA overhead power lines columns are usually anchored with trusses having round or polygonal sections. The purpose of the study is the analysis of two types of overhead power columns: one bay opening and a tower two-way consoles. The analysis goes through all the necessary steps for the design and verification of the resistance elements. The assessment of the loading configuration for these types of elements are: dead loads of the power line and elements of the column, loads from the deposits of chicory and wind action.

Conclusions

Author(s): Tomasz Kaminski,Malgorzata Pietrasiak,Dominik Mierzejewski,Grzegorz Bywalec,Michal Slowikowski / Language(s): English / Publication Year: 0

Conferinţa de cercetare în construcţii, economia construcţiilor, urbanism şi amenajarea teritoriului. Rezumate ale lucrărilor

Author(s): / Language(s): Romanian / Publication Year: 2012

Includes abstracts of the papers presented in the research conference on constructions, economy of constructions, architecture, urbanism and territorial development, editions 1-4.

Conferinţa de cercetare în construcţii, economia construcţiilor, urbanism şi amenajarea teritoriului. Rezumate ale lucrărilor

Author(s): / Language(s): English,Romanian / Publication Year: 2013

Includes abstracts of the papers presented in the research conference on constructions, economy of constructions, architecture, urbanism and territorial development, 6th edition.

Conferinţa de cercetare în construcţii, economia construcţiilor, urbanism şi amenajarea teritoriului. Rezumate ale lucrărilor

Author(s): / Language(s): English,Romanian / Publication Year: 2015

Includes abstracts of the papers presented in the research conference on constructions, economy of constructions, architecture, urbanism and territorial development, 10th edition.

Conferinţa de cercetare în construcţii, economia construcţiilor, urbanism şi amenajarea teritoriului. Rezumate ale lucrărilor

Author(s): / Language(s): English,Romanian / Publication Year: 2016

Includes abstracts of the papers presented in the research conference on constructions, economy of constructions, architecture, urbanism and territorial development, 12th edition.

Conferinţa de cercetare în construcţii, economia construcţiilor, urbanism şi amenajarea teritoriului. Rezumate ale lucrărilor

Author(s): / Language(s): English,Romanian / Publication Year: 2017

Includes abstracts of the papers presented in the research conference on constructions, economy of constructions, architecture, urbanism and territorial development, 13th edition.