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The climate changes represent an important problem in today's society. Our study refers to the West Region of Romania, formed by the counties of Arad, Timis, Caras-Severin, Hunedoara, and it shows that there are significant differences regarding the climate changes between these counties. In our paper, we analyze the evolution of annual, respectively seasonal precipitations, and of the minimal, maximal and medium air temperatures in the considered region in the time frame 1991-2021. The statistical analysis of data shows an increase of the medium annual air temperatures, the observed changes being more pronounced in summer and winter. Beside the increase tendency of the air temperature in winter, one could observe also that the time of heat waves has become significantly longer in the West of Romania, such that the number of hot days is larger. An increase of the maximum length of the periods without precipitation has been observed over the last decades in the west during summer, as well as monthly anomalies of temperatures and precipitations. Annual estimates of the Climate Altering Land Cover Index are presented for the analyzed period and we observe that there is a positive correlation between these indices and the mean air temperature. In conditions of the climate changes, the mean summer precipitations will reduce in the coming decades, which will affect the management of water resources and the agriculture, which leads to the necessity of adjustment to the climate changes. [ABSTRACT FROM AUTHOR]

This paper analyzes the changes of trends in temperature and precipitation in the Azov sea basin. The nature of this territory has undergone major changes. It is an important agricultural and industrial area. The paper considers changes in temperature and precipitation at stations located mainly in the steppe zone. Maximum, minimum, mean air temperature and precipitation trends on a seasonal and annual time scale are evaluated from data recorded at twelve weather stations in the basin of Azov sea during the period 1966–2015. Since the 70s of the twentieth century, there has been a monotonous increase in air temperature. The warmest years not only for Russia, but also for the Northern hemisphere and the globe as a whole were 2007, 2002, 2005 and 2004. Analysis of maximum air temperature values showed that the warmest years in the basin were 2010, 2007, and 2015. The minimum temperatures were recorded in 1987, 1976, 1992-1993 years. Over the past 15-20 years there have been significant changes in climate features. Annual and season changes are analyzed. It is established a steady warming trend. An increase in annual temperatures by 0.4-2.8 °C, January - by 2.6-3.1 °C and July - by 0.7- 2.1 °C. The study of air temperature by season showed that winter become warmer by 1.1 - 5.8 °C. The precipitation trend is less noticeable. In the winter and autumn periods there is an increase in the amount of precipitation. In the spring the amount of precipitation increases for all the stations under. In summer precipitation changes complicatedly. [ABSTRACT FROM AUTHOR]

The link between precipitation, drought indices, and NDVI is discussed in this paper. The data were processed on the example of the extreme eastern region of Georgia-Kakheti for the period 2016-2020. The study area has landscapes of natural (mixed and deciduous forests) and agriculture (vineyards, orchards, cereals, and vegetables). The NDVI was generated using Sentinel 2 images with a 10 m pixel resolution, and the average monthly NDVI was derived using Arc map 10.8. Drought indices (SPI and SPEI) were calculated according to the daily climate data from five rain gauges located in the study area in program R. Several trends emerged from the results. The correlation between NDVI, precipitation and drought indices vary according to natural and agricultural landscapes. A relatively low correlation was observed between the average monthly NDVI, precipitation and drought indices in the case of forests in Lagodekhi. These areas are relatively humid locations in Kakheti. In the southeast of the region, where arid forests are represented, NDVI was found to be more sensitive to precipitation and, consequently, drought indices. However, in contrast to the previously described locations, SPI and SPEI differed significantly from each other. In the case of agriculture landscapes, this connection is more complex and depends on the crop type and the vegetation period. [ABSTRACT FROM AUTHOR]

The article analyses the current state of flood protection of the urban area in the foothill region. Problems of the area were characterized through selected critical points that support the local flood origination. Of course, the flood is a random phenomenon and its behaviour depends on many other factors, such as soil saturation, vegetation cover, river bed channel current state, as well as drainage cuts, soil management, etc. For efficient design of the flood protection measures, it is necessary to have input data with a high degree of reliability. This is usually not ensured in such small regions because hydrological and precipitation data from gauging and precipitation stations are missing. Therefore, before the design of the flood protection measures, the inputs themselves (mostly hydrological) are simulated, which is a demanding process and the results have a high degree of uncertainty. In this paper, different outputs of flood hydrographs modelled in different methods are presented and compared. The hydrograph is used then as a direct input for the design of the flood protection measures. Therefore, the degree of its reliability affects the whole proposal not only from the economic point of view but mainly from the aspect of protection of the adjacent area. [ABSTRACT FROM AUTHOR]

Climate extremes affect directly social and ecological systems. Therefore, extreme climatic indices based on daily precipitation as well as maximum and minimum air temperatures have been derived. A detailed analysis of extreme precipitation patterns is essential for the development of monitoring and mitigation strategies.The analysis of eight precipitation-related extreme climatic indices (annual total precipitation (PRCPTOT), heavy precipitation days (R10), very heavy precipitation days (R20), very wet days (R95pTOT), maximum 1-day precipitation (RX1day), simple daily intensity (SDII), maximum 5-day precipitation (RX5day), and extremely wet days (R99pTOT)) are presented in this paper using data from three Hungarian meteorological stations (Budapest, Debrecen and Szombathely) for the period from 1960 to 2010. There is no significant difference in SDII, R10, R20 and R95pTOT indices at any of the analyzed stations. The RX1day and RX5day indices indicate increasing values at Budapest station after 1990. Similarly, the R99pTOT index had increased values at Budapest station for the period 2000–2010. The PRCPTOT values slightly decreased at Budapest and Szombathely stations in the entire period 1960–2010. [ABSTRACT FROM AUTHOR]

From fast-growing plants, Miscanthus is a promising alternative energy source exploitable at regional level. The climatic conditions in the region also have a significant impact on the biomass production and also on the economic efficiency. The aim of the paper was to evaluate the influence of selected climatic parameters on the total production of the above-ground biomass of two Miscanthus genotypes in the Nitra region in the Slovak republic for the years 2015-2018. The method of monitoring climatic parameters and the destructive method of determining the biomass yield of the above-ground organs were used. Based on an analysis of the total Miscanthus biomass production, it is possible to confirm a statistically significant difference in production in the monitored years. The influence of air temperature fluctuations in the spring months and the lack of precipitation at the time of the cumulation of shoots growth on the overall biomass production were also confirmed. The year 2015 was warm and dry, the year 2016 was cooler, but with enough precipitation. The year 2017 was cold with enough precipitation and the year 2018 was warm and humid. The climatic parameters affected a total biomass production in mentioned years. [ABSTRACT FROM AUTHOR]

Climate change and its impact on the environment is an urgent problem of the present time, causing hydrological changes and ecosystem change. As a result, formed ecosystem representing less valuable in economic terms, low productivity. Therefore, study of climate change is an important and urgent task. Global climate changes in the South part of Russia is reflected in the warming of the winter period and an increase in the amount of precipitation during the cold season. This paper analyzes the changes in meteorological conditions in Rostov region and its influence on water regime of the Lower Don. Rostov region is located in the Western subdomain of the Atlantic-continental steppe region, temperate zone. The climate of the region is moderate continental, formed under the influence of air mass transfer from the Atlantic, meridional Northern and southern transfers and transformation of air masses. Flat terrain favors the flow of air masses of different origin. The river flow is formed in the steppe zone. Spring flood depends on soil moisture and moisture reserve in the catchment area. The total water content of the river depends on the amount of winter precipitation and air temperature. The main flow (60 - 65%) formed by meltwater in the spring, 25-30% - through underground supply and 3-5% at the expense of atmospheric precipitation. River is characterized by high and long spring flood. In natural conditions, it accounts for about 70% of annual runoff. Tsimlyanskoe reservoir smoothed seasonal distribution of runoff. Until 1952, spring floods accounted for 78% of runoff and 22% for the rest of the year. After the launch of the reservoir, the situation changed. Only 47% the flow of the river falls in the spring. The rivers of the Don basin are now experiencing a decrease in spring runoff. At the same time, there is an increase in summer, autumn and winter runoff in comparison with the period of climatic norm. Analysis of the annual distribution of runoff led to the allocation of two periods: before the construction of the Tsimlyansk reservoir and after the start of operation. Since 2007, there has been a constant decrease in the water content of the river, which lasted until 2016, the low-water regime. [ABSTRACT FROM AUTHOR]

Last year (2017) was one of the three hottest years on record, with many high-impact events including catastrophic hurricanes and floods, debilitating heat waves and drought. Long-term indicators of climate change continue unabated and arctic sea ice coverage remained below average. Of the hottest years on record, 15 out of 17 have come since 2000. By contrast, more than a century has gone by since the planet had a record cold year (1911). At European level, based on the three different observational records of global average annual near-surface (land and ocean) temperature, 2007-2016 decade was 0.87 to 0.92 °C warmer than the pre-industrial average, which makes it the warmest decade on record. Of the 17 warmest years on record, 16 have occurred since 2000. In Romania, the mean annual air temperature rose by 0,6°C in the last 100 years. The evolution by decades of the mean multiannual air temperature over the 1901-2015 period show that the increasing trend is obvious especially beginning with 1991, 2015 being the warmest year of the records. This paper will make an analysis of 2006 - 2015 decade climate (using temperatures and precipitations records for western part of Romania) using several drought indices. [ABSTRACT FROM AUTHOR]

Smolnik is mining area in Slovakia with very serious impact of mining activities on environment. The mine is known from 13th century by producing of cooper, iron, silver and gold. Mine was closed in 90s of the 20th century. More than 6 milion ton of pyrite ores of various qualities have been abandoned in the mine. The water quality of the Smolnik stream dramatically decreased a short time after the closing of the mine. Smolnik stream is classified as one of more contaminated in Slovakia, especially in sulphates amount and pH values. This is the reason for searching this problem. It is common knowledge that Barium is suitable reagent for sulphate reducing. The paper deals with sulphates removing from model solution using BaCO3 and Ba(OH)2 at various pH values and also sulphates removing from real mine water from old mine Smolnik using the same Ba reagents. Summary of paper describes optimal value pH value and optimal amount of Ba reagent per 1 liter and duration of interaction reagent with water for reaching allowable values of sulphates in the water. [ABSTRACT FROM AUTHOR]

In our paper we deal with the evaluation and comparison of precipitation totals and interception in living and dead climax spruce stands at a research plot of Červenec during the non-vegetation periods (from approximately October to May) in the years 2012 - 2016. The difference in interception was analysed from October 2012 because during the summer 2012 the forests in the area died due to the infestation by the spruce bark beetle (Ips typographus). The research site is located in the Western Tatras (Slovakia) in the area of Sivý vrch at an elevation of 1,420 m a.s.l. Interception was calculated as the difference between the rainfall measured in an open forest area (with a diameter of 1-2 tree heights) and through-fall precipitation. We classified through-fall precipitation into three zones of living and dead stands: canopy gap, dripping zone at the crown periphery and the central zone of the crown near the stem. Tree die-back caused the changes in the precipitation distribution under the canopy. The interception loss in the canopy gap during the monitored period was 15.5% in the living stand and 12.8% in the dead stand, in the dripping zone at the crown periphery it was 14.6% in the living and 10% in the dead stand, and in the central zone of the crown near the stem it was 52.2 in the living and 36.4% in the dead stand. [ABSTRACT FROM AUTHOR]

This paper evaluates the abnormalities in monthly, half-year and annual rainfall totals in the Western Tatras Mts for the period 1994 to 2013, issuing from the values recorded at the precipitation stations Bobrovec situated at 632 m a.s.l., Zuberec at 763 m a.s.l. and Červenec with an elevation of 1,500 m a.s. l. These stations have also different exposures as for the dominant wind flow: Bobrovec is situated on the leeward side, Zuberec on the windward side and Červenec in the summit part of this mountain range. These three stations were chosen to study the influence of exposition and altitude on the precipitation amount and distribution. These precipitation stations do not yet have their precipitation normal (30-year-observation series). Thus the abnormalities of precipitation totals were assessed by comparing our annual sums with long-term average precipitation values calculated based on the monthly sums of vertical precipitation provided by the Slovak Hydrometeorological Institute (stations Bobrovec, Zuberec) and the Institute of Hydrology Slovak Academy of Sciences (station Červenec). At the Zuberec precipitation station, we recorded an average rainfall total of 998 mm, whereas at Bobrovec station of 735 mm. Station Červenec has an average rainfall total of 1471 mm. For each station, the course of percentage difference from the long-term average annual total was represented graphically. [ABSTRACT FROM AUTHOR]

The area of the CSA mine is situated at the northern edge in the central part of the Most Basin (North Bohemia, The Czech republic). The interesting area, currently represented by the internal wastedump and the own openpit mine CSA, has undergone significant changes over time that are associated almost with coal mining activities. This activity hit especially hydrological and hydrogeological conditions of the area. The original surface was naturally drained by the several streams, which were necessary translate to artificial flows due to the developing of coal mining. In the interesting area were located a considerable amount of natural reservoirs, the largest was lake Drinov (Komorany). The presented area is divided into several hydrogeological units, which are characterized by mutually diferent major determinants, such as morphology, lithological charakteristice of the main types of rocks, tectonic disorders etc. The submitted paper describes the changes in the hydrological and hydrogeological conditions in the interesting area that occur during the exploitation of brown coal deposit and their impact on the mining operations in the openpit mine CSA. [ABSTRACT FROM AUTHOR]

CLIMHYDEX project-"Extreme climate and the impact associated to the hydrological events from Romania"--is a Complex Project of Exploratory Research, supported by the Executive Agency for Higher Education, Research, Development and Innovation Funding. The objective of this project is to improve the knowledge on the quantification of the climate change impact on the hydrological and hydrogeological regime in extreme conditions, at river basin scale. In the paper are presented some hydrogeological considerations on the Quaternary deposits and the evolution of hydrostatic levels in correlation with the precipitation in wells that open shallow aquifer from Crisul Alb basin between Varsand and Sebis. This analysis was performed in wells belonging to the Romanian National Hydrogeological Network there is a continuous data from - wells execution date till present. [ABSTRACT FROM AUTHOR]

The occurrence of acid mine drainage is usually associated with mining activities. Acid mine drainage usually due to low pH (3-4) contains high concentrations of sulphates and heavy metals, and because of water pollution and devastation of the country can cause serious environmental problems. Depending on the hydrological characteristics of the region, it may affect a much larger area and can cause the deterioration of the quality parameters of surface and groundwater and the consequent threat to human health. According to Directive 2000/60/EC of the European Parliament it is necessary to ensure adequate water quality and protection of all water sources. In Slovak Republic, as the country with long mining traditions, now exist a few localities with existing acid mine drainage generation conditions (either in form of direct outflow from mine or leachate from tailing ponds). Low pH of these waters is limiting for many various treatment technologies and must be taken into consideration in the research of potential methods for acid mine drainage treatment. The presented paper deals with the utilisation of different substances for sulphates removal from model acidic solutions that imitate the conditions of acid mine drainage. Results of sorption experiments with surface modified silica and also precipitation using barium chloride and Portland cement are presented. [ABSTRACT FROM AUTHOR]

Changes in temperature and precipitation and their impact have been studied worldwide. In this paper, the Black Sea western coast including Bulgarian, Romanian and a partially Ukrainian coastline was considered. The study is focused on the analysis of the trends in annual and seasonal precipitations at a regional scale over 48 yrs (1961-2008). Data sets recorded in 13 weather stations were analyzed: eight Bulgarian stations, 4 Romanian stations and one Ukrainian station. The main goal was to find changes in precipitation using Mann-Kendall and Sen's slope methods. The main findings are: during winter and spring decreasing trends prevails, while during summer and autumn increasing trends are dominant; for annual amounts there is no homogeneous trends, but the slopes in northern part are stronger, whereas seasonal slopes are stronger in the South of the area [ABSTRACT FROM AUTHOR]

Droughts rank first among all natural hazards when measured in terms of the number of people affected. Drought is the most complex but least understood of all natural hazards. It is broadly defined as "severe water shortage". Northern Africa is one of the most arid areas of the world, with rainfalls that vary widely in terms of both temporal and geographical distribution. Libya just like most parts of North Africa is facing drought. Statistical analysis for time series can reveal possible trends in time. For drought risk analysis it is very important to study the historical climate parameters (temperature and precipitation) to know if there is a trend, downward or upward. The aim of this paper is an investigation of the trends by using statistical methods, exactly non-parametric Mann-Kendall test, in these parameters because they have a strong correlation and are related with drought. [ABSTRACT FROM AUTHOR]

The paper presents a method of determining the prognosis of precipitation regime on a certain area and as its application - the ecological planning of agricultural technologies based on this prognosis. The studied area was the vineyard region of Valea Călugărească, for which the data related to precipitation regime were provided since 1936. The utilization of this planning method has led to optimizing the management of agricultural crops on long periods of time and protecting the environment by avoiding the soil compaction, diminishing the high fuel consumption and reducing pollution of noxious emissions. At the same time, the agricultural technologies planning according to precipitation prognosis has led to a harmonized interaction between the agricultural crop and the environment, namely a positive environmental-friendly relationship. [ABSTRACT FROM AUTHOR]

Mining activities for underground and surface extraction of useful minerals generate a change in local hydrostatic levels, requiring the drainage of the resulted water. Owing to water contact with the existing mineralization, mine waters are generally loaded with suspended material and heavy metal ions and have an acid pH. The mine waters continue to be polluting factors for that area and for water courses, even if the mining activity is closed. Therefore is particularly important to study the limitation of polluting effects of mine waters and if possible, the recovery of useful metals from them. The paper goal is to present the characteristics of mine waters from Certej mining area, the suitable techniques for mine water cleaning and finally, some results of a first research stage, applying a method of mine water treatment based on the co-precipitation of heavy metal ions with lime. The research has revealed the conditions in which heavy metal ion content decrease can be realized in order to meet the quality conditions for waters discharged in natural receptors. Except the lead ions (that have the content within the allowed limits) the efficiency of heavy metal ion content reduction was of over 93%, in the determined working conditions. It has been established the requirement for the flocculent dosage and consumption in the precipitate decantation phase and the aeration of clean water, to reduce its alkalinity under the allowed limit (pH=8.5). [ABSTRACT FROM AUTHOR]

Droughts rank first among all natural hazards when measured in terms of the number of people affected. Northern Africa is one of the most arid areas of the world, with rainfalls that vary widely in terms of both temporal and geographical distribution. Libya just like most parts of North Africa is facing drought. Statistical analysis for time series can reveal possible trends in time. For drought risk analysis it is very important to study the historical climate parameters (temperature and precipitation) to know if there is a trend, downward or upward. The aim of this paper is an investigation of the trends by using statistical methods, exactly non-parametric Mann-Kendall test, in these parameters because they have a strong correlation and are related with drought. [ABSTRACT FROM AUTHOR]

Dojran Lake is the smallest natural lake in Macedonia, but is very important water resource for population in the region. Main economy in the region is tourism and fishery. Dojran Lake with its hydrological basin is a closed hydrological system with natural inflow of water to the lake, but no natural outflow. Recharge of the lake is from direct surface and underground inflow. In the period 1988-2000, the water level in the lake continuously was declining. Water level declination caused ecological catastrophe for the flora and fauna in the lake and lake's basin. In 2002, the Republic of Macedonia finished a project to build a system for bringing water from Gjavato wells near Vardar River with capacity of 1 m /s. The water level in the lake has recently increased. The reasons for changing the water level in the lake are not clearly identified, and they are located in hydrological conditions or uncontrolled usage the water from the lake. In order to define the causes of changes in the lake requires detailed hydrological and meteorological analysis. This paper will present the results of mathematical-statistical analysis on the basis of historical data of measured water level, precipitation, and air temperature from hydro-meteorological stationNew Dojran for the period 1961-2008. [ABSTRACT FROM AUTHOR]