- No. 1(7) 2025
«Meteorology. Hydrology. Environmental monitoring»
- 4page
CLIMATIC CHARACTERISTICS OF THERMAL PERIODS IN UKRAINE UNTIL THE END OF THE 21ST CENTURY. PART III: PERIOD OF ACTIVE VEGETATION
Анотація Full version of the article DOI: pp. 4-18
“CLIMATIC CHARACTERISTICS OF THERMAL PERIODS IN UKRAINE UNTIL THE END OF THE 21ST CENTURY. PART III: PERIOD OF ACTIVE VEGETATION
With the ongoing climate change, updated climate scenarios, and higher-resolution Regional Climate Models (RCMs), there is a growing need for a detailed assessment of the duration and changes in start and end dates of thermal periods, which are critical for various economic sectors. Previous studies have analyzed changes in the warm period (when temperatures stay above 0°C) and the growing season (above 5°C). This article is the next part in the series examining shifts in thermal periods across Ukraine till the end of the 21st century, focusing specifically on the Period of Active Vegetation (PAV) which is defined by the persistent transition of daily average temperatures above 10°C and is a key factor in determining suitable conditions for heat-loving crops and plays a crucial role in planning agricultural practices. The goal of this study was to analyze the spatial and temporal characteristics of the PAV and how they are changing over time. Using data from the E-Obs database, we calculated duration, the start and end dates of the PAV across Ukraine for the baseline climate period of 1961-1990 and assessed changes in 1991-2010. Additionally, we estimated future shifts for three periods: 2021-2040, 2041-2060, and 2081-2100, using Representative Concentration Pathways of both moderate (RCP 4.5) and high (RCP 8.5) concentrations. The analysis is based on an ensemble of 34 RCMs from the Euro-CORDEX project, with a spatial resolution of approximately 12×12 km that corresponds to over 7300 grid nodes in Ukraine. In period 1991-2010, the duration of the PAV in Ukraine increased compared to 1961-1990, particularly in the northwest, where it extended by at least 10 days. By 2021-2040, under RCP 4.5, the PAV is expected to lengthen by about 7 days across most of Ukraine and by 7-14 days in the steppe regions of Crimea, southern Odesa Oblast, and the Carpathians. Under RCP 8.5, the increase is projected to be mostly 7-14 days, with the Carpathians seeing an increase of 14-21 days, and up to 7 days in Dnipropetrovsk Oblast. By 2041-2060, under RCP 8.5, the PAV is expected to increase significantly—by an average of 14-21 days, and up to 30 days in western Ukraine, Crimea, and southern Odesa Oblast. In 2081-2100, under RCP 4.5, the duration of the PAV in Ukraine is projected to resemble that of the RCP 8.5 scenario for 2041-2060. Under RCP 8.5, the extension of this period relative to 1991-2010 could range from 31 to 70 days, with the most pronounced increases occurring from east to west. Increasing the duration of the growing season and PAV can strengthen the agroclimatic potential of Ukraine in the future and will contribute to obtaining higher crop yields, if plants will be provided with moisture, that is, the timely implementation of modern methods of adaptation to changes in hydrothermal conditions and other agrotechnologies for plant protection.
- 19page
AGROCLIMATIC ASSESSMENT OF LAND BIOLOGICAL PRODUCTIVITY OF THE DNIPROPETROVSK REGION IN THE CONDITIONS OF CLIMATE CHANGE
Анотація Full version of the article DOI: pp. 19-27
“AGROCLIMATIC ASSESSMENT OF LAND BIOLOGICAL PRODUCTIVITY OF THE DNIPROPETROVSK REGION IN THE CONDITIONS OF CLIMATE CHANGE
The article considers the bioclimatic potential of the Dnipropetrovsk region in the context of modern climate change. Based on the physical and statistical model of D.I. Shashko, the bioclimatic potential (BCP) of the region for average long-term conditions (“base period”) is determined according to the Agroclimatic Handbook for the Dnipropetrovsk region: 1986-2005. A comparative analysis of its changes in the future (2021-2050) is presented in comparison with the baseline according to the climate scenarios of the representative concentration trajectory (Representative Concentration Pathways – RCP4.5 (medium) and RCP8.5 (hard). The studies have established that a significant decrease in the amount of precipitation in the warm period of the year and an increase in the cold period are expected, which will cause a decrease in the moisture index of Shashko and in the region for the period until 2050, arid and dry moisture conditions are expected against the background of the sums of temperatures for the warm period, close to the “base period” under the conditions of the implementation of these scenarios. The obtained BCP values in the “base period” characterize the average and moderately high conditions of the biological productivity of the climate. Under conditions of optimal moisture, the bioclimatic potential increases and characterizes the increased biological productivity of the climate. Under the implementation of the scenarios of the RSP family in both cases, a decrease in BCP is expected by 2050 Dnipropetrovsk region by 12-26% (under the RCP 4.5 scenario) and 17-34% (under the RCP 8.5 scenario) compared to the “base period” and will correspond to a reduced and very low biological productivity of the climate. Under conditions of optimal moisture, the bioclimatic potential also decreases. An assessment of the quality scores was obtained taking into account the type of main agricultural crops (cereals, sunflower, sugar beet) in the region both for the “base period” and under the conditions of the implementation of the RCP family of scenarios. In the “base period”, the highest quality score will be sunflower (145 points), followed by cereals (116 points) and in third place sugar beet - 66 points. It was established that under the conditions of the implementation of the RCP family of scenarios, a decrease in the number of points is expected by 2050, but the trend of their distribution by crops remains. Due to the increasing aridity of the region's climate, it is recommended to introduce drought-resistant varieties for sunflower and grain crops and irrigation during the critical growing season, especially for sugar beets, to increase productivity.
- 28page
NUTRIENT LOAD IN THE SULA RIVER BASIN AND MEASURES TO MITIGATE ITS EFFECTS
Анотація Full version of the article DOI: pp. 28-42
“NUTRIENT LOAD IN THE SULA RIVER BASIN AND MEASURES TO MITIGATE ITS EFFECTS
Nitrogen and phosphorus enter water bodies from point and diffuse sources. In the practice of water resources management in Ukraine, attention has so far been paid primarily to point sources, whereas the role of diffuse sources has long been ignored by researchers. To take into account the role of diffuse sources, modelling approaches are used worldwide. Therefore, the paper presents the calculation of the nutrient load of the Sula basin by two different methods - the mass balance method and the MONERIS model. According to the mass balance method, the emission in the Sula catchment is 921.2 t · year-1 for nitrogen and 312.9 t · year-1 for phosphorus. According to the MONERIS model, the total nitrogen emission is 1,809.8 t · year-1, and the phosphorus emission is 196.2 t · year-1. Based on the calculations, effective tools for reducing the anthropogenic load on the Sula catchment were proposed, in particular the implementation the Nitrate Directive at the national and regional levels, the conduction an environmentally oriented dialogue between state institutions, local governments, water users and farmers. It was also proposed to create a unified hierarchical system for collecting qualitative and operational information on the environmental situation within the catchment basins, as well as to establish a system for measuring chemical nitrogen and phosphorus flows at all eight gauging stations within the Sula basin. Specific measures to reduce the anthropogenic load in the Sula catchment include: improving the quality of sewage systems; reducing the use of fertilisers; reducing the share of arable land by converting it to pasture and forest; implementing organic farming; establisihing coastal protection stripes and strictly enforcing them; and restoring natural wetlands and natural river channels. The MONERIS model has shown that the greatest reduction in nitrogen and phosphorus emissions is possible through the use of contour ploughing and intercropping.
- 43page
SOLVING HYDROGEOLOGICAL PROBLEMS IN THE CONTEXT OF ASSESSING RESOURCE LOSSES AND THE FEASIBILITY OF RESTORATION OF THE KAKHOVKA RESERVOIR
Анотація Full version of the article DOI: pp. 43-58
“SOLVING HYDROGEOLOGICAL PROBLEMS IN THE CONTEXT OF ASSESSING RESOURCE LOSSES AND THE FEASIBILITY OF RESTORATION OF THE KAKHOVKA RESERVOIR
The contradictory modern perspectives on the significance and role of the Kakhovka Reservoir in various sectors of Ukraine and the natural ecosystem necessitate the development of a systematic approach for a comprehensive assessment of the feasibility/infeasibility of its restoration. The general algorithm for such an approach may consist of sequential processing of the following stages: 1) comprehensive evaluation of long-term consequences and problems caused by the destruction of the reservoir dam (without assessing the relatively temporary consequences of the catastrophe itself); 2) assessment of the possibility of overcoming all problems that have arisen without restoring the reservoir and development of appropriate measures to address them; 3) comparison of the costs of these measures with the costs of restoring the reservoir and subsequent mitigation of negative effects from its existence; 4) objective comprehensive conclusion regarding the feasibility of reservoir restoration. The article also discusses hydrogeological assessments of filtration losses during reservoir filling and the depletion of artificial groundwater reserves after water discharge. The rates of backwater propagation (1956-1975) and groundwater runoff from the flood zone after the war crime committed by the occupiers in 2023 are compared. It is emphasized that reservoirs, especially large ones, are important factors in replenishing fresh groundwater resources and creating their artificial storage, as former local and sometimes regional groundwater discharge area transform into recharge areas. General features of formation and approaches to calculations of groundwater balance in reservoir influence zones are examined, as well as important specific features of hydrogeological conditions in the territory adjacent to the lower Dnipro.
- 59page
HYDROGRAPHY AND WATER RESOURCES OF MOLDOVA: CONDITION, USE, MANAGEMENT
Анотація Full version of the article DOI: pp. 59-70
“HYDROGRAPHY AND WATER RESOURCES OF MOLDOVA: CONDITION, USE, MANAGEMENT
Ukraine and the Republic of Moldova have not only common state borders, but also common cross-border river basins. In addition, the countries share common European integration aspirations (in 2022, they became candidate countries for EU membership). Therefore, the mutual interest in many spheres of activity in each of the countries is quite understandable. The article examines the hydrographic conditions and features of the hydrographic zoning of the territory of Moldova in accordance with the provisions of the EU Water Framework Directive, the volume of the country's water resources, their use, and the institutional structure of their management. There are 3621 watercourses in the country with a total length of about 16 thousand. km Among them, 250 rivers have a length of more than 10 km each. A total of 9 of them are over 100 km long. The most important rivers that form the surface water resources of Moldova are the transboundary Dniester and Prut. In 2017 the Agreement between the Cabinet of Ministers of Ukraine and the Government of the Republic of Moldova on cooperation in the field of protection and sustainable development of the Dniester River basin was signed. In the hydrographic zoning of the territory of Moldova, carried out in accordance with the requirements of the EU Water Framework Directive in 2011, two district of river basins were allocated for management in the territory of Moldova: 1) Danube-Prut and Black Sea; 2) Dniester. According to Aquastat FAO, the average annual volume of total water resources in Moldova is 12.27 km3/year, of which 13% are internal water resources (1.32 km3/year), and 87% are external water resources (10.65 km3/year year). With the population in 2024 3 million 035 thousand people, the indicator of total water resources per 1 person is 4043 m3/year, internal water resources per 1 person is 534 m3/year. The country has a very high coefficient of external dependence – 0.87. A modern institutional structure of water resources management has been created. The Ministry of the Environment of the Republic of Moldova formulates water policy and coordinates and controls the activities of management bodies and subordinate state services and institutions and enterprises of which it is the founder, in particular: the Environmental Protection Agency, the National Administration 'Water of Moldova', the State Hydrometeorological Service, state enterprise 'Hydrogeological Expedition'. By resolution of the Government of the Republic of Moldova in 2017 the management plan of the Dniester district of the river basin was approved in 2018. – the management plan for the Danube-Prut and Black Sea district of the river basin.
- 71page
SIMULATION OF RAIN FLOODS OF THE STRYI RIVER BY AN ARTIFICIAL NEURAL NETWORK
Анотація Full version of the article DOI: pp. 71-78
“SIMULATION OF RAIN FLOODS OF THE STRYI RIVER BY AN ARTIFICIAL NEURAL NETWORK
Timely forecasting of rain floods on rivers allows you to avoid the negative consequences that they can cause by destroying structures and communications located in their channels or on floodplains. It is relevant for the Stryi River, as catastrophic rain floods occur in its basin from time to time. The article is devoted to the use of an artificial neural network (ANN) for modeling the rain runoff of the Stryi River near the Verkhnie Synyovydne village for the period 2005-2012. Using the 'nnet' package in RStudio (version 2024.12.0 Build 467), a direct-connection ANN model was developed. In addition, the classical linear multiple regression model (CLMRM) was also used. The model based on ANN has an advantage over the CLMRM, as its statistical indicators of modeling quality are higher. Thus, the Nash-Sutcliffe efficiency coefficient of the ANN model for the training sample was 91.6%, and for the test sample was 92.5%, which classifies it as excellent. However, for CLMRM these indicators were 81.5% and 89.4%, respectively. Graphical analysis also demonstrated the advantage of the ANN model, since it was for it that a better match between the simulated and historical values was obtained, which is confirmed by higher of determination coefficients (0.92 ANN and 0.82 CLMRM for the training sample and 0.93 ANN and 0.89 CLMRM for the test sample). The statistic indicators RMSE of the CLMRM model turned out to be greater than the ANN model for both the training (29.8 m3/s and 20.1 m3/s) and test (25.2 m3/s and 21.1 m3/s) samples. The advantage of the ANN model over the CLMRM model is that it takes into account the nonlinearity of 'rainfall-runoff' relationship due to the parallelism of its architecture. In Ukraine, river flow modeling by ANNs was caried out for the first time. This approach may be particularly relevant for transboundary rivers of the country, for which there are significant problems with the availability of observation data.
- 71page
RADIATION STATE OF THE EXCLUSION ZONE OF 2024 IN ACCORDANCE WITH THE RESULTS OF RADIATION ENVIRONMENTAL MONITORING
Анотація Full version of the article DOI: pp. 71-78
“RADIATION STATE OF THE EXCLUSION ZONE OF 2024 IN ACCORDANCE WITH THE RESULTS OF RADIATION ENVIRONMENTAL MONITORING
The article presents results of radiation and environmental monitoring in the Exclusion Zone for the year 2024. According to the results of radiation and environmental monitoring in the Exclusion Zone in 2024, important analytical data were obtained: maximum power values of the ambient dose equivalent of gamma radiation are characteristic of the territories in the northern and western 'trace' of radioactive fallout; radiation state of the Exclusion Zone air environment and its dynamics during 2024 were determined by the nature of surface contamination of the territory, сontrol levels exceeding activity in the air was recorded; surface waters remain an important route of radionuclide removal beyond the Exclusion Zone; radiation state of underground waters, radionuclide contamination of eocene and cenomanian-lower cretaceous water-bearing complexes; monitoring results at landscape landfills; radiation survey results of unauthorized residence places of the population in the Exclusion Zone. In May 2024, a 2-fold excess of the control levels of bulk activity of 137Cs was recorded in the surface layer of the atmosphere of the city of Chornobyl, a place of prolonged stay of personnel. Surface waters remain the main route of radionuclides removal outside the WZ. The water removal of 90Sr by the Pryp’yat’ River in the Chornobyl zone in 2024 was 1.3 times less than the removal in 2023 and 1.6 times greater than the average value for the last 5 years. The main reserves of activity are concentrated in the Temporary radioactive waste storage points “Budbaza” and “Red forest”, which are located along the western trace of the Chernobyl emission. In some areas of the right-bank floodplain of the Pripyat River, the so-called “distributed” sources of radionuclide migration begin to play a decisive role in shaping the removal of 90Sr by groundwater into the Pryp’yat’ River.
- 98page
RECOGNITION OF HYDROGEOLOGICAL DROUGHTS BY SPI AND SGI INDICES IN THE SOUTHERN BUG RIVER BASIN
Анотація Full version of the article DOI: pp. 98-112
“RECOGNITION OF HYDROGEOLOGICAL DROUGHTS BY SPI AND SGI INDICES IN THE SOUTHERN BUG RIVER BASIN
It is obvious that hydrogeological drought is caused by meteorological drought and is caused by a decrease in groundwater recharge and an increase in its flow. However, it remains unclear which factor is more influential: rising air temperatures, decreased precipitation, declining river stages, or other related variables. The article highlights a method for identifying hydrogeological drought based on the analysis of SGI indices and confirmation of meteorological drought. Based on retrospective data, the duration of meteorological droughts was assessed to determine whether it was sufficient to trigger significant and prolonged recession in groundwater levels. Groundwater level depths affected by meteorological drought were also analyzed. Spatial and temporal patterns of drought manifestation were identified, along with the degree of inertia in groundwater level response to climatic changes and meteorological phenomena. The analysis was conducted using data from hydrogeological monitoring wells in the Southern Bug River Basin, by calculating and comparing the Standardized Precipitation Index (SPI) and the Standardized Groundwater Index (SGI). A series of SPI and SGI maps for the year 2016 was developed using the spline interpolation method in the ArcMap environment. Additionally, the long-term dynamics of SGI over the 1980–2020 period were analyzed using data from nine monitoring wells. The results showed spatial correlation between the indices, but with a temporal lag: the most intense meteorological drought was recorded in July–September, while the greatest groundwater level decline was observed in August–October. The analysis allowed the identification of the most drought-prone regions in the central part of the basin and substantiated the feasibility of combining SPI and SGI indices for comprehensive water resource monitoring. The proposed approach can serve as a foundation for the development of a regional early warning system for groundwater droughts and adaptive groundwater management under climate change conditions.
