Hydrometeorological Observations Research Articles

Comparative analysis of satellite and reanalysis data with ground‐based observations in Northern Ghana

AbstractAccurate predictions of streamflow and flood events are contingent upon the availability of reliable hydrometeorological data. In regions characterized by scarcity of ground‐based hydrometeorological observations, satellite and reanalysis data assume prominence as alternative predictors. Floods and droughts have emerged as a significant concern in Northern Ghana, yet the scarcity of ground‐based hydrometeorological data impedes effective prediction of these hydrological events. Consequently, the identification of suitable surrogate hydrometeorological data holds paramount importance in addressing these challenges. This study, therefore, assessed the accuracy of satellite and reanalysis data against ground‐based data in Northern Ghana. Rainfall and mean temperature spanning from 1998 to 2019 and soil moisture datasets from 2019 to 2022 were collected from GMet, ISMN (ground‐based), CHIRPS, PERSIANN‐CDR, ERA5, ARC2, MERRA‐2, TRMM and CFSR (satellite and reanalysis). Employing rigorous statistical measures, namely standard deviation, mean absolute error (MAE) and mean bias error (MBE), the accuracy of these datasets was thoroughly evaluated. The results revealed that CHIRPS and PERSIANN‐CDR exhibited superior accuracy in rainfall simulation, with CHIRPS demonstrating particularly consistent congruence with observed data. In terms of mean temperature prediction, ERA5 surpassed MERRA‐2 and CFSR. Regarding soil moisture assessments, both ERA5 and CFSR offered satisfactory simulations. Hence, our findings advocate for the preference of CHIRPS (for rainfall data), ERA5 (for temperature data) and a combination of CFSR/ERA5 (for soil moisture data) as dependable primary data sources for streamflow modelling, drought analysis, flood prediction and water resource management in the context of Northern Ghana.

Влияние основных показателей теплообеспеченности на сельское хозяйство Саратовской области

An analysis of changes in surface air temperature was carried out at stations in the Saratov region from 2002 to 2022. The study is based on the analysis of materials from longterm hydrometeorological observations carried out through the Roshydromet network, which reflects the reliability of the results obtained. The article presents a comparison of average monthly temperatures for a given period with temperature norms. A map of temperature changes was constructed. The duration of the growing season for plants was calculated and analyzed. With the help of agroclimatic zoning of the country according to D. I. Shashko there was established which zone the Saratov region belongs to and which agricultural crops are best cultivated in the region.

Долгосрочная оценка режима минимального зимнего стока рек бассейна озера Севан при изменении климата

Introduction. Analysis and assessment of the statistically significant consequences of climate change for the long-term minimum 30-day winter runoff of rivers in the Lake Sevan basin is of significant interest to consumers and water resource management, being an important hydrological issue. The relevance of consideration of the issue is due to the fact that for Armenia Lake Sevan is a strategic reservoir of fresh water, a large water management complex, a source of water for hydropower and agricultural irrigation, an object of tourism and recreation. Issues of formation and calculation of the minimum runoff of rivers in the lake basin. Sevan were discussed in works, the analysis of the spatial-temporal distribution of the winter minimum decade-day, monthly and 30-day runoff can be found, for example, in works.In contrast to the listed works, in this study a technique for assessing the statistically significant consequences of climate change for the hydrological regime in relation to small foothill watersheds of the rivers of the Lake Sevan basin (Republic of Armenia) is considered. The values of the minimum 30-day water runoff within the study area can be used when calculating standards for permissible discharges into rivers, to assess natural groundwater resources, as indicators of the extremeness of river flow and in other water management calculations. Research methods and materials. The methodology is based on a probabilistic model of the formation of long-term river runoff, which is approximated by a system of linear equations for the initial statistical moments. As the source material were used the data of actual hydrometeorological observations (minimum 30-day winter river runoff, air temperature and precipitation) of the “Center for Hydrometeorology and Monitoring” of the SNCO of the Ministry of Environment of the Republic of Armenia. Research results. The results of approbation of the methodology on retrospective material are presented, taking into account possible climate change both towards warming and towards cooling.The conditions for the applicability of the methodology to small foothill watersheds for assessing the minimum 30-water winter river runoff are identified. The obtained satisfactory results made it possible to assess the impact of climate change for the minimum runoff using the IPCC climate scenarios. Three climatic scenarios are considered, the model of the Max Planck Institute with a monthly time resolution. Conclusions. As a result, watersheds of rivers in the basin of Lake Sevan were identified, in which significant deviations of the predicted average annual values of the minimum 30-day winter runoff and the coefficients of its variation from the actual ones in the implementation of the considered scenarios can be expected. An analysis of the obtained results is given from the point of view of taking possible preventive measures, including strategic planning of the use of water resources in winter low water, in case of climate change.

Climate change and consequences of climate change in Kazakhstan

The article examines the impact of climate change on the territory of Kazakhstan and its consequences for ecosystems, agriculture, economy and public health. Thecurrent climate change trends in Kazakhstan were analyzed using data from hydrometeorological observations at stations and posts of the state observation network of RSE «Kazhydromet». Climate norms and variable anomalies are considered, and changes in climate characteristics for the period 1976-2022 are estimated using linear trend coefficients and the coefficient of determination. The author focuses on the analysis of current climate change trends in the region and possible strategies for adaptation to them.

Understanding hydrological processes of glacierized catchments in the western Himalayas by a multi‐year tracer‐based hydrograph separation analysis

AbstractSnow and glacier melt are significant contributors to streamflow in Himalayan catchments, and their increasing contributions serve as key indicators of climate change. Consequently, the quantification of these streamflow components holds significant importance for effective water resource management. In this study, we utilized the spatio‐temporal variability of isotopic signatures in stream water, rainfall, winter fresh snow, snowpack, glaciers, springs, and wells, in conjunction with hydrometeorological observations and Snow Cover Area (SCA) data, to identify water sources and develop a conceptual understanding of streamflow dynamics in three catchments (Lidder, Sindh, and Vishow) within the western Himalayas. The following results were obtained: (a) endmember contributions to the streamflow exhibit significant spatial and seasonal variability across the three catchments during 2018–2020; (b) snowmelt dominates streamflow, with average contributions across the entire catchment varying: 59% ± 9%, 55% ± 4%, 56% ± 6%, and 55% ± 9% in Lidder, 43% ± 6%, 38% ± 6%, 32% ± 4%, and 33% ± 5% in Sindh and 45% ± 8%, 40% ± 6%, 39% ± 6%, and 32% ± 5% in Vishow during spring, summer, autumn, and winter seasons, respectively; (c) glacier melt contributions can reach ~30% to streamflow near the source regions during peak summer; (d) The primary uncertainties in streamflow components are attributed to the spatiotemporal variability of tracer signatures of winter fresh snow/snowpack (±1.9% to ±20%); (e)regarding future streamflow components, if the glacier contribution were to disappear completely, the annual average streamflow in Lidder and Sindh could decrease up to ~20%. The depletion of the cryosphere in the region has led to a rapid increase in runoff (1980–1900), but it has also resulted in a significant streamflow reduction due to glacier mass loss and changes in peak streamflow over the past three decades (1990–2020). The findings highlight the significance of environmental isotope analysis, which provides insights into water resources and offers a critical indication of the streamflow response to glacier loss under a changing climate.

Parameters of the temperature optimum for cyanobacteria in the Kuibyshev reservoir

Based on the results of hydrometeorological observations in the period 2016-2021, the parameters of the optimum temperature zone (TTO) for the process of mass development of cyanobacteria in the Kuibyshev reservoir were determined. Such parameters of the optimum zone as duration, intensity, upper and lower boundaries depend on the hydrometeorological conditions of a particular year. For the period 2016-2021, the average duration of the OST was 44 days, the longest - 72 days and was observed in 2021, and the shortest - 11 days and was observed in 2019. The highest intensity of OST was observed in 2021, when 10 days were characterized by low intensity, 15 days by moderate intensity, 23 days by strong intensity, 24 days by very strong intensity and 7 days by extreme intensity. The lowest intensity was observed in 2019, when 10 days were characterized by low intensity and 1 day by high intensity. The upper border of the WTO in 2021 was observed on June 21, and the lower border on September 1. In 2019, the upper limit was observed on June 23, and the lower limit on July 26. For the process of mass development of cyanobacteria, the most favorable year is 2021, and the unfavorable year is 2019. It was found that with the increase in air and water temperature, the duration and degree of intensity of the temperature optimum zone increased. Consequently, with a further increase in air temperature due to global warming, the duration and intensity of the optimum temperature zone will only increase, which will activate the process of mass development of cyanobacteria, which will negatively affect the ecological state and water quality of the Kuibyshev reservoir.

Can atmospheric reanalysis datasets reproduce flood inundation at regional scales? A systematic analysis with ERA5 over Mahanadi River Basin, India.

The prime challenges limiting efficient flood management, especially over large regions, are concurrently related to limited hydro-meteorological observations and exorbitant economics with computational modeling. Reanalysis datasets are a valuable alternative, as they furnish relevant variables at high spatiotemporal resolutions. In recent times, ERA5 has gained significant recognition for its applications in hydrological modeling; however, its efficacy at the inundation scale needs to be understood. The advent of "global flood models" has ensured flood inundation and hazard modeling over large regions, otherwise obscure with regional models. For the first time, the present study explores the fidelity of ERA5 reanalysis at the inundation scale over the Mahanadi River basin, a severely flood-prone region in India. The biases in the discharges within ERA5 are ascertained by comparing them with station-level data at the nascent and extreme levels (i.e., 95th and 99th percentiles). Later, ERA5 is fed to LISFLOOD-FP, an acclaimed global flood model, to reenact the 2006, 2008, 2011, and 2014 flood events. Hit rates exceeding 0.8 compared to MODIS satellite imageries affirm the suitability of ERA5 in accurately capturing flood inundation. Distributed design discharges for 50yr and 100yr are derived using a set of extreme value distributions and fed to LISFLOOD-FP to derive design flood inundation and hazards in terms of both "depth" and "product of depth and velocity" of flood waters. Results derived from the study provide vital lessons for efficient land-use planning and adaptation strategies linked to flood protection and resilience.

Sowing time of winter crops in Belarus and recommendation for optimization in conditions of modern climate change

Assessment of agroclimate conditions of the autumn period on the territory of Belarus under the conditions of modern climate change with the distribution of cumulative temperatures during autumn period for 2000–2020 is presented. The results of analysis of estimates of moisture indicators for the autumn period (precipitation amounts, Selyaninov’s hydrothermal moisture coefficient, and productive moisture reserves in the arable soil layer of 0–20 cm) are provided. Based on literary sources, recent research by Belarusian scientists, data from observation points of the state hydrometeorological network for the phases of development of winter crops (wheat, triticale, rye) in autumn, results of studies on tillering of winter crops depending on the sowing time and weather conditions in the autumn period, an analysis was carried out and criteria for cumulative temperatures were clarified to calculate the optimal sowing time for winter crops on the territory of Belarus. The optimal time for sowing winter grain crops has been calculated for administrative regions and points of the state network of hydrometeorological observations, taking into account the predicted air temperature for September. Recommendations are given for calculating the optimal sowing time for winter crops for points with no hydrometeorological observations, as well as with possible consideration of soil types and field location.

Contemporary and ancient environmental conditions in the area of the AARI meteorological station Khastyr on Khatanga Bay on Hara-Tumus Peninsular

The aim of the article is to characterize the current and ancient environmental conditions in the area around a new AARI meteorological station, located in the west of the Khara-Tumus Peninsula (73° 49' 39,5'' N 109° 39' 13,5'' E) on the Khatanga Bay of the Laptev Sea. The Khastyr meteorological station was organized in 2016, and for the moment a 6-year (2017–2022) series of hydrometeorological observations has been performed. The average annual temperature at the station is –11.7 °C. The maximum temperature is 31.8 °C, the minimum temperature is –47.3 °C. The annual amount of atmospheric precipitation is 238 mm. The wind blows from west to east or from east to west during most of the year. The maximum wind speed is 28 m/sec, the average wind speed is 5,4 m/sec. The ice cover in the Khatanga Bay disappears in the second part of July and forms again in September-October. The winter lasts here for 9 months of the year.The geological, geomorphological and permafrost structure along the shoreline near the station is investigated.The cliff consists of marine sediments of the Middle and Late Pleistocene. The IR-OSL dating of the sands from the cliff’s basement shows that the sediments are 206 000 year old. The marine sediments, including Karginsky deposits with wood and amber, dated by the radiocarbon method and shown to be 42 000 year old (45 000 calendar year old), are covered by Ice Complex sediments, the mammal bones from which have a radiocarbon age of 32 thousand years (36 thousand calendar years). The saiga (Saiga tatarica) bones found near the Taimyr Peninsula for the first time have a radiocarbon age of 17 thousand 14C years (22 thousand calendar years).Permafrost processes are very active in this area of typical tundra. Therefore, a testing plot for investigating permafrost processes was organized on the territory of the station. Also, this place is very convenient for investigating coastal erosion processes. The Khastyr station can be used as a point for organizing complex studies of the natural environment in a typical tundra on the shore of Khatanga Bay.

Nonparametric Bayesian Networks as a Tool of Multiscale Time Series Analysis and Remote Sensing Data Integration

Introduction. Nonparametric Bayesian networks are a promising tool for analyzing, visualizing, interpreting and predicting the structural and dynamic characteristics of complex systems. Modern interdisciplinary research involves the complex processing of heterogeneous data obtained using sensors of various physical nature. In the study of the forest fund, both methods of direct dendrological measurements and methods of remote observation using unmanned aerial vehicles are widely used. Information obtained using these methods must be analyzed in conjunction with hydrometeorological monitoring data.Aim. Investigation of the possibility of automating the monitoring of the well-being of the forest fund based on the integration of ground survey data, remote multispectral measurements and hydrometeorological observations using the mathematical apparatus of nonparametric Bayesian networks.Materials and methods. To assess the long-term joint dynamics of natural and climatic indicators and the radial growth of trees, a modified method of multiscale cross-correlation analysis was used with the removal of the background trend described by the moving average model. Relationships between various indicators were estimated based on the unconditional and conditional nonparametric Spearman correlation coefficients, which were used to reconstruct and parameterize the nonparametric Bayesian network.Results. A multiscale nonparametric Bayesian network was constructed to characterize both unconditional and conditional statistical relationships between parameters obtained from remote sensing, hydroclimatic and dendrological measurements. The proposed model showed a good quality of the plant fund state forecasting. The correlation coefficients between the observed and predicted indicators exceed 0.6, with the correlation coefficient comprising 0.77 when predicting the growth trend of annual tree rings.Conclusion. The proposed nonparametric Bayesian network model reflects the relationship between various factors that affect the forest ecosystem. The Bayesian network can be used to assess risks and improve environmental management planning.

Hydrometeorological observations from the Upper Kentucky headwaters flash floods, 26–29 July 2022

Abstract Online OnlyIn late July 2022, heavy rains resulted in localised flash flooding across the Upper Kentucky River. To quantify the scale of this event, we analysed hydrometeorological activity using radar, precipitation and stream gauge data for three unregulated watersheds within the headwater forks of the Kentucky River Basin. The July 2022 event resulted from warm‐season elevated thunderstorm activity generating record flooding for the Whitesburg branch of the headwaters. Steeper topography and barren surface cover may have also influenced flooding on a local scale. A better understanding of local flood responses may mitigate future impacts of these events.

ANALYSIS OF FACTORS FOR FORMATION OF THE CHUMYSH RIVER MAXIMUM RUNOFF (WESTERN SIBERIA)

Link for citation: Samoilova S.Yu., Lovtskaya O.V., Kudishin A.V., Arnaut D.V. Analysis of factors for formation of the Chumysh river maximum runoff (Western Siberia). Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 5, рр.116-128. In Rus. The relevance of the study stems from the necessity to refine the methods of medium-term flood forecasts when sufficient hydrometeorological data are not available. The purpose of the work is to assess probable application of spatially distributed precipitation models to forecast runoff volume of flood, to develop stochastic models for predicting flood volume and its maximum discharge using hydrometeorological observation data, distributed precipitation datasets from reanalysis and remote sensing data of high spatial and temporal resolution. Methods include geoinformation, complex geographical and hydrometeorological analysis, statistical methods (correlation and regression analysis). Results. The Chumysh basin moistening was estimated due to the data from spatially distributed precipitation models and hydrometeorological observation data; the relationship of total precipitation with runoff volume and maximum flood discharge was analyzed. A comparative evaluation of the obtained dependencies made it possible to identify key predictors for deriving the multiple linear regression equation. The statistical model was developed for predicting volumes and maximum discharges of Chumysh flood at Talmenka settlement using hydrometeorological observation data and reanalysis ones of high spatial and temporal resolution.

Features of Formation of the Lena Polynya on the Estuarine Coast of the Bykovsky Arm in the Summer

Based on the results of the global oceanic reanalysis (GLORYS12.v.1), materials of hydrometeorological observations of the Roshydromet network in the Laptev Sea and the mouth of the Lena River, reviews of the ice processes in the Arctic Ocean by the Arctic and Antarctic Research Institute, this paper considers the features of the evolution of the Lena Polynya on the estuarine coast of the Bykovsky Arm in the warm period 1993–2019. The relationship between the timing of the formation of a polynya on the seashore of this arm with the dates of the beginning of the flood at the top of the Lena River delta has been revealed. The assumption is confirmed that the average growth rate of the Lena polynya in summer is determined by the timing of its formation – the earlier the flood begins, the earlier the polynya forms on the coast of the Bykovsky arm and the smaller the average rate its growth. It has been established that the process of warming in the mouth area of the Lena in 2008–2019 stabilized, as there are no significant trends in the characteristics of water and ice regimes. These regularities may be invariant for other mouths of the rivers of the Laptev Sea basin, and the obtained dependences can be used to improve the forecast of the dates of cleansing of the water area at the estuary seashore of the Lena from ice and planning icebreaking navigation along the route Tiksi port–Lena River.

Exploring the impacts of climate change and human activities on future runoff variations at the seasonal scale

Most watersheds around the world have been changing their natural flow patterns because of the coupled effects of climate change and human activities. Understanding the quantitative impacts of projected climate and human factors on future runoff variations is essential for adaptability assessment of water resource management, especially at the seasonal scale where their intra-annual changes are detected. In this study, an extended Budyko framework that combines traditional elasticity and decomposition methods is developed to analyze future seasonal runoff variations. The upper reach of the Hanjiang River basin (UHRB) in China is used as a case study. The case results are quantified and compared with the monthly ABCD model using historical hydrometeorological observations over 1961–2020 and near-future climate projections over 2031–2060 from the multi-model ensemble of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP3b). We find that: (1) human activities including the operation of the Han-to-Wei inter-basin water transfer (IBWT) and reforestation projects have a substantial negative impact on runoff reduction in this region, accounting for a proportion of ∼70% in energy-limited seasons and ∼65% in water-limited seasons; and (2) the role of climate change projected by ISIMIP3b will intensify in energy-limited seasons, especially under the high-emission scenario with the increasing trend of effective precipitation,. Additionally, the performance of our extended Budyko framework is sufficiently robust to parameter disturbance experiments, indicating its applicability as an alternative for exploring future seasonal runoff variations.

ОПЫТ ПРИМЕНЕНИЯ КОНЦЕПТУАЛЬНОЙ МОДЕЛИ GR4J ДЛЯ РАСЧЕТА СТОКА РЕК БАССЕЙНА УССУРИ

The open-source low-parametric conceptual hydrological model GR4J was used for runoff simulations of 17 nested catchments of the Upper Ussuri River basin with areas ranging from 133 to 24400 km2, including the Kirovskii outlet. The data of standard hydrometeorological observations of Primorye Administration for Hydrometeorology and Environmental Monitoring were used for the model calibration and verification. Runoff simulations were performed with a daily step. The criteria commonly used in hydrological community, namely, the Nash-Sutcliffe model efficiency coefficient (NSE), coefficient of determination ( R 2), and bias (BIAS) were used to assess the modeling efficiency. According to the specified criteria, modeling results are mostly in “satisfactory” or better categories. The base of the unit hydrograph expectedly increases with the catchment area, but there were no other relationships found between the values of calibrated model parameters, the annual water content, and the main morphometric parameters of the catchments. It was shown for the studied catchments that the stabilization and the maxima of the modeling efficiency scores are reached at the catchment areas of 1200-1700 km2. The influence of representativeness of the weather station network on the modeling efficiency was demonstrated using complementary meteorological observations from experimental catchments in the Upper Ussuri basin for the simulation of the catastrophic flood in 2016 that was caused by typhoon Lionrock.

ЗОНА ТЕМПЕРАТУРНОГО ОПТИМУМА ЦИАНОБАКТЕРИЙ В КУЙБЫШЕВСКОМ ВОДОХРАНИЛИЩЕ

Based on the results of hydrometeorological observations in the period 2016-2021, the parameters of the optimum temperature zone (TTO) for the process of mass development of cyanobacteria in the Kuibyshev reservoir were determined. Such parameters of the optimum zone as duration, intensity, upper and lower boundaries depend on the hydrometeorological conditions of a particular year. For the period 2016-2021, the average duration of the OST was 44 days, the longest - 72 days and was observed in 2021, and the shortest - 11 days and was observed in 2019. The highest intensity of OST was observed in 2021, when 10 days were characterized by low intensity, 15 days by moderate intensity, 23 days by strong intensity, 24 days by very strong intensity and 7 days by extreme intensity. The lowest intensity was observed in 2019, when 10 days were characterized by low intensity and 1 day by high intensity. The upper border of the WTO in 2021 was observed on June 21, and the lower border on September 1. In 2019, the upper limit was observed on June 23, and the lower limit on July 26. For the process of mass development of cyanobacteria, the most favorable year is 2021, and the unfavorable year is 2019. It was found that with the increase in air and water temperature, the duration and degree of intensity of the temperature optimum zone increased. Consequently, with a further increase in air temperature due to global warming, the duration and intensity of the optimum temperature zone will only increase, which will activate the process of mass development of cyanobacteria, which will negatively affect the ecological state and water quality of the Kuibyshev reservoir.

Методическое и технологическое обеспечение оценки достоверности судебных экспертиз по определению границ водных объектов

The article examines the problems of ecological, environmental, regulatory and technological nature that arise due to the absence of boundaries of zones with special conditions for the use of the territory (ZSCUT) of water bodies. Such zones include water protection zones (WPZ), shoreline protected belts (SPB), flood zones (FZ), underflood zones (UFZ). Shoreline territories are actively involved in eco-nomic use. In order to prevent violations of their legal regime, it is necessary to carry out work to establish the boundaries of ZSCUT. The main problem in this process is the definition of the upper room of the water body, from which the boundaries of all other zones (WPZ, SPB, FZ, UFZ) are constructed. The boundaries of a water body are set depending on its type. To determine the boundary of a water body, information collected by hydrometeorological observation points is used. This information is based on average long-term water levels. The water level value is determined for each water body. According to the relief mark, the boundary of the water body is determined. Therefore, the article discusses the work on entering information about the boundaries of water bodies into the Unified State Register of Real Estate, the features of the legal status of the lands of shoreline territories and the regime of use of special zones, technological features of determining the boundaries of a water body, examples of forensic examinations to check the boundaries of water bodies. Based on the accumulated practical experience in verifying compliance with the requirements of water and land legislation when performing work on the establishment of special zones of water bodies, a number of criteria are recommended. These criteria can be applied in assessing the reliability of forensic examinations to determine the boundaries of water bodies.

Assessment of the intensity of the impact of hazardous hydrometeorological phenomena on the socio-economic system of Belarus

The article is devoted to the study of the problem of the impact of hazardous hydrometeorological phenomena on the population and economy of the Belarus. The indicators determine the intensity of the impact of hydrometeorological factors and take into account the level of socio-economic development of the region. The authors analysed dangerous hydrometeorological phenomena in the period 2008–2020 according to the state network of hydrometeorological observations of Belarus. Statistical method and mapping method were used. The authors assessed the intensity of the impact of the hazardous hydrometeorological phenomena on the basis of a quantitative analysis of the hazardous hydrometeorological phenomena on the socio-economic system of Belarus. Official data on population, area of administrative districts and GRP of regions are the initial data of the National Statistical Committee of the Republic of Belarus. The paper proposes an adapted methodology for a multi-scale study of the impact of hazardous hydrometeorological phenomena on the economy and population in the context of the local level, mesolevel (region) and macrolevel (country) using geoinformation technologies and information electronic database. As a result of the study, it was revealed that the administrative regions of Belarus have unequal vulnerability to dangerous weather manifestations, therefore, the most vulnerable regions of Belarus were identified, for which hydrometeorological services are of particular importance. From the point of view of the intensity of the impact of the hazardous hydrometeorological phenomen on the socio-economic system, the most unfavorable is Minsk Region. The results showed that the higher the population density and the greater the frequency of hazardous hydrometeorological phenomena, the higher the intensity of the possible impact on the population. Accordingly, the higher the GRP, the more significant economic losses can be expected in a particular region of Belarus. Therefore, it is in areas with high GRP that the necessary protective measures should be taken in the first place in order to reduce the consequences of the impact of hazardous hydrometeorological phenomena.

Долгосрочное прогнозирование характеристик весеннего стока рек бассейна Тобола

For the first time, methods have been developed that allow obtaining a long-term forecast of the runoff layer for the second quarter and a forecast of the maximum water level for the spring flood period for seven rivers of the Tobol basin on March 25 every year. Both methods use linear empirical dependences of the predicted value on the maximum snow water equivalent averaged over the catchment area, the logarithm of the average water discharge for November of the previous year, and the average water discharge for the month preceding the forecast release date. To estimate the parameters of these dependencies and verify the forecasts obtained with their help, data of long-term hydrometeorological observations for the period from 1968 to 2021 were used. The analysis of the series of test forecasts showed that both methods give quite satisfactory results for all seven river basins. The methods can be recommended for use in the system for operational hydrological forecasting in order to scientifically substantiate measures on using water resources of the Tobol basin rivers and protecting the population and economic facilities from inundations during the spring flood. Keywords: flood, runoff layer, maximum water level, forecast, snow water equivalent, water discharge, empirical dependence, verification

Farmers’ Perception of Climate Change and Its Impacts on Agriculture

Climate change and climate variability drive rapid glacier melt and snowpack loss, extreme precipitation and temperature events, and alteration of water availability in the Himalayas. There is increasing observational evidence of climate change impacts on water resource availability and agricultural productivity in the central Himalayan region. Here, we assess the farmers’ perception of climate change and its impacts on agriculture in western Nepal. We interviewed 554 households and conducted eight focus group discussions to collect farmers’ perceptions of temperature and rainfall characteristics, water availability, onset and duration of different seasons, and the impacts of such changes on their lives and livelihoods. Our results indicate that the farmers’ perceptions of rising annual and summer temperatures are consistent with observations. Perception, however, contradicts observed trends in winter temperature, as well as annual, monsoon, and winter precipitation. In addition, farmers are increasingly facing incidences of extreme events, including rainfall, floods, landslides, and droughts. These hazards often impact agricultural production, reducing household income and exacerbating the economic impacts on subsistence farmers. Integrated assessment of farmers’ perceptions and hydrometeorological observations is crucial to improving climate change impact assessment and informing the design of mitigation and adaptation strategies.