Monthly Precipitation Amounts Research Articles

Methodology for forecasting precipitation related to El Niño when historical meteorological data are incomplete

The interactions between the ocean and the atmosphere produce various climatic phenomena, such as the El Niño-Southern Oscillation (ENSO), that influence hydrological systems. This study serves as a basis for water resource management and planning in reservoirs and hydroelectric generation, in both the short and long term. A methodology is proposed to study the potential influence of extreme phases of ENSO on the amount of monthly and seasonal precipitation in areas where the weather stations do not have a complete historical data record. A case study is presented of the seasonal precipitation forecast for the largest water reservoir in Mexico. Data from 18 weather stations in the hydrological sub-region Grijalva-La Concordia, in the state of Chiapas, were examined, the highest on the river course of the rainwater catchment dam of the Grijalva Hydroelectric Complex, the most important complex of its kind in Mexico. From the results it is expected that climate change will bring more frequent El Niño phases. The proposed methodology has been validated, making it an effective tool to evaluate the effects of ENSO on precipitation. The methodology is applicable to other regions, particularly in developing countries where historical information is often incomplete.

Seasonal, longitudinal, and latitudinal differences in the amount of precipitation in Russia during the years of maximum and minimum of solar actvity

An analysis of a large array of observation data (over ~50–80 years) for 456 meteorological stations in Russia revealed a distinct difference in the monthly amount of precipitation (DP) during years of maximum and minimum solar activity depending on months and seasons of the year and on latitudes and longitudes. Particularly large DP values are observed in the latitude belt of U = 40–55° N in the longitude range D = 20–40° E in October, DP being 13.6±2.2 mm, as well as in the longitude range D = 110–130° E in June, DP being −8.5±1.0 mm. In the zone of maximum influence of solar activity on the amount of precipitation, a study was conducted on the presence of a correlation between Wolf numbers and the amount of precipitation. As a result, a strong increase in the correlation was discovered in the case of a backward shift in the Wolf numbers, which argued in favor of the influence of solar activity on weather. The author is convinced of the physical significance of the correlation, because it is obtained from data from several geographical points. It is concluded that solar and geomagnetic activity can govern the development of internal instabilities of the atmosphere and thereby influence climate.

Ensemble‐based monthly to seasonal precipitation forecasting for Iran using a regional weather model

AbstractMonthly and seasonal precipitation forecasts can potentially assist disaster risk reduction and water resource management. The aim of this study is to assess the skill of an ensemble framework for monthly and seasonal precipitation forecasts over Iran by focusing on system design and model performance evaluation. The ensemble framework presented in this paper is based on a one‐way double‐nested model that uses Weather Research and Forecasting (WRF) modelling system to downscale the second version of the NCEP Climate Forecast System (CFSv2). The performance is evaluated for October–April period at 1‐, 2‐ and 3‐month lead time. Multiple initial conditions, model parameters and physics are used to construct ensemble members. Using quantile mapping (QM) method, the outputs of the model are bias corrected. This methodology is applied for two periods: (i) climatology from 2000 to 2019 to evaluate the model's ability to precipitation forecast on a monthly and seasonal time scale; (ii) the forecast for 2020 to evaluate the model's performance operationally. The model evaluation is performed using the continuous (e.g., RMSE, r, MBE, NSE) and categorical (e.g., POD, FAR, PC, Heidke skill score) assessment metrics. We conclude that model outputs were improved by the QM bias correction method. According to results, the proposed ensemble framework can accurately predict amount of monthly and seasonal precipitation in Iran with an accuracy of 58 to 45% for lead‐1 to 3. For all three lead times, the averaged NSE, CC, MBE, and RMSE were 0.4, 0.56, −15.5, and 41.6, indicating that the framework has reasonable performance. Our results suggest that precipitation forecast accuracy varies with lead time, so the accuracy for lead‐1 is higher than lead‐2 and lead‐3. Additionally, the model's accuracy differs in various regions of the country and decreases in the spring. Using the approach for an operational case, it was found that the spatial features of precipitation predicted by the framework were close to those observed.

Climate and disease in historical urban space: evidence from 19th century Poznań, Poland

Abstract. This study examines the relationship between temperature levels and precipitation amounts as explanatory variables for the probability of death due to waterborne and airborne diseases in historical urban space. To date, the literature has not focused on the climatological epidemiology of 19th century Polish urban areas. We used individual mortality data from Poznań parish death registers between 1850 and 1900. Each deceased individual was assigned average monthly temperature values and precipitation amounts in the month of death, LAG1 (1-month-lagged) temperature and LAG1 rainfall, and place of residence. We studied the relationship between weather conditions and mortality using formalized statistical models reflecting the discrete nature of the response data (via multinomial logistic regression). Lagged monthly average temperature levels and lagged monthly average precipitation amounts were better predictors of airborne and waterborne disease mortality than the concurrent (non-lagged) monthly averages. The lagged effects of temperature and precipitation on waterborne and airborne diseases were significant (except for the smooth lagged average monthly temperature effect for airborne diseases). There was also significant spatial heterogeneity (differences among city quarters) in the prevalence of deaths due to waterborne and airborne diseases.

Analysis of Monthly Precipitation at the Basin Scale in Türkiye

Basin-based water management strategy is one of the necessary instruments for the protection and sustainable use of water resources against climate change. In this paper, the monthly precipitation distributions of the 25 major basins in Türkiye were produced, and amounts and volumes were computed and analyzed. Only annual modeling and assessments of precipitation may hide months with precipitation shortages. Empirical Bayesian Kriging (EBK), Ordinary Kriging (OK), and Inverse Distance Weighting (IDW) were implemented in interpolation. EBK outperformed in all months and calculations were based on the EBK. The month with the highest precipitation potential in Türkiye is December (77.9 mm, 60.77 billion m3), and the month with the lowest precipitation potential is August (13.8 mm, 10.76 billion m3). In the basins, the monthly precipitation amounts range between 2.7 mm and 185.2 mm, and the volumes range between 0.02 billion m3 and 13.24 billion m3. The basins with the highest precipitation depth were determined as the East Black Sea, Antalya, Asi, and Ceyhan, and the lowest as the Small Menderes, Konya, and Tigris-Euphrates in different months. The monthly precipitation patterns and potentials of the basins vary widely. In May, June, July, August, and September, when water, particularly agricultural irrigation, is required the most, the 20 basins, except for the 5 located in Northern Türkiye precipitation shortage was determined.

Analysis of the dynamics and precipitation regime in the cross-border region Poland-Belarus- Ukraine (2010-2018)


 
 
 The work analyzes the dynamics and regime of atmospheric precipitation in the cross-border region of Poland-Belarus-Ukraine during the period 2010-2018. This time period was chosen, in particular, due to the need to find the prerequisites for the strong shallowing of lake complexes and the depletion of groundwater in the Polish region in 2019, which caused significant social and scientific resonance. The source data for the statistical part of the work were archival information from 17 weather stations in the specified region for this period. The main results of the study: 1) the dynamics of the average monthly precipitation amounts for each meteorological station were calculated and analyzed (Lutsk, Svityaz, Manevychi, Kovel, Liubeshiv, Volodymyr, Rivne, Dubno, Sarny, Brody, Rava-Ruska, Kamianka-Buzka, Pinsk, Pruzhany, Terespol, Wlodawa, Zamosc), the average amounts of precipitation that fell during the warm season of the year (IV-X months) and the cold season of the year (XI-III months), average annual precipitation amounts and precipitation amounts for the entire period, which was investigated (2010-2018). All calculated indicators were compared with the data of the climatic norm of 1961-1990). The annual number of days with precipitation, the warm and cold periods of the year, and the average values of this indicator were also determined. Based on the results of the statistical analysis, charts, cartograms, and several diagrams were developed that visually represent the peculiarities of the dynamics of atmospheric precipitation in the studied region during the analyzed period (2010-2018). 2) on the basis of the calculated indicators, maps of the geographical distribution of precipitation amounts on the territory of the cross-border region Poland-Belarus-Ukraine during the studied period (annual amounts, cold and warm season amounts) were constructed. When comparing them with maps of the period of the 20th century. Changes in the geography of distribution and trends of modern growth of precipitation amounts in the study region were revealed. After the analysis, a number of conclusions and generalizations were made: 1. During the period 2010-2018 in the territory of the cross-border region Poland-Belarus- Ukraine, the average annual amounts of precipitation increased by 20-45 mm compared to the climatic standard, while the average annual number of days with precipitation decreased by 25-30%. 2. Annual amounts of precipitation exceeded 600 mm at almost all (16 out of 17) meteorological stations whose data were analyzed. 3. The distribution of days with atmospheric precipitation during the seasons of the year has changed. The ratio between the amounts of precipitation that fell in the warm and cold periods of the year changed from 75/25 to 60/40 on average. In general, in the studied region, there are trends towards a slight increase in annual precipitation amounts, a redistribution of precipitation amounts in liquid and solid state in favor of rains, and a reduction in the total number of days with precipitation during the year and a more even distribution of them during the warm and cold seasons, compared to the climatic norm.
 
 

Investigation of the effect of climate change on reference evapotranspiration in Tekirdag, Turkiye

It is important to determine the impact of global climate change on water resources. In the effective use of water resources, the amount of water required for agricultural irrigation should be planned under these conditions. In this study, the trend analysis of the climate data required for the calculation of reference evapotranspiration (ET0) between 2011 and 2020 for the meteorology station of Tekirdag, Turkey was carried out. Analysis of change in the study was carried out according to the methods of Linear Regression Test, Mann-Kendall Test and Sen T Test. As a result of the change analysis, it was determined that the reference evapotranspiration (ET0) values had a decreasing trend in June and July and this decrease was statistically significant. As a result of the analysis of the changes in the climate parameters used in the calculation of reference evapotranspiration (ET0), it was determined that the values of maximum temperature, average relative humidity and average sunshine duration were in a decreasing trend, while minimum temperature and wind speed values were in an increasing trend. In the study, the change in monthly precipitation amounts during the measurement periods was also examined. As a result of the analysis of the changes, it was determined that the monthly precipitation amounts have a decreasing trend and the changes especially in April, September, October and December are statistically significant. It is thought that the results obtained will contribute to the future agricultural production planning in the regional conditions.

Potential future distribution of Scirpophaga incertulas (Walker) in Indonesia

Scircpophaga incertulas is a caterpillar that lives in rice stalks and can damage rice crops from seedling to maturity. One factor that influences this pest’s presence is the climatic factor. This study aimed to map the future potential distribution of Scircpophaga incertulas (2100). The method utilized in this study was the Species Distribution Model (SDM) from the web-based modeling platform Ecocommons by using the Artificial Neural Network (ANN). For current and climatic projections (the year 2100), the open-source climatic data from CliMond were used. The ANN result shows the climatic factors contributing to this species distribution are annual precipitation amount by more than 80%, followed by the mean monthly precipitation amount (the warmest quarter by precisely 80% and the coldest quarter by 62%). The SDM analysis indicates that around 23.07% of Indonesia’s archipelago is highly suitable for Scircpophaga incertulas in 2100, while in the current situation, 33.03% is suitable. This study deduces that the highest suitability for this pest distribution will cover 80% of the Java Island area in the future. In contrast, this species’ potential distribution in Papua will decline from 46.86% to 21.29% in 2100.

Analyzing changes in land use practices and livelihoods in the Bhungroo irrigation technology Volta basin piloted sites, West Mamprusi District, Ghana

This study focused on assessing agricultural land use practices and livelihood changes as affected by long-term erratic rainfall patterns characterized by flood and drought cycles in the Bhungroo Irrigation Technology (BIT) piloted sites, West Mamprusi upper and lower catchment area in Ghana. The study defined environmental flow restoration (EFR) factors based on irrigation water demand, natural outflows (e.g. drainage, seepage and percolation), evaporative outflows, rainfall and stored water. Agro-ecological resilience (AER) factors included flooding intensity, crop production under dry season, flood recession, and irrigation, and livestock as well as mixed farming was assessed. The framework of Evaluating Sustainable Land Management (FESLM) was utilized to assess changes in land use and trends analyzed by the Auto Regressive Integrated Moving Average (ARIMA) technique. The main observed land use practices were subsistence cultivation with limited irrigation 72.8%, subsistence cultivation without irrigation 64.5% and livestock keeping with some cultivation 87.4%. Corresponding land use mean weights impact on the EFR and AER were 9, 9, 8, and 9, 8, 7 respectively. The study noted that precipitation was of higher significance than temperature in terms of hydro-climate determinants in both upper and lower catchment areas. Mean monthly precipitation amount and intensity were highest between June–July in the upper catchment while in the lower catchment it was between July–August. These months corresponded with high risk of flooding and waterlogging in both catchments. The opposite was observed in March with access to irrigation water being the most EFR factor influencing the resilience of BIT especially at the upper catchment area. In terms of academic contribution, this paper posits in the hydro-climatic context that excess pressure exerted from a combination of micronized factors such as waterlogging of farmlands, flood recession rate, irrigation capabilities, climate preparedness, adoption and transferability of innovations and scalability of climate innovations are likely be the critical elements which accelerate the climate vulnerability of arid and semi-arid catchment areas. Based on these observations, the study carefully recommends improved BIT infrastructure, including the integration of grundfos pumping systems, solar pay-as-you-go energy, MTN mobile payment systems, participatory decision support systems (PDSS), with improved awareness on determinants of EFR including crop-livestock integration in ecological organic agriculture as resilience building options.

Seasonal variations in total deposition velocity and washout ratio of fine aerosols revealed from beryllium-7 (7Be) measurements in Sevastopol, the Black Sea region

Washout ratios and deposition velocities are crucial in fine aerosols as they affect their atmospheric concentration, which in turn impacts human health. The only method to estimate the total (dry and wet) aerosol deposition velocity or washout ratio is by using a tracer such as beryllium-7 (7Be). This study collected field data on the temporal variability of monthly total deposition flux of 7Be and monthly mean 7Be activity in Sevastopol station, the Black Sea region from March 2011 to December 2013. From these data, the washout ratio and deposition velocity of fine aerosol particles were derived. The monthly mean values of the washout ratio and deposition velocity ranged from 388 to 3533 (mean 1112 ± 793) and from 0.1 to 1.5 cm s−1 (mean 0.6 ± 0.4 cm s−1), respectively. The dry deposition velocity in the four precipitation-free months varied between 0.10 and 0.15 cm s−1 with an average of 0.13 ± 0.02 cm s−1. The precipitation amount and frequency strongly influenced the seasonal variability of the deposition velocity, whereas the seasonal variability of the washout ratio was controlled only by the precipitation amount. The reduced washout ratio and the increased deposition velocity were associated with the increased precipitation. Thus, the results obtained allowed for parameterizations to estimate the monthly mean values of the washout ratio and deposition velocity from the data of the monthly precipitation amount.

The correlation in the dynamics of the growth of European spruce and the dynamics of potato and winter rye yields

The subject of the study was the meteorological conditionality of fluctuations in the radial growth of European spruce in a single local old-age stand, as well as the conjugacy in fluctuations in the growth indices of European spruce and crop yield indices (winter rye, potatoes) over an 80-year time interval. The study uses time series of yields of winter rye (Secale cereale L.) and potatoes (Solanum tuberosum L.) obtained in the long-term experience of the Timiryazev Agricultural Academy (originally laid down by D.N. Pryanishnikov) for the period 1912-1991. The long chronology of the European spruce (Picea abies (L.) H.Karst.) was obtained on the basis of cuts selected after the wind in the Alekseevskaya grove of the Losiny Ostrov National Park and covers the period 1812-2017. To identify the conjugacy between fluctuations in the indices of radial growth of spruce and meteorological parameters, as well as to identify the conjugacy in fluctuations in the indices of growth of spruce and Correlation analysis was used for the yield indices of winter rye and potatoes. Correlation analysis showed that the formation of spruce growth is positively influenced by elevated temperatures in December and January, negatively affected by elevated temperatures in June in the calendar year of the formation of the annual ring and elevated temperatures in August in the year preceding it. Reliable correlation coefficients of spruce growth indices with monthly precipitation amounts were not found in the ecotope under consideration. Significant correlations were revealed between the dynamics of spruce growth indices and the dynamics of crop yields: the relationship with potato yields in the experiment without lime, without crop rotation and with the application of NPK fertilizers and manure (correlation coefficient 0.22) and the relationship with rye yields in the experiment without lime, without crop rotation and without fertilizers (correlation coefficient 0.23).

Improved teleconnective predictability of monthly precipitation amounts using canonical correlation analysis

This study was aimed at evaluating the application of the canonical correlation analysis (CCA) to predict monthly precipitation amounts (predictands) by benefitting from 17 large-scale climate indices (predictors) in Iran. Monthly precipitation data, covering the period of 1987–2017, were collected from 100 weather stations across the country. Monthly precipitations were predicted using the multiple linear regression (MLR) models, based on the 1- to 6-month lead times of the original and canonical predictors. The cross-validation was conducted to compare the prediction skills of the two sets of MLR models constructed on the basis of the original predictors (MLOrigPr) and the canonical predictors (MLCCAPr). The analyses revealed the dominant teleconnections and that there are the interannual variations in responses of precipitation to them suggesting that a signal only is not sufficient to achieve a robust understanding of the associations. At the 1-month lead time, the MLR models based on the canonical predictors outperformed those based on the original predictors. However, the skill of both models was reduced by increasing the lead times up to 6 months. Averaging on all stations, around 61.4% and 26.3% of the observed values, falls into the cross-validated 95% prediction intervals of the MLCCAPr and MLOrigPr models, respectively. Furthermore, the MLCCAPr models were found to be more spatially universal than the MLOrigPr ones and decrease multicollinearity symptoms strengthening the predictions. These findings corroborated the advantage of using the CCA in improving the teleconnective predictability of precipitation in Iran.

Modeling the Water Balance of Agricultural Land in the Determination of the Growing Season in Buru Regency

This study aims to determine the value of surplus and water deviation of agricultural land in Namlea District, Buru Regency. The study was conducted in Namlea Subdistrict, Buru Regency, Maluku Province. Materials used, questionnaires, climate data, air temperature, precipitation, humidity, solar rays 10-20 years. Tools used, computer equipment, writing stationery and location maps. To obtain the surplus value and water deficit of the land used data on the average amount of monthly precipitation and the average monthly temperature using the calculation of the Thornthwaite method. The calculation of the groundwater balance is carried out using a bookkeeping system. The data used are monthly potential evapotranspiration values, climate station data, monthly average rainfall, and rainfall at a 50 percent chance level. The observation parameters calculated in this study are rainfall, evapotranspiration, and determination of land water balance. The results of this study showed that the difference in rainfall and evapotranspiration in Namlea District was highest in June at 85.40 mm, and the lowest in October at -99.83 mm. This value indicates that the evapotranspiration value is greater than the average monthly rainfall value during the period 2010 – 2019. Namlea Subdistrict experienced potential water loss for evaporation (APWL) in May of 35.30 mm, in August to November of August of 65.26 mm, in September of 156.24 mm, in October of 256.07 mm and in November of 303.45 mm. The land water balance in Namlea Subdistrict, namely rainwater deviation, occurs in May, then August to November, while the water surplus occurs in December to July, and continues in June and July. Namlea district annual runoff is 854.01 mm. Regarding agricultural irrigation development policies, this study recommends that it is necessary to pay attention to weaknesses in each food crop sub-sector.

Prediction of changes in the vegetation cover of Ukraine due to climate warming

Purpose. To study ecological regularities of the formation of vegetation cover in Ukraine depending on the climatic conditions and analyze its possible changes due to global warming. Methodology. The research methodology involves the following: differentiation of the climatic conditions and evaluation of the significance of climatic indices at the level of territorial units of a geobotanical zoning based on variance analysis; multiple ordering of the geographic locations in terms of climatic indices basing on the analysis of main components (Principle Component Analysis); development of a typological scheme of the vegetation cover relying upon a discriminant analysis; statistic processing of the climatic parameters. Findings. Modelling of spatial differentiation of climatic indices depending on the location latitude and longitude as well as altitude above the sea level helped analyze the connection of vegetation cover and climate. It has been determined that peculiarities of the vegetation cover formation according to a scheme of geobotanical zoning is characterized in the most accurate way by the difference of such climatic indices as: air temperature in January, July, and August; monthly precipitation amounts during June-September; duration of a frost-free period; and hydrothermal coefficient of T.G. Selianinov. The main regularity of the formation of Ukrainian vegetation cover has been defined. The regularity means the following structure of interrelation between the climatic indices: along with the growing average monthly temperatures of June-September and decreasing precipitation amounts from April to September, the indices of climatic water availability decrease along with the increasing heat availability indices (duration of an active vegetation period and total of temperatures per that period, average annual temperature). This regularity represents a gradient of climatic indices from the Ukrainian Carpathians towards the southern Crimean coast. It has been determined that during some years of the early 21st century, the conditions peculiar for a steppe area were formed for the forest and forest steppe areas. Originality. The vegetation cover of Ukraine is characterized by the ecological range, which is evaluated basing on ordering of the geographical locations in terms of coverage of complex climatic environmental gradients. A typological scheme of the Ukrainian vegetation cover can be represented in a two-dimensional space in the form of square parabola, whose left branch shows a gradient of climatic factors and changes in vegetation cover from the west to the north-east and right branch indicates it from the north-east to the south. Graphic visualization of climatic information on the basis of ecograms and typological schemes of vegetation cover can be used to predict the vegetation cover dynamics due to certain climatic changes. Practical value. While understanding the climatic conditions of geographic locations during certain periods of time, one can identify their location in the ecological and coenotic range of Ukrainian vegetation and predict their stability and possible changes in the vegetation cover due to global warming.

Assessing Gridded Precipitation and Air Temperature Products in the Ayakkum Lake, Central Asia

We evaluated the performance of gridded precipitation and air temperature datasets near the Ayakkum Lake at the southern margin of Xinjiang, arid central Asia. Statistical measures were applied to assess these climate products on a monthly basis from 2013 to 2018. For monthly precipitation amount, the European Centre for Medium-Range Weather Forecasts Reanalysis 5 shows a good performance among the five products based on most statistical measures, and the China Meteorological Forcing Dataset can also be used as an alternative, especially for estimating the long-term annual mean. For monthly air temperature, WorldClim historical weather data are recommended because of the low mean absolute error, root mean square error and distance between indices of simulation and observation. Better spatial and temporal coverages of in-situ observations are still needed to produce an optimal correction scheme for the mountainous regions of arid central Asia.

Assessment of the influence of weather factors on the quantitative indicators of sweet cherry fruits by Ridge regression

Sweet cherries are a favourite stone crop among consumers of fruit products. At present, the demand for sweet cherries is growing, which encourages the expansion of the varietal range of crops with different ripening periods. The purpose of this study was to develop a mathematical model for predicting the formation of fruit and sweet cherry pyrene mass depending on weather factors and varietal characteristics. The study was conducted during 2008–2019 in the conditions of the Southern Steppe zone of Ukraine on 33 varieties of sweet cherries of early, medium, and late ripening periods. The average mass of the sweet cherry fruit over the years of research was 8.41 g, and the average mass of the pyrene was 0.56 g. Late-ripening sweet cherry varieties had the best fruit mass (7.27–12.18 g). According to the maximum average mass of the fruit, the varieties Kazka, Dilema, and Kosmichna were distinguished. Sweet Erlise, Pervistok, Melitopol black and Krupnoplidna varieties had the lowest pyrene mass in sweet cherry fruits. In the group of early ripening, the best ratio of pyrene to fruit pulp was found in the Kazka variety, in medium-ripening varieties – Cordia, Perviystok, and Orion, in late-ripening varieties – Udivitelna, Krupnoplidna, and Prazdnichna.The smallest variability in sweet cherry fruit mass in the group of early-ripening varieties was detected in Sweet Erlise, in mid-ripening – Temp, and in late-ripening – Regina, while in pyrene mass – Rubinova Rannia, Vynka and Regina, respectively. Weather conditions had a dominant influence on the formation of fruit mass for all sweet cherry varieties under study, and varietal characteristics had a dominant effect on pyrene mass. The maximum influence on the formation of sweet cherry fruit mass of early varieties was provided by the indicator – the number of days with precipitation in May exceeding 1 mm, and for medium and late ripening varieties – the average monthly amount of precipitation in June. Decisive importance for the formation of pyrene mass in sweet cherry fruits of early ripening varieties was the average monthly amount of precipitation in May, in the middle ripening period – the average monthly amount of precipitation in June, in the late ripening period – the number of days with precipitation exceeding 1 mm in May.

Analysis of climate changes in the forest fund lands of Boyarka Forest Research Station

The relevance of the study is conditioned upon the predicted changes in the area, as well as the significant narrowing of the zone of optimal growth of Scots pine. These forecasts are based on obtaining data on the ongoing climate changes. A constant decrease in precipitation, along with a gradual increase in temperature levels, will lead to consequences such as uncontrolled changes in ecosystems. Such a substantial change in abiotic factors caused by human activity plays a key role in the formation of forest coenoses. The main purpose of this study was to analyse the change in the average annual temperature, as well as the monthly amount of precipitation observed in the forest communities in the Separated Subdivision of the National University of Life and Environmental Sciences of Ukraine “Boyarka Forest Research Station”. The analysis is performed over decades to obtain data on the level of temperature change in relation to the previous period. This also includes a comparison of monthly precipitation for 2021 relative to 1991-2020, which is set as normal. To obtain indicators of the average annual temperature, the average value method is used, followed by calculating the value of the average annual temperature for each decade. To find the deviation in total precipitation, the method of estimating the moisture conditions according to total precipitation is used. Therewith, the value of a substantial deviation is taken at 20% relative to the precipitation rate. According to the study results, it was established that in 2001-2010 the average annual temperature changed by 0.83°C relative to the previous decade, and in 2011-2020 by 0.74°C relative to the previous period. Such dynamics indicate a gradual increase in the average annual temperature, which is reflected in the forecasts of the world community. During the estimation of moisture conditions, separate months of 2021 with a critical level of precipitation in relation to the normal period were selected. In March, the amount of precipitation was 43% of normal, in June – 32%, in September – 40%, and in October – only 4.3% of normal. The value in November was observed at 63% of the norm. Such a decrease in the amount of precipitation in relation to a gradual increase in the average annual temperature poses a threat of a decrease in the hydrological level of moisture. This leads to a decrease in the radial increment of tree stands, and a gradual shift in the growing area of Scots pine. The obtained analysis results will further be used to conduct dendrochronological studies of tree rings of Scots pine (Pinus sylvestris L.) in the tree stands of the Separated Subdivision of the National University of Life and Environmental Sciences of Ukraine “Boyarka Forest Research Station”

Dendrochronological analysis of the influence of climate on autochthonous and introduced coniferous tree species in the city park “Prostor”, Kardzhali

The study focuses on the response to climate change of indigenous and introduced coniferous tree species – Austrian black pine (Pinus nigra Arn.) and Colorado spruce (Picea pungens Engelm.) situated in the urban city park “Prostor” in the town of Kardzhali. A multifactor regression analysis was used in the frame of the dendrochronological studies to establish the functional dependence “climate – radial growth”. The model was tested in a climate window with a segment of 16 years – from 2005 to 2020. The data for air temperature and monthly precipitation amounts for Hydro-meteorological station (HMS) Kardzhali were used as predictors for the radial growth. = Both species’s indifference to the temperatures and rainfalls during the months August and September, crucial for the ring formation, leads to the absence of significant growth depressions in tree-rings chronologies and justifies the good condition of the studied trees.

Precipitation evaluation of the North Dakota Cloud Modification Project (NDCMP) using rain gauge observations

The North Dakota Cloud Modification Project (NDCMP) is a state-managed, cost-sharing weather modification program with a primary goal of reducing crop hail damage and a secondary goal of increasing precipitation. North Dakota has conducted NDCMP in western North Dakota since 1976. This analysis evaluates the 1977–2018 cloud seeding impact on rain gauge measured precipitation using an exploratory historical target/control statistical analysis. Three counties where seeding is conducted each year are target areas: McKenzie, Bowman, and Ward. Neighboring counties where little or no seeding occurred are control areas. Averages of available daily rain gauge measurements provide monthly and seasonal (June–August) area precipitation amounts for the target and control areas. Double ratio statistics are determined using the pre-NDCMP period of 1950–1975 and the NDCMP period of 1977–2018. The statistics use the McKenzie and Bowman target areas paired with four different control areas, along with the Ward target area paired with one control area. Six of eight McKenzie and Bowman target/control pairs have double ratios (1.01–1.12) possibly indicating higher target area precipitation during NDCMP. Additionally, two of eight ratios have a 95% statistical chance of being greater than 1.0. The Ward target/control comparison indicates no enhancement. The average of all nine target/control ratios is 1.03, consistent with a modest overall precipitation enhancement by NDCMP hail suppression operations.

Geochemical Study on the Annual Variation of Oxygen Isotope and Chemical Composition of Groundwater in the Sho River Alluvium Fan, Toyama, Japan, as an Investigation of Selected Qualitative Aspects of Efficient Utilization of Groundwater Heat

Seasonal variations of water temperature, electric conductivity, and oxygen isotope and chemical composition of shallow groundwaters and river waters were determined in the Sho River alluvial fan, western Toyama Prefecture, Japan, to examine groundwater heat utilization for indoor climate control. Samples were collected at 31 sites every 2 months for 1 year and at 11 representative sites monthly. In addition, the results of monthly precipitation amount and oxygen isotope composition of precipitation collected within the region during the same period were also taken into account. The sources of the shallow groundwaters are a mixture of river water and precipitation. The contribution of precipitation to groundwater is generally small along the Sho River but reaches as much as 80% along the Oyabe River and in the south and west of the alluvial fan. Though the origin of the groundwater differs regionally, water temperature is fixed at around 15 °C throughout the year in the northern part of the alluvial fan, and open-type ground source heat pump systems can be used for cooling and heating there, if adequate quantitative aquifer properties (exploitable groundwater amounts) are present.