Average Monthly Air Research Articles

Современные агроклиматические условия горных ландшафтов Северного Кавказа

Introduction. For the first time, the problem of global warming was officially announced in 1976 by the World Meteorological Organization. The most complete picture of ongoing climate change, causes, consequences and response strategies can be obtained from the reports of the IPCC (intergovernmental group of experts). There are many works devoted to regional climate changes, including those in the North Caucasus. However, these works do not reflect the modern agro-climatic conditions of the mountainous landscapes of the North Caucasus which occupy 27% of the territory and are actively involved in agriculture. Aim - analysis of modern agro-climatic conditions of the mountain landscapes of the North Caucasus in a changing climate. Materials and research methods. To assess agro-climatic conditions, traditional agro-climatic indicators were used, such as annual and average monthly air temperatures; sums of active temperatures exceeding 5 and 10°С; dates of stable transition of the average daily air temperature through 0, 5 and 10°C in spring and autumn; the duration of the period with an average daily temperature of 0, 5, 10 ° C, the average temperature of the coldest and warmest months of the calendar year, annual precipitation, hydrothermal coefficient. The processing of the material was carried out by methods of mathematical statistics using Excel spreadsheets. Processed data on temperature and precipitation in the period from 1961 to 2020 for six meteorological stations. Research results. For the period from 1961 to 2020, within the mountain landscapes of the North Caucasus, there is an increase in annual air temperature compared to the previous period by an average of 0,5 °C. Against the background of an increase in annual temperature, such agro climatic indicators as the sum of active temperatures increased, exceeding 5o and 10oC by 6 and 13%, respectively. The stable transition of the average daily air temperature through 0, 5, 10°C has also undergone changes. In spring, on average, this happens 5, 1, 6 days earlier. Whereas in autumn, on the contrary, 3, 1, 5 days later. The duration of the period with an average daily temperature of 0, 5, 10 °C increased by an average of 10, 3, 13 days, respectively. Precipitation increased at all meteorological stations, with the exception of the Klukhorsky cross, by an average of 45 mm. The hydrothermal coefficient, which characterizes precipitation during the growing season, remained within the limits of natural fluctuation, except for the Klukhorsky cross, where it decreased due to a decrease in precipitation during the warm period. Discussion. The analysis of the agro-climatic conditions of the mountain landscapes of the North Caucasus for 1961-2020. revealed trends in the growth of annual temperature and precipitation, however, the moisture supply of the active vegetation period, estimated using the HTC, remained unchanged. Our results correlate with the official data of Rosgydromet, published in the Report on the peculiarities of the climate of the Russian Federation for 2021. Conclusion. The study allows us to state that in the mountainous landscapes of the North Caucasus, climatic changes proceed according to the scenario of an increase in air temperature and precipitation. As a result, agro-climatic indicators have changed: the sum of active temperatures has increased, exceeding 5o and 10oC and the duration of the period with an average daily temperature of 0, 5, 10oC, the dates of a stable transition through 0, 5, 10oC have changed, precipitation has increased, but the HTC has remained within the natural fluctuation . The stability of the HTC indicator indicates the stability of landscape boundaries, despite the observed changes in agro-climatic indicators. Resume. The observed climatic changes within the mountain landscapes of the North Caucasus contribute to an increase in the productivity of agricultural production by improving the conditions for heat and moisture supply to the territory. Suggestions for practical application and direction for future research. The results of the study can be useful for updating the schemes of agricultural zoning of the mountainous territories of the North Caucasus, as well as for developing land use schemes based on contour farming, which reduces the risks of adverse natural phenomena, including those caused by climate change.

FEATURES OF SPRING ICE PHENOMENA ON BALKASH LAKE IN EXTREMELY WARM MONTHS

In this paper we are considering the processes of ice destruction on Balkash Lake during extremely warm months. A significant correlation found between the average monthly air temperature of March and the dates of ice destruction beginning, complete freezing ending and water clear of ice. The Bagrov-Tokarev anomaly criterion for March was calculated and the extreme months were determined. The features of ice destruction during the spring season for the years with extremely warm months were analyzed. The number of days with certain types of ice phenomena are calculated, the various types of ice phenomena were analyzed for extremely warm months. The maps of ice thickness distribution were compiled. The deviation of the dates of ice destruction beginning, complete freezing ending and water clear of ice from the averages dates in extremely warm months was found. The data source were hydrological guides, monthly average air temperature data, and data reanalysis using the CDS Copernicus climate database of the European Center.

СОВРЕМЕННОЕ СОСТОЯНИЕ РЕСУРСОВ ВЛАГИ НА ФОНЕ КЛИМАТИЧЕСКИХ ИЗМЕНЕНИЙ НА СЕВЕРО-ВОСТОЧНОМ СКЛОНЕ БОЛЬШОГО КАВКАЗА (В ПРЕДЕЛАХ АЗЕРБАЙДЖАНСКОЙ РЕСПУБЛИКИ)

The paper presents the results of our investigation of the moisture resources on the northeastern slope of the Greater Caucasus. For this purpose, standard meteorological data archives of the Siyazan, Khachmaz, Guba, Khaltan and Gyryz meteorological stations located at different heights of this slope were used for the period of 1966-2005. Regional climate changes were assessed by comparing the average monthly air temperature and the amount of precipitation using the diff method for 1961-1990 and 1991-2005. Long-term trends in the change in the total amount of atmospheric precipitation, the Selyaninov HTC andD.I. Shashko’s moisture index for the warm period of the year and the ratio of the precipitation amount for the warm period to the annual precipitation amount were evaluated. It was found out that the multi-year tendency of the precipitation amounts during the warm period has not actually changed.

Contemporary Climate Change and Its Hydrological Consequence in the Volga Federal District, European Russia

An analysis of spatiotemporal variability of air temperature and precipitation in the Volga Federal District (European Russia) between 1966 and 2021 was carried out. Based on data from 20 meteorological stations, relatively evenly located on the territory under consideration, the spatial distribution of average monthly and average annual air temperatures and monthly and annual precipitation was assessed; some indicators of the temporal variability of these variables in the period under consideration were calculated and analyzed. It was revealed that throughout the Volga Federal District, there was a tendency of climate warming in all months, and a slight increase in annual precipitation, except for the southeast of the district, where the precipitation trend was negative. It is noted that in the period 1955–1998, the number of negative air temperature anomalies was approximately equal to the number of positive ones; however, in the later period 1999–2021, the number of positive anomalies significantly exceeded the number of negative ones. Based on reanalysis data, climatic maps of vaporization and runoff in the Volga Federal District during 1966–2021 were created. The dependence of air temperature fluctuations on the nature of atmospheric circulation was revealed using the NAO, AO, and SCAND indices. On the example of the central part of the district (Republic of Tatarstan), some increase in summer aridity of the climate was revealed by using Budyko’s dryness index, Selyaninov’s hydrothermal coefficient, and Sapozhnikov’s humidification coefficient. The indicators of runoff and evaporation were also calculated using the methods of Schreiber and Ivanov. Against the background of the positive trend in vaporization rates, favorable conditions for a decrease in runoff were noted.

Estimation of dissolved organic carbon from inland waters at a large scale using satellite data and machine learning methods

Dissolved Organic Carbon (DOC) in inland waters plays an essential role in the global carbon cycle and has significant public health effects. Machine learning (ML) together with remote sensing has emerged as a powerful and promising combination to quantify water quality parameters from space. However, inland water sample data for DOC is limited. Hence, little is known about the potential to quantify DOC content in inland waters, especially over large-scale areas. This study presents the first attempt to estimate DOC in inland waters over a large-scale area using satellite data and ML methods with the newly published open-source dataset AquaSat. Four ML approaches, namely Random Forest Regression (RFR), Support Vector Regression (SVR), Gaussian Process Regression (GPR), and a Multilayer Backpropagation Neural Network (MBPNN) were trained using more than 16 thousand samples across the continental United States matched with satellite data from Landsat 5, 7 and 8 missions. Satellite data from the Landsat missions were further extended with environmental data from the ERA5-Land product and used as input to train the ML algorithms. Our results show that including environmental data as inputs considerably improved the prediction of DOC for all ML algorithms, with GPR showing the most promising performance results with moderate estimation errors (RMSE: 4.08 mg/L). Permutation feature importance analysis showed that the wavelength range in the visible Green band (from Landsat) and the monthly average air temperature (from ERA5-Land) were the most important variables for the ML approaches. The results demonstrate the predictive strength of GPR and its useful feature to derive per pixel standard deviations for detailed analysis. Our results further highlight the important role of considering environmental processes to explain DOC variations over large scales. The application and performance of the GPR in mapping spatiotemporal variations of DOC in an entire water body were discussed by taking Lake Okeechobee (the 8th largest freshwater lake in the U.S.) as an illustrative example. While performance evaluation showed that DOC concentrations can be retrieved with adequate accuracy, algorithm development was challenged by the heterogenous nature of large-scale open source in situ data, issues related to atmospheric correction, and the low spatial and temporal resolution of the environmental predictors. This research demonstrates how open source, large-scale datasets like AquaSat in combination with ML and satellite remote sensing can make research toward large-scale estimation of inland water DOC more realistic while highlighting its remaining limitations and challenges.

Forecast of changes in climate factors of the city of Kyiv and their impact on the life cycle of buildings

The problem of global climate change is one of the most important problems of society. Such relevance is due to the fact that the change in climatic parameters has a significant impact on the economic sphere, the ecological situation, social and political life, and the construction industry. The change in the parameters of climate systems has long been beyond doubt. In recent years, due to the perceived threat of global climate warming, interest in long-term interannual climate fluctuations has increased significantly. Therefore, one of the unquestionably relevant tasks is the monitoring of trends in changes in climatic indicators at the local (regional) level. It is these observations on a regional scale that allow us to detect cyclical fluctuations in meteorological values and further judge the change in the Earth's climate in general. When building urban quarters in difficult natural and climatic conditions, along with urban planning and architectural and planning methods of organizing residential structures, one of the key points is the correct selection of fencing materials and structures. Special attention should be paid to their physical properties, thermal conductivity, specific resistance, optical reflectivity, etc. It is also necessary to take into account the location of the construction site, because due to macro- and micro-scale climate-forming factors (radiation conditions, wind regime, form of meso- and microrelief, vegetation, soil, close proximity to the sea, surrounding buildings, etc.) and their due to joint influence in different areas of the city, the difference in temperature and humidity can be significant. The article examines the peculiarities of the manifestation of climatic changes for the city of Kyiv in the context of engineering and construction adaptation and the selection of building materials to create more comfortable living conditions for the residents of the metropolis. It was established that during the last decades in the city the average annual air temperature increased by 0.7–1.2°С, compared to the climatic norm. The most significant increase in the average monthly air temperature in the modern period in the city is observed in the winter and summer months. According to calculations, the average annual temperature will rise gradually and increase by an average of 2.0–2.5°С. On the basis of this, the necessity of conducting further research, creating scientific and practical recommendations, especially in the conditions of modern megacities, which are a factor in climate formation, has been proven. The article analyzes the impact of changes in climatic factors on the life cycle of buildings.

The retrospective monitoring of soils under conditions of climate change in the Trans-Ural region (Russia)

Global climate change is a fact that affects all components of the environment. The main aim of this research was to conduct the retrospective monitoring of soils in the Trans-Ural Steppe Zone (Russia) and the analysis in changing of key climatic parameters for the periods 1937–1982 and 1982–2019. We investigated average temperatures and precipitation (monthly and annual) using archived data from a nearby weather station, as well as data from NASA and weather forecast websites. We identified a decrease of soil fertility and an increase in alkalinisation processes over the past 37 years for the studied area. Comparison of these periods showed an increasing the average monthly and annual air temperatures (on 1.4°C) and a decrease in the amount of precipitation in the summer (on 4.4 mm) period. We found that a more arid climate accelerates the rate of soil salinization due to the active evaporation of groundwater. Nevertheless, in some areas there were found the soil desalinization due to the change in the hydrologic regime and lowering of the groundwater level. In general, the climate changing in the studied region is consistent with global warming trend. Increased average annual temperature and reduced precipitation in summer period contribute to aridization of the region. Such conditions will more restrict soil fertility due to development of salinization and desertification processes.

The role of mineral fertilizers in increasing the productivity of oats (Avena sativa L.) under changing climatic conditions of the steppe Volga region

The results of the effectiveness of the use of mineral fertilizers on oat crops in a six-field crop rotation (8 rotations, 24 years of cultivation) under conditions of a long stationary experiment on the chernozem of the southern steppe Volga region are presented. The nature and direction of natural changes in agro-climatic parameters during the period of oat cultivation and the level of their influence on its productivity when applying various doses of mineral fertilizers are determined. During the studied period, there was a tendency to increase the aridity of the climate, which was expressed in a decrease in the values of the hydrothermal coefficient and an increase in the sum of active temperatures. In the experiment, in the period from 1-4 to 5-8 rotation of crop rotation, there was a tendency to increase the average monthly air temperature in July. It was found that these climatic changes contributed to a decrease in the productivity of oats in the experiment. At the same time, the share of increases in relation to the control in the obtained yield values on fertilized variants increased. The most effective were medium and high doses of nitrogen-phosphorus fertilizers.

Temporal variability of daily precipitation concentration in Japan for a century: Effects of air temperature rises on extreme rainfall events

Climate change induced by air temperature rises may have a significant impact on change in rainfall patterns. Indeed, flood disasters due to downpours have increased over the last few decades in Japan. This study considers the Lorenz Curve, a concept used in economic theory, to describe spatial-temporal variability in the daily time series of precipitation concentration. The results reveal that annual average air temperature has risen at 10 rural sites and 5 urban sites over the period from 1901 to 2020 (120 years). The obtained trends are positive, and statistically meaningful at the 1% level. Whereas, annual precipitation has not changed significantly in the period (1901–2020) since obtained trends at all 15 sites are non-statistically meaningful (p > 0.01). In the meantime, annual maximum daily precipitation has increased for 1 of 15 sites, i.e. Ishigaki, while annual maximum hourly precipitation has increased for 4 of 15 sites, i.e. Choshi, Sapporo, Tokyo and Fukuoka. Calculated Gini coefficient, i.e. the precipitation concentration index (CI) has increased at all 15 sites in the period (1901–2020). The trends are positive, and statistically significant (p < 0.01). This indicates that rainfall has become more concentrated into a fewer rainy days throughout a year as the air temperature has risen for the 120 year period. The correlation between the precipitation CI and warming trends of individual monthly average air temperatures are weak, i.e. almost no correlation, for April, May, June, and November. Whereas, the obtained Spearman's rank correlation coefficient ρs = 0.78 and 0.72 indicate a strong correlation between the trend in air temperature rises and the trend in precipitation CI for July and August. This suggests that air temperature rises during summer (July and August) play an important role in the change in precipitation characteristics throughout Japan.

AIR POLLUTION AND HEALTH: PARTICULATE MATTER PM2.5 MEASUREMENTS IN CANTONMENTS, GHANA

Particulate matter (PM) air pollution research has improved our understanding of major pollution sources and the quantification of their impact. Although several PM studies have been conducted in Accra, Ghana, in recent decades, few have offered an integrated knowledge of PM sources in the various sub-cities. The purpose of this study was to consolidate data and investigate additional aspects of PM investigations of Cantonments, a residential neighborhood in Ghanas capital. There is evidence of poor air quality in Accra, particularly during the dry season (Harmattan season). From December through February, a severely dry, dusty easterly or north-easterly wind sweeps over the West African coast, causing Harmattan. The PM2.5 concentrations for Cantonments for two years and the average monthly air quality indices were analysed and discussed. The results reveal the need to regularly check the daily air quality indices and curb their impacts since it has a notable health effect on the general public. KEYWORDS: PM2.5; Air pollution; Public health; Accra; Ghana

Climate Change Impact on the Duration of Great Vegetation Period and Vegetation Period of Beetroot and Watermelon in Slovakia

Climate change brings to the whole world numerous challenges such as an increase in the global temperature, weather fluctuations, periods of drought and heat alternating the local floods. While the majority of the effects are negative for agricultural production, some can be beneficial. Our work presents the evaluation of the changes in the duration of the great vegetation period (delineated with the beginning and end of days with an average temperature T ≥ 5.0 °C) and the vegetation periods of watermelon (Citrullus lanatus Thumb.) and beetroot (Beta vulgaris L.). Data sets on the average monthly air temperatures for the period 1961–2020 from one hundred agroclimatic stations in Slovakia were selected for the estimation of the future average air temperatures using statistical methods (linear trendline). Based on the temperature requirements of the selected crops, the potential maximum duration of the vegetation period was estimated for several decades from 2041 up to 2100. The results clearly showed prolongation of the vegetation periods and changes of their zonation in Slovakia. In 2011–2020, the duration of the beetroot vegetation period in the southernmost part of Slovakia (Danubian Lowland) was 15–20 days longer than in decade 1971–1980. It is expected, that this value will rise by another 10–15 days in decade 2091–2100. Since 1971–1980, watermelon vegetation period duration increased by 5–10 days when compared to decade 2011–2020. It is expected that by 2091–2100, its duration will prolong by another 30–35 days.

On the applicability of some existing tropospheric scintillation prediction models for Ikeja and Abuja, Nigeria

Tropospheric scintillation which causes rapid fluctuation of signal due to the turbulence in the atmosphere is of significance in satellite link budget design. Existing models that predict the intensity of scintillation such as Karasawa, International Telecommunication Union Radiocommunication (ITU-R) Sector, Otung, Van de Kamp and Ortgies are not appropriate for predicting scintillation intensity (SI) in Nigeria due to localization of the models to particular regions. The monthly average air temperature and relative humidity for Ikeja and Abuja, Nigeria, retrieved from the Nigerian Meteorological Centre data bank were used for the investigation. An elevation angle of 5° was used as look angle, antenna diameter of 0.3 m, 40 GHz and 45 GHz frequencies were considered in this study. The existing scintillation model values were then compared with the measured values for the two locations to determine the best performance model. The SI results at 40 GHz and 45 GHz were obtained for each of the existing models. It could be deduced from the results obtained that orgies model values were the most closet to the measured values. Therefore, Orgies-N model was the most appropriate for SI prediction in Ikeja and Abuja.

Developing a Cold-Related Mortality Database in Bangladesh.

The aim of this study was to develop a database of historical cold-related mortality in Bangladesh using information obtained from online national newspapers and to analyze such data to understand the spatiotemporal distribution, demographic dynamics, and causes of deaths related to cold temperatures in winter. We prepared a comprehensive database containing information relating to the winter months (December to February) of 2009–2021 for the eight administrative divisions of Bangladesh and systematically removed redundant records. We found that 1249 people died in Bangladesh during this period due to cold and cold-related illnesses, with an average of 104.1 deaths per year. The maximum number of cold-related deaths (36.51%) occurred in the Rangpur Division. The numbers were much higher here than in the other divisions because Rangpur has the lowest average monthly air temperature during the winter months and the poorest socioeconomic conditions. The primary peak of cold-related mortality occurred during 21–31 December, when cold fronts from the Himalayas entered Bangladesh through the Rangpur Division in the north. A secondary peak occurred on 11–20 January each year. Our results also showed that most of the cold-related mortality cases occurred when the daily maximum temperature was lower than 21 °C. Demographically, the highest number of deaths was observed in children aged six years and under (50.68%), followed by senior citizens 65 years and above (20.42%). Fewer females died than males, but campfire burns were the primary cause of female deaths. Most mortality in Bangladesh was due to the cold (75.5%), cold-triggered illness (10.65%), and campfire burns (5.8%). The results of this research will assist policymakers in understanding the importance of taking necessary actions that protect vulnerable public health from cold-related hazards in Bangladesh.

Effects of Exposure Duration and Exposure Levels of Ambient Air Pollutants on the Risk of Polycystic Ovarian Syndrome: A 2015-2019 Korean Population-Based Cohort Study.

Exposure to ambient air pollution is associated with an increased risk of menstrual disorders and infertility. This study examined the relationships between the levels and duration of air pollution exposure and the risk of polycystic ovarian syndrome (PCOS) using Korean population-based cohort data (2015–2019). Real-time data on PM10, PM2.5, O3, CO, SO2, and NO2 were provided by the Korean Ministry of Environment. The average monthly air pollutant concentration from 1 January 2014 to 31 December 2018 was analyzed. To assess individual-level exposure to air pollutants, a spatial prediction model and an area-averaging approach were used. In total, 237,582 PCOS cases were analyzed. The annual age-adjusted PCOS incidence was 6.70, 8.28, 9.73, 11.58, and 11.97% from 2015–2019, respectively. The PCOS risk increased 1.29–1.32, 1.43–1.52, and 1.32-fold following exposure to the 2-year and 3-year average levels of PM2.5, O3, and NO2, respectively, compared to their 1-year average levels. The PCOS risk increased 1.75-fold (95% confidence interval: 1.66–1.85) in the fourth-quartile for the NO2 level. Increased SO2 and CO levels in the second- and third-quartiles were also associated with an increased PCOS risk. Exposure to air pollutants thus increased the risk for PCOS in the Korean population.

Epidemiological characteristics of severe fever with thrombocytopenia syndrome and its relationship with meteorological factors in Liaoning Province, China

BackgroundSevere fever with thrombocytopenia syndrome (SFTS), one kind of tick-borne acute infectious disease, is caused by a novel bunyavirus. The relationship between meteorological factors and infectious diseases is a hot topic of current research. Liaoning Province has reported a high incidence of SFTS in recent years. However, the epidemiological characteristics of SFTS and its relationship with meteorological factors in the province remain largely unexplored.MethodsData on reported SFTS cases were collected from 2011 to 2019. Epidemiological characteristics of SFTS were analyzed. Spearman’s correlation test and generalized linear models (GLM) were used to identify the relationship between meteorological factors and the number of SFTS cases.ResultsFrom 2011 to 2019, the incidence showed an overall upward trend in Liaoning Province, with the highest incidence in 2019 (0.35/100,000). The incidence was slightly higher in males (55.9%, 438/783), and there were more SFTS patients in the 60–69 age group (31.29%, 245/783). Dalian City and Dandong City had the largest number of cases of SFTS (87.99%, 689/783). The median duration from the date of illness onset to the date of diagnosis was 8 days [interquartile range (IQR): 4–13 days]. Spearman correlation analysis and GLM showed that the number of SFTS cases was positively correlated with monthly average rainfall (rs = 0.750, P < 0.001; β = 0.285, P < 0.001), monthly average relative humidity (rs = 0.683, P < 0.001; β = 0.096, P < 0.001), monthly average temperature (rs = 0.822, P < 0.001; β = 0.154, P < 0.001), and monthly average ground temperature (rs = 0.810, P < 0.001; β = 0.134, P < 0.001), while negatively correlated with monthly average air pressure (rs = −0.728, P < 0.001; β = −0.145, P < 0.001), and monthly average wind speed (rs = −0.272, P < 0.05; β = −1.048, P < 0.001). By comparing both correlation coefficients and regression coefficients between the number of SFTS cases (dependent variable) and meteorological factors (independent variables), no significant differences were observed when considering immediate cases and cases with lags of 1 to 5 weeks for dependent variables. Based on the forward and backward stepwise GLM regression, the monthly average air pressure, monthly average temperature, monthly average wind speed, and time sequence were selected as relevant influences on the number of SFTS cases.ConclusionThe annual incidence of SFTS increased year on year in Liaoning Province. Incidence of SFTS was affected by several meteorological factors, including monthly average air pressure, monthly average temperature, and monthly average wind speed.Graphical

Distribution of air temperature in the territory of Ukraine against the background of current climate changes

Monitoring climatic studies of the territory helps us to establish the peculiarities of the temperature regime, to find out the indicators of the frequency and intensity of extreme weather phenomena, inherent in modern climatic conditions. The study of their trends and the variability of spatial-temporal features remain a priority area of hydrometeorological scientific and practical research. The aim of the article is to study the patterns of air temperature distribution in the territory of Ukraine for two thirty-year periods (1991-2020, 1961-1990). Main material. World and domestic research results of modern climatic conditions indicate significant warming processes observed in all seasons. Significant climatic changes for the studied territory are gaining faster pace, causing a number of problems in the socio-economic sphere, which have an impact on the country’s food security. Established trends of climatic time series of average monthly air temperature throughout the year and seasons at twenty-five meteorological stations recorded transformations of regional temperature conditions at the end of the 20th - beginning of the 21st centuries (1991-2020). Such trends in the variability of the temperature regime of the territory directly lead to further additional studies of the local and regional climate, forecasting strategies for prevention and adaptation to probable changes. The analysis of average monthly air temperature indicators during the year for the periods 1961-1990 and 1991-2020 records a warming that covers all the presented weather stations. Conclusions. The results of the study establish a steady trend towards warming of the regional climate during the period 1991-2020, drawing attention to measures of adaptability to it, further study and forecasting of climatic indicators. A feature is the rate of warming, characterized by significant growth rates, reflected in the restructuring of the regional climate and the global climate system.

Climatic influence on productivity of walking excavators and bulldozers in stripping in gold placer mining

The state and mineability of placer gold reserves and resources in the Russian Federation is reviewed. Judging from wide application of dragline excavators in peat cutting, it can be effective to use draglines in placer mining at depths up to 50 m due to the much lower cost of stripping compared to the other methods. In this case, it is possible to apply various schemes of direct dumping and wider employment of draglines in actual mining. It is noted that one of the highest influences on productivity of draglines and bulldozers during stripping is the presence of seasonal and perennial frost. Two groups of factors to decrease productivity of walking excavators and bulldozers at negative air temperatures are proposed. The conclusions are made about the difficulty of determining frozen ground cuttability due to the peculiarities of overburden sediment formation and because of deficient detailed studies into the properties of rocks, which govern their strength characteristics during freezing. The less labor-intensive method of calculating productivity reduction of walking excavators and bulldozers during stripping is proposed as the determination of hourly productivity reduction patterns by mathematical methods describing the random nature of phenomena, in particular, by the correlation method. The equations of the hourly productivity reduction of draglines and bulldozers depending on average monthly negative air temperature and the hourly capacity reduction factor as function of seasonal permafrost thickness and perennial permafrost cross-sections in overburden face are derived. It is noted that seasonal freezing governs reduction in productivity of excavators and bulldozers at the beginning of the warm period of the year until the permafrost is completely thawed. Stefan&rsquo;s formula is suggested, according to which it is possible to calculate the depths of seasonal freezing of peat depending on the average monthly air temperature quite reliably.

Factorial analysis of taste quality and technological properties of cherry fruits depending on weather factors

The results of researching the fund formation of dry soluble substances, sugars, and titrated acids in cherry fruits of 10 studied varieties under the Southern Steppe Subzone of Ukraine are given. According to the content of biochemical quality indicators, the following varieties were selected: Modnytsya (the content of dry soluble substances is 17.1%), Ozhidaniye (the content of sugars is 11.7%), and Solidarnost (the content of titrated acids is 1.79%). The cherry fruits units. By conducting a two-factor dispersion analysis, the feasibility of forecasting the content of the principal components of the chemical composition (dry soluble substances, sugars, titrated acids) in the cherry fruits was determined by average values and a factor that maximally impacts the accumulation of the studied indicators was identified during the studies. The dominant influence of weather conditions during research years was determined. Therefore, the taste qualities of the cherry fruits were proposed to forecast by average varietal value. The average and strong correlation dependences of influencing 19 weather factors on the content of the studied biochemical indicators in the cherry fruits were determined. The accumulation dependence models of dry soluble substances, sugars, and titrated acids were built based on the principal component and least-squares methods. The first-rank weather indicators with the maximum influence particles were identified for the studied biochemical quality indicators. The average monthly air temperature in June maximally impacted the fund accumulation of dry soluble substances in the cherry fruits (delta = 9.9%), the content of sugars - the average monthly precipitation in June (delta = 8.5%), on the content of titrated acids - the total number of precipitation days in June (delta = 18.62%). At the end of the flowering phase before fruit ripening and in the last month of fruit formation, humidity indicators had the greatest influence on the accumulation of the studied biochemical indicators in the cherry fruits (June).of Melitopol purpura and Modnytsya have maximum indicators of the sugar-acid index in the range of 8.9-9.3 relative

Experience in construction of monolithic layers of road pavement at sub-zero air temperatures

Introduction. Increasing the durability of road structures and extending the construction season for the installation of monolithic road pavements are urgent tasks. Non-rigid road pavements are of particular interest. Replacing the bases of granular materials (crushed stone, gravel, etc.) with monolithic ones reduces the material consumption of the road surface by 20-50%, the cost of construction works by up to 45% and increases the service life of roads by 1.5-2 times. The extension of the construction season for the installation of monolithic bases contributes to an increase in the pace of construction, a more rational use of road construction equipment, securing highly qualified specialists at the enterprise and reducing overhead costs. A multi-tonnage waste having independent binding properties is of particular interest, for example, belite sludge of alumina production. The article is devoted to a comprehensive study of the physical mechanical and technological properties of natural belite sludge in order to use it for the making of monolithic layers of road and airfield pavement in winter, without the introduction of antifreeze additives.Materials and methods. The freezing temperature of the belite sludge of minus 2 ° C was determined by the thermoelectric method. Its compactibility in the range of negative temperatures, the ability to restore the destroyed structure after re-compaction, the regularities of cooling of the material during technological operations for the construction of structural layers in winter are studied. The compaction was studied by pressing samples from sludge of optimal humidity, at its temperatures from 20 to minus 10°C. The study of the processes of structure formation of sludge and sludge crushed stone materials consisted in studying the kinetics of hardening of samples stored in climatic chambers that simulate changes in average monthly air temperatures in an annual cycle (from 20°C to minus 20°C) and in natural conditions (outdoors). In parallel, thermographic and electron microscopic studies of neoplasms in the hardening material were performed. To study the regularities of the cooling of the sludge layers, a laboratory experiment was conducted that simulates two-way (top and bottom) freezing of the material in a climatic chamber at temperatures of minus 10, minus 15 and minus 25°C.Results. A complex of unique physical chemical and technological properties of natural belite sludge has been identified, which consist in maintaining the initial density and activity after freezing, the ability of sludge and sludge crushed stone materials to harden at negative temperatures, a reduced freezing temperature of minus 2°C, good compaction in the range of negative temperatures (up to minus 6°C). The temperature and technological parameters of the sludge preparation for the production of works in winter are investigated. The regularities of sludge cooling in the technological process for the construction of structural layers in winter are studied. A technology has been developed for the making of monolithic layers of the road pavement made of belite sludge and crushed stone materials at negative air temperatures up to minus 20°C. The practical experience of the belite sludge use in the construction of roads in 2-4 road-climatic zones is summarized.

Modern climate warming impact on the population dynamics of the small ground squirrel (Spermophilus pygmaeus Pallas, 1778) (Rodentia, Mammalia) in the Ilmenno-Prideltovy region of the Caspian lowland

The influence of the global climate warming on the population dynamics of the small ground squirrel at the border of its range in the northern desert zone on the territory of the Ilmenno-Prideltovy landscape area of the Caspian lowland in 1945–2019 is considered. Data on the numbers of small ground squirrels and the average monthly air temperature in January–February at the Astrakhan weather stations for the last 75 years have been analyzed and statistically processed. It is emphasized that the abundance dynamics of the species is determined by a whole complex of natural and anthropogenic factors. At the same time, in desert conditions, the distribution of air temperature and precipitation by seasons and years is limiting for the small ground squirrel. The January–February temperature effect provoking the awakening of the small ground squirrel from hibernation is analyzed. The high January temperature, followed by the February cooling, led to the mass death of animals, which would subsequently negatively affect the phenology of the main phenomena in the life of this monoestral species, disrupt the population structure and lead to a decrease in the numbers of animals. Against the background of the low January air temperatures, the awakening of the small gopher took place in February–March, and the higher February temperatures provided optimal conditions for a simultaneous exit from hibernation and participation in the reproduction of all sex and age groups of small gophers. Such a combination of January and February air temperatures took place during 1960–1979, which contributed to the growth and preservation of a relatively high level of the species' abundance. The high temperatures of the 1980–2009 winter months provoked the early release of the animals from hibernation: the numbers of ground squirrels decreased and kept at a low level. Against the background of decreases temperatures of the 2010–2019 winter periods, the effect of stabilization of the small ground squirrel population and some increase in the density of the species was observed.