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Since modern research indicates climatic changes in all regions of our planet, including on the territory of Ukraine (in particular, the deviation of temperature and other meteorological parameters from the values of the climatic norm), their study is extremely important. After all, they can lead to changes in the nature of precipitation distribution, the length of the growing season, a decrease in the duration of the stable snow cover, local runoff water resources, etc. Most scientific works in recent years describe changes in the distribution of temperature characteristics and precipitation regime, because they are one of the main indicators of the state of the climate system. Therefore, the purpose of this article is to identify the features of changes in air temperature and precipitation for the entire territory of Ukraine from 2021 to 2050 based on the results of 16 simulations of the ensemble of CORDEX models based on the RCP4.5 scenario. The CORDEX project is a modern simulation of the future climate and has a resolution of ~ 12.5 km in the horizontal plane, which makes it possible to better simulate the characteristics under study. It integrates regional climate predictions that are generated using statistical and dynamic methods. The results obtained are presented for 177 cities of Ukraine, which currently form the basis of a modern monitoring network. It was found that the number of days with precipitation ≥ 5 mm in transitional seasons increases on average by 1-3 days per month, depending on the region. The maximum values of the frequency of occurrence of the number of days with precipitation ≥ 5 mm are observed in the west and gradually decrease in the south. Compared to 1961-1990, the most significant changes occur with the number of frosty days with an air temperature of ≤ 0°С, which noticeably decreases during the study period from north to south. In April and October, for the southern regions of Ukraine, the considered parameter is equal to 0, which means that in these months the air temperature for these regions will have positive values. From the above, there is a tendency towards warming in transitional seasons and a change in the nature of moisture supply to the territory of Ukraine in the next thirty years.

The aim of the study is to determine statistical estimates for the distributions of average monthly and annual temperatures, as well as monthly and annual precipitation for the North-Western Black Sea coast during the climatic change intensification epoch. Parameters of the normal distribution for temperature, two- and three-parametric gamma distribution for precipitation, as well as trend characteristics, are analyzed. To determine the deviation of the values from the previous climatic period, the data of the Climate Cadastre of Ukraine (1961–1990) were used. The results of the statistical analysis show that steady trend towards an increase in annual air temperatures exists at all stations during the period (2000-2018). In the time course of these characteristics, there is a clearly pronounced separation into two periods with the transition point in 2007. The average monthly air temperatures for the period generally exceed the same values for 1961-1990, and this is especially evident for the summer months. Time distributions of monthly precipitation are spatially heterogeneous. It was found for Odesa that the maxima are observed in January, July and September, in contrast to other stations, at which the maximum amount of precipitation is registered in the summer months. Also, at the Odesa, the monthly precipitation in most months exceeds the same values for 1961-1990. Annual precipitation during 2000-2018 has a lot of regularities and differences, among which, for example, a common feature is the presence of maxima in 2010. In accordance with the general period trend characteristics, a tendency to an increase in the annual precipitation was found in the very south (Izmail station) only, and it has been especially pronounced since 2009. However, their mean values are lesser than in the Climate Cadastre of Ukraine; this is also observed for the stations Lyubashivka and Mykolaiv. On the contrary, at stations located on the coast (Odesa, Ochakiv), the annual precipitation exceeds of values from the Cadastre. Based on the analysis carried out, it can be concluded that all persistent tendencies to changes in the values of the considered climatic characteristics are associated with a possible change in the atmospheric circulation over the considered territory.

Global temperatures over the period of 2081–2100 are expected to rise by 0.3–4.8 °C compared to the period of 1986–2005. According to the previous studies, the average annual air temperature in all regions of Ukraine will keep increasing in the near future and the maximum increase in precipitation is expected mainly in the western and northern regions during winter and spring, whereas the decrease in precipitation will be registered in the central, eastern and southern regions during summer and autumn. This article aims to identify the features of changes in air temperature and precipitation for different regions of Ukraine in 2021–2050 based on the modelling results of the ensemble of CORDEX models as per the RCP4.5 scenario. 16 simulation runs for 7 regional climate models were selected for the analysis and the results were presented for five regional centers of Ukraine: Kyiv, Lviv, Kropyvnytskyi, Kharkiv and Odesa. It is shown that future monthly precipitation in all regions tends to increase by an average of 20–40 mm during autumn, winter and spring, whereas the decrease is expected to occur in summer. According to some models, the monthly precipitation will be close to zero in the Southern Ukraine in July and August, which is typical for the Mediterranean climate. Compared to the period of 1961–1990, the average monthly temperature will undergo small changes (up to 1 °C) in spring and autumn, while the temperature in summer and winter will increase by 2.5–3.5 °C. In Odesa, in contrast to the present-day situation, a positive average monthly air temperature will be expected to be recorded throughout the whole year, and only 25% of the runs show negative average monthly minimum temperatures. In the Northern Ukraine, the average monthly minimum and maximum temperatures in winter will increase by 2.0–2.5 °C, and in summer only the maximum air temperature will increase significantly. Thus, we can assume a change in the regime of moisture supply in Ukraine over the next thirty years. One can also assume a high probability of snow cover absence throughout the whole winter in the Southern Ukraine as a result of positive temperatures.

The topicality of the study is stipulated by the need to diagnose, monitor and predict the weather conditions causing temperature anomalies in Ukraine in order to prevent their adverse impact on the country's economy. On the climate change background, extreme weather events become more frequent and intense. The forecast for anomalous events can be significantly improved if the main types of atmospheric circulation related to those events will be identified. This paper aims to identify the main circulation processes causing the initiation of hot and cold weather conditions in Ukraine. These conditions are the so-called indices of extremes: summer days (SU), tropical nights (TR), ice days (ID), and frosty days (FD), calculated using the daily minimum and maximum air temperature at the regular grid points covering the territory of Ukraine with a spatial resolution of 0.75×0.75 degrees. The GWL circulation types were obtained from the Hess-Brezovsky objective classification for the atmospheric processes, which is widely used for synoptic analysis in Europe. The GWL circulation types differ by the location of ridges (anticyclones) and troughs (cyclones) on the 500 hPa isobaric surface. The difference from most other atmospheric circulation classifications is that each GWL remains for at least 3 days. If the transition to another GWL lasts more than 1 day, such days are considered as the previous or next GWL, whichever is most similar. The frequencies for ten types of weather patterns by the Hess-Brezovsky classification for the period from 1971 to 2001 were analyzed for Ukraine, and the circulation types, which are the most common for summer days, tropical nights, frosty days and frosty nights, were detected. It was shown that the extreme hot or frost weather conditions are in most cases initiated by the same circulation type. Also, the initiation of hot and frost weather is almost completely unaffected by the weather pattern caused by the third, fifth and ninth types of the GWL classification.

Introduction. The Moroccan energy system is highly dependent on external energy markets. This is why the current Moroccan energy strategy is focused on deployment of renewable technologies projects. Morocco has abundant wind resources. The purpose of this publication is identifying the characteristics of wind regime in Tangier in 2021-2050 to assess the wind potential. Results. This particular study used the data of regional climate modelling (RCM) with high spatial resolution of the CORDEX project. The article contains the results of RCM modelling using the RCP 4.5 scenario presented in the rectangular coordinate system with spatial resolution of ≈ 44 km. An ensemble of 11 climatic models was used for the analysis. To verify the RCM retrospective simulations for the period of 2011-2016 were used and to verify the RCM forecasts associated with wind speed we used the observations made at the Tangier meteorological station. The performed analysis allows us to conclude that average ensemble-based series of average monthly values are close to average values of the observed meteorological parameters. The models reflect the climatic parameters with varying degrees of accuracy and their results can be used to analyze future conditions of the climatic system in this region. Average wind speed for the period of 2021-2050 at the Tangier station will be equal to 5.1 m/s which exceeds the current value of 0.6 m/s. According to the forecast the wind speed in the territory of Tanger – Tetouan − Al Hoceima region will exceed 4.5 m/s. Comparison of the RCM-calculated wind speed value with the observational data for the period of 2005-2014 showed its increase. Based on the average annual wind speed values in each of the grid's nodes the linear regression coefficients were calculated. Conclusion. RCM-modelling showed that in 2021-2050 the territory of Tanger – Tetouan − Al Hoceima region will be dominated by the conditions being favourable for operation and further development of wind energy. Comparison of model calculations with observational data of the current climatic period showed that the Strait of Gibraltar area and the adjacent territories will see the wind speed increase in the future. The maximum value of wind speed annual run will be observed during the cold period of the year which coincides with the period of increased demand for electricity by its consumers. Directions of further research. The results of this study will be used as the basis for calculating the wind power in this region in 2021-2050.

The Moroccan energy system is highly dependent on external energy markets. The use of solar energy is one of the most promising ways in the development of renewable energy sources. At the moment, there are several scenarios for the development of renewable energy in Morocco diverging only in quantitative assessments. All of them are aimed at increasing the generation of green energy, from the complete satisfaction of all needs of Moroccan consumers to the opportunity of exporting some of its environmentally friendly electricity to Europe. Estimation of energy efficiency of solar installations is usually carried out on the basis of calculations of solar radiation arrival in the presence of cloudless sky. Clouds significantly reduce amount of solar radiation and sunshine duration. This study is aimed at determination of possible quantitative parameters of the total cloud cover and the areas in which the cloud cover would have the least impact on the amount of incoming solar radiation in Morocco in 2020-2050. The article presents the results of simulation of total cloud fraction using 11 regional climate models of CORDEX project for the period of 2020-2050 in Morocco. For the period of 2020-2050 the average values of total cloud fraction on the territory of Morocco will have the smallest values within the plains located near the border with Algeria on the territory of the prefecture of Sous-Massa lying at the foot of the southern slopes of the Anti-Atlas. The analysis of the annual regime of total cloud fraction showed that in the future it will be of a different nature in different parts of the country due to various factors affecting its formation. The area with the smallest volumes of monthly total cloud fraction will lie within the territory the southern part of prefecture Draa-Tafilalet and prefectures Sous-Massa, Guelmim-Oued Noun, Laayoune-Sakia El Hamra, Dakhla-Oued Ed-Dahab excluding their coastal parts of the Atlantic Ocean. In the future most of the territory of Morocco will be characterized by a low amount of total cloud fraction, which, in its turn, will have an insignificant effect on the amount of solar radiation entering to the underlying surface of these areas. In terms of solar power, the best conditions will exist at the southern parts of Morocco, excluding the coast where the total cloud fraction will have the least impact on the amount of solar radiation reaching the earth’s surface and on sunshine duration.

The paper analyzes spatiotemporal features the indices of hot, cold and precipitation that are related to weather conditions. The temperature in Ukraine tends to be higher, which is the main regional feature of global climate changes. The North Atlantic Oscillation had an influence on the precipitation in Ukraine – weather is rainier during its negative phases. Also, colder night and hotter days were more frequent during negative phases of the NAO. This fact can be explained by enhancing meridional flows in Ukraine. The wavelet analysis also revealed an impact of the NAO on temperature anomalies – positive phases determined increasing monthly minimum temperatures before the 1980s and decreasing ones after 1980s. Also, the wavelet analysis showed that the Nor-th Atlantic Oscillation influenced the precipitation in northern and southern parts of Ukraine in different ways.

The mechanical properties of weighted drill pipe and kellys made of silicon-manganese steel 36G2S of strength group ''K'' were analyzed by the method of mathematical statistics to determine the reasons for the low quality of the pipes. The analysis showed that the ranges of values for the contents of C, Mn, and Si exceed the prescribed composition range for this steel. The feasibility was studied of replacing steel 36G2S by chromium steel 40KhF. The mechanical properties of pipes rolled from heats of steel 40KhF met the specifications for strength group ''K''. Rejects and waste were reduced by 15% and the consumption coefficient was also reduced.