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The spatial and temporal variability of the main climatic indicators on the territory of the Volga Federal District in the 20th–21st centuries is considered. A general increasing trend in air temperature is revealed, and a heterogeneous pattern of precipitation changes is shown. The temperature variations until the end of the 21st century are analyzed on the example of Kazan using 40 CMIP6 climate models for four anthropogenic scenarios. In the paper, there is an assessment of the dynamics of agroclimatic resources on the territory of the Volga Federal District: the duration of the growing season, the sum of positive temperatures, total precipitation, and photosynthetic radiation. A correlation has been found between the temperature fluctuations in the region and the atmospheric circulation indices (NAO, AO, SCAND, and EAWR). For the territory of Tatarstan, a degree of aridity and waterlogging is evaluated using the agroclimatic indices: the Budyko's dryness index, the Selyaninov's hydrothermal coefficient, the Sapozhnikova's moisture index. It is shown that there is a tendency toward an increase in the duration of the growing season, its heat supply and aridity in the region in summer. A statistical estimation of the dependence of spring wheat yield on the agroclimatic indices on the territory of the Republic of Tatarstan is given. [ABSTRACT FROM AUTHOR]

In the paper, the frequency and spatial distribution of atmospheric and hydrological droughts over the territory of Belarus in 1945–2020 is assessed. Aridity is evaluated using the standardized precipitation and streamflow indices (SPI and SSFI). Trends in monthly total precipitation are determined, the features of the streamflow formation during the open-channel period are revealed. The frequency of anticyclones that determines hydrometeorological conditions on the territory of Belarus is calculated. The statistically significant increase in the number of the days with anticyclonic weather over the country during the warm season is found. The increasing frequency of dry conditions in summer months against the background of a rise in the precipitation intensity is highlighted. A simultaneous increase in the frequency of very-low-flow periods on rivers and an increase in the height of warm rainfall floods in some river basins are revealed. [ABSTRACT FROM AUTHOR]

The overview of papers dealing with the analysis of current and future climate change on the territory of Russia and their impact on the crop productivity is presented. Using the reanalysis data for 1950–2020, trends in air temperature and precipitation are estimated for different regions of Russia. A correlation was found between changes in temperature and atmospheric circulation indices. [ABSTRACT FROM AUTHOR]

Modern methods and technologies for operational automatic classification of cloud cover and precipitation parameters using visible and infrared data from satellite multi-channel scanning radiometers are considered. The paper analyzes threshold classification techniques and algorithms based on machine learning and artificial neural networks and the results of validation of satellite products obtained from the comparison with ground-based meteorological observations and independent satellite estimates. Problems and prospects of further development and application of cloud clover and precipitation monitoring are formulated. [ABSTRACT FROM AUTHOR]

This paper continues the research started in [4] that investigates the thundercloud with hail observed over Saint Petersburg on July 22, 2017. The results of numerical simulation of the cumulonimbus cloud using a small-dimensional model are presented. The spatiotemporal variations in the updraft velocity, liquid water content, ice water content, volume charge density, electric field strength, and other parameters are studied. Two cases are simulated and intercompared: without and with the heterogeneous cloud droplet freezing. It is shown that the formation of precipitation including hail occurs more intensively in the second case. Special attention is paid to the simulation of cloud electric structure, which was performed in combination with the modeling of its dynamics and microstructure. It is demonstrated that the most powerful cloud electrification processes occur due to the interaction between cloud and precipitation particles (hailstone–ice crystal, melting hailstone–cloud droplet, raindrop–cloud droplet). The dynamics of the cloud electric structure at different life stages is modeled. [ABSTRACT FROM AUTHOR]

The paper studies the connection between the precipitation regime over the northern Baikal mountain region during the warm season (April–October) and atmospheric macrocirculation processes, the results are presented. Based on the data of ten weather stations, spatiotemporal heterogeneities in the precipitation regime are revealed for the period of 2000–2018. The long-term (since the middle of the 1960s) trends in total precipitation are evaluated. According to the analysis of HYSPLIT five-day backward trajectories (for days with precipitation), the main directions of moisture transport to the study area are identified, and the trajectories are typed for each month. Three groups of atmotpheric macroprocesses which induce precipttation are identified, and the contribution of each group to total precipitation is estimated. The spatial distinction between different parts of the study area in the precipitation regime and predominant moisture sources is found. [ABSTRACT FROM AUTHOR]

The paper analyzes long-term changes in the water inflow to Lake Baikal which have occurred since the early 20th century and have been transformed due to the global warming intensification since the 1970s. The differences in distribution parameters and in the values of the inflow of estimated probabilities are studied for the full series and for its two parts divided as of1971. The revealed increase in the wintertime inflow is caused by the cold period duration reduction and by the permafrost degradation resulting from the air temperature rise. Since 1996 inflow has decreased, which is associated not only with precipitation reduction but also with evaporation increase. The Selenga River, the largest tributary of Lake Baikal, demonstrates the greatest decrease in runoff among the Baikal rivers. [ABSTRACT FROM AUTHOR]

To elaborate a complete model of the Earth system, it is necessary to include the model of dynamics of Greenland and Antarctic ice sheets into the General Circulation Model (GCM). The problem is that spatial and temporal scales of ice sheet dynamics, on one hand, and the dynamics of atmosphere and the ocean, on the other hand, differ considerably. In order to unite them in one model, implementation of one or another downscaling procedure is required. For this purpose we elaborated an energy- and water balance model of the Greenland ice sheet (EWBM-G) serving as a buffer between the GCM INMCM and the ice sheet model. EWBM-G describes heat and water vapor diffusion in a limited domain with the boundary conditions transferred from the INMCM. This paper describes the model and set-up of the numerical experiments aiming at calculation surface air temperature and annual precipi-tation amount in Greenland in accordance with the simulated pre-industrial climate. The results of calculations are compared with observations and reconstructions. [ABSTRACT FROM AUTHOR]