VARIATIONS IN THE KARA SEA LEVEL, THEIR STERIC FACTORS, AND SOLAR RADIATION DURING 1993-2018

The GLORYS12v.1 and ERA5 reanalyses for different months are used to study a relationship between long-term variations in the monthly mean values of sea level in different areas of the Kara Sea and their steric factors during 1993-2018. The areas of the sea were identified where the relationships between these changes and variations in the mean temperature and salinity of the upper quasihomogeneous water layer, as well as the variations in the monthly mean intensity of their insolation, are statistically significant.

INVESTIGATION OF RADAR AND ELECTRICAL CHARACTERISTICS OF THUNDERCLOUDS SEEDED WITH A GLACIOGENIC REAGENT IN KARNATAKA, INDIA

Characteristics of developing convective clouds (Cu) in Karnataka state (India) during the thunderstorm formation are analyzed using weather radar and lightning detection network data. It is noted that radar characteristics of Cu which produced lightning, exceed those where lightning does not form. The study has shown that the number of negative cloud-to-ground strokes exceeds the number of positive ones by an order of magnitude. The radar characteristics of clouds in India and the North Caucasus are compared. Significant differences in lightning flash rates over the mentioned regions are registered. A low correlation is found between the supercooled volume and the flash rate of negative lightning. The paper also presents the results of studying the dynamic characteristics of four Cu seeded with a glaciogenic reagent. The thunderstorm risk is estimated for the clouds. It is shown that the seeding increases a probability of lightning events.

HYDROCHEMICAL STATE OF RIVERS IN THE SEMI-DESERT ZONE OF THE EAST EUROPEAN PLAIN (THE ERUSLAN RIVER BASIN, THE LOWER VOLGA)

The results of the assessment of the hydrochemical state of the plain rivers of the Yeruslan basin flowing in the semi-desert region of the Russian Plain are presented. The priority pollutants that most often exceed the MPC for fisheries-related water bodies are: organic matter, total phosphorus, copper, and nitrite nitrogen. In some areas of small rivers, there is a very high level of contamination with trace elements such as copper (up to 80 MPC) and manganese (up to 38 MPC). The conducted studies, taking into account the literature data, allow us to assert that the pollution of rivers is chronic and is largely due to the peculiarities of the hydrogeological conditions of the territory.

PARAMETERIZATION OF SHORT-WAVE SOLAR IRRADIANCE FOR GLACIOLOGICAL APPLICATIONS

Solar irradiance is the most important factor which determines the thermal conditions of mountain glaciers. We use trigonometric formulae to calculate direct solar radiation incoming on any arbitrary oriented surface under the condition of absence of the atmosphere. Shading effect from the surrounding relief can also be evaluated rather precisely. Nevertheless, in order to obtain correct results, it is necessary to take into account atmospheric transmissivity, diffuse radiation, and influence of cloudiness. The paper presents a model for calculation of shortwave radiation, utilizing up-to-date data on the atmospheric composition and schemes for parameterization of the atmospheric transmissivity, which have never been implemented in glaciological applications before. Validation of the model was carried out using observational data on the global radiation on two weather stations established on Karabatkak glacier (Inner Tien Shan).

HOW CHINA ATTEMPTS TO VANQUISH AIR POLLUTION IN THE 21ST CENTURY

In February 2012 a war has been declared by the Chinese government against the nagging air pollution, which takes a mounting death toll annually. The three-pronged national-scale regulations of afforestation/silviculture, ultra-low emission, and energy structure reform have been carried out firmly by authorities, etching the determination of the nation to implement the WHO’s recommended interim target of air pollution control. Undeniably, preliminary battle against air pollution has achieved initial success. Eight years after the declaration air pollution has been controlled to an acceptable level, compellingly demonstrating the validity of current policy, even with continued reasons for skepticism and gaps in scientic knowledge. However, the accruing trend of tropospheric O3 in the surface air and high level of wintertime PM2.5 signify this en masse war is far from winning.

OZONE CONTENT OVER THE RUSSIAN FEDERATION IN THE SECOND QUARTER OF 2021

The review is compiled on the basis of the results of the operation of the total ozone (TO) monitoring over the CIS and Baltic countries functioning in the operational mode at the Central Aerological Observatory (CAO). The monitoring system uses data from the national network equipped with M-124 filter ozonometers that is under the methodological supervision of the Main Geophysical Observatory. The quality of the functioning of the entire system is operationally controlled at CAO by the comparison with the OMI satellite equipment observations (NASA, USA). Basic TO observation data are generalized for each month of the second quarter of 2021 and for the second quarter. Data of routine observations of surface ozone values in the Moscow region are also considered.

CALCULATION OF AIR QUALITY INDEX AND ASSESSMENT OF ITS INFORMATIVENESS FOR RUSSIA BASED ON MONITORING DATA FOR MOSCOW

An overview of methods for calculating air quality indices (AQIs) widely used abroad to provide the population with information on air quality is presented. Foreign AQIs are used in available mobile applications, in interactive global display of air quality, including the territory of the Russian Federation. In Russia, AQI has not yet been used to inform the population. Taking into account the principles of grading the classes of foreign indices, a scheme for calculating the Russian variant of the index AQI-R using Russian air quality standards is proposed. The comparison of AQI based on the European Union scheme (AQI-EU) and AQI-R calculated from observations in Moscow showed that according to the EU scheme, the air quality assessment is stricter and more often indicates poor air quality. The differences in the estimates are associated with excessive requirements for the concentration of PM10 and PM2.5 in the AQI-EU. For the development and adoption of the national AQI, it is necessary to take into account Russian priorities in assessing air quality and regional features of air pollution.

LONG-TERM CHANGES IN SOLAR RADIATION IN NORTHERN EURASIA DURING THE WARM SEASON ACCORDING TO MEASUREMENTS AND RECONSTRUCTION MODEL

A reconstruction model of surface solar radiation (SR) is developed. The results of reconstructing the interannual SR variability for the period of 1968-2016 are tested against the observations at MSU (Lomonosov Moscow State University) Meteorological Observatory for the warm season (May-September), the comparison showed a good agreement (the coefficient of determination R2 = 0.8). The analysis of temporal variations in SR over Northern Eurasia (40-80 N; 10 W-180 E) due to various factors revealed that in most cases there has been a trend toward an SR increase since 1979. In addition, it is demonstrated that the long-term SR variability over Northern Eurasia was effectively explained by variations in the cloud transmission of Sr, except for the polluted regions of Siberia and China and several stations in Northern Europe, where the aerosol factor dominates in some cases.

MICROCLIMATIC FEATURES OF SAND DUNES IN NORTHERN TAIGA IN WESTERN SIBERIA

Analysis of microclimate parameters on various elements of the mesorelief of natural sand dunes in the Nadym region of the Yamal-Nenets Autonomous Okrug showed that the elements of that mesorelief form individual combinations of meteorological elements of the microclimate: the maximum wind speeds are observed at the tops of the dunes, the maximum values of relative humidity and temperature are typical for leeward slopes. The condition of the plants growing on the dunes depends on the microclimatic conditions and temperature regime of the upper part of the sandy deposits. The transfer of sand by strong winds and significant freezing of the surface layer is a determining factor in preventing plant growth. The temperature and relative humidity of the surface layer of atmospheric air, which form special "greenhouse" conditions on the leeward slopes of the dunes, have a positive effect on the growth of vegetation, under the condition of insignificant wind loads.

ASSESSMENT OF ECOLOGICAL STATE OF WATER BODIES USING INTEGRAL HYDROBIOLOGICAL AND HYDROCHEMICAL INDICATORS

The paper considers the features of the joint use of hydrobiological and hydrochemical indicators to characterize the ecological state of water bodies. The comparison of effectiveness of the joint assessment of the state of aquatic ecosystems based on hydrobiological and hydrochemical indicators is carried out. In some cases, a discrepancy between the integral assessment characteristics was revealed. It is due to the fact that the comparison of data of the Roshydromet hydrochemical and hydrobiological monitoring is carried out at the same site not taking into account hydrological features of water bodies.