-This paper presents a study of the diurnal variability of CO2 and CH4 concentrations in the surface layer of the atmosphere. The analysis takes into account meteorological parameters under urban and background conditions of the Middle Urals for 2022-2024 using cluster analysis. Statistically significant groups of measurements reflecting typical and elevated greenhouse gas levels throughout the day are identified. Based on numerous samples of hourly average measurements collected over a 24-h period, two statistically significantly different classes of diurnal variability in greenhouse gas concentrations are identified. These classes are characterized by typical and elevated levels in the surface air layer. The main daily CO2 concentrations for the cluster with typical variability were approximately 417.18 ppm at urban site and 425.51 ppm at the background site during summer and 437.84 and 432.83 ppm, respectively, in winter. For the cluster of elevated CO2 concentrations, mean daily values reached 433.74 ppm (urban) and 454.32 ppm (background site) in summer and 469.51 and 454.32 ppm, respectively, in winter. For CH4, typical mean daily concentrations were 2.06 ppm (urban) and 2.00 ppm (background site) in summer and 2.10 and 2.06 ppm, respectively, in winter. Elevated mean daily CH4 concentrations were observed at 2.14 ppm (urban) and 2.06 ppm (background site) in summer, reaching 2.29 ppm and 2.16 ppm, respectively, in winter. A combined analysis of CO2 and CH4 concentrations with meteorological parameters in the surface layer revealed the conditions for the formation of elevated greenhouse gas concentrations, contributing to improved climate forecasts for the Middle Urals region.
-The results of continuous monitoring of surface CH4 concentration using cavity ring-down spectroscopy at the Cape Baranov Ice Base high-latitude station in 2015-2020 are presented. The average annual values, interannual increase, seasonal variation amplitudes, and the day of occurrence of annual maximums and minimums of methane concentration are calculated. The obtained results are compared with the data from other high-latitude stations-Barrow, Alert, and Pallas-and show good agreement. The average annual values exhibit an almost continuous increase in the CH4 concentration at all considered stations. A significant increase in the average annual CH4 concentration growth rate was recorded in 2020 for the Cape Baranov Ice Base and Alert stations (21.63 +/- 0.10 and 18.29 +/- 0.08 ppb/year, respectively). At all stations but Alert, the second period of maximum CH4 concentration can be distinguished; it occurs at the beginning of autumn, probably due to the influence of tundra ecosystems and forest fires. The first period falls on the winter months. Using the HYSPLIT trajectory model, areas of potential regional methane source were identified for the region under consideration. These include swamped tundra areas of the Taimyr Peninsula and Eastern Siberia, possible gas hydrate accumulations, and areas with developed industry.
—According to measurements obtained by interplanetary missions and the Hubble Space Telescope, the main outer part of Jupiter’s Great Red Spot vortex is anticyclonic, while its inner region undergoes cyclonic rotation. This allows us to view Jupiter’s Great Red Spot as a quasi-geostrophic formation composed of two embedded vortices. Such an embedded vortex structure is called a composite vortex. Thus, Jupiter’s Great Red Spot is an almost stationary baroclinic vortex inside a zonal flow which can be represented as a barotropic flow with shear. This paper examines the composite vortex configuration consisting of an outer stationary vortex and an inner unsteady vortex which weakly influences the behavior of the outer vortex boundary. The quasi-geostrophic approach within the f-plane approximation in a stratified atmosphere is used. This work develops the ideas laid down in (Arakelyan et al., 2026, in press) which examines a composite vortex consisting of two stationary embedded vortices. A comparison of the energy of the composite vortex in two variants—with stationary and nonstationary embedding—with the energy of a vortex without embedding revealed an important property. The energy of a composite vortex consisting of an outer stationary anticyclonic vortex and an inner nonstationary cyclonic vortex having little effect on the behavior of the outer vortex boundary turns out to be minimum among the energies of the aforementioned models. In particular, the energy of the composite model of Jupiter’s Great Red Spot proposed in this paper is less than the energy of a homogeneous vortex without embeddings, while the model of a stationary vortex composite formation demonstrates that its energy exceeds the energy of a homogeneous vortex without embeddings. Thus, the composite vortex proposed in this work is energetically more favorable than a composite stationary vortex (Arakelian et al., 2026, in press) or a homogeneous vortex without embeddings (Suetin and Zhmur, 2023).
—Numerical experiments with an increase in the intensity of anthropogenic CO2 emissions into the atmosphere ( E_CO_2,ant ) and its subsequent decrease have been performed with the Earth system model of intermediate complexity developed at the A.M. Obukhov Institute of Atmospheric Physics of the Russian Academy of Sciences (IAP RAS ESM). Depending on the specific experiment, the time scales of the initial increase and subsequent decrease in E_CO_2,ant varied in the range from 50 to 2000 yr. These calculations revealed a significant hysteresis response of some variables characterizing the state of the active land layer and the terrestrial carbon cycle. In most cases, the hysteresis at the global level corresponds to higher values on the initial branch of the trajectory of the system state change as compared to the corresponding value on the reverse branch at the same global temperature. The exception, however, is the soil carbon stock for which the sign of the difference in values on these branches varies for different time subintervals. Two groups of regions can be distinguished: on the one hand, areas of tropical and temperate forests; on the other hand, regions of tundra and boreal peatlands. In the first regions, an increase in the intensity of photosynthesis due to the accumulation of CO2 in the atmosphere leads to an increase in the carbon reserve in vegetation, in the burned area due to wildfires, and intensity of carbon dioxide emissions into the atmosphere from them. In tundra and boreal peatlands, the delay in the propagation of the thermal signal in the soil on both hysteresis branches leads to a delay in the response of the thermal state of the soil relative to changes in global temperature and to a lower value of soil carbon stock on the forward branch of the hysteresis curve as compared to the reverse branch. In all cases, hysteresis is most pronounced at time scales of ∼( 10^1 - 10^2) yr and becomes less pronounced at larger time scales. This should be taken into account when developing measures to prevent climate change and/or mitigate the effects of these changes.
—This research provides an analysis of the effect of aerosols on the atmospheric electric field based on measurements taken in an area with moving sands (Kalmykia) and over the steppe region in Rostov region. The increase in the concentration of dust aerosol over steppe territories upon the strengthening of wind due to the accumulation of negative charge on microparticles leads to a decrease in the value of the electric potential gradient (electric field strength). Such regularity turns out to be rarer for deserted territories. There are frequent cases when the increase in dust aerosol concentration proportional to the wind velocity inversely affects the increase in electric field strength. The relationships of relative humidity with the dust aerosol concentration and with the electric field strength are noted at separate time intervals during the day. Throughout the day, the trends in both temperature and relative humidity vary for profiles up to 40 cm above the surface in arid and steppe regions. For arid territories under conditions of intensive surface drying, several processes of different natures related to the transport of watered and dry dust aerosol can be identified, which influence the change in the electric field strength.
