A method of forecasting the heavy convective precipitation zones during the cold season

A method of forecasting the heavy convective precipitation zones is based on the computation of the Q-vector divergence and moist equivalent-potential vorticity in the layer from 925 to 700 hPa. The prognostic fields of meteorological parameters from NWP models in GRIB or GRIB2 codes are used for the computation. Presented are the results of the statistical analysis. The coefficients of linear regression are computed and the working equation for forecasting heavy convective precipitation zones during the cold season is derived. Analyzed are some heavy snowfalls in the central region of the European part of Russia.     

Detection of methane ebullition in shelf waters of the Laptev Sea in the Eastern Arctic Region

Doklady Earth Sciences -     

Rare-Earth Elements in the Atmospheric Precipitation of the City of Blagoveshchensk

The mineral composition, distribution and fractionation of rare-earth elements in dissolved and suspended forms (solid residue) of atmospheric precipitation were studied by analyzing the snow sampled over urbanized territory by the example of the city of Blagoveschensk. Electron-microscopic studies revealed the own minerals of rare-earth elements in dust aerosols. It is shown that the main sources of the atmospheric pollution by rare-earth elements were emissions of TPP (heat and power plants) and boiler houses. Contrasting geochemical anomalies of rare-earth elements were found in the snow cover of the city. The REE concentrations in the solid phase of snow are few orders of magnitude higher than those of the liquid phase. The snow solid phase provides insight into the REE behavior, because it directly reflects the impact of different anthropogenic sources. The characteristic feature of the REE distribution in the solid residue of snow is their LREE enrichment relative to MREE and HREE. The average HREE content is 10% of total REE. In the snow water–solid phase system, most samples show weak fractionation between LREE and HREE owing to the low total mineralization of the snow liquid phase and the small content of organic matter.     

Energy sources for diagenesis: Evidence from the Black Sea

Complex investigations of recent and Drevnechernomorian (ancient Black Sea) sediments from the outer shelf, continental slope, and deep-water basin of the Russian Black Sea sector have been carried out using samples collected during cruise of the R/V Professor Shtokman organized by the Institute of Oceanology of the Russian Academy of Sciences (March 2009) and expedition of “YUZHMORGEO” (summer 2006). Rates of the main anaerobic processes during diagenesis (sulfate reduction, dark CO₂ fixation, methanogenesis, and methane oxidation) were studied for the first time in sediment cores of the studied area. Two peaks in the rate of microbial processes and two sources of these processes were identified: the upper peak near the water-sediment contact is related to the solar energy (OM substrate of the water column) and the lower peak at the base of the Drevnechernomorian sediments with high(>1000 μM) methane concentration related to the energy of anaerobic methane oxidation. The neogenic labile OM formed during this process is utilized by other groups of microorganisms. According to experimental data, the daily rate of anaerobic methane oxidation is many times higher than that of methanogenesis, which unambiguously indicates the migration nature of the main part of methane.     

Estimating the Influence of Thermal Inertia and Feedbacks in the Atmosphere–Ocean System on the Variability of the Global Surface Air Temperature

Izvestiya, Atmospheric and Oceanic Physics - The modern climate of our planet is characterized not only by a trend caused by an increase in the concentration of greenhouse gases in the atmosphere,...     

Using the isentropic analysis for the operational short-range weather forecast

The software is described, developed within the meteorological geographical information system (GIS Meteo) technology, intended for the operational plotting of isentropic analysis charts. The study of atmospheric processes is carried out by the example of a concrete event, an unexpectedly heavy snowstorm in Moscow region on December 7, 2009. It is revealed that the potential vorticity anomaly formed over Moscow region favored the generation of cyclonic circulation in the lower troposphere and the ascent of the air being close to the saturation. According to the observation data, the precipitation was of convective type, although no convective instability was revealed. The study of the equivalentpotential vorticity evolution in the lower troposphere demonstrated the presence of conditional symmetric instability causing the development of the moist slantwise convection.     

Anthropogenic factor and methane emission on the East-Siberian shelf

Results of data analysis, based on measurement of atmospheric concentrations of methane in the shallow part of the East Siberian shelf (ESS) are presented in this work. It was shown that methane emission in the atmosphere is determined not only by natural factors, but is also sensitive to anthropogenic influences, like the engine mode of a ship. It was determined that the hydraulic impact, which occurs when starting a ship’s engine after drifting through a shallow, can induce a great methane outbreak in the atmosphere. The power of these “short-lived” sources can exceed the power of any one deep-water mud volcano. In the shallow parts of the ESS, the anthropogenic factor can be one of the important factors effecting methane outbreaks in the atmosphere.