Vol 43, No 5 (2018)

The dynamic coupling between the stratospheric and tropospheric processes is studied for the sudden stratospheric warming registered in January-February 2017. Also, the effects of these processes on the tropospheric circulation and weather conditions in the middle and high latitudes via the reflection of wave activity from the stratosphere are investigated.

A complex approach is considered to the estimation of emissions of carbon gases formed during wildfires in the middle taiga subzone in the Yenisei region of Siberia. Based on the large-scale Siberian wildfires in 2012, the relative contribution of emissions to the values of background concentration of carbon gases (CO₂, CH₄, CO) in the atmospheric boundary layer measured at the 300-m ZOTTO tall tower is assessed. The degree of ecosystem damage caused by wildfires is estimated depending on their intensity and combustion phase (flame or flameless). Emission factors are calculated for the major carbon gases in wildfire plumes which are the key component for assessing wildfire emissions to the atmosphere.

The iceberg drift model is developed and used for simulating the iceberg drift trajectory in the Barents Sea. The model is forced by hydrometeorological characteristics obtained from ship observations. Original techniques for retrieving the sea-level slope gradient and surface velocity of currents are proposed, implemented, and validated using independent data. Thus, additional data were calculated from field data in order to use the iceberg drift model with the full set of external forces. This allowed improving the iceberg trajectory simulation and assessing the contribution of all forces that affect the iceberg drift. The iceberg drift calculations demonstrate that the drift characteristics are extremely sensitive to all external effects and the model parameters; therefore, the quality of input hydrometeorological data essentially affects the simulation of real iceberg trajectories.

The results of long-term biogeochemical monitoring of Lake Baikal are presented. The accumulation is studied of polycyclic aromatic hydrocarbons (PAHs) in bottom sediments and macrozoobenthos that were synchronously sampled at the same stations. The stations are located in the areas where anthropogenic impact on the lake is high: in the area of the former Baikal Pulp and Paper Mill (BPPM), in the footprint of the BAM railway in the north of the lake and in the Selenga River delta front as well as in the zones of coastal fouling in the area of BPPM. It is found that variations in the concentration of PAHs in macrozoobenthos do not directly depend on those in the sediments. It is revealed that the maximum concentration of benzo[a]pyrene in the area of the former BPPM is almost by eight times higher than in the other areas of the lake; shallow-water macrophytes accumulate more polyarenes than deep-water macrozoobenthos.

The review is based on the operation results of the system that monitors the total ozone (TO) in the CIS and Baltic countries and functions in the operational mode at the Central Aerological Observatory (CAO). The monitoring system uses the data from the national network equipped with M-124 filter ozonometers working under the methodological supervision of the Main Geophysical Observatory. The quality of the system functioning is operationally controlled in CAO by the comparison with the observations obtained from the OMI satellite equipment (NASA, USA). Basic TO observation data are generalized for each month of the first quarter of 2018 and for the first quarter. The data of routine observations of surface ozone values in the Moscow region and Crimea are also considered.