Vol 44, No 1 (2019)

The variability of Arctic total ozone in the winter of 2015/2016 is studied using the data of the national network equipped with M-124 filter ozonometers and satellite monitoring. The first ozone mini-hole that emerged in the first half-year over the whole history of observations (developed at the end of January 2016) is analyzed. The reasons for the total ozone variability over Russia in the first quarter of 2016 are analyzed, and the comparison with the significant Arctic ozone anomalies in 1996/1997 and 2010/2011 is presented.

The seasonal evolution of sea ice thickness in the eastern part of the Taganrog Bay is studied using the one-dimensional thermodynamic sea ice model. The numerical experiments are conducted to simulate the thermal evolution of sea ice thickness using various snow parameterization schemes. The results of modeling for the winters of 2007/2008 and 2008/2009 are compared with in situ observations. The quality of the forecast of seasonal variations in sea ice thickness is assessed.

The history of coastal catastrophic floods was reconstructed for the first time using the geochemical proxy in shelf sediments. The reconstruction is based on the identification of sediment layers accumulated on the shelf during the intensive discharge of the river runoff suspended matter from the land which does not contain bromine. The set of isotopic (AMS ¹⁴C, ²¹⁰Pb, ¹³⁷Cs), tephrastratigraphic, and paleomagnetic methods was used for the detailed chronology of sediments. The scanning of chemical composition of sediments with the step of 0.5–0.8 mm is performed using the synchrotron radiation X-ray fluorescence in the VEPP-3 storage of the Institute of Nuclear Physics of Siberian Branch of Russian Academy of Sciences. The history of catastrophic floods for the past 1800 years is reconstructed based on the typical variations in bromine concentration in one of the cores from the Amur Bay (the Sea of Japan). New methodological approaches to the flood signal extraction are proposed. The revealed inverse correlation between the frequency of floods caused by typhoons over the coast of the Sea of Japan and southern China agrees with the existing assumption on the change in their trajectories in different periods of global climate change.

The variations in the concentration of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in atmospheric air in the northern Lake Hovsgol region in 2008–2015 is analyzed using passive air sampling data. It was found that the concentrations vary from background values (comparable with those for other high-mountain regions) to the levels typical of large settlements. The quantitative and qualitative variations in the concentration of PCBs and OCPs in air are recorded. The variations characterize the influence of both natural (seasonal variations in temperature and average annual temperature anomalies over the land and sea across the globe and Northern Hemisphere) and anthropogenic factors. There is a trend towards the increase in hexachlorobenzene (HCB) levels and the decrease in hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) levels in the atmosphere. No significant variation in the total PCB was found in 2011–2015. The results of the modeling of PCB and OCP fluxes in the air-soil system in the analyzed region demonstrate that deposition prevails over volatilization that corroborates the significance of atmospheric transport for the PCB and OCP inflow to the Lake Hovsgol region.

Seasonal prediction and climate change modeling are carried out on the basis of the programs incorporating the global model of the atmosphere, ocean model, sea ice and land models, etc. Each component of a coupled model has to provide a fairly complete representation of the physical processes in the appropriate medium, while the other components are replaced by reanalysis data. In this paper we present the results of a study aimed at improving the quality of the climate simulation with the SL-AV global atmospheric model where both ocean sur face temperature and ice concentration are prescribed. We also discuss some probtems in tuning the parameterizations of subgrid-scale physical processes and their modifications.