A.V. Kislov

Atmospheric circulation and storm events in the Black Sea and Caspian Sea

Extreme sea storms are dangerous and a potential source of damage. In this study, we examine storm events in the Black Sea and Caspian Sea, the atmosphere circulation patterns associated with the sea storm events, and their changes in the present (1961–2000) and future (2046–2065) climates. A calendar of storms for the present climate is derived from results of wave model SWAN (Simulating WAves Nearshore) experiments. On the basis of this calendar, a catalog of atmospheric sea level pressure (SLP) fields was prepared from the NCEP/NCAR reanalysis dataset for 1961–2000. The SLP fields were subjected to a pattern recognition algorithm which employed empirical orthogonal decomposition followed by cluster analysis. The NCEP/NCAR reanalysis data is used to evaluate the occurring circulation types (CTs) within the ECHAM5-MPI/OM Atmosphere and Ocean Global Circulation Model (AOGCM) for the period 1961–2000. Our analysis shows that the ECHAM5-MPI/OM model is capable of reproducing circulation patterns for the storm events. The occurrence of present and future ECHAM5-MPI/OM CTs is investigated. It is shown that storm CTs are expected to occur noticeably less frequently in the middle of the 21st century.

Climate modeling results for the Circum-Pontic Region from the late Pleistocene to the mid-Holocene

Three-dimensional mathematical climate models (referred to as general circulation models or GCMs) have been used (1) to assess past and future climates under prescribed boundary conditions and (2) to determine climatic equilibrium responses to component changes. With geographic focus on the Circum-Pontic region, this paper examines the results of several GCMs for periods of extreme climate during the late Pleistocene and mid-Holocene. Climatic characteristics were prepared to simulate conditions during the Last Glacial Maximum (21 ky calBP/18 ky BP) and the Holocene warm event (6 ky calBP/5.3 ky BP). The results yield possible temperature and precipitation distributions for the times in question compared to those of today.

The Black Sea and the Caspian Sea paleolevel changes: links to simulated runoff of rivers and global climate change

Introduction To assess the link between climate variability and hydrological regime, we focused our study on the mid-Holocene (6 ka years BP) and the last cold period of the Late Quaternary (21 ka BP). We discuss how well current general circulation models (GCMs) can reproduce river runoff changes and, consequently, variations in closed lake level under contrasting climate conditions. The Paleoclimate Modeling Intercomparison Project (PMIP) (Joussaume and Taylor, 1995) has run simulations that are used in this study. The rivers of the East European Plane (EEP) were selected for analysis. Feed of rivers is determined by the balance of precipitation and evaporation in the catchment, hence river runoff change responds immediately to climate changes. It is important that both precipitation and evaporation are calculated by a GCM. Moreover, on large planes, such as the EEP, GCM data much better refl ect the state of climate compared to areas with complex mosaic surface conditions. Additionally, large amounts of paleoclimate data exist on the EEP for selected periods of the past.

Atmospheric circulation and storm events in the Baltic Sea

Abstract The storm events in the Baltic Sea are examined in connection with the main weather patterns grouped into the circulation types (CTs), and their changes in present climate. A calendar of storms was derived from results of wave model SWAN (Simulating WAves Nearshore) experiments for 1948-2011. Based on this calendar, a catalogue of atmospheric sea level pressure (SLP) fields was prepared for CTs from the NCEP/NCAR dataset. SLP fields were then analyzed using a pattern recognition algorithm which employed empirical orthogonal decomposition and cluster analysis. For every CT we conducted an analysis of their seasonal and interannual changes, along with their role in storm event formation. An increase of the storm CTs’ frequency in the second part of the 20th century was shown to be in a close agreement with teleconnection circulation patterns such as the Arctic Oscillation, North Atlantic Oscillation and the Scandinavian blocking.

Space-detailed climatic forecasting of air temperature and precipitation in Eastern Siberia on the basis of accounting for local features of the underlying surface

A physical-statistical approach is used for space specification of forecasting fields of air temperature and precipitation in the mid-21st century in Eastern Siberia. The initial data on the monthly mean values representing ensemble-averaged results of 12 general circulation models of the atmosphere and the ocean, with a 2° × 2° latitude-longitude grid are specified on a 12.5 × 12.5 km grid accounting for local features of surface topography and reflectivity. The most pronounced effect of increasing space resolution is found in the areas with complicated relief, especially in summer. This corresponds to physical properties of the processes affecting local features of precipitation and air temperature fields and demonstrates efficiency of the approach under use.

Mesoscale Atmospheric Modeling of Extreme Velocities over the Sea of Okhotsk and Sakhalin

A detailed modeling of meteorological parameters over the last 30 years (1985–2014) has been performed for the Sea of Okhotsk and Sakhalin regions in the frame of the COSMO-CLM regional mesometeorological nonhydrostatic atmospheric model. The downscaling technology is suggested and achieved with three consequent “nesting domains” (with 13.2-, 6.6-, and 2.2-km grid scales). The COSMO-CLM model reproduces (especially successfully on the 2.2-km grid scale) the extremes of wind velocity observed by meteorological stations well. Synoptic situations accompanied by extreme wind speeds are reproduced in detail.