On the problem of determination of hummocky formation albedo

It is demonstrated within the frameworks of the analysis of determination methods of snowice cover reflectance that the problem of the measurement technique of hummocky formation albedo has not been studied enough. The results of in situ experiments carried out on the Arctic sea ice are presented. The results of ice hummock albedo measurements using different techniques are discussed. The need to organize the special experimental research for the development of practical recommendations for estimating the hummocky formation albedo is declared.     

Dynamics of solar activity and anomalous weather in summer 2010: 1. Sector boundaries: Anticyclone formation and destruction

A close synoptic relationship has been found, on the one hand, between the sector structure of the solar and interplanetary magnetic fields and, on the other hand, the structure of tropospheric parameters (the near-Earth pressure and temperature) in Central Russia during an anomalously hot anticyclonic weather in June–August 2010. It has been stated that the Earth crossed the magnetic sector boundaries in full agreement with the boundaries of meteorological parameters, structuring the formation, stabilization, and decay dynamics of anticyclones according to observations performed at IZMIRAN (Troitsk, φ = 55°, λ = 37°).     

Studying ionospheric responses to magnetic storms depending on the local time of the storm main phase onset

A morphological analysis of vertical sounding data obtained in Irkutsk from 2003 to 2008 has been performed. The AE index was used to determine the geomagnetic activity level, and the storm main phase onset was registered based on the D _st index. The ionospheric response to a magnetic storm was estimated based on the relative deviation of the critical frequency and altitude of the ionospheric F2 region from the median values. Superstrong magnetic storms and storms without positive initial phases were not considered when the data were selected. We found that positive ionospheric disturbances, which were accompanied by an increase in the F2 region maximum altitude, predominated between the storm initial phase and main phases during all considered magnetic storms. Between these storm phases, negative disturbances were only registered at night. Predominance of positive ionospheric disturbances over negative ones can be related to the selection of storms for studies.     

Jom-Bolok Holocene volcanic field in the East Sayan Mts., Siberia,Russia: structure,style of eruptions,magma compositions,and radiocarbon dating

Jom-Bolok volcanic field is located in the East Sayan Mts. of Siberia (Russia), a portion of the Asian convergent zone. It is located at the boundary of the Riphean Tuva-Mongolia massif, which was probably reactivated because of the interplay between far-field tectonic stress derived from the India–Asia collision zone and extension in the south-western Baikal rift system. The volcanic field comprises a number of hawaiitic lava flows, of various lengths, which flowed down paleorivers. Flows were fed by fissure eruptions and the largest lava flow field was dated as 7,130?±?140 cal ¹⁴C years BP using a buried organic sample found inside the associated cinder cone. This lava flow field is about 70 km long, ～100 km² in area, and 7.9 km³ in volume. The area and volume of this flow field ranks this eruption highly in the global record of fissure-fed effusive eruptions. This lava flow field makes up 97% of the entire Jom-Bolok volcanic field, a fact which raises a puzzling question: why and/or how did a relatively small-volume volcanic field produce such a large-volume individual eruption? A working hypothesis is that a pond of sublithospheric melt accumulated over a relatively prolonged period. This was then rapidly drained in response of tectonic changes triggered by unloading of ice in the Early Holocene.     

Renewal of deep waters of Lake Baikal revisited

The patterns of renewal of bottom waters in Lake Baikal under the influence of deep convection and intrusion of cold waters have been considered based on the data of temperature surveys of Lake Baikal conducted in 1993–2009. The volumes of the cold bottom layer with the maximums of 200–470 km³ in individual years and the values of its total cooling (−20–60 × 10⁹ MJ) have been determined for South, Middle, and North Baikal. The renewal process is asynchronous and proceeds with different activity in these parts of the lake, which indicates that the mechanisms that cause deep convection in the context of the great latitudinal length and differences in the climate and hydrological processes manifest themselves regionally. The volume of intrusions has been determined. Its average value for the period was higher in South Baikal (20 km³) than in Middle Baikal (9.8 km³) and North Baikal (8.6 km³). The volume of the intrusions in these parts of the lake was 30–70 km³ in some years.     

Isotopic markers of organic matter transformation at the water-sediment geochemical boundary

Doklady Earth Sciences -     

Extreme deviations of the sea level and the velocities of currents induced by constant winds in the Azov Sea

By the method of numerical modeling, we study the influence of the velocity of constant wind on the currents and oscillations of level in the Azov Sea. A three-dimensional nonlinear numerical model is applied to determine the regions characterized by the maximum and minimum values of the velocities of surface stationary currents and the highest deviations of level in the open part of the Azov Sea. In the presented maps, we indicate the points of the water area, where the extreme values of deviations of the sea level and the highest current velocities are attained. We analyze the influence of the velocity of constant wind on the time of attainment of the extreme values of elevations and lowerings of the sea level and current velocities.     

First record of a Vestimentifera (Polychaeta: Siboglinidae) from chemosynthetic habitats in the western Mediterranean Sea—Biogeographical implications and future exploration

A new population of vestimentiferan tubeworms was discovered during a recent expedition to a mud volcano field in the Alboran Sea, western Mediterranean Sea. Morphological data and mitochondrial cytochrome-c-oxidase subunit 1 (COI) sequences show that the Alboran tubeworm is essentially identical to Lamellibrachia sp. found in the eastern Mediterranean. This is the first record of a vestimentiferan species in the western basin of the Mediterranean, an area with direct connection to the Atlantic via the Strait of Gibraltar and therefore of great importance to the study of distributional patterns and evolution of Mediterranean species. We examine the current hypotheses on the biogeographic distribution of vestimentiferan species in the eastern Atlantic and Mediterranean Sea and conclude that independently of when Lamellibrachia colonized the Mediterranean, neither the present hydrological settings of both Mediterranean Sea and Atlantic Ocean, nor vestimentiferans reproductive biology are impeditive to the presence of the Mediterranean species of Lamellibrachia in the NE Atlantic. The West African and Lusitanian margins are the most likely places to find living populations of this species in the NE Atlantic.