Brown Carbon and Black Carbon in the Smoky Atmosphere during Boreal Forest Fires

We have investigated the variability of smoke aerosol absorbing ability with variations in the content of brown carbon (BrC) and black carbon (BC). Using monitoring data on radiative characteristics of smoke aerosol at AERONET stations and the spatial distribution of aerosol optical depth (AOD) obtained by the MODIS spectrometer (Terra satellite), we have detected large-scale smokes during boreal forest fires in Russia and Canada (1995–2012). The spatial distribution (50°–70° N, 95°–125° W) and temporal variability (at AERONET station Fort McMurray) of AOD during the smoking of a part of Canada in July 2012 have been analyzed. AOD probability distributions for July 14–18, 2012, and an estimate of aerosol radiative forcing of smoke aerosol at the upper boundary of the atmosphere have been obtained. We have proposed a technique for the diagnostics of BrC and BC in smoke aerosol particles from the spectral dependence of the imaginary part of the refractive index. At a wavelength of 440 nm, the contributions of BrC and BC to the smokeaerosol absorbing abitity can be comparable in magnitude. In many cases, the absorption spectra of smoke aerosol can be adequately approximated by either power or exponential functions. The presence of BrC in smoke-aerosol particles highly extends the variety of observed absorption spectra in a smoky atmosphere and spectral dependences of single scattering albedo. In the spectral range of 440–1020 nm, the radiative characteristics of smoke aerosol are largely contributed by its fine mode.     

Problem of the formation of solid bitumens in the Tengiz deposit

Results of long-term petrological and geochemical investigations of solid bitumens (SB) in the Tengiz deposit are presented. It has been established that they belong to the class of epiimpsonites (Jacob, 1989), higher kerites (Radchenko and Uspenskii, 1979), or adulgites (mature bitumens) (Ammosov et al., 1987). Facies features of the accumulation of sediments, as well as tectonic and paleotemperature history of the Tengiz deposit are given. The upper carbonate sequence (3950–4500 m), which includes the main SB and oil reserves, accumulated on a shallow-water shelf that was favorable for the formation of collectors, whereas the lower sequence accumulated in a deep-water shelf belongs to oil source rocks in terms of facies features. Paleotectonic evolution of the Tengiz deposit includes three major stages: first subsidence, inversion, and repeated (second) subsidence. Each of these stages played an essential role in the genesis of SB formed from oil of an ancient deposit during the first subsidence. In the course of inversion, the ancient oil was transformed into maltha and asphalt (weakly altered bitumens) that were altered into epiimpsonites during the repeated subsidence. This process was accompanied by the release of light low-boiling hydrocarbons that made a significant contribution to the formation of the present-day oil pool in the Tengiz deposit.Translated from Litologiya i Poleznye Iskopaemye, No. 2, 2005, pp. 205–214.Original Russian Text Copyright © 2005 by Karpov, Stepanov, Tverdova, Sheikina.     

Distribution of artificial radionuclides in the Black Sea and Mediterranean Sea in 1989–1990

The result of research into the distribution of artificial radionuclides of¹³⁷Cs in the Black Sea and the Mediterranean Sea are reported. The data obtained permits consideration of the peculiarities of distribution of this radionuclide in the areas under investigation. The contribution of the Chernobyl radiocaesium to the total radioactivity of these water areas is estimated.Translated by Mikhail M. Trufanov.     

Large-Scale Haze over Eurasia in July 2016

Doklady Earth Sciences - This paper reports the estimated scales of optically dense haze over Eurasia for the period from July 15 to July 31, 2016, including the Siberian smoky haze (with a smoke...     

Understanding Convection in the Core-Collapse Supernovae Engine

Astronomy Reports - Understanding the nature of the standard engine behind core-collapse supernovae (SNe) has been an active area of research for over 60 yr pushing the limits of computational...     

The Saltating Particle Aleurite Mode in Wind–Sand Flux over a Desertified Area

Doklady Earth Sciences - The saltating particle aleurite mode has been discovered in the wind–sand flux over a desertified area. The approximation of the measured saltating particle...     

The time-dependent variation of hydrogeochemical characteristics, thermal regime, and biocenoses in the fresh and thermal waters of the Lake Karymskii basin following the catastrophic underwater eruption of 1996 in the Akademii Nauk Caldera, Kamchatka

The results of biohydrogeochemical monitoring are used to study time-dependent variations in the hydrogeochemical characteristics of the Lake Karymskii water mass, the state and characteristics of underwater discharge zones in the Tokarev crater (formed in 1996), hydrogeochemical characteristics of thermal springs around the lake, and the biota succession in the lake for the period 1996–2006 (2007). We detected a stratification in the chemical composition of water over depth and the presence of persistent zones of increased concentrations of dissolved oxygen. We found an alkalization of lake water and a decrease in its total salinity. The new thermal springs and underwater discharges of thermal water and gases were found to be continuing. The first data were obtained on the concentration of microelements in the thermal springs of the Karymskii basin. The biodiversity of algae in Lake Karymskii was largely increased by the species diversity of benthic Bacillariophyta. The plankton phytocomponent of the precatastrophic period was found to have been regenerated in the lake as of April 2007.     

Ionospheric Disturbances during Meteorological Storms

Geomagnetism and Aeronomy - Ionospheric disturbances during meteorological storms in the Kaliningrad region with a wind amplification of 8 points or higher on the Beaufort scale for the period...     

Ionospheric Disturbances due to the Influence of Localized Thermospheric Sources

Geomagnetism and Aeronomy - The paper presents the results of numerical modeling of the ionospheric disturbances from spatially localized, midlatitude, thermospheric sources that simulate the...     

Microparagenesis of diamonds and native aluminum in ejecta of recent volcanism

The particles of native aluminum that were extracted from ejecta of the 1988 Klyuchevskoi eruption were found to contain numerous inclusions of ultramicrodiamonds of the cuboctahedral habitus. We discuss the results of X-ray spectroscopy, X-ray structural, and spectroscopic studies of minerals that support the previous inference as to electric-shock–stimulated crystallization of diamonds from volcanic gases.