Concentration of organic compounds in the snow-ice cover of the Eastern Antarctic

This paper presents data on concentrations and composition of organic substances, lipids, and hydrocarbons, in the snow-ice cover of fast ices and continental lakes of Antarctic. It was shown that organic compounds were accumulated in layers with the most intense autochthonous processes (mainly at the snow-ice and ice-water boundaries). These zones remain active at a biogeochemical medium even at low temperatures. The maximum content of organic compounds (10-20 times that of the snow-ice cover of other regions) and a sharp change in the proportions of their migration forms in the ice volume were detected in the regions of penguin colonies (fast ice in the Buromsky Island and a lake in the Haswell Island). Contents and composition of hydrocarbons in Antarctic ices were compared with those of Arctic ices.

Album y universo lector femenino (Caracas, 1839)

El álbum fue un cuaderno de hojas en blanco de propiedad femenina. Por invitación de esas propietarias, escribían en sus páginas los más prestigiados escritores del período. Esa colaboración masculina, fue práctica decisiva en el siglo XIX que, en buena medida, contribuyó a la difusión del producto estético entre determinados círculos de lectores. A su vez, entre las damas venezolanas que tuvieron alguno de esos álbumes, estimuló la inclinación por la lectura literaria y, posteriormente, las indujo a producir escritos de similar naturaleza. Desde su entrada en la escena cultural venezolana, en 1839, derivaron otra serie de implicaciones a partir de su presencia, que también se examinan en estas páginas

Case studies of the effects of a total solar eclipse on weather with varying degrees of cloud cover using a local numerical weather prediction model

The importance of renewable energies for the European electricity market is growing rapidly. This presents transmission grids and the power market in general with new challenges which stem from the higher spatiotemporal variability of power generation. This uncertainty is due to the fact that renewable power production results from weather phenomena, thus making it difficult to plan and control. We present a sensitivity study of a total solar eclipse in central Europe in March. The weather in Germany and Europe was modeled using the German Weather Service's local area models COSMO-DE and COSMO-EU, respectively (http://www.cosmo-model.org/). The simulations were performed with and without considering a solar eclipse for the following 3 situations: 1. An idealized, clear-sky situation for the entire model area (Europe, COSMO-EU) 2. A real weather situation with mostly cloudy skies (Germany, COSMO-DE) 3. A real weather situation with mostly clear skies (Germany, COSMO-DE) The data should help to evaluate the effects of a total solar eclipse on the weather in the planetary boundary layer. The results show that a total solar eclipse has significant effects particularly on the main variables for renewable energy production, such as solar irradiation and temperature near the ground.

Album y universo lector femenino (Caracas, 1839)

El álbum fue un cuaderno de hojas en blanco de propiedad femenina. Por invitación de esas propietarias, escribían en sus páginas los más prestigiados escritores del período. Esa colaboración masculina, fue práctica decisiva en el siglo XIX que, en buena medida, contribuyó a la difusión del producto estético entre determinados círculos de lectores. A su vez, entre las damas venezolanas que tuvieron alguno de esos álbumes, estimuló la inclinación por la lectura literaria y, posteriormente, las indujo a producir escritos de similar naturaleza. Desde su entrada en la escena cultural venezolana, en 1839, derivaron otra serie de implicaciones a partir de su presencia, que también se examinan en estas páginas

Mapping decadal land cover changes in the woodlands of north eastern Namibia using the Landsat satellite archive (1975-2014)

Woodland savannahs provide essential ecosystem functions and services to communities. On the African continent, they are widely utilized and converted to intensive land uses. This study investigates the land cover changes of 108,038 km**2 in NE Namibia using multi-temporal, multi-sensor Landsat imagery, at decadal intervals from 1975 to 2014, with a post-classification change detection method and supervised Regression Tree classifiers. We discuss likely impacts of land tenure and reforms over the past four decades on changes in land use and land cover. These changes included losses, gains and exchanges between predominant land cover classes. Exchanges comprised logical conversions between woodland and agricultural classes, implying woodland clearing for arable farming, cropland abandonment and vegetation succession. The most dominant change was a reduction in the area of the woodland class due to the expansion of the agricultural class, specifically, small-scale cereal and pastoral production. Woodland area decreased from 90% of the study area in 1975 to 83% in 2014, while cleared land increased from 9% to 14%. We found that the main land cover changes are conversion from woodland to agricultural and urban land uses, driven by urban expansion and woodland clearing for subsistence-based agriculture and pastoralism.

Album y universo lector femenino (Caracas, 1839)

El álbum fue un cuaderno de hojas en blanco de propiedad femenina. Por invitación de esas propietarias, escribían en sus páginas los más prestigiados escritores del período. Esa colaboración masculina, fue práctica decisiva en el siglo XIX que, en buena medida, contribuyó a la difusión del producto estético entre determinados círculos de lectores. A su vez, entre las damas venezolanas que tuvieron alguno de esos álbumes, estimuló la inclinación por la lectura literaria y, posteriormente, las indujo a producir escritos de similar naturaleza. Desde su entrada en la escena cultural venezolana, en 1839, derivaron otra serie de implicaciones a partir de su presencia, que también se examinan en estas páginas

Concentration of organic compounds in slush, under-ice water, and the snow-ice fast-ice cover of the southeast sector of the Antarctic in April 2008

Data are presented on concentration of hydrocarbons (HC) relative to concentrations of suspended matter, lipids, organic carbon, and chlorophyll a in surface waters and snow-ice cover of the East Antarctic coastal areas. It was shown that growth of concentrations of aliphatic HC (AHC) to 30 µg/l in surface waters takes place in frontal zones and under young ice formation. AHC concentration in snow increases with growth of aerosol concentration in the atmosphere. In the lower part of ice, at the boundary with seawater, despite low temperatures, autochthonous processes may provide high AHC concentrations (up to 289 µg/l). Within the snow-ice cover on fast ice, concentration co-variations of all the compounds considered take place.