Investigations on the Quaternary Glaciation in the Khumbu Himal (Nepal, East-Himalaya)

Based on geomorphological field work the mapping of former lateral/terminal moraines in the middle segment of the Bhotekoshi Nadi is quite similar to the geomorphological findings of Heuberger (1956: Fig. 2). The deductive calculation of the equilibrium line altitudes is oriented on the reconstructed types of former glaciers. Based on the geomorphological findings of this valley segment the relation of Neoglacial and Late Glacial ice margins of the glaciers of the tributary valleys of the Bhotekoshi Nadi is not conclusive. A post-late glacial maximum snow-line depression of at least 950 m has not obligatory caused an ice fill of the Bhotekoshi Nadi below 3200 m. This revised version was published online in July 2006 with corrections to the Cover Date.     

Polycyclic aromatic hydrocarbons in commercial fish and lobsters from the coastal waters of Madagascar following an oil spill in August 2009

Concentrations of polycyclic aromatic hydrocarbons were determined in species of commercial fish and lobsters following an oil-spill just off the protected Madagascan coastline. Samples were collected along the coastline within and outside the affected area. Summed PAH concentrations ranged from 1.9 μg kg⁻¹ to 63 μg kg⁻¹ wet weight, but with no higher molecular weight PAHs (>202 Da) being detected. All concentrations of benzo[a]pyrene, benz[a]anthracene and dibenz[a,h]anthracene were <0.1 μg kg⁻¹ wet weight, well within the EU and UK set limits for the protection of human health. Additionally, samples were calculated as the benzo[a]pyrene toxic equivalency quotient (TEQ) and found to be well below the level of concern in relation to health of human consumers. Evaluation of the biota PAH data indicated the origin of PAH was predominantly petrogenic with >80% arising from oil sources. Profile studies indicate a low-level multisource petrogenic contamination probably representing a pre-spill background for the area.     

Earthquake resistant construction techniques and materials on Byzantine monuments in Kiev

The study of the behaviour of historic buildings that have suffered from earthquakes has become a valuable tool for the understanding of earthquake resistant construction techniques and materials. Byzantine monuments of the 11–13th century in Kiev have been studied to provide insights into their effective dynamic properties facing severe earthquake history in the area. The recessed brickworks according to the “concealed course” construction technique of the St. Sophia Cathedral (11th century), the Church of St. Michael in the Vydubytskyi Monastery (11th century), the Tithe Church of the Assumption of the Virgin (10th century) and the Cathedral of Assumption of the Virgin (11th century) in the Monastery of the Caves (Pecherskyi monastery) in Kiev were studied and the material properties of bricks and lime mortars with ceramic fill were investigated (mechanical strength tests, mineralogical, chemical and microstructural analysis). The results show major similarities with those of the Byzantine monuments in Istanbul (Theodosian Walls and Hagia Sophia — 6–11th century construction phases), giving evidence of earthquake resistant construction techniques and materials allowing for continuous stresses and strains. Hence, didactics on proper restoration techniques and materials are deduced aiming at their present safety in the face of future earthquakes.     

Effects of bottom sediments on the survival of Enterobacter aerogenes in seawater

The survival of the coliform bacterium Enterobacter aerogenes in seawater was greatly affected by the underlying bottom sediments. The presence of sediments which contained higher concentrations of organic nutrients than the overlaying seawater prolonged the survival and even enabled growth of the bacterial cells. Results obtained from chemical analysis indicated that sediments of fine-grained, silt-clay type contained highest amounts of organic nutrients as compared with sediments with larger particle sizes such as silt and sand grains. Thus, nutrient contents of the sediments were found to be inversely proportional to sediment particle size. The degree of prolonged survival of E. aerogenes was also found to be inversely proportional to the size of the sediment particles presented. Release of the bound nutrients which became available to cells of E. aerogenes from sediments by action of waves and human activities can explain, at least in part, why high counts of coliform bacteria are obtained in coastal and beach waters.     

Couplage des équations de transfert de masse et des lois d''interactions solution-solide par l''utilisation des lanthanides comme traceurs — Approche expérimentale

In underground flow tracing studies, the estimation of the nature and the importance of interactions undergone by the substance used very often constitutes an obstacle to good modeling of mass-transfer processes in solution.

We propose a method to quantify these phenomena by the use of lanthanides as tracers.

For this study, we set up an analytical methodology adapted to routine measurements. The quality of five lanthanides as indicators has been examined. We have demonstrated the formation, by substitution, of a carbonate complex which is extremely stable in the natural environment. The field experiments carried out demonstrated the efficiency of those tracers and confirmed their great stability.

Tracer recovery graphs show that, in accord with our hypothesis, convection and dispersion are identical for all the lanthanide elements. Moreover, we have established a direct relation between their fixing rate on earth materials and the value of their stability constants.

Thus, we demonstrate the possibility of correlative multitracing, with known and quantifiable interelement relations.

Résumé

Dans les études de circulations souterraines par traceur, l'estimation de la nature et de l'importance des interactions subies par la substance utilisée constitue, bien souvent, un obstacle à une bonne modélisation des processus de transfert de masse en solution.

Nous proposons une méthode de quantification de ces phénomènes par l'utilisation des lanthanides comme traceurs.

Pour cette étude, nous avons mis au point une méthodologie analytique adaptée aux mesures de routine. Les qualités, en tant qu'indicateurs, de cinq lanthanides ont été examinées. Nous avons démontré la formation, par substitution, d'un complexe carbonaté extrèment stable en milieu naturel. Les expériences de terrain réalisées ont prouvé l'efficacité de ces traceurs et confirmé leur grande stabilité.

Les courbes de restitution obtenues ont montré que, conformément à nos hypothèses, la convection et la dispersion sont identiques pour l'ensemble de ces éléments. De plus, il a été établi une relation directe entre leurs taux de fixation sur le terrain et la valeur de leurs constantes de stabilité.

On dispose ainsi d'une possibilité de multitraçage corrélatif, avec des relations interélémentaires connues et quantifiables.     

Development of statistical seasonal prediction models of Arctic Sea Ice concentration using CERES absorbed solar radiation

Statistical seasonal prediction models for the Arctic sea ice concentration (SIC) were developed for the late summer (August-October) when the downward trend is dramatic. The absorbed solar radiation (ASR) at the top of the atmosphere in June has a significant seasonal leading role on the SIC. Based on the lagged ASR-SIC relationship, two simple statistical models were established: the Markovian stochastic and the linear regression models. Crossvalidated hindcasts of SIC from 1979 to 2014 by the two models were compared with each other and observation. The hindcasts showed general agreement between the models as they share a common predictor, ASR in June and the observed SIC was well reproduced, especially over the relatively thin-ice regions (of one- or multi-year sea ice). The robust predictability confirms the functional role of ASR in the prediction of SIC. In particular, the SIC prediction in October was quite promising probably due to the pronounced icealbedo feedback. The temporal correlation coefficients between the predicted SIC and the observed SIC were 0.79 and 0.82 by the Markovian and regression models, respectively. Small differences were observed between the two models; the regression model performed slightly better in August and September in terms of temporal correlation coefficients. Meanwhile, the prediction skills of the Markovian model in October were higher in the north of Chukchi, the East Siberian, and the Laptev Seas. A strong non-linear relationship between ASR in June and SIC in October in these areas would have increased the predictability of the Markovian model.     

A technique of radiosonde launch under the surface wind of high speed

Upper-air sounding is impacted by the surface wind of high speed in polar regions and in the areas affected by tropical cyclones. Considered are the main existing methods of radiosonde launching under such conditions. It is suggested to use the cone tower in order to provide a greater initial height of launching of the instrumental box as compared with the routine launching method. The employement of the tower allows using the wind force jointly with the lifting force of the balloon to deliver the instrumental box up to the top of the tower. Installation of the tower into the wind shelter secures the operator and provides the radiosonde launching even in the case of the very strong wind. The field model experiment corroborated the efficiency of the proposed scheme of radiosonde launching.     

Determination of ammonia emission rates from a tunnel ventilated chicken house using passive samplers and a Gaussian dispersion model

Atmospheric deposition can provide a significant fraction of the nitrogen loading to coastal waters. The Delmarva Peninsula, on the eastern shore of the Chesapeake Bay, is a region with intense poultry production that may supply a significant source of atmospheric ammonia (NH₃). There is a need to quantify ammonia NH₃ from representative growing methods in this region in order to more accurately estimate agricultural NH₃ emissions and to develop best management practices. In this study, NH₃ emissions were determined at an 18,600-bird tunnel-ventilated chicken house using a modified sampling grid (a planar arrangement normal to the length of the house) with Ogawa passive samplers to characterize the emission plume downwind from the house. This improvement in the sampling strategy, compared to a previous study, simplified the inverse Gaussian plume analysis which improved the confidence in the emission factors. In this study, a total of four separate plume characterizations were conducted over the final 3 weeks of the 6-week broiler grow-out cycle. The mean emission factor observed at the tunnel-ventilated house, 0.13 g NH₃–N/bird-day, was an order of magnitude lower than that previously observed at a nearby side-wall ventilated house. Although not all growing variables were measured, the large difference in emission factors between the two ventilation regimes suggest that modern, tunnel-ventilated houses may result in a significant decrease in NH₃ emissions compared with traditional growing methods. This variability in emission factors underscores the need for characterizing chicken houses under various conditions and determining the factors that control these atmospheric emissions.     

Recent trends in pre-monsoon daily temperature extremes over India

Extreme climate and weather events are increasingly being recognized as key aspects of climate change. Pre-monsoon season (March–May) is the hottest part of the year over almost the entire South Asian region, in which hot weather extremes including heat waves are recurring natural hazards having serious societal impacts, particularly on human health. In the present paper, recent trends in extreme temperature events for the pre-monsoon season have been studied using daily data on maximum and minimum temperatures over a well-distributed network of 121 stations for the period 1970–2005. For this purpose, time series of extreme temperature events have been constructed for India as a whole and seven homogeneous regions, viz., Western Himalaya (WH), Northwest (NW), Northeast (NE), North Central (NC), East coast (EC), West coast (WC) and Interior Peninsula (IP).