Study of Johnsons Glacier (Livingston Island, Antarctica) by means of shallow ice cores and their tephra and by analysis of 137Cs content

With the aim of monitoring the dynamics of the Livingston Island ice cap, the Departament de Geodinàmica i Geofísica of the Universitat de Barcelona began yearly surveys in the austral summer of 1994-95 on Johnsons Glacier. During this field campaign 10 shallow ice cores were sampled with a manual ve rtical ice-core drilling machine. The objectives were: i) to detect the tephra layer accumulated on the glacier surface, attributed to the 1970 Deception Island pyroclastic eruption, today interstratified; ii) to verify wheter this layer might serve as a reference level; iii) to measure the 137Cs radio-isotope concentration accumulated in the 1965 snow stratum; iv) to use the isochrone layer as a mean of verifying the age of the 1970 tephra layer; and, v) to calculate both the equilibrium line of the glacier and average mass balance over the last 28 years (1965-1993). The stratigraphy of the cores, their cumulative density curves and the isothermal ice temperatures recorded confirm that Johnsons Glacier is a temperate glacier. Wind, solar radiation heating and liquid water are the main agents controlling the ve rtical and horizontal redistribution of the volcanic and cryoclastic particles that are sedimented and remain interstratified within the glacier. It is because of this redistribution that the 1970 tephra layer does not always serve as a very good reference level. The position of the equilibrium line altitude (ELA) in 1993, obtained by the 137Cs spectrometric analysis, varies from about 200 m a.s.l. to 250 m a.s.l. This indicates a rising trend in the equilibrium line altitude from the beginning of the 1970s to the present day. The varying slope orientation of Johnsons Glacier relative to the prevailing NE wind gives rise to large local differences in snow accumulation, which locally modifies the equilibrium line altitude. In the cores studied, 137Cs appears to be associated with the 1970 tephra layer. This indicates an intense ablation episode throughout the sampled area (at least up to 330 m a.s.l), which probably occurred synchronically to the 1970 tephra deposition or later. A rough estimate of the specific mass balance reveals a considerable accumulation gradient related to the increase with altitude

Prospección sísmica en el Glaciar Johnsons, Isla Livingston (Antártida). (campañas antárticas 1996-1997 y 1997-1998)

During two Antarctic summers (1996-97 and 1997-98), five seismic refraction (2.685 m long) and two reflection profiles (2.980 m long) were acquired on Johnsons Glacier (Livingston Island, Antarctica) in order to obtain information about the structure of the ice, characteristics of the ice-rock contact and the basement topography. Seismic refraction is an efficient method for calculating ice thickness and seismic waves velocity; whereas the seismic reflection is recommended because it leads us to a clear seismic image of bedrock topography and ice-bed contact. This study was completed using a raw data analysis (wavefront) which detected ice crevasses and delineated sectors with different glacier structures (accumulation and ablation zones). The information obtained from seismic data about the internal structure of the glacier constrains the glacial dynamics of Johnsons Glacier

The measurement of ice velocity, mass balance and thinning-rate on Johnsons Glacier, Livingston Island, South Shetland Islands, Antarctica

A network of twenty stakes was set up on Johnsons Glacier in order to determine its dynamics. During the austral summers from 1994-95 to 1997-98, we estimated surface velocities, mass balances and ice thickness variations. Horizontal velocity increased down-stream from 1 m a-1 near the ice divides to 40 m a-1 near the ice terminus. The accumulation zone showed low accumulation rates (maximum of 0,6 m a-1(ice)), whereas in the lower part of the glacier, ablation rates were 4,3 m a-1(ice). Over the 3-year study period, both in the accumulation and ablation zones, we detected a reduction in the ice surface level ranging from 2 to 10 m from the annual vertical velocities and ice-thinning data, the mass balance was obtained and compared with the mass balance field values, resulting in similar estimates. Flux values were calculated using cross-section data and horizontal velocities, and compared with the results obtained by means of mass balance and ice thinning data using the continuity equation. The two methods gave similar results

Floods and health in Gambella region, Ethiopia: a qualitative assessment of the strengths and weaknesses of coping mechanisms

BACKGROUND: Floods are the most frequent and devastating type of natural disaster worldwide, causing unprecedented deaths, diseases, and destruction of property and crops. Flooding has a greater impact in developing countries due to lack of sufficient disaster management structures and a lack of economic resources. OBJECTIVE: This study was conducted with the aim of contributing to the knowledge base of development strategies that reduce flood-related health risks in developing countries. The study focused particularly on assessing the flood risks and health-related issues in the Gambella region of Ethiopia; with the intent of producing relevant information to assist with the improvements in the efficacy of the current flood coping strategies in the region. METHODS: Data were gathered through interviews with 14 officers from different government and non-governmental organizations and a questionnaire survey given to 35 flood victims in Itang woreda. A qualitative approach was applied and the data were analyzed using content analysis. RESULTS: It was found that flooding is a common problem in Gambella region. The findings also indicate that the flood frequency and magnitude has increased rapidly during the last decade. The increase in floods was driven mainly by climate change and changes in land use, specifically deforestation. The reported main impacts of flooding on human health in Gambella region were deaths, injuries, and diseases such as malaria and diarrhea. Another notable consequence of flooding was crop destruction and subsequent malnutrition. CONCLUSIONS: Three weaknesses that were identified in the current coping strategies for flood-related health impacts in Gambella region were a lack of flood-specific policy, absence of risk assessment, and weak institutional capacity. This study recommends new policy approaches that will increase the effectiveness of the current flood coping strategies to sustainably address the impact of flooding on human health

Seismic detection and characterization of landslides and other mass movements

International audienceSeismic methods used in the study of snow avalanches may be employed to detect and characterize landslides and other mass movements, using standard spectrogram/sonogram analysis. For snow avalanches, the spectrogram for a station that is approached by a sliding mass exhibits a triangular time/frequency signature due to an increase over time in the higher-frequency constituents. Recognition of this characteristic footprint in a spectrogram suggests a useful metric for identifying other mass-movement events such as landslides. The 1 June 2005 slide at Laguna Beach, California is examined using data obtained from the Caltech/USGS Regional Seismic Network. This event exhibits the same general spectrogram features observed in studies of Alpine snow avalanches. We propose that these features are due to the systematic relative increase in high-frequency energy transmitted to a seismometer in the path of a mass slide owing to a reduction of distance from the source signal. This phenomenon is related to the path of the waves whose high frequencies are less attenuated as they traverse shorter source-receiver paths. Entrainment of material in the course of the slide may also contribute to the triangular time/frequency signature as a consequence of the increase in the energy involved in the process; in this case the contribution would be a source effect. By applying this commonly observed characteristic to routine monitoring algorithms, along with custom adjustments for local site effects, we seek to contribute to the improvement in automatic detection and monitoring methods of landslides and other mass movements

PERKOSAAN SEBAGAI ALASAN PENCABUTAN KEKUASAAN WALI DALAM PERKAWINAN

This research aims at describing the illigibility indicators of marital guardians based on Islamic marital law and common law perspective and its disenfranchisement due to rape and violence towards daughters. This research applies statute and comparative approach. The result reveals that there is a similarity between common law and Islamic marital law relating to religion and maturity backgrounds. Disenfranchisement can be implemented only for custody through court procedure. however, it is not related to guardian’s authority in marriage, to some extent islamic marital law gives chance to implement disenfranchisement due to rape and violence on those who are under guardians’ authority.   Penelitian ini bertujuan untuk mendeskripsikan tinjauan fiqh munakahat dan hukum positif terhadap indikator kelayakan seorang wali dalam perkawinan, dan pencabutan hak kewalian dalam pernikahan karena melakukan perkosaan dan kekerasan pada anak perempuannya. Penelitian ini menggunakan pendekatan perundang-undangan (statute approach) dan perbandingan (comparative approach). hasil penelitian menunjukkan adannya persamaan antara fiqh munakahat dan peraturan perundang-undangan dalam menentukan  kelayakan  wali  untuk  perkawinan  terkait  dengan  latar  belakang  agama dan aspek kedewasan. Pencabutan kekuasaan wali dalam konteks peraturan perundang- undangan hanya berkaitan dengan kuasa asuh orang tua melalui prosedur pengadilan dan tidak berlaku untuk kekuasaan wali dalam perkawinan, sedangkan fiqh munakahat memberikan peluang pencabutan kekuasaan wali dalam perkawinan jika wali melakukan kekerasan bahkan perkosaan terhadap orang yang berada di bawah perwaliannya

Die ganzheitliche Unternehmensanalyse auf Basis von Form 20-F- und Form 10-K-Jahresberichten

Die ganzheitliche Unternehmensanalyse auf Basis von Form 20-F- und Form 10-K-Jahresberichten. - Hamburg : Kovac, 2004. - XX, 295 S. - (Schriften zum betrieblichen Rechnungswesen und Controlling ; 23). - Zugl.: Augsburg, Univ., Diss., 200

Prospección sísmica en el Glaciar Johnsons, Isla Livingston (Antártida): (Campañas antárticas 1996-1997 y 1997-1998)

Durante las campañas antárticas de 1996-97 y 1997-98, se realizaron en el glaciar Johnsons (Isla Livingston, Antártida) cinco perfiles sísmicos de refracción (con un total de 2.685 m longitud) y dos perfiles de reflexión (2.980 m longitud) con el objetivo de obtener información sobre el grosor del hielo y la topografía del basamento. En cuanto a la sísmica de refracción, se presenta como un método eficaz para la obtención del espesor y de la velocidad del hielo, mientras que se propone la sísmica de reflexión como la técnica más adecuada para obtener información sobre la morfología de la cubeta glacial y el contacto hielo-roca. Los resultados aportados por los anteriores métodos se han completado con un análisis minucioso de los datos de campo (estudio del frente de ondas) obteniéndose la localización de sectores con fracturas (grietas) y pudiéndose distinguir áreas de distintas características glaciológicas (zonas de acumulación y ablación). Este conocimiento de la estructura interna del glaciar mediante prospección sísmica junto con otros datos glaciológicos permitirá modelizar la dinámica del flujo del glaciar Johnsons