34 research outputs found

    Distribution of cold and temperate ice and water in glaciers at Nordenskiöld Land, Svalbard, according to data on ground-based radio-echo sounding

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    The distribution of cold and temperate ice and water in polythermal glaciers is an important characteristic in studying their thermal regime, hydrology, and response to climate change. Data analysis of ground-based radio-echo sounding of 16 glaciers in Nordenskiöld Land in Spitsbergen shows that 4 of them are of cold type and 12 are of polythermal type. The mean thickness of cold and temperate ice in polythermal glaciers varies from 11±2 to 66±6 m and from 6±2 to 96±9 m, respectively, and their ratio varies from 0.30 to 5.31. The volume of temperate ice in polythermal glaciers varies from 0.0009 to 3.733 (±10%) km3. With water content of 2% in temperate ice in these glaciers they might contain in total up to ~93.5 × 106 m3 of liquid water. Radar data suggest the greater water content or greater size of water inclusions in near-bottom temperate ice

    Brief communication: Supraglacial debris-cover changesin the Caucasus mountains

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    Debris cover on glaciers can significantly alter melt, and hence, glacier mass balance and runoff. Debris coverage typically increases with shrinking glaciers. Here, we present data on debris cover and its changes for 559 glaciers located in different regions of the Greater Caucasus mountains based on 1986, 2000 and 2014 Landsat and SPOT images. Over this time period, the total glacier area decreased from 691.5km2 to 590.0km2 (0.52%yr-1. Thereby, the debris covered area increased from ~11 to ~24% on the northern, and from ~4 to 10% on the southern macro-slope between 1986 and 2014. Overall, we found 18% debris cover for the year 2014. With the glacier shrinkage, debris-covered area and the number of debris-covered glaciers increased as a function of elevation, slope, aspect, glacier morphological type, Little Ice Age moraines, and lithology

    Ice volume estimates from ground-penetrating radar surveys, western Nordenskiöld Land glaciers, Svalbard

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    As part of ongoing work within the SvalGlac project aimed to obtain a reliable estimate of the total ice volume of Svalbard glaciers and their potential contribution to sea level rise, in this contribution we present volume calculations, with detailed error estimates, for ten glaciers on western Nordenskiöld Land, central Spitsbergen, Svalbard. The volume estimates are based upon a dense net of GPR-retrieved ice thickness data collected over several field campaigns spanning the period 1999-2012, all of them except one within 2010-2012. The total area and volume of the ensemble are 113.38±0.09 km2 and 10.439±0.185 km3, respectively, while the individual areas, volumes and average ice thickness lie within 2.5-49.1 km2, 0.08-5.48 km3 and 29-108 m, respectively. The maximum recorded ice thickness, 265±15 m, corresponds to Fridtjovbreen, which has also the largest average thickness (108±1m). Available empirical formulae for Svalbard glaciers overestimate the total volume of these glaciers by 24% with respect to our calculation. On the basis of the pattern of scattering in the radargrams, we also analyse the hydrothermal structure of these glaciers. Nine out of ten are polythermal, while only one is entirely cold

    Supraglacial debris cover assessment in the Caucasus Mountains, 1986-2000-2014

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    The database contains glacier outlines from 1986-2000-2014. During the investigation Landsat (Landsat 5 TM, Landsat 7 ETM+, Landsat 8 OLI) and SPOT satellite imagery were analyzed to generate glacier outlines using manual and semi-automated methods

    The ice-free topography of Svalbard

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    We present a first version of the Svalbard ice-free topography (SVIFT1.0) using a mass-conserving approach for mapping glacier ice thickness. SVIFT1.0 is informed by more than 900’000 point-measurements of glacier thickness, totalling almost 8’300 km of thickness profiles. It is publicly available for download. Our estimate for the total ice volume is 6’253km3, equivalent to 1.6cm sea-level rise. The thickness map suggests that 13% of the glacierised area is grounded below sea-level. Thickness values are provided together with a map of error estimates that comprise uncertainties in the thickness surveys as well as in other input variables. Aggregated error estimates are used to define a likely ice-volume range of 5’200-7’400km3. The ice-front thickness of marine-terminating glaciers is a key quantity for ice-loss attribution because it controls the potential ice discharge by iceberg calving into the ocean. We find a mean ice-front thickness of 133m for the archipelago

    Relatório de estágio em farmácia comunitária

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    Relatório de estágio realizado no âmbito do Mestrado Integrado em Ciências Farmacêuticas, apresentado à Faculdade de Farmácia da Universidade de Coimbr

    Air and surface temperatures from mount Elbrus East summit area, Caucasus, 5620 m a.s.l., and surface and ground temperatures at fumarolic field, 2013-2015, thermistor measurements (iButton and Hobo)

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    The dataset represents temperature conditions of mount Elbrus East summit area. Two sites were organized: one at fumarolic field with sensors (iButton DL1922) on the surface at 0.05 cm depth and at 0.4 m depth, second at the rock nearby to represent natural conditions without volcanic influence with air (2 m height) and surface (0.05 m depth) sensors (Hobo U12-008 with TMC-HD sensors). Dataset covers July 2013 - July 2015, with some gaps due to air sensor damage. The MAST temperature out of fumarolic field is close to -16°C, and one at fumarolic field is close to 25°C
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