51 research outputs found
Slope estimation influences on ice thickness inversion models: A case study for Monte Tronador glaciers, North Patagonian Andes
Glacier ice thickness is crucial to quantifying water resources in mountain regions, and is an essential input for ice-flow models. Using a surface velocity inversion method, we combine ice thickness measurements with detailed surface elevation and velocity data, and derive ice thickness and volume estimates for the Monte Tronador glaciers, North Patagonian Andes. We test the dependence of the inversion model on surface slope by resampling glacier slopes using variable smoothing filter sizes of 16-720 m. While total glacier volumes do not differ considerably, ice thickness estimates show higher variability depending on filter size. Smaller (larger) smoothing scales give thinner (thicker) ice and higher (lower) noise in ice thickness distribution. A filter size of 300 m, equivalent to four times the mean ice thickness, produces a noise-free thickness distribution with an accuracy of 35 m. We estimate the volume of the Monte Tronador glaciers at 4.8 ± 2 kmwith a mean ice thickness of 75 m. Comparison of our results with earlier regional and global assessments shows that the quality of glacier inventories is a significant source of discrepancy. We show that including surface slope as an input parameter increases the accuracy of ice thickness distribution estimates.Fil: Zorzut, Valentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Ruiz, Lucas Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Rivera, Andres. Universidad de Chile; Chile. Universidad Austral de Chile; ChileFil: Pitte, Pedro Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Villalba, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Medrzycka, Dorotha. University of Ottawa; Canad
Conflict sources and management in ICU setting before and during COVID-19: a scoping review of the literature
Introduction. Conflicts are an inherent part of work within any organisation. They can arise between members of an interdisciplinary team (or between teams representing different departments), between patients and team members/family members, and patients' families and team members. Various conflict situations among employees may occur, therefore it is very important to identify their causes and take preventive or targeted corrective measures. The aim of this study was to review the available literature concerning conflicts arising in ICUs¿their types, methods of expression as well as their management and mitigation. In addition, we reviewed the available literature on the impact of the pandemic on the ICU environment caring for COVID-19 patients. Methods. The databases were searched. Single key words or their combinations using AND or OR operators were entered. Eventually, 15 articles were included in our review, which included two identical papers. Results. Conflicts occurred occasionally or rarely; researchers describing ethical conflicts demonstrated a moderate level of exposure to conflicts. The pandemic created many challenges and ethical dilemmas that are a source of ethical conflict. Conclusions. As conflict by nature remains inevitable, adequate procedures in conflict management should be developed and the leadership of managing personnel should be reinforced, because team members frequently expect guidance from their supervisors. The importance of training in interpersonal communication and crisis situation management in healthcare should therefore be emphasised
Rapid demise and committed loss of Bowman Glacier, northern Ellesmere Island, Arctic Canada
peer reviewedUsing historical and recent aerial photography and structure from motion (SfM) multiview stereo (MVS) techniques, we reconstruct the 1959 and 2018 ice surface topography and determine the geodetic mass balance of Bowman Glacier, a small mountain glacier on northern Ellesmere Island. This is combined with optical satellite imagery to reconstruct the evolution in extent of the glacier over six decades, and ground-penetrating radar measurements of ice thickness to estimate the remaining ice volume. Between 1959 and 2020, Bowman Glacier lost 78% of its extent (reducing from 2.75 to 0.61 km2), while average annual area loss rates have nearly tripled in the past two decades. Over the 1959–2018 period, glacier-wide ice-thickness change averaged −22.7 ± 4.7 m, corresponding to a mean specific annual mass balance of −347.0 ± 71.4 mm w.e. a−1. Projecting rates of area and volume change into the future indicates that the glacier will likely entirely disappear between 2030 and 2060. This study demonstrates the potential of SfM-MVS processing to generate elevation products from 1950/60s historical aerial photographs, and to extend observations of ice elevation and glacier volume change for the Canadian Arctic, prior to the satellite record
Dynamics and occurrence patterns of the Tatarian orache Atriplex tatarica L. (Chenopodiaceae) at the roadsides in Warsaw, Poland
Atriplex tatarica is an invasive annual plant from Central Asia. It is an early successional species of disturbed habitats, tolerant of a high content of NaCl. It grows also by the roadsides, on lawns by the streets and other places in cities sprayed with salt during snowfalls. The paper presents results of the analysis of abundance and patterns of occurrence of this invasive subhalophytic plant by the roadsides in the Warsaw city. We found that frequency and distribution of Atriplex tatarica increased significantly over the last few decades. The species grows chiefly along main streets which are de-iced. It forms monodominant patches of different length at the zone closest to the street verge. The NaCl concentration there is significantly higher than in the zones more distant from the street verge, although this parameter is very variable. The cover of other species increases with an increasing distance from the roadside verge
Effect of Disintegration Pretreatment of Sewage Sluoge for Enhanced Anaerobic Digestion
A sludge disintegration technology, presented in this paper, consists of pretreatment of the sludge before its anaerobic digestion. Disintegration of sludge has been recently incorporated into the wastewater treatment plant’s (WWTPs) process scheme in some countries to improve a hydrolysis phase of digestion. Better energy recovery is of crucial importance in the overall sludge disposal. This technology intensifies biogas production and improves the quality of digested sludge. The authors present results of their experiments, performed on sludge samples taken from the Gdansk WWTP, Poland. During experiments mixture of primary and waste activated sludge (WAS) taken from the aerobic bioreactor was used. The sludge was disintegrated mechanically in a laboratory scale by using a ultrasound generator Hielsher, Germany (the frequency was 24 kHz). The concentration of chemical oxygen demand (COD) was obtained according to standard methods and the degree of sludge disintegration (DD) in supernatant was calculated. The anaerobic digestion experiment was carried out in laboratory scale using two reactors (volume ca. 30 dm3 of each), with hydraulic retention time (HRT) of 15 days and under mesophilic conditions. The quantity and quality of produced biogas was measured. Results showed 20% increase of biogas and 10% increase of methane produced generated during anaerobic digestion process of disintegrated sludge compare to untreated one
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