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181.
This article summarises activities and preliminary results of the International Programme on Landslides Project no. 179 “Database of glacial lake outburst floods (GLOFs)”. This project is planned for 3 years (2013–2015); the main objectives of the first year are (1) to create an online database and (2) to select collaborating partners. A survey of existing and relevant documents, information and organisations has been initiated along with the creation of a website (www.glofs-database.org) and the establishment of international collaboration. The first preliminary results show regional differences in various attributes of GLOF events (e.g. triggers, chronological distribution). These differences should be taken into consideration in regionally focused methods of hazard assessment, mitigation and consequently risk management. 相似文献
182.
Cheval Sorin Bulai Ana Croitoru Adina-Eliza Dorondel Ștefan Micu Dana Mihăilă Dumitru Sfîcă Lucian Tișcovschi Adrian 《Theoretical and Applied Climatology》2022,149(1-2):253-272
Theoretical and Applied Climatology - In the last decades, anthropogenic drivers have significantly influenced the natural climate variability of Earth’s atmosphere. Climate change has become... 相似文献
183.
Current state of knowledge regarding the world’s wetlands and their future under global climate change: a synthesis 总被引:1,自引:0,他引:1
Wolfgang J. Junk Shuqing An C. M. Finlayson Brij Gopal Jan Květ Stephen A. Mitchell William J. Mitsch Richard D. Robarts 《Aquatic Sciences - Research Across Boundaries》2013,75(1):151-167
Wetlands cover at least 6 % of the Earth’s surface. They play a key role in hydrological and biogeochemical cycles, harbour a large part of the world’s biodiversity, and provide multiple services to humankind. However, pressure in the form of land reclamation, intense resource exploitation, changes in hydrology, and pollution threaten wetlands on all continents. Depending on the region, 30–90 % of the world’s wetlands have already been destroyed or strongly modified in many countries with no sign of abatement. Climate change scenarios predict additional stresses on wetlands, mainly because of changes in hydrology, temperature increases, and a rise in sea level. Yet, intact wetlands play a key role as buffers in the hydrological cycle and as sinks for organic carbon, counteracting the effects of the increase in atmospheric CO2. Eight chapters comprising this volume of Aquatic Sciences analyze the current ecological situation and the use of the wetlands in major regions of the world in the context of global climate change. This final chapter provides a synthesis of the findings and recommendations for the sustainable use and protection of these important ecosystems. 相似文献
184.
Xavier Tunc Isabelle Faille Thierry Gallou?t Marie Christine Cacas Pascal Havé 《Computational Geosciences》2012,16(2):277-296
In this paper, we are interested in modeling single-phase flow in a porous medium with known faults seen as interfaces. We
mainly focus on how to handle non-matching grids problems arising from rock displacement along the fault. We describe a model
that can be extended to multi-phase flow where faults are treated as interfaces. The model is validated in an academic framework
and is then extended to 3D non K-orthogonal grids, and a realistic case is presented. 相似文献
185.
J. Klime? M. D. Rowberry J. Blah?t M. Briestensky F. Hartvich B. Ko??ák J. Rybá? J. Stemberk P. ?těpan?íková 《Landslides》2012,9(3):407-415
It is possible to monitor slow-moving landslides and assess landslide stabilisation measures over protracted periods using an optical–mechanical crack gauge called a TM-71. This technical note outlines the theoretical background to the gauge and illustrates its practical application through a number of case studies. These studies are drawn from a range of landslide types and stabilisation measures. In terms of monitoring slow-moving landslides, three studies of deep-seated deformations are presented. The Taukliman coastal landslide on the Black Sea Coast is characterised by vertical and horizontal displacements of up to 0.2?mm?year?1 and sudden earthquake-induced dilations of up to 6?mm. The Parohy ridge spreading landslide in the Malá Fatra Mountains is characterised by gravitationally induced vertical displacements of 0.7?mm?year?1. The slope deformation that formed Cyrilka Cave in the Beskydy Mountains is characterised by very slow sinistral strike–slip movements of 0.8?mm?year?1. In terms of assessing landslide stabilisation measures, two studies are presented from Orava Castle in Slovakia and Tetín in the Czech Republic. The data recorded at these sites demonstrate that the constructed stabilisation measures have successfully alleviated the potential landslide hazard in both localities. These case studies clearly demonstrate that the gauge represents an important tool with which to monitor slow-moving landslides and assess landslide stabilisation measures. It is able to provide a precise three-dimensional record of deformation, withstand harsh environmental conditions, and record reliable data over protracted periods. 相似文献
186.
Mélanie Béguer Julien Bergé Caroline Gardia-Parège Laurent Beaulaton Gérard Castelnaud Michel Girardin Philippe Bo?t 《Estuaries and Coasts》2012,35(4):1082-1099
Spanning 20?years (1979?C2007), this study is the longest time series pertaining to the resident shrimp species Palaemon longirostris in a European estuary. Data from monthly faunal surveys undertaken across the middle part of the Gironde estuary from April 1979 along with data from a statistical analysis of the commercial catches throughout the entire estuary and river were considered in order to explore their inter and intra-annual variability and long-term trends. Long-term densities series as well as environmental series (salinity, discharge, temperature and NAO) were decomposed and the effects of environmental variables were also examined using statistical models (GAMs). This revealed important spatio-temporal variability and a significant overall decrease in abundance of this species in the Gironde estuary since the beginning of the 1980s. This long-term decrease in abundance corresponded significantly to long-term decreases in both discharge and the NAO index, as well a long-term increase in temperature and salinity in the middle part of the estuary. However, models showed that environmental factors explained only a small part of the variability. The upstream shift of the population highlighted in this study, probably due to the intrusion of marine waters into the middle section of the estuary, may also have contributed to its decrease in abundance. Inter-annual variability of densities was also significantly linked with inter-annual fecundity fluctuations, and a significant decrease in both mean female size and fecundity was shown for preserved samples from 1992. Moreover, the breeding period has been temporally stretched out and began earlier in more recent years, potentially due to the increase in spring temperature. 相似文献
187.
Benoît Laignel Florence Quesnel Robert Meyer Jean-Jacques Macaire 《Geodinamica Acta》2013,26(4):171-181
RésuméDepuis plus d’un siècle, l’origine autochtone ou allochtone des formations résiduelles à silex (en abrégé RS : résidus à silex) par rapport aux craies a fait l’objet de multiples discussions. Pour répondre à ce problème, un bilan d’altération entre ces deux formations a été effectué. Il repose sur une connaissance précise des âges des craies-mères des RS et sur des comparaisons granulométrique et chimique entre craie et RS. Ces comparaisons s’appuient sur les quantités de silex contenues dans les craies et les RS, sachant que les silex sont reconnus comme autochtones et que leur degré de dissolution est calculé. Les résultats apportent des informations sur l’évolution crétacée du Bassin anglo-parisien, avec la mise en évidence de la craie du Maastrichtien dans le bassin de Paris et la reconstitution des épaisseurs de craie dissoutes. De plus, ils indiquent que la stratigraphie des craies est conservée dans les profils de RS. Ils montrent également que les silex, éléments autochtones des RS, sont faiblement altérés. Les matrices des RS sont, quant à elles, en grande partie allochtones, notamment dans les dix mètres supérieurs de la formation. L’allochtonie diminue avec la profondeur, avec des RS pouvant être considérés comme des résidus d’altération de la craie au sens strict à partir de 20 mètres de profondeur. © Elsevier, Paris 相似文献
188.
Patterns of bivalve larvae dispersal in the deep Ahe atoll lagoon was studied by using a numerical 3D transport model (MARS3D) coupled with a vertical swimming sub-model, forced mainly by tide and wind-induced currents. The simulations were validated against observations of larval dispersal monitored several days throughout the lagoon. Connectivity matrices describing larval exchanges inside the lagoon were inferred. Larvae displayed a significant dispersal capacity at the lagoon scale, especially with dominant eastern winds. With southeastern winds, larvae mostly remained in their origin sector. The total export rate of the larvae, toward the ocean through the pass and shallow lagoon borders, was independent of the wind conditions, with 1% of the total concentration exported per day. However, the tide-driven currents efficiently flushed larvae in sectors close to the pass. Connectivity matrices suggest that the south and west sectors were more suitable for spat collecting and that central sectors would be efficient sanctuaries if genitors were accumulated. 相似文献
189.
Statistical characteristics of detectable inhomogeneities [IHs] in more than 600 observed meteorological time series have
been investigated using 16 objective homogenisation methods. Forty and 100 year long series of monthly or annual characteristics
of surface air temperature, precipitation total and relative air humidity from the Czech Republic and Hungary were examined.
The area of the part of the Czech observing network used here is smaller, and the density of sites is larger, than in the
Hungarian network, resulting in higher spatial correlations among data in the Czech dataset relative to the Hungarian dataset.
Time series with low number of gaps were supplied with interpolated data. Before homogenisation relative time series were
created, using weighted averages of time series from the same geographical region as reference series. For ease of comparison,
the magnitudes of the detected IHs are normalised with the standard deviation of the noise in the relative time series.
Results show that observed meteorological time series usually contain large number of small IHs, and that the magnitude distribution
of IHs from different data segments are surprisingly similar. Effects of different spatial coherences on the results are discussed. 相似文献
190.