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51.
Eleni E. Kalogirou Theodoros M. Tsapanos Vassilios G. Karakostas Vassilios P. Marinos Alexandros Chatzipetros 《Acta Geophysica》2014,62(6):1387-1412
In the beginning of July 2010, a ground fissure was observed in the field near the village of Mavropigi (Northern Greece) and specifically in its NW side. Later on (early September), a second ground fissure was perceived, close and almost parallel to the first one and very close to the limits of the lignite exploitation mine (by the Public Power Corporation, PPC). It was observed that the village of Mavropigi slides away slowly towards the PPC lignite mine. Geological, seismological, as well as geotechnical survey in the field indicated that the phenomenon is related to the coal mining exploitation in the near vicinity of the village rather than to any seismotectonic activity in the surrounding area. 相似文献
52.
Eleni Daskalaki Gerassimos A. Papadopoulos Konstantinos Spiliotis Constantinos Siettos 《Journal of Seismology》2014,18(1):37-46
Based on the theory of complex networks, we quantify for the first time correlations between seismic events occurring in the Hellenic arc and Trench system, which is the most seismogenic structure in the European–Mediterranean region. We examine how relatively strong events with their aftershock sequences trigger phase transitions of the underlying network topology of seismic activity from random to scale-free structures. In particular, we show that the network is characterized by a highly clustered spatial structure giving rise to heterogeneous networks exhibiting enhanced small-world attributes. 相似文献
53.
The simulation of European heat waves from an ensemble of regional climate models within the EURO-CORDEX project 总被引:4,自引:1,他引:3
Robert Vautard Andreas Gobiet Daniela Jacob Michal Belda Augustin Colette Michel Déqué Jesús Fernández Markel García-Díez Klaus Goergen Ivan Güttler Tomáš Halenka Theodore Karacostas Eleni Katragkou Klaus Keuler Sven Kotlarski Stephanie Mayer Erik van Meijgaard Grigory Nikulin Mirta Patarčić John Scinocca Stefan Sobolowski Martin Suklitsch Claas Teichmann Kirsten Warrach-Sagi Volker Wulfmeyer Pascal Yiou 《Climate Dynamics》2013,41(9-10):2555-2575
The ability of a large ensemble of regional climate models to accurately simulate heat waves at the regional scale of Europe was evaluated. Within the EURO-CORDEX project, several state-of-the art models, including non-hydrostatic meso-scale models, were run for an extended time period (20 years) at high resolution (12 km), over a large domain allowing for the first time the simultaneous representation of atmospheric phenomena over a large range of spatial scales. Eight models were run in this configuration, and thirteen models were run at a classical resolution of 50 km. The models were driven with the same boundary conditions, the ERA-Interim re-analysis, and except for one simulation, no observations were assimilated in the inner domain. Results, which are compared with daily temperature and precipitation observations (ECA&D and E-OBS data sets) show that, even forced by the same re-analysis, the ensemble exhibits a large spread. A preliminary analysis of the sources of spread, using in particular simulations of the same model with different parameterizations, shows that the simulation of hot temperature is primarily sensitive to the convection and the microphysics schemes, which affect incoming energy and the Bowen ratio. Further, most models exhibit an overestimation of summertime temperature extremes in Mediterranean regions and an underestimation over Scandinavia. Even after bias removal, the simulated heat wave events were found to be too persistent, but a higher resolution reduced this deficiency. The amplitude of events as well as the variability beyond the 90th percentile threshold were found to be too strong in almost all simulations and increasing resolution did not generally improve this deficiency. Resolution increase was also shown to induce large-scale 90th percentile warming or cooling for some models, with beneficial or detrimental effects on the overall biases. Even though full causality cannot be established on the basis of this evaluation work, the drivers of such regional differences were shown to be linked to changes in precipitation due to resolution changes, affecting the energy partitioning. Finally, the inter-annual sequence of hot summers over central/southern Europe was found to be fairly well simulated in most experiments despite an overestimation of the number of hot days and of the variability. The accurate simulation of inter-annual variability for a few models is independent of the model bias. This indicates that internal variability of high summer temperatures should not play a major role in controlling inter-annual variability. Despite some improvements, especially along coastlines, the analyses conducted here did not allow us to generally conclude that a higher resolution is clearly beneficial for a correct representation of heat waves by regional climate models. Even though local-scale feedbacks should be better represented at high resolution, combinations of parameterizations have to be improved or adapted accordingly. 相似文献