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Rudolf?BráZdilEmail author Christian?Pfister Heinz?Wanner Hans?Von?Storch JüRg?Luterbacher 《Climatic change》2005,70(3):363-430
This paper discusses the state of European research in historical climatology. This field of science and an overview of its development are described in detail. Special attention is given to the documentary evidence used for data sources, including its drawbacks and advantages. Further, methods and significant results of historical-climatological research, mainly achieved since 1990, are presented. The main focus concentrates on data, methods, definitions of the “Medieval Warm Period” and the “Little Ice Age”, synoptic interpretation of past climates, climatic anomalies and natural disasters, and the vulnerability of economies and societies to climate as well as images and social representations of past weather and climate. The potential of historical climatology for climate modelling research is discussed briefly. Research perspectives in historical climatology are formulated with reference to data, methods, interdisciplinarity and impacts. 相似文献
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Karst spring responses examined by process-based modeling 总被引:8,自引:0,他引:8
Ground water in karst terrains is highly vulnerable to contamination due to the rapid transport of contaminants through the highly conductive conduit system. For contamination risk assessment purposes, information about hydraulic and geometric characteristics of the conduits and their hydraulic interaction with the fissured porous rock is an important prerequisite. The relationship between aquifer characteristics and short-term responses to recharge events of both spring discharge and physicochemical parameters of the discharged water was examined using a process-based flow and transport model. In the respective software, a pipe-network model, representing fast conduit flow, is coupled to MODFLOW, which simulates flow in the fissured porous rock. This hybrid flow model was extended to include modules simulating heat and reactive solute transport in conduits. The application of this modeling tool demonstrates that variations of physicochemical parameters, such as solute concentration and water temperature, depend to a large extent on the intensity and duration of recharge events and provide information about the structure and geometry of the conduit system as well as about the interaction between conduits and fissured porous rock. Moreover, the responses of solute concentration and temperature of spring discharge appear to reflect different processes, thus complementing each other in the aquifer characterization. 相似文献
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European floods during the winter 1783/1784: scenarios of an extreme event during the ‘Little Ice Age’ 总被引:1,自引:0,他引:1
Rudolf Brázdil Gaston R. Demarée Mathias Deutsch Emmanuel Garnier Andrea Kiss Jürg Luterbacher Neil Macdonald Christian Rohr Petr Dobrovolný Petr Kolář Kateřina Chromá 《Theoretical and Applied Climatology》2010,100(1-2):163-189
The Lakagígar eruption in Iceland during 1783 was followed by the severe winter of 1783/1784, which was characterised by low temperatures, frozen soils, ice-bound watercourses and high rates of snow accumulation across much of Europe. Sudden warming coupled with rainfall led to rapid snowmelt, resulting in a series of flooding phases across much of Europe. The first phase of flooding occurred in late December 1783–early January 1784 in England, France, the Low Countries and historical Hungary. The second phase at the turn of February–March 1784 was of greater extent, generated by the melting of an unusually large accumulation of snow and river ice, affecting catchments across France and Central Europe (where it is still considered as one of the most disastrous known floods), throughout the Danube catchment and in southeast Central Europe. The third and final phase of flooding occurred mainly in historical Hungary during late March and early April 1784. The different impacts and consequences of the above floods on both local and regional scales were reflected in the economic and societal responses, material damage and human losses. The winter of 1783/1784 can be considered as typical, if severe, for the Little Ice Age period across much of Europe. 相似文献
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Mark J. Nilges Yuanming Pan Rudolf I. Mashkovtsev 《Physics and Chemistry of Minerals》2009,36(2):61-73
The X- and W-band single-crystal electron paramagnetic resonance spectra of an electron-irradiated natural quartz permit quantitative
analysis of a 29Si hyperfine structure (A ~12.6 MHz) and an 27Al hyperfine structure (A ≤ 0.8 MHz) for a previously reported hole-like center. The 29Si hyperfine structure arises from interaction with two equivalent Si atoms and is characterized by the direction of the unique
A axis close to a Si–O bond direction. The 27Al hyperfine structure, confirmed by pulsed electron nuclear double resonance and electron spin echo envelope modulation spectra,
is characterized by the unique A axis approximately along a twofold symmetry axis. These 29Si and 27Al hyperfine data, together with published theoretical results on peroxy radicals in SiO2 as well as our own density functional theory (DFT) calculations on model peroxy centers, suggest this hole-like center to
have the unpaired spin on a pair of oxygen atoms linked to two symmetrically equivalent Si atoms and a substitutional Al3+ ion across the c-axis channel, a first peroxy radical in quartz. The nuclear quadrupole matrix P also suggests that the Al3+ ion corresponds closely to the diamagnetic precursor to the [AlO4]0 center.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献