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201.
Rudolf Brázdil Petr Dobrovolný Jürg Luterbacher Anders Moberg Christian Pfister Dennis Wheeler Eduardo Zorita 《Climatic change》2010,101(1-2):7-40
Temperature reconstructions from Europe for the past 500 years based on documentary and instrumental data are analysed. First, the basic documentary data sources, including information about climate and weather-related extremes, are described. Then, the standard palaeoclimatological reconstruction method adopted here is discussed with a particular application to temperature reconstructions from documentary-based proxy data. The focus is on two new reconstructions; January–April mean temperatures for Stockholm (1502–2008), based on a combination of data for the sailing season in the Stockholm harbour and instrumental temperature measurements, and monthly Central European temperature (CEuT) series (1500–2007) based on documentary-derived temperature indices of the Czech Republic, Germany and Switzerland combined with instrumental records from the same countries. The two series, both of which are individually discussed in greater detail in subsequent papers in this special edition, are here compared and analysed using running correlations and wavelet analysis. While the Stockholm series shows a pronounced low-frequency component, the CEuT series indicates much weaker low-frequency variations. Both series are analysed with respect to three different long-period reconstructions of the North Atlantic Oscillation (NAO) and are compared with other European temperature reconstructions based on tree-rings, wine-harvest data and various climate multiproxies. Correlation coefficients between individual proxy-based series show weaker correlations compared to the instrumental data. There are also indications of temporally varying temperature cross-correlations between different areas of Europe. The two temperature reconstructions have also been compared to geographically corresponding temperature output from simulations with global and regional climate models for the past few centuries. The findings are twofold: on the one hand, the analysis reinforces the hypothesis that the index-data based CEuT reconstruction may not appropriately reflect the centennial scale variations. On the other hand, it is possible that climate models may underestimate regional decadal variability. By way of a conclusion, the results are discussed from a broader point of view and attention is drawn to some new challenges for future investigations in the historical climatology in Europe. 相似文献
202.
Rüdiger Glaser Dirk Riemann Johannes Schönbein Mariano Barriendos Rudolf Brázdil Chiara Bertolin Dario Camuffo Mathias Deutsch Petr Dobrovolný Aryan van Engelen Silvia Enzi Monika Halíčková Sebastian J. Koenig Oldřich Kotyza Danuta Limanówka Jarmila Macková Mirca Sghedoni Brice Martin Iso Himmelsbach 《Climatic change》2010,101(1-2):235-256
The paper presents a qualitative and quantitative analysis of flood variability and forcing of major European rivers since AD 1500. We compile and investigate flood reconstructions which are based on documentary evidence for twelve Central European rivers and for eight Mediterranean rivers. Flood variability and underlying climatological causes are reconstructed by using hermeneutic approaches including critical source analysis and by applying a semi-quantitative classification scheme. The paper describes the driving climatic causes, seasonality and variability of observed flood events within the different river catchments covering the European mainland. Historical flood data are presented and recent research in the field of historical flood reconstructions is highlighted. Additionally, the character of the different flood series is discussed. A comparison of the historical flood seasonality in relation to modern distribution is given and aspects of the spatial coherence are presented. The comparative analysis points to the fact that the number of flood events is predominately triggered by regional climatic forcing, with at most only minor influence on neighbouring catchments. The only exceptions are extreme, supra-regional climatic events and conditions such as anomalous cold winters, similar to that of 1784, which affected large parts of Europe and triggered flood events in several catchments as a result of ice-break at the beginning of the annual thaw. Four periods of increased occurrence of flooding, mostly affecting Central European Rivers, have been identified; 1540–1600, 1640–1700, 1730–1790, 1790–1840. The reconstruction, compilation and analysis of European-wide flood data over the last five centuries reveal the complexity of the underlying climatological causes and the high variability of flood events in temporal and spatial dimension. 相似文献
203.
204.
Temperature and precipitation fluctuations in the Czech Republic during the period of instrumental measurements 总被引:2,自引:0,他引:2
Rudolf Brázdil Pavel Zahradní?ek Petr Pi?oft Petr ?těpánek Monika Bělínová Petr Dobrovolny 《Theoretical and Applied Climatology》2012,110(1-2):17-34
The history of early meteorological observations using instruments in the Czech Lands is described (the longest temperature series for Prague-Klementinum starts in 1775, precipitation series for Brno in 1803). Using the PRODIGE method, long-term monthly temperature and precipitation series from selected secular stations were homogenised (for 10 and 12 stations, respectively). All the seasonal and annual temperature series for the common period 1882–2010 show a significant positive linear trend with accelerated warming from the 1970s onwards. No significant linear trends were disclosed in the series of seasonal and annual precipitation totals. Correlation coefficients between the Czech series analysed decrease as distances between measuring stations increase. A sharper decrease of correlations for precipitation totals displays much weaker spatial relationships than those for mean temperatures. The highest correlations between all stations appeared in 1921–1950, the lowest in 1891–1920 (temperature) and 1981–2010 (precipitation). Wavelet analysis reveals that very distinct annual cycles as well as the slightly weaker semi-annual ones are better expressed for temperature series than for precipitation. Statistically significant cycles longer than 1?year are temporally unstable and sporadic for precipitation, while in the temperature series cycles of 7.4–7.7 and 17.9–18.4?years were recorded as significant by all stations in 1882–2010 (quasi-biennial cycle of 2.1–2.2?years for half the stations). Czech homogenous temperature series correlate best with those of the Northern Hemisphere for annual, spring and summer values (with significant correlation coefficients between 0.60 and 0.70), but this relation is temporally unstable. Circulation indices, such as the North Atlantic Oscillation Index (NAOI) and the Central European Zonal Index (CEZI), may explain the greater part of Czech temperature variability, especially from December to March and for the winter; however, this relationship is much weaker, or even random, for precipitation series. Further, relationships with the Southern Oscillation Index (SOI) are weak and random. Relatively weak coincidences exist between statistically significant cycles in the Czech series and those detected in NAOI, CEZI and SOI series. 相似文献
205.
206.
Prof. Dr. Hans Rudolf von Gaertner 《International Journal of Earth Sciences》1967,56(1):691-696
Zusammenfassung Es wird die Darstellung der Fazies in einer Auswahl auf tektonischen Karten angeregt. Die Auswahl sollte nach der tektonischen Bedeutung der Fazies erfolgen. Labiler Schelf = faltbare Schichten, mächtige Kalkklötze sind solche lithotektonischen Komplexe. Molasse und Flysch, die bestimmte Entwicklungsstadien der Geosynklinale wiederspiegeln, gehören hierher. Besonders wichtig erscheint die Heraushebung der langanhaltenden Räume mit Schwellenfazies (Geantiklinalen) und der Kordilleren-Zonen.
Etwas abgeänderter Vortrag, gehalten Februar 1966 auf der Hauptversammlung der Geologischen Vereinigung in Wien. 相似文献
It is proposed to represent selectively the facies on tectonic maps. Selection should be governed by the tectonic significance of the facies. Such lithotectonic complexes are labile shelfs = foldable layers and thick limestones blocks. Also molasse and flysch reflecting certain stages of development of the geosyncline belong to this complex. The distinction of areas with long time swell facies (geoanticlines) and of Cordilleran zones, seems to be of particular importance.
Résumé L'auteur suggère de représenter en partie les faciès dans des cartes tectoniques. La sélection doit s'effectuer selon l'importance tectonique des faciès. Les plateformes continentales mobiles = couches pliables et de grands blocs calcaires constituent de tels complexes litho-tectoniques. De même en font partie la molasse et le flysch qui reflètent de certaines phases de développement des géosynclinaux. Il semble particulièrement important de mettre en valeur les régions à faciès de bombement (geanticlines) persistant et les zones de cordillères.
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Etwas abgeänderter Vortrag, gehalten Februar 1966 auf der Hauptversammlung der Geologischen Vereinigung in Wien. 相似文献
207.
James W Murray John G Dillard Rudolf Giovanoli Harald Moers Werner Stumm 《Geochimica et cosmochimica acta》1985,49(2):463-470
The initial solid phase oxidation products formed during the oxidation of aqueous Mn(II) at 25°C were studied as a function of time. The analyses included morphology (TEM), mineralogy (x-ray diffraction), ratio (iodometric method), oxidation state of manganese (XPS), and dissolved manganese. The initial solid formed under our conditions was Mn3O4 (hausmannite) which converted completely to γMnOOH (manganite) after eight months. βMnOOH (feitknechtite) appeared to be an intermediate in this transformation. The ratio was initially 1.37 and increased to 1.49 over the same time span. Throughout the course of this study the XPS analyses showed that the surface of the solids (<50 Å) was dominated by Mn(III). The solution pH and dissolved manganese concentrations were consistent with disproportionation and oxidation reactions that favor the transformation of Mn3O4 to γMnOOH but not to γMnO2. 相似文献
208.
Precambrian sedimentary carbonates: carbon and oxygen isotope geochemistry and implications for the terrestrial oxygen budget 总被引:2,自引:0,他引:2
Carbon isotope values of 260 Precambrian limestones and dolomites (most of them being substantially unaltered) have yielded an overall mean of vs. PDB; the corresponding oxygen values average at vs. SMOW. Like the overall mean, the δ 13C values furnished by individual carbonate occurrences are, as a rule, fairly “modern” and almost constant as from the very beginning of the sedimentary record. A remarkable exception are the “heavy” dolomites of the Middle Precambrian Lomagundi Group, Rhodesia, with vs. PDB. As a result of our measurements, the sporadic occurrence in the geological past of anomalously heavy carbonates seems to be established.The approximate constancy around zero per mill of the δ 13C values of marine carbonates through geologic time would imply a corresponding constancy of the relative proportion of organic carbon in the total sedimentary carbon reservoir since about 3.3 · 109 y ago (with Corg/Ctotal ? 0.2). Utilizing this ratio and current models for the accumulation of the sedimentary mass as a function of time, we get a reasonable approximation for the absolute quantity of organic carbon buried in sediments and, accordingly, of photosynthetic oxygen released. Within the constraints of our model (based on a terrestrial degassing constant λ = 1.16 · 10?9 y?1) close to 80% of the amount of oxygen contained in the present oxygen budget should have been released prior to 3 · 109 y ago. Since geological evidence indicates an O2-deficient environment during the Early and most parts of the Middle Precambrian, there is reason to believe that the distribution of this oxygen between the “bound” and the “molecular” reservoir was different from that of today (with effective O2-consuming reactions bringing about an instantaneous transfer to the crust of any molecular oxygen released). Accordingly, the amount of Corg in the ancient sedimentary reservoir as derived from our isotope data is just a measure of the gross amount of photosynthetic oxygen produced, withholding any information as to how this oxygen was partitioned between the principal geochemical reservoirs. As a whole, the carbon isotope data accrued provide evidence of an extremely early origin of life on Earth since the impact of organic carbon on the geochemical carbon cycle can be traced back to almost 3.5 · 109y. 相似文献
209.
Wolfgang Seifert Dieter Rhede Hans-Jürgen Förster Rudolf Naumann Rainer Thomas Jaromir Ulrych 《Mineralogy and Petrology》2014,108(5):645-662
Macrocrysts of corundum, ilmenite, and spinel-group minerals from alluvial deposits of the Eger Rift were studied for composition, texture, and mineral inclusions. All macrocrysts show usually magmatic corrosion textures indicating disequilibrium with the transporting alkali-basalt magma. Corundum grains, exclusively sapphires, were classified by trace-element signatures as magmatic and metamorphic types. Some sapphire grains show erratic compositions that may have resulted from a metasomatic overprint. The inclusion inventory of magmatic corundum suggests crystallization from a differentiated alkaline silicate melt. Corundum itself was never observed as an inclusion mineral. Magnesium- and Fe3+-rich ilmenite, described as typical mantle-derived species, is the dominant heavy mineral in almost all alluvial deposits of the Eger Rift. Most discrete macrocrysts are similar in appearance and composition to kimberlite- and basanite-related ilmenite. Ilmenite included in alluvial corundum and zircon grains differ from the bulk of discrete ilmenite grains by larger concentrations of Nb and Mn. The mantle origin of the Mg–Fe3+-rich ilmenite is confirmed by compositional and thermo-barometric comparison with ilmenite from clinoproxenitic and hornblenditic xenoliths, which probably originated in the Moho region. The Fe–Ti two-oxide geothermometry and oxygen-barometry of coexisting ilmenite–magnetite pairs yield equilibrium temperatures between 900 and 1,080 °C and oxygen fugacities log10fO2 between ?0.1 and 1.1 (relative to the NNO buffer), which indicate that the upper mantle as well as the mantle/crust transition zone below the rift is at least partially oxidized. The ilmenite macrocrysts were transported from the source region to the surface by explosive alkali-basalt magmas, as implied by the presence of basaltic-pipe breccias in close vicinity to some placer deposits. 相似文献
210.
Rudolf Schulze 《Theoretical and Applied Climatology》1961,11(2):211-223
Zusammenfassung Die optischen Eigenschaften des Polyäthylens werden erneut untersucht. Die Gründe der Kritik an der Strahlungsmessung unter Polyäthylen werden diskutiert, Verbesserungen der Polyäthylen-Instrumente werden vorgeschlagen.
Mit 7 Textabbildungen
Dem Gedenken an Dr.Franz Sauberer gewidmet. 相似文献
Summary The optical properties of polyethylene (polythene) are examined repeatedly. Thereupon the reasons for criticizing the methods of radiation measurement under polyethylene are discussed and improvements of polyethylene-instruments are suggested.
Résumé L'auteur étudie à nouveau les propriétés optiques du polyéthylène, examine les critiques faites aux mesures du rayonnement exécutées à l'aide de ce produit et propose des améliorations des instruments qui l'utilisent.
Mit 7 Textabbildungen
Dem Gedenken an Dr.Franz Sauberer gewidmet. 相似文献