High resolution climate simulations over the Arctic   总被引：1，自引：0，他引：1  

Annette Rinke  Klaus Dethloff  Arne Spekat  Wolfgang Enke  Jens Hesselbjerg Christensen 《Polar research》1999,18(2):143-150

The regional atmospheric climate model HIRHAM has been applied to the Arctic. Simulations for the whole year 1990 and for an ensemble of winter months (January of 1985-1995) have been performed. The comparison of the simulations with observational data analyses shows that the general spatial patterns are in good agreement with the data, in both the vertical structure and the annual cycle. For an additional validation of the model results, a multivariate classification of large-scale circulation patterns has been applied to the January ensemble model simulations.  相似文献   

Scaling Issues in Forest Succession Modelling   总被引：5，自引：0，他引：5  

Harald Bugmann  Marcus Lindner  Petra Lasch  Michael Flechsig  Beatrix Ebert  Wolfgang Cramer 《Climatic change》2000,44(3):265-289

This paper reviews scaling issues in forest succession modelling, focusing on forest gap models. Two modes of scaling are distinguished: (1) implicit scaling, i.e. taking scale-dependent features into account while developing model equations, and (2) explicit scaling, i.e. using procedures that typically involve numerical simulation to scale up the response of a local model in space and/or time. Special attention is paid to spatial upscaling methods, and downscaling is covered with respect to deriving scenarios of climatic change to drive gap models in impact assessments. When examining the equations used to represent ecological processes in forest gap models, it becomes evident that implicit scaling is relevant, but has not always been fully taken into consideration. A categorization from the literature is used to distinguish four methods for explicit upscaling of ecological models in space: (1) Lumping, (2) Direct extrapolation, (3) Extrapolation by expected value, and (4) Explicit integration. Examples from gap model studies are used to elaborate the potential and limitations of these methods, showing that upscaling to areas as large as 3000 km² is possible, given that there are no significant disturbances such as fires or insect outbreaks at the landscape scale. Regarding temporal upscaling, we find that it is important to consider migrational lags, i.e. limited availability of propagules, if one wants to assess the transient behaviour of forests in a changing climate, specifically with respect to carbon storage and the associated feedbacks to the atmospheric CO₂ content. Regarding downscaling, the ecological effects of different climate scenarios for the year 2100 were compared at a range of sites in central Europe. The derivation of the scenarios is based on (1) imposing GCM grid-cell average changes of temperature and precipitation on the local weather records; (2) a qualitative downscaling technique applied by the IPCC for central and southern Europe; and (3) statistical downscaling relating large-scale circulation patterns to local weather records. Widely different forest compositions may be obtained depending on the local climate scenario, suggesting that the downscaling issue is quite important for assessments of the ecological impacts of climatic change on forests.  相似文献   

Integrated Debris Flow Disaster Mitigation - A Comprehensive Method for Debris Flow Disaster Mitigation     

H. Wolfgang Weinmeister 《山地科学学报》2007,4(4):293-308

Integrated disaster mitigation needs interpreting torrent catchment areas as complex landscape systems. The history of valley-evolution shows the influence of climate and vegetation on the valley-evolution. The energy-concept (energy dissipation concept including the idea of the energy-line) is used for a simple explanation of debris flow. Examples of heavy debris flow disasters in controlled torrents in the Alps and Pyrenees give hints, which expanding the time scale can show that side-effects restrict or counteract the mitigation measures. A pallet of different mitigation measures to avoid or to reduce some of the side-effects is shown. The comprehensive method of disaster mitigation also includes the effect of vegetation. The pallet includes: avoiding hazards (hazard mapping, warning and alarming), appropriate land use and avoiding disaster-enhancing measures in the landscape and technical measures, which take into account their side-effects. The energy line is used as simple design theory. The Jiu-Jitsu Principle is explained too. With this comprehensive method a more sustainable reduction of disasters seems possible.  相似文献   

Can newly-forming stars act like Mini-QSOs?     

Wolfgang Kundt 《Astrophysics and Space Science》1984,98(2):275-280

The birth of stars takes place inside dense molecular clouds and is therefore difficult to observe with optical telescopes. Yet some stars form at the edges of clouds, and combined radio, infrared, optical and X-ray observations have recently revealed a great deal of structure: over a wide range of luminosities one observes high mass-outflow rates from pre-Main-Sequence and T Tauri-stars, with wind momenta exceeding the radiation momenta by large factors. The mass flows take the shape of two highly supersonic jets, perpendicular to a circumstellar disk. The jets have knotlike condensations, show strong linear polarization along the flow direction, and are often seen to reconverge. They resemble the twin-jets from the nuclei of active galaxies and may be driven by a similar type of engine. They may even hold a clue to the problem of how stars like our Sun got rid of the enormous angular momentum of their progenitor cloud. I propose that in both phenomena, the central engine is the maximally rotating core of a massive disk which produces a pair of thin, antipodal, magnetized relativistic jets.  相似文献   

Fireworks in Orion     

Wolfgang Kundt  Aylin Yar 《Astrophysics and Space Science》1997,254(1):1-12

The energetic outflow in Orion – which made headlines in the(northern-hemisphere) Summer of 1993 – is reinterpreted as a recent Supernova whose explosion went unnoticed, of age10^2.2±0.2 years. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

SS 433 — Again     

Wolfgang Kundt 《Astrophysics and Space Science》1987,134(2):407-414

The standard model for SS 433 encounters increasing difficulties, including geometrical and chemical irregularities, short-time correlations and the presence of circular polarization. It is argued that these difficulties disappear when one drops the assumption that the moving spectral lines are emitted by the (mapped) jets. All the spectral peculiarities can be blamed on (special) radiation from the inner accretion disk, at radius 10⁷ cm, around a young neutron star. The jets consist of relativistic pair plasma-like in all the other jet sources. A prediction is made for the center of the radio jets.  相似文献   

Geological investigations in West Nepal and their significance for the geology of the Himalayas     

Dr. Wolfgang Frank  Dr. Gerhard R. Fuchs 《International Journal of Earth Sciences》1970,59(2):552-580

In the sedimentary sequence of the Lower Himalayas monotonous geosynclinal deposits are overlain by various shallow-water deposits and a carbonate rock complex at the top. The age of this nonfossiliferous sequence is discussed. Transgressive Jurassic-Tertiary beds are evidence for a minimum thrust distance of 90 km of the Chail Nappes. The facies distribution points to the importance of an axis parallel to the Himalayan strike direction since Lower Paleozoic at least. The metamorphism of the overthrust units is described and the relation to the evolution of the orogen is discussed. An outline of the structure is given. The type of deformation and other features characteristic of the different tectonic units, as well as the relationship to the geology of the whole Himalayas are discussed. It is emphasized that structural development during the Himalayan orogenesis was largely determined by the earlier paleogeographic history. The picture of the structural development in successive stages is given.

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Zusammenfassung In der Sedimentfolge des Niederen Himalaya folgen über einförmigen Geosynklinalsedimenten wechselhafte Scichtwassersedimente mit einem abschließenden Karbonatgesteinskomplex. Das Alter dieser fossilleeren Schichtfolge ist noch nicht endgültig gesichert und wird diskutiert. Darüber liegen transgressiv Jura-Tertiär, deren Vorkommen bis 90 km unter die überschobenen Einheiten nach N reichen. Aus der Faziesanordnung ergibt sich eine Anlage der Himalaya-streichrichtung schon mindestens seit dem Altpaläozoikum. Die Metamorphose der überschobenen Decken wird beschrieben und die Möglichkeiten des Zusammenhanges mit der Orogenentwicklung diskutiert. Es werden die Grundzüge des tektonischen Baues, der charakteristische tektonische Stil der einzelnen Einheiten und deren Beziehungen zur Geologie des gesamten Himalayas beschrieben. Die Entwicklung während der Himalayaorogenese ist stark von der paläogeographischen Ausgangssituation bestimmt. Ein Bild der tektonischen Entwicklung in aufeinanderfolgenden Stadien wird gegeben.

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Résumé Dans la séquence sédimentaire du Bas Himalaya les sédiments géosynclinaux monotones sont couverts par des dépôts variables de faciès peu profond qui se terminent avec un ensemble de roches carbonatées. L'âge de cette séquence de couches non fossilifères n'est pas encore fixé et sera discuté. Audessus se trouvent des couches transgressives du Jurassique au Tertiaire qui s'étendent vers le N jusqu'à 90 km au-dessous des nappes chevauchantes. La position des faciès montre que la direction axiale du Himalaya existe au moins depuis le Paléozoique inférieur. Le metamorphisme des nappes charriées est décrit et les possibilités d'une connection avec l'évolution orogénique sont discutées. Les principaux traits de la structure et le style téctonique caractéristique des différentes unités ainsi que leur position dans l'ensemble géologique du Himalaya sont décrits. L'orogénèse du Himalaya est déterminée notamment par la situation paléogéographique. Enfin les différentes phases de l'évolution tectonique sont décrites.

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Neuere Ergebnisse der Anden-Stratigraphie von Süd-Mendoza (Argentinien) und benachbarter Gebiete und Bemerkungen zur Klimageschichte des südlichen Andenraums     

Dr. Wolfgang Volkheimer 《International Journal of Earth Sciences》1970,59(3):1088-1124

Zusammenfassung Es wird eine Übersicht über einige neuere Ergebnisse zur Stratigraphie der Anden von Süd-Mendoza und Neuquén und zur Paläoklimatologie der südlichen Anden gegeben.- 1. Zur Stratigraphie des prämesozoischen Grundgebirges am Südende der Frontalkordillere: Es handelt sich hier nicht, wie früher angenommen, um Präkambrium, sondern um einen wahrscheinlich devonischen Flysch, der von Tonaliten des tiefsten Karbons (334±16,5 MJ) intrudiert und von permotriassischen, meist sauren Vulkaniten überlagert wird. 2. Zur Stratigraphie des Lias und Unteren Dogger im Río-Atuel-Gebiet (Anden von Süd-Mendoza): Es wird ein stratigraphisches Gliederungsschema gegeben, nebst kurzem Abriß von Lithologie, Mächtigkeiten, Verbreitung, stratigraphischen Beziehungen, Fazies, Alter, Paläontologie, Entstehung und Korrelationen der behandelten Folgen. 3. In einem kurzen Überblick über die Stratigraphie des höheren Jura und der Kreide im Bereich der Mesozoischen Geosynklinale von Mendoza und Neuquén werden die neuesten Ergebnisse eingebaut. 4. Bemerkungen zur paläozoischen und mesozoischen Klimageschichte der südlichen Anden: Warmes Klima während des Altpaläozoikums, gemäßigtes bis kühlgemäßigtes Klima mit häufigen Gebirgsvergletscherungen im Karbon und wärmere Verhältnisse seit dem Perm und während des ganzen Mesozoikums charakterisieren, grob gesehen, den südlichen Andenraum. Die Klimazeugen spiegeln jedoch eine starke räumliche Differenzierung der Niederschläge wider. So ist z. B. das südliche Patagonien während langer Abschnitte des Mesozoikums durch pluviales Klima gekennzeichnet, während gleichzeitig in Mendoza und Neuquén zum Teil extrem aride Verhältnisse vorherrschten.

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New results on the stratigraphy of the Andean area of southern Mendoza and Neuquén and on the paleoclimatology of the southern Andes are reported.- 1. On the stratigraphy of the pre-Mesozoic basement of the southern end of the Frontal Cordillera: A probably Devonian flysch is described, which is intruded by a Lower Carboniferous tonalite (334±16,5 MY) and covered by Permotriassic, mainly acid vulcanites. 2. On the stratigraphy of the Lias and Lower Dogger in the Rio Atuel area (Andean southern Mendoza): A scheme of the stratigraphic subdivision and a short review of lithology, thicknesses, distribution, stratigraphic relations, facies, age, paleontology, origin and correlations of the formations treated are given. 3. A short review of new results on the stratigraphy of the Upper Jurassic and Cretaceous of the Mesozoic Geosyncline of Mendoza-Neuquén. 4. Annotations on the Paleozoic and Mesozoic climatic history of the southern Andes: Warm climate during the Lower Paleozoic, temperate to cool-temperate climate (with frequent mountain-glaciers) during the Carboniferous, and warm conditions since the Permian and during all the Mesozoic times, characterize, roughly, the southern Andean area. The climatic indicators reflect, however, strong differences of the quantity of precipitations in space. Thus southern Patagonia is characterized during long intervals of the Mesozoic by strongly pluvial conditions, while in Mendoza and Neuquén partly extreme arid conditions prevailed.

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Résumé De nouveaux résultats sur la stratigraphie des Andes, du sud de la province de Mendoza et de la province de Neuquén, et sur la paléoclimatologie des Andes méridionales sont présentés. 1. Stratigraphie du soubassement prémésozoïque de l'extrémité méridionale de la Cordillère Frontale: Les sédiments parfois légèrement métamorphiques de cette aire ne correspondent pas, comme on l'avait supposé antérieurement, au Précambrien; il s'agit d'un flysch probablement dévonien, pénétré par une tonalité du Carbonifère Inférieur (334±16,5 MA) et couvert en discordance par des volcanites surtout acides, d'âge permotriassique. - 2. Stratigraphie du Lias et du Dogger inférieur de la zone du fleuve Atuel (aire andine du sud de Mendoza): Un schéma de la subdivision stratigraphique est donné ainsi qu'une brève révision de la lithologie, des épaisseurs, de la distribution, des relations stratigraphiques, des faciès, de l'âge, de la paléontologie, de l'origine et des corrélations des formations traitées.- 3. Un bref résumé de la stratigraphie du Jurassique supérieur et du Crétacé du »Géosynclinal Mésozoïque« de Mendoza et Neuquén, en tenant compte des dernières résultats sur ce sujet. - 4. Notes sur l'histoire climatique palëozoïque et mesozoïque des Andes méridionales: climat chaud pendant le Paléozoïque inférieur, climat tempéré à tempéré froid avec de fréquentes glaciations de montagne pendant le Carbonifère et des conditions plus chaudes dès le Permien et pendant tout le Mésozoïque caractérisent grossièrement le domaine des Andes méridionales. Tout au long du Mésozoïque, cependant, les indicateurs climatiques reflètent une forte variation dans la quantité de précipitations dans l'espace et dans le temps. La Patagonie méridionale, par exemple, est caractérisée par des conditions fortement pluviales pendant des longues périodes du Mésozoïque, tandis que, simultanément, en Mendoza et Neuquén prédominèrent des conditions d'aridité jusqu'à extrème aridité.

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Resumen Se reseñan nuevos resultados acerca de la estratigrafía de los Andes del sur de Mendoza y Neuquén y sobre la paleoclimatología de los Andes australes. - 1. Acerca de la estratigrafía del basamento premesozoico de la terminación austral de la Cordillera Frontal: Las sedimentitas a veces levemente metamórficas de esta área no corresponden, como se había supuesto anteriormente, al Proterozoico; se trata de un flysch probablemente devónico, intruido por una tonalita del Carbónico Inferior (334±16,5 MA) y cubierto discordantemente por vulcanitas mayormente ácidas de edad permotriásica. 2. Sobre la estratigrafía del Lias y Dogger Inferior de la zona del Rio Atuel (àrea andina del sur de Mendoza): Se da un esquema de la subdivision estratigráfica y una breve reseña de la litología, espesores, distribución, relaciones estratigráficas, facies, edad, paleontología, origen y correlaciones de las formaciones tratadas. 3. Un breve resumen de la estratigrafía del Jurásico Superior y Cretácico del Geosinclinal Mesozoico de Mendoza y Neuquén, con consideración de los últimos avances. 4. Anotaciones acerca de la historia climática paleozoica y mesozoica de los Andes australes: Clima cálido durante el Paleozoico Inferior, clima templado a templado-frío con frecuentes glaciaciones de montaña durante el Carbónico y condiciones más cálidas desde el Pérmico y durante todo el Mesozoico caracterizan, groseramente, el espacio de los Andes australes. Sin embargo, los indicadores climáticos reflejan una fuerte diferenciación en cuanto a la cantidad de precipitaciones, en el espacio y el tiempo. La Patagonia austral, por ejemplo, se caracteriza durante largos tiempos del Mesozoico por condiciones fuertemente pluviales, mientras simultáneamente en Mendoza y Neuquén prevalecieron condiciones de aridez hasta extrema aridez.

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Mendoza Neuquén. 1) - : , ; , , , . 2) Rio Atuel, , , , , , , . 3) Mendoza Neuquén . 4) : ; — , — . — .

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Sedimentmikrobioiogie und ihre geologischen Aspekte     

Dr. Wolfgang E. Krumbein 《International Journal of Earth Sciences》1971,60(2):438-471

The influence of bacteria on recent sediments was first discussed in 1885, whenFischer andGazert were discussing the cycle of substances in the sea as well as in sediments. The influence of bacteria on the cycling of C, N, S, P in recent sediments and the open sea was soon accepted by marine geologists. Nevertheless, only very few experiments have, so far, shown more than qualitative and quantitative data collection in various restricted areas. This is due to the extensive and complicated chain of reactions on the surface of sediments and in the sediment itself. Biologists are asking for the amount of organic and inorganic matter which is reworked and released to the sea. Geologists usually emphasize the amount of substances which are sedimentated. For biologists the sediment is only part of their dominant ecosystem (the sea). While, for geologists the “sea” is only furnishing and influencing their first range system sediment. How much then, are bacteria involved in the slow process of conversion from a recent sediment to sedimentary rocks? Bacteria influence more or less strongly and to a more or less advanced degree of diagenesis:

1. The organic matter in sediments and the final form in which it is found.
2. The anions CO₃ ^2?, NO₃ ^?, OH-, SO₄ ^2?, PO₄ ^3? as well as their intermediate stages and the resulting minerals.
3. The cations H⁺, NH₄ ⁺, Ca²⁺, Fe²⁺, Fe³⁺, and a series of metals which are dissolved or precipitated by microbial activities as for example Fe, Mn, Cu, Ag, V, Co, Mo, Ni, U, Se, Zn.
4. The equilibrium of silicium. At least diatoms and radiolarians are precipitating silica, while other reactions which have been proved are not yet shown to influence marine sediments.
5. p_H-values and oxidation-reduction potentials of the sediment.
6. The composition of interstitial waters.
7. The surface activity of minerals, since bacteria are growing especially on particle surfaces.
8. The energy content and temperature of sediments.
9. The texture of fine grained sediments.
10. The fossilization of microfauna, macrofauna and trace fossils.

Sedimentology and mineralogy may also influence the bacterial activities and the composition of the microflora within sediments. Methods and problems of sediment microbiology are demonstrated by some investigations in the German Bay (North Sea) in connection with the first German Underwater Station (UWL). Ecological work proves to be difficult in various directions. The main cause of difficulties in microbiological work on sediments are the great variety of different factors influencing the environment (microbial, chemical, physical, mineralogical), the difficulty of taking representative samples, and the small amount of data which has been collected so far.  相似文献   

Die primär gerichteten Sedimentstrukturen,insbesondere die Schrägschichtung im Koblenzquarzit am Mittelrhein     

Wolfgang Niehoff 《International Journal of Earth Sciences》1958,47(1):252-321

Zusammenfassung Die Schrägschichtung des Koblenzquarzits, eines typischen devonischen Geosynklinalsedimentes, ist durch Wanderung von Großrippeln entstanden. Eine methodische Gefügeanalyse ergibt, daß die bisher für Schrägschichtungs-Untersuchungen angewandte rein statistische Behandlung der meßbaren Einzelrichtungen zu erheblichen Fehlern führen kann. Es wird eine neue Auswertungsmethode vorgelegt, die auf der Erfassung homogener Bereiche beruht. Für Schrägschichtungs-Messungen im gefalteten Gestein wird ein einfaches Reduktionsverfahren vorgeschlagen.Anschließend an die Beschreibung der übrigen Gefügearten von gerichteten Strömungsmerkmalen werden die Richtungen der subaquatischen Rutschungen zur Ermittelung der primären Böschungsrichtungen des Meeresbodens während der Sedimentation herangezogen.Im paläogeographischen Gesamtbild ergibt sich die Notwendigkeit zur Annahme devonischer Gezeitenströme, deren zeitlich und regional wechselnder Richtungsverlauf ebenso wie die Abbildung im Sediment durch die Gliederung des Sedimentationsraumes in Becken und Schwellen bestimmt wurde. Eine mit Hilfe der Sedimentationsrichtungen nachweisbare embryonale synsedimentäre Faltung steht mit der zyklischen Schichtgliederung wahrscheinlich in engem ursächlichem Zusammenhang.  相似文献