Zusammenhälige zwischen einer seltenen Haloerscheiuung und der Gestalt der Eiskristalle     

Hermann Steinmetz  Helmut Weickmann 《Contributions to Mineralogy and Petrology》1947,1(1):31-36

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Meridional transport of particles and standard vector deviation of upper winds     

Hermann Flohn 《Pure and Applied Geophysics》1961,50(1):229-234

Summary The meridional dispersion of particles depends from the mean meridional circulation (Hadley-type) and the turbulent mass exchange. The velocity of the latter process can be estimated with the standard deviation of the meridional wind component, which is represented in two diagrams.

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Zusammenfassung Die meridionale Ausbreitung von Partikeln hängt von der mittleren Meridionalzirkulation in der Vertikalebene (Hadley-Zirkulation) und dem turbulenten Massenaustausch ab. Die Geschwindigkeit des turbulenten Austauschs kann mit Hilfe der Streung der meridionalen Windkomponente abgeschätzt werden. Diese Größe wird in zwei Diagrammen dargestellt.

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Reduktionsszenarien für Flusseinträge in ihrer Wirkung auf die Eutrophierung der Nordsee,simuliert mit dem Ökosystemmodell ERSEM (Zusammenfassung)     

Lenhart  Hermann 《Ocean Dynamics》1999,51(10):165-165

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Quantitative accuracy analysis of the discontinuous Galerkin method for seismic wave propagation   总被引：1，自引：0，他引：1  

Martin Käser  Verena Hermann  Josep de la Puente 《Geophysical Journal International》2008,173(3):990-999

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Holocene environmental dynamics of south-eastern Brazil recorded in laminated sediments of Lago Aleixo     

Dirk Enters  Hermann Behling  Christoph Mayr  Lydie Dupont  Bernd Zolitschka 《Journal of Paleolimnology》2010,44(1):265-277

Environmental changes of the last 9,300 years were reconstructed by geochemical and pollen analyses of a 14-m-long, laminated sediment core from Lago Aleixo, south-eastern Brazil. Fossil pollen assemblages indicate open savannah vegetation (campo cerrado) and gallery forests until approximately 6,900 cal. BP. During that time, siderite laminae were deposited under anoxic conditions at the lake bottom. Then, increased rainfall and a shorter annual dry period allowed gallery forests and semi-deciduous forests to expand, leading to more closed cerrado vegetation. High-intensity rainfall events during this period are recorded as peaks in K and Ti concentrations. The sediment facies during this period consists of alternating layers of diatoms and minerogenic matter. C/N ratios imply that algae and perhaps soils, too, were the main contributors to sediment organic matter. Biogenic silica and δ¹³C_org variations indicate increasing primary productivity, which was related to higher nutrient flux from intensified leaching of soils, as shown by rising K/Al ratios. Around 800 cal. BP, a closed, semi-deciduous forest developed under present-day climate conditions. Slope stabilization diminished erosion processes in the catchment and caused reduced input of minerogenic matter into the basin. Human impact is evident in the topmost homogeneous sediments, as removal of the stabilizing forest cover amplified soil erosion. The continuous trend to more humid conditions during the Holocene probably reflects increased influence of the Amazon Basin as a moisture source. We conclude that the Lago Aleixo sediment archive was a sensitive recorder of environmental dynamics in tropical South America, which were mainly controlled by changes in precipitation patterns.  相似文献   

Neutral density depletions associated with equatorial plasma bubbles as observed by the CHAMP satellite     

Jaeheung Park  Hermann Lühr  Kyoung Wook Min 《Journal of Atmospheric and Solar》2010,72(2-3):157-163

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The 11 March 2011 Tohoku Tsunami Survey in Rikuzentakata and Comparison with Historical Events     

Haijiang Liu  Takenori Shimozono  Tomohiro Takagawa  Akio Okayasu  Hermann M. Fritz  Shinji Sato  Yoshimitsu Tajima 《Pure and Applied Geophysics》2013,170(6-8):1033-1046

On 11 March 2011, a moment magnitude M _w = 9.0 earthquake occurred off the Japan Tohoku coast causing catastrophic damage and loss of human lives. In the immediate aftermath of the earthquake, we conducted the reconnaissance survey in the city of Rikuzentakata, Japan. In comparison with three previous historical tsunamis impacting the same region, the 2011 event presented the largest values with respect to the tsunami height, the inundation area and the inundation distance. A representative tsunami height of 15 m was recorded in Rikuzentakata, with increased heights of 20 m around rocky headlands. In terms of the inundation area, the 2011 Tohoku tsunami exceeded by almost 2.6 times the area flooded by the 1960 Chilean tsunami, which ranks second among the four events compared. The maximum tsunami inundation distance was 8.1 km along the Kesen River, exceeding the 1933 Showa and 1960 Chilean tsunami inundations by factors of 6.2 and 2.7, respectively. The overland tsunami inundation distance was less than 2 km. The tsunami inundation height linearly decreased along the Kesen River at a rate of approximately 1 m/km. Nevertheless, the measured inland tsunami heights exhibit significant variations on local and regional scales. A designated “tsunami control forest” planted with a cross-shore width of about 200 m along a 2 km stretch of Rikuzentakata coastline was completely overrun and failed to protect the local community during this extreme event. Similarly, many designated tsunami shelters were too low and were overwashed by tsunami waves, thereby failing to provide shelter for evacuees—a risk that had been underestimated.  相似文献   

Erratum to: The Geodesist’s Handbook 2012     

Hermann Drewes 《Journal of Geodesy》2013,87(2):195-197

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Environmental changes in southeastern Amazonia during the last 25,000 yr revealed from a paleoecological record     

Barbara Hermanowski  Marcondes Lima da Costa  Hermann Behling 《Quaternary Research》2012,77(1):138-148

New pollen, micro-charcoal, sediment and mineral analyses of a radiocarbon-dated sediment core from the Serra Sul dos Carajás (southeast Amazonia) indicate changes between drier and wetter climatic conditions during the past 25,000 yr, reflected by fire events, expansion of savanna vegetation and no-analog Amazonian forest communities. A cool and dry last glacial maximum (LGM) and late glacial were followed by a wet phase in the early Holocene lasting for ca. 1200 yr, when tropical forest occurred under stable humid conditions. Subsequently, an increasingly warm, seasonal climate established. The onset of seasonality falls within the early Holocene warm period, with possibly longer dry seasons from 10,200 to 3400 cal yr BP, and an explicitly drier phase from 9000 to 3700 cal yr BP. Modern conditions with shorter dry seasons became established after 3400 cal yr BP. Taken together with paleoenvironmental evidence from elsewhere in the Amazon Basin, the observed changes in late Pleistocene and Holocene vegetation in the Serra Sul dos Carajás likely reflect large-scale shifts in precipitation patterns driven by the latitudinal displacement of the Inter-Tropical Convergence Zone and changes in sea-surface temperatures in the tropical Atlantic.  相似文献   

Upper Pleistocene to Holocene peatland evolution in Southern Brazilian highlands as depicted by radar stratigraphy,sedimentology and palynology     

Marcelo Accioly Teixeira de Oliveira  Jorge Luis Porsani  Gisele Leite de Lima  Vivian Jeske-Pieruschka  Hermann Behling 《Quaternary Research》2012,77(3):397-407

Paleoenvironmental interpretation of proxy data derived from peatlands is largely based upon an evolutionary model for ombrotrophic bogs, in which peat accumulates in still environments. Reports on proxies obtained from minerotrophic fens, where hydrologic inputs are variable, are less common. In this study, a highland peatland in southern Brazil is presented through ground penetrating radar (GPR) and sedimentological, palynological and geochronologic data. The radar stratigraphic interpretation suggests a relatively complex history of erosion and deposition at the site since the beginning of Marine Isotope Stage 3 (MIS 3) interstadial period. In spite of this, radar stratigraphic and palynologic interpretations converge. Electromagnetic reflections tend to group in clusters that show lateral coherence and correlate with different sediment types, while pollen grains abound and are well preserved. As a result, the study of minerotrophic fens provides a source of proxies, suggesting that ombrotrophic bogs are not the only reliable source of data in wetlands for palynological analysis.  相似文献