18.6-year lunar nodal tides from altimeter data     

Josef Y. Cherniawsky  Michael G.G. Foreman  Sok Kuh Kang  Remko Scharroo  A. Jane Eert 《Continental Shelf Research》2010

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Tides in marginal seasA special issue in memory of Professor Alexei V. Nekrasov     

Alexander B. Rabinovich  Michael G.G. Foreman  Boris A. Kagan  Josef Y. Cherniawsky 《Continental Shelf Research》2010

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Association Between Extraterrestrial Phenomena And Weather Changes In The Northern Hemisphere In Winter     

Josef Bochníček  Pavel Hejda 《Surveys in Geophysics》2002,23(4):303-333

This paper includes a discussion of the validity of theobjections which are usuallyraised against the physical plausibility of the correlationsbetween extraterrestrialphenomena and changes in circulation in the lower atmosphere.The behaviour of the winterlower troposphere in the Northern Hemisphere was analysed bothon a month-to-month timescale and on a day-to-day time scale. The mechanisms which cansatisfactorily explainthe behaviour of the winter lower troposphere on these timescales have been described.The basic features of the results presented were explained bymeans of a mechanism basedon the propagation of planetary waves. Attention was focussedon studying the connectionsamong the changes in the pressure and temperature fields, thechanges in solar/geomagnetic activity and QBO phases by the method of composites. It hasbeen found that the compositeswithout considering QBO phases are similar to the QBO-eastpatterns under the highestactivities. Pressure deviations during QBO-west high solaractivity or low geomagneticactivity and temperature deviations during QBO-east/west lowgeomagnetic activity provedto be of negligible statistical significance.  相似文献   

Shape Determination of the Asteroid (6053) 1993 BW₃     

Josef ?urech 《Icarus》2002,159(1):192-196

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Beiträge zur Typisierung von Falten     

Josef Ladurner 《Mineralogy and Petrology》1954,4(1-4):34-43

Ohne ZusammenfassungMit 2 Textabbildungen und 11 Gefügediagrammen.  相似文献   

Abrupt deglaciation on the northeastern Tibetan Plateau: evidence from Lake Qinghai   总被引：4，自引：0，他引：4  

Xiuju Liu  Steven M. Colman  Erik T. Brown  Andrew C. G. Henderson  Josef P. Werne  Jonathan A. Holmes 《Journal of Paleolimnology》2014,51(2):223-240

We inferred the climate history for Central Asia over the past 20,000 years, using sediments from core QH07, taken in the southeastern basin of Lake Qinghai, which lies at the northeastern margin of the Tibetan Plateau. Results from multiple environmental indicators are internally consistent and yield a clear late Pleistocene and Holocene climate record. Carbonate content and total organic carbon (TOC) in Lake Qinghai sediments are interpreted as indicators of the strength of the Asian summer monsoon. Warm and wet intervals, associated with increased monsoon strength, are indicated by increased carbonate and TOC content. During the glacial period (~20,000 to ~14,600 cal year BP), summer monsoon intensity remained low and relatively constant at Lake Qinghai, suggesting cool, dry, and relatively stable climate conditions. The inferred stable, cold, arid environment of the glacial maximum seems to persist through the Younger Dryas time period, and little or no evidence of a warm interval correlative with the Bølling–Allerød is found in the QH07 record. The transition between the late Pleistocene and the Holocene, about 11,500 cal year BP, was abrupt, more so than indicated by speleothems in eastern China. The Holocene (~11,500 cal year BP to present) was a time of enhanced summer monsoon strength and greater variability, indicating relatively wetter but more unstable climatic conditions than those of the late Pleistocene. The warmest, wettest part of the Holocene, marked by increased organic matter and carbonate contents, occurred from ~11,500 to ~9,000 cal year BP, consistent with maximum summer insolation contrast between 30°N and 15°N. A gradual reduction in precipitation (weakened summer monsoon) is inferred from decreased carbonate content through the course of the Holocene. We propose that changes in the contrast of summer insolation between 30°N and 15°N are the primary control on the Asian monsoon system over glacial/interglacial time scales. Secondary influences may include regional and global albedo changes attributable to ice-cover and vegetation shifts and sea level changes (distance from moisture source in Pacific Ocean). The abruptness of the change at the beginning of the Holocene, combined with an increase in variability, suggest a threshold for the arrival of monsoonal rainfall at the northeastern edge of the Tibetan Plateau.  相似文献   

Some remarks on fabric overprints and constrictional AMS fabrics in igneous rocks     

Karel Schulmann  Josef Ježek 《International Journal of Earth Sciences》2012,101(3):705-714

During the ascent, emplacement and post-emplacement deformation of igneous rocks, two or more phases of deformation that overprint each other are often depicted. These overprints, when magnetic minerals are present, are recorded in magnetic fabric. In this contribution, overprints are studied by means of numerical modeling, following several basic scenarios common to igneous rocks. Biotite and amphibole that occur often together in igneous rocks are considered as carriers of the anisotropy of magnetic susceptibility. Modeling shows that (1) a constrictional fabric with a low degree of anisotropy as commonly recorded in magmatic rocks may result from a deformation overprint and not necessarily from an extensional/transtensional regime, and (2) that the constrictional AMS fabrics originates from orthogonal superimposition of a deformation event on an AMS fabric inherited from earlier magma emplacement history. Therefore, the interpretation of a constrictional fabric must be performed with caution. Numerical modeling may provide a suitable help in strengthening the interpretation of real magnetic fabric data.  相似文献   

Risk occurrences of damaging frosts during the growing season of vegetables in the Elbe River lowland,the Czech Republic     

Vera Potop  Pavel Zahraniček  Luboš Türkott  Petr Štěpánek  Josef Soukup 《Natural Hazards》2014,71(1):1-19

This study has, for the first time, analysed in detail the risk occurrences of the last spring frost, first fall frost and the length of the frost-free period during the growing season of vegetable crops at a high horizontal resolution of 10 km in the Elbe River lowland in the Czech Republic. The daily minimum air temperature from 116 grid points throughout the studied area for the period 1961–2011 was used. The daily values of minimum air temperature ranges of 0 to ?1.1 °C, ?1.2 to ?2.2 °C and below ?2.2 °C were considered to constitute mild, moderate and severe frost intensities, respectively. Firstly, the spatiotemporal variability of the date of the last spring frost, the date of the first fall frost and the length of the frost-free period in the Elbe River lowland is provided. Secondly, the estimation of the probability of a later date in the spring and an earlier date in the fall for various severe frost events and the length of the frost-free period is determined. Third, the changes in the timing of the last and first frosts of the three severities, as well as the length of the frost-free period, are evaluated. From 1961 to 2011, the Elbe River lowland has experienced a decrease in the number of frost days, while the length of the frost-free period between the last spring frost and the first fall frost has increased. The temporal evolution of the frost-free period anomalies displays two distinct periods: a shortening of the frost-free period in the 1960s and an intensified lengthening of the frost-free period since the 1980s. Whereas the latest spring frost has ended on an earlier date across the Elbe River lowland, the first frost date in the fall has generally been delayed to a later date. The dates of the last spring frost have advanced by ?0.21 days per year on average. The fall dates are delayed up to 0.18 days per year, whereas the frost-free period is lengthening by up to 0.39 days per year on average. However, regional frost series suggests that the frost-free period exhibits a large amount of inter-annual variability. In terms of the growth of field vegetables, a late spring frost remains a risk factor, but the degree of risk has decreased. There is a 25 % chance of the occurrence of dangerous spring frosts during the planting of field vegetables after 3rd May, but after 15th May, the risk is only 10 %.  相似文献   

The spatial distribution of the lignite qualitative parameters and variant estimates of coal reserves: the Czech Part of the Vienna Basin     

Jan Jelínek  František Staněk  Lukáš Vebr  Josef Honěk 《International Journal of Earth Sciences》2014,103(4):1113-1123

The aim of this article is to inform about the spatial distribution of the lignite qualitative parameters and total lignite reserves in the Czech Part of the Vienna Basin—The South Moravian Lignite Coalfield (SMLC). The total reserves were estimated on the basis of several composed variant digital models of individual seams in four partial area of SMLC. Calculations of the reserves resulted from the identified spatial distribution of chemical-technological parameters obtained from the thousands analysis of samples taken from more than 4,000 exploration works. The basic model of the deposit was so-called geological model characterising genetic evolution of the deposit and defines the spatial positions of the coal seams. Subsequently developed variant economical models spatially define the selected areas by the quality of lignite expressed by the limits of ash yield. Based on the created models, it was found that in the past just 3–7 % (depending on the variant model) of the total lignite reserves SMLC had been extracted. The presented geological reserves are currently using the existing mining technologies only partially mineable.  相似文献   

Small strain stiffness anisotropy of natural sedimentary clays: review and a model     

David Mašín  Josef Rott 《Acta Geotechnica》2014,9(2):299-312

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