Chemical abundances determined from meteor spectra: I. Ratios of the main chemical elements     

Josep M. Trigo‐Rodriguez  Jordi Llorca  Jiri Borovi ka  Juan Fabregat 《Meteoritics & planetary science》2003,38(8):1283-1294

Abstract— Relative chemical abundances of 13 meteoroids were determined by averaging the composition of the radiating gas along the fireball path that originated during their penetration into the Earth's atmosphere. Mg, Fe, Ni, Cr, Mn, and Co abundances, relative to Si, are similar to those reported for CI and CM carbonaceous chondrites and interplanetary dust particles. In contrast, relative abundances of Ca and Ti in meteor spectra indicate that these elements suffer incomplete evaporation processes. The chemical composition of all meteoroids studied in this work differs from that of 1P/Halley dust.  相似文献   

Reconstruction of sea level pressure fields over the Eastern North Atlantic and Europe back to 1500   总被引：3，自引：7，他引：3  

J. Luterbacher  E. Xoplaki  D. Dietrich  R. Rickli  J. Jacobeit  C. Beck  D. Gyalistras  C. Schmutz  H. Wanner 《Climate Dynamics》2002,18(7):545-561

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Mediterranean summer air temperature variability and its connection to the large-scale atmospheric circulation and SSTs   总被引：3，自引：4，他引：3  

E. Xoplaki  J. F. González-Rouco  J. Luterbacher  H. Wanner 《Climate Dynamics》2003,20(7-8):723-739

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The capacity of European Higher Educational Institutions to address threats imposed by natural hazards     

Skevi Perdikou  Jiri Horak  Lena Halounová  Roshani Palliyaguru  Andrew Lees 《Natural Hazards》2016,81(3):1447-1466

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Correction to: Leveraging HPC accelerator architectures with modern techniques — hydrologic modeling on GPUs with ParFlow     

Hokkanen  Jaro  Kollet  Stefan  Kraus  Jiri  Herten  Andreas  Hrywniak  Markus  Pleiter  Dirk 《Computational Geosciences》2021,25(5):1591-1591

Computational Geosciences - A Correction to this paper has been published: https://doi.org/10.1007/s10596-021-10065-y  相似文献   

On the dynamics of photochemical smog over the Swiss Middleland — Results of the first POLLUMET field experiment     

H. Wanner  T. Künzle  U. Neu  B. Ihly  G. Baumbach  B. Steisslinger 《Meteorology and Atmospheric Physics》1993,51(1-2):117-138

Summary The Swiss Middleland is a 300×50 km large plain embedded between the Jura, whose highest elevations are between 1000 and 2000m MSL, and the Alps, whose highest peaks are about 400m MSL. Because this plain is the main residence area of Switzerland with a great variety of emission sources, it is also a location with high photosmog concentrations during the summer months.Within the framework of the Swiss POLLUMET (Air Pollution and Meteorology) programme, an initial summer smog field experiment was carried out during July 1990 with the participation of different research groups from Switzerland and Germany. The measurements showed that the ozone concentrations within the atmospheric boundary layer were remarkably variable. The highest concentrations in the upper mixed layer varied between 100 and 130 ppb. The background ozone concentration in the upper atmospheric boundary layer increased from day to day. However, a clear indication of long-range transport could not be found. Remarkable local and regional concentration differences are not only based on the complex structure of the large emission sources (highways, urban plumes). They are also the result of the interaction of convectively driven motion systems like slope and valley winds and mountain-plain circulation.With 14 Figures  相似文献   

Book reviews     

Oskar Wanner  Peter Perret 《Aquatic Sciences - Research Across Boundaries》1990,52(2):198-198

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The Late Maunder Minimum (1675–1715) – A Key Period forStudying Decadal Scale Climatic Change in Europe     

J. Luterbacher  R. Rickli  E. Xoplaki  C. Tinguely  C. Beck  C. Pfister  H. Wanner 《Climatic change》2001,49(4):441-462

The Late Maunder Minimum (LMM, 1675–1715) denotes the climax of the `Little Ice Age' in Europe with marked climate variability. Investigations into interannual and interdecadal differences of atmospheric circulation between the LMM and the period 1961–1990 have been performedand undertaken based upon sea level pressure (SLP) difference maps, empiricalorthogonal function (EOF) analysis, and objective classification techniques. Since the SLP during the LMM winterwas significantly higher in northeastern Europe but below normal over the central and western Mediterranean, more frequent blocking situations were connected with cold air outbreaks towards central and eastern Europe. Springs were cold and characterized by a southward shift of the mid-latitude storm tracks. Summers in western, central Europe and northern Europe were wetter and slightly cooler than they are today due to a weakerAzores high and a more southerly position of the mean polar front axes. Autumns showed a significantly higher pressure over northern Europe and a lower pressure over continental Europe and the Mediterranean, an indication of an advanced change from summer to winter circulation. It is suggested that the pressure patterns during parts of the LMM might be attributed to the combination of external forcing factors (solar irradiance and volcanic activity) and internal oscillations and couplings in the North Atlantic.  相似文献   

Classification of Transmissivity Magnitude and Variation   总被引：3，自引：0，他引：3  

Jiri Krásný 《Ground water》1993,31(2):230-236

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Traces of structural H2O molecules in baryte     

Anton Beran  Dominik Talla  Zdenek Losos  Jiri Pinkas 《Physics and Chemistry of Minerals》2010,37(3):159-166

The infrared (IR) spectra of gem-quality baryte crystals from different occurrences are characterized by relatively weak but strongly pleochroic absorption bands at 3,280, 3,220, 3,155, and 3,115 cm⁻¹. These bands are assigned to anti-symmetric and symmetric OH stretching vibrations of two types of H₂O molecules localized on vacant Ba sites. The H–H axis of the H₂O I molecule is slightly tilted from the a-axis direction, its twofold axis being nearly parallel to the b-axis, thus defining the plane of the H₂O molecule practically parallel to (001). The H₂O II molecule has its H–H axis parallel to the b-axis direction, with its plane lying approximately parallel to (101). The values of the total water contents of the baryte crystals, calculated on the basis of IR spectroscopic data, are ranging from about 1.7–3.8 wt.ppm. The possible presence of H₃O⁺ ions is also discussed.  相似文献