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Eva Holtanová Jaroslava Kalvová Jiří Mikšovský Petr Pišoft Martin Motl 《Studia Geophysica et Geodaetica》2010,54(3):513-528
In this study we present results of uncertainty analysis in eight regional climate model (RCM) outputs over the area of the
Czech Republic. The RCM simulations come from the EU 5th Framework program project PRUDENCE (Prediction of Regional scenarios
and Uncertainties for Defining EuropeaN Climate change risks and Effects). Using the analysis of variance we have found that
the main source of uncertainty in projected changes of mean seasonal air temperature is the driving global climate model.
In case of precipitation changes, the RCM is the largest source of uncertainty in all seasons except for the spring. With
the second method, the Reliability Averaging method, we have focused on the uncertainty coming from the RCM itself. The results
of both methods showed that the relative contribution of the regional climate model to the uncertainty of simulated mean seasonal
air temperature and precipitation changes is largest in summer and smallest in winter. 相似文献
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Eva Gessner 《Astrophysics and Space Science》1992,196(1):29-43
In this paper we reproduce flat rotation curves of spiral galaxies by discussing a scalar tensor theory of gravity which includes the Higgs field as scalar field. The galaxy density distribution is assumed to be homogeneous or polytropic and in the galaxy core there exists a large concentrated mass. 相似文献
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Inhalt Hornblenden aus Eklogiten und Amphiboliten der südlichen Koralpe werden chemisch und optisch untersucht; außerdem sind die Gitterkonstanten der Hornblenden bestimmt worden.Herrn Prof. Dr.K. H. Scheumann in Verehrung zum 80. Geburtstag gewidmet. 相似文献
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Mario Gaeta Carmela Freda John N. Christensen Luigi Dallai Fabrizio Marra Daniel B. Karner Piergiorgio Scarlato 《Lithos》2006,86(3-4):330-346
We investigated chemical and isotopic compositions of clinopyroxene crystals from well age-constrained juvenile scoria clasts, lava flows, and hypoabyssal magmatic ejecta representative of the whole eruptive history of the Alban Hills Volcanic District. The Alban Hills is a Quaternary ultra-potassic district that was emplaced into thick limestone units along the Tyrrhenian margin of Italy. Alban Hills volcanic products, even the most differentiated, are characterised by low SiO2 content. We suggest that the low silica activity in evolving magmas can be ultimately due to a decarbonation process occurring at the magma/limestone interface. According to the liquid line of descent we propose, the differentiation process is driven by crystallisation of clinopyroxene + leucite ± apatite ± magnetite coupled with assimilation of a small amount of calcite and/or with interaction with crustal CO2. By combining age, chemical data, strontium and oxygen isotopic compositions, and REE content of clinopyroxene, we give insights into the evolution of primitive ultrapotassic magmas of the Alban Hills Volcanic District over an elapsed period of about 600 kyr. Geochemical features of clinopyroxene crystals, consistent with data coming from other Italian ultrapotassic magmas, indicate that Alban Hills primary magmas were generated from a metasomatized lithospheric mantle source. In addition, our study shows that the 87Sr / 86Sr and LREE/HREE of Alban Hills magmas continuously diminished during the 600–35 ka time interval of the Alban Hills eruptive history, possibly reflecting the progressive depletion of the metasomatized mantle source of magmas. 相似文献
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Riassunto Il lavoro riguarda una serie di misure su campioni di 5 tipi diversi di rocce italiane aventi lo scopo di determinare la rispettiva conducibilità termica. Dopo la descrizione dell'apparecchiatura usata, vengono esposti i risultati ottenuti, analizzando in dettaglio l'influenza della scistosità. In base alle misure fatte su campioni di ardesia questa influenza può esprimersi con la formola:k
=k
90+m cos , dove è l'angolo fra la direzione del flusso termico ed il piano di stratificazione, mentrem è una costante caratteristica della scistosità.
Lavoro eseguito con un contributo del Consiglio Nazionale delle Ricerche (Comitato per la Geologia). 相似文献
Summary Experiments made for obtain the thermal conductivity of different kinds of italian rocks are described and discussed. The effect of schistosity was derived for slate rocks and it can be represented with the formula:k =k 90+m cos , where is the angle between the direction of thermal flux and the plain of stratification, whereasm is a constant characterizing the schistosity.
Lavoro eseguito con un contributo del Consiglio Nazionale delle Ricerche (Comitato per la Geologia). 相似文献