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131.
Dr. Reinhold Steinacker 《Meteorology and Atmospheric Physics》1976,25(2):97-115
Zusammenfassung Starke Zyklogenesen in mittleren Breiten sind mit einer Produktion von zyklonaler Vorticity verbunden. Diese läßt sich mit Hilfe der Scale-Analyse aus horizontaler und vertikaler Windscherung und freiwerdender Kondensationswärme abschätzen. Es wird für den synoptischen Routinedienst eine geeignete Analysenmethode angegeben, die es erlaubt, obige Produktion hinreichend genau zu bestimmen. Anhand aktueller Wetterlagen kann nachgewiesen werden, daß im Winter für eine Zyklogenese der ausschlaggebende Einfluß von der vertikalen Windscherung ausgeht, bei sommerlichen Zyklogenesen hingegen, bei Vorhandensein feuchtwarmer Luftmassen, auch die freiwerdende Kondensationswärme einen großen, oft sogar dominierenden Beitrag liefert.
Mit 10 Abbildungen 相似文献
On production of cyclonal vorticity in cyclogenetic processes
Summary Intensive cyclonic developments in middle latitudes are combined with a production of cyclonal vorticity. With the aid of scale analysis it is possible to estimate this production, if the horizontal and vertical wind shear and the released heat of condensation are known. A simple method of analysis is derived, suitable for the synoptic routine service. This method of analysis is demonstrated on typical cases for cyclonic developments in winter and summer. It is shown that the vertical wind shear has the greatest influence on cyclogenesis in winter, while in summer, due to the higher temperatures, the released heat of condensation often plays the dominating role.
Mit 10 Abbildungen 相似文献
132.
Theoretical and Applied Climatology - Nach einleitenden Angaben über die biologische Tragweite von Wettereinflüssen wird auf die Vorteile einer Annahme von “Indikatoren” zur... 相似文献
133.
134.
P. Möller S. M. Weise M. Tesmer P. Dulski A. Pekdeger U. Bayer F. Magri 《International Journal of Earth Sciences》2008,97(5):1057-1073
Conjoint consideration of distribution of major, rare earth elements (REE) and Y (combined to REY) and of H, O, C, S, Sr isotopes
reveals that four types of groundwater are distinguishable by their chemical composition presented by spider patterns. REY
patterns indicate thermo-saline deep water and two types of shallow saline groundwaters. Presence of connate waters is not
detectable. Sr isotope ratios distinguish three sources of Sr: fast and slow weathering of biotite and K-feldspar in Pleistocene
sediments, respectively, and dissolution of limestones. δ13C(DIC) indicate dissolution of limestone under closed and open system conditions. Numerous samples show δ13C(DIC) > 13‰ which is probably caused by incongruent dissolution of calcite and dolomite. The brines from below 1,000 m represent
mixtures of pre-Pleistocene seawater or its evaporation brines and infiltrated post-Pleistocene precipitation. The shallow
waters represent mixtures of Pleistocene and Recent precipitation salinized by dissolution of evaporites or by mixing with
ascending brines. The distribution of water types is independent on geologic units and lithologies. Even the Tertiary Rupelian
aquiclude does not prevent salinization of the upper aquifer. 相似文献
135.
136.
T. Yegorova U. Bayer H. Thybo Y. Maystrenko M. Scheck-Wenderoth S.B. Lyngsie 《Tectonophysics》2007,429(1-2):133-163
We study the gravity signals from different depth levels in the lithosphere of the Central European Basin System (CEBS). The major elements of the CEBS are the Northern and Southern Permian Basins which include the Norwegian–Danish Basin (NDB), the North-German Basin (NGB) and the Polish Trough (PT). An up to 10 km thick sedimentary cover of Mesozoic–Cenozoic sediments, hides the gravity signal from below the basin and masks the heterogeneous structure of the consolidated crust, which is assumed to be composed of domains that were accreted during the Paleozoic amalgamation of Europe. We performed a three-dimensional (3D) gravity backstripping to investigate the structure of the lithosphere below the CEBS.Residual anomalies are derived by removing the effect of sediments down to the base of Permian from the observed field. In order to correct for the influence of large salt structures, lateral density variations are incorporated. These sediment-free anomalies are interpreted to reflect Moho relief and density heterogeneities in the crystalline crust and uppermost mantle. The gravity effect of the Moho relief compensates to a large extent the effect of the sediments in the CEBS and in the North Sea. Removal of the effects of large-scale crustal inhomogeneities shows a clear expression of the Variscan arc system at the southern part of the study area and the old crust of Baltica further north–east. The remaining residual anomalies (after stripping off the effects of sediments, Moho topography and large-scale crustal heterogeneities) reveal long wavelength anomalies, which are caused mainly by density variations in the upper mantle, though gravity influence from the lower crust cannot be ruled out. They indicate that the three main subbasins of the CEBS originated on different lithospheric domains. The PT originated on a thick, strong and dense lithosphere of the Baltica type. The NDB was formed on a weakened Baltica low-density lithosphere formed during the Sveco-Norwegian orogeny. The major part of the NGB is characterized by high-density lithosphere, which includes a high-velocity lower crust (relict of Baltica passive margin) overthrusted by the Avalonian terrane. The short wavelength pattern of the final residuals shows several north–west trending gravity highs between the Tornquist Zone and the Elbe Fault System. The NDB is separated by a gravity low at the Ringkøbing–Fyn high from a chain of positive anomalies in the NGB and the PT. In the NGB these anomalies correspond to the Prignitz (Rheinsberg anomaly), the Glueckstadt and Horn Graben, and they continue further west into the Central Graben, to join with the gravity high of the Central North Sea. 相似文献
137.
A two-step Lagrange Multiplier test strategy has recently been suggested as a tool to reveal spatial cointegration. The present
paper generalises the test procedure by incorporating control for unobserved heteroscedasticity. Using Monte Carlo simulation,
the behaviour of several relevant tests for spatial cointegration and/or heteroscedasticity is investigated. The two-step
test for spatial cointegration appears to be robust towards heteroscedasticity. While several tests for heteroscedasticity
prove to be inconclusive under certain circumstances, a Lagrange Multiplier test for heteroscedasticity based on spatially
differenced variables is shown to serve well as an indication of heteroscedasticity irrespective of cointegration status.
相似文献
138.
Dominik Höyng Fernando Mazo D’Affonseca Peter Bayer Edson Gomes de Oliveira José Alexandre J. Perinotto Fábio Reis Holger Weiß Peter Grathwohl 《Environmental Earth Sciences》2014,71(7):3081-3094
The Guarani aquifer system (GAS) represents one of the biggest aquifers in the world and is the most relevant groundwater resource in South America. For the first time, by combining field and laboratory measurements, a high-resolution aquifer analog model of fluvial–aeolian sediments of the GAS in São Paulo State (Brazil) is constructed. Three parallel sections of frontal outcrops, 28 m × 5.8 m, and two parallel sections of lateral outcrops, 7 m × 5.8 m, are recorded during open-pit mining of sandy sediments and describe in detail the three-dimensional distribution of the local lithofacies and hydrofacies. Variations of hydraulic conductivity, K, and porosity, n, are resolved on the centimeter scale, and the most permeable units of the fluvial–aeolian facies association are identified. The constructed aquifer analog model shows moderate hydraulic heterogeneity and a mean K value of 1.36 × 10?4 m/s, which is greater than the reported range of K values for the entire GAS in São Paulo State. The results suggest that the examined sedimentary unit constitutes a relevant portion of the GAS in São Paulo State in the context of groundwater extraction and pollution. Moreover, the constructed aquifer analog is considered an ideal basis for future numerical model experiments, aiming at in-depth understanding of the groundwater flow and contaminant transport patterns at this GAS portion or at comparable fluvial–aeolian facies associations. 相似文献