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41.
Konrad Richter 《International Journal of Earth Sciences》1936,27(2):196-206
Zusammenfassung Die Bewegungsrichtungen der diluvialen, nordischen Inlandeismassen können mit ihren Veränderungen des Nachschubes auf Grund ihres Geschiebeinventars in. Norddeutschland festgestellt werden. Derartige Eisstromstriche im großen stehen mit den lokalen Lagerungsverhältnissen diluvialer Schichtpakete des Jungmoränengebietes sehr oft im Widerspruch. Besonders ist das im küstennahen Gebiet Norddeutschlands der Fall. Selten sind genügend große Aufschlüsse vorhanden, die aus der Art der Schichtenlagerung die bis 90° betragenden Abweichungen von der normalen Bewegungsrichtung des Inlandeises erkennen lassen. Es wird daher das Kleingefüge der Geschiebemergel zum Erkennen dieser Abweichungen benutzt. Im allgemeinen wurden die Geschiebe im Eis als Stromlinienkörper bewegt, so daß für Pommern eine Karte beigegeben ist, die eine Glazialschrammenkarte ersetzt. Sie läßt die stärkeren lokalen Schwankungen im küstennahen Gebiet deutlich erkennen. Weitere Einregelungsstudien in fluvioglazialen Sedimenten führten besonders bei Osern zur Möglichkeit, ehemalige Stromrichtungen und -stärken festzustellen. Als Darstellungsmethode werden Gefügediagramme empfohlen, wie sieSander, Rüger u. a. vorwiegend bei Schmelztektoniten benutzten. Die Urstromtäler und großen radialen Rinnen in Norddeutschland bergen noch Probleme, die voraussichtlich mit Einregelungsstudien zu lösen sind. 相似文献
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43.
Bogdan Wszolek Konrad Rudnicki Silvia Masi Paolo De Bernardis Antonio Salvi 《Astrophysics and Space Science》1989,152(1):29-34
We used theIRAS All Sky Maps in order to search for infrared emission in the direction of the Okroy Cloud (R.A.=12h50m, =22°). An enhancement of 100 m diffuse emission is evident in such a region, with an anomalous value of the ratioI
v (100 m)/A
v
; hydrogen 21 cm emission is also present with low radial speed, thus suggesting that the cloud could be a satellite of our Galaxy. 相似文献
44.
Local governmental agencies are increasingly undertaking potentially costly “status‐and‐trends” monitoring to evaluate the effectiveness of stormwater control measures and land‐use planning strategies or to satisfy regulatory requirements. Little guidance is presently available for such efforts, and so we have explored the application, interpretation, and temporal limitations of well‐established hydrologic metrics of runoff changes from urbanization, making use of an unusually long‐duration, high‐quality data set from the Pacific Northwest (USA) with direct applicability to urban and urbanizing watersheds. Three metrics previously identified for their utility in identifying hydrologic conditions with biological importance that respond to watershed urbanization—TQmean (the fraction of time that flows exceed the mean annual discharge), the Richards‐Baker Index (characterizing flashiness relative to the mean discharge), and the annual tally of wet‐season day‐to‐day flow reversals (the total number of days that reverse the prior days' increasing or decreasing trend)—are all successful in stratifying watersheds across a range of urbanization, as measured by total contributing area of urban development. All metrics respond with statistical significance to multidecadal trends in urbanization, but none detect trends in watershed‐scale urbanization over the course of a single decade. This suggests a minimum period over which dependable trends in hydrologic alteration (or improvement) can be detected with confidence. The metrics also prove less well suited to urbanizing watersheds in a semi‐arid climate, with only flow reversals showing a response consistent with prior findings from more humid regions. We also explore the use of stage as a surrogate for discharge in calculating these metrics, recognizing potentially significant agency cost savings in data collection with minimal loss of information. This approach is feasible but cannot be implemented under current data‐reporting practices, requiring measurement of water‐depth values and preservation of the full precision of the original recorded data. With these caveats, however, hydrologic metrics based on stage should prove as or more useful, at least in the context of status‐and‐trends monitoring, as those based on subsequent calculations of discharge. 相似文献
45.
Mike Walker Sigfus Johnsen Sune Olander Rasmussen Trevor Popp Jørgen‐Peder Steffensen Phil Gibbard Wim Hoek John Lowe John Andrews Svante Björck Les C. Cwynar Konrad Hughen Peter Kershaw Bernd Kromer Thomas Litt David J. Lowe Takeshi Nakagawa Rewi Newnham Jakob Schwander 《第四纪科学杂志》2009,24(1):3-17
The Greenland ice core from NorthGRIP (NGRIP) contains a proxy climate record across the Pleistocene–Holocene boundary of unprecedented clarity and resolution. Analysis of an array of physical and chemical parameters within the ice enables the base of the Holocene, as reflected in the first signs of climatic warming at the end of the Younger Dryas/Greenland Stadial 1 cold phase, to be located with a high degree of precision. This climatic event is most clearly reflected in an abrupt shift in deuterium excess values, accompanied by more gradual changes in δ18O, dust concentration, a range of chemical species, and annual layer thickness. A timescale based on multi‐parameter annual layer counting provides an age of 11 700 calendar yr b2 k (before AD 2000) for the base of the Holocene, with a maximum counting error of 99 yr. A proposal that an archived core from this unique sequence should constitute the Global Stratotype Section and Point (GSSP) for the base of the Holocene Series/Epoch (Quaternary System/Period) has been ratified by the International Union of Geological Sciences. Five auxiliary stratotypes for the Pleistocene–Holocene boundary have also been recognised. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
46.
Estimation of low flows in rivers continues to be a vexing problem despite advances in statistical and process‐based hydrological models. We develop a method to estimate minimum streamflow at seasonal to annual timescales from measured streamflow based on regional similarity in the deviations of daily streamflow from minimum streamflow for a period of interest. The method is applied to 1,019 gauged sites in the Western United States for June to December 2015. The gauges were clustered into six regions with distinct timing and magnitude of low flows. A gamma distribution was fit each day to the deviations in specific discharge (daily streamflow divided by drainage area) from minimum specific discharge for gauges in each region. The Kolmogorov–Smirnov test identified days when the gamma distribution was adequate to represent the distribution of deviations in a region. The performance of the gamma distribution was evaluated at gauges by comparing daily estimates of minimum streamflow with estimates from area‐based regression relations for minimum streamflow. Each region had at least 8 days during the period when streamflow measurements would provide better estimates than the regional regression equation, but the number of such days varied by region depending on aridity and homogeneity of streamflow within the region. Synoptic streamflow measurements at ungauged sites have value for estimating minimum streamflow and improving the spatial resolution of hydrological model in regions with streamflow‐gauging networks. 相似文献
47.
49.
Konrad J. K. Büttner 《Theoretical and Applied Climatology》1958,9(1):80-85
Zusammenfassung Laboratoriumsversuche und Feldbeobachtungen zeigen einen unerwartet starken Transport von Wasserdampf in die menschliche Haut,
in getrocknete und in lebende Pflanzen und in trockenen Erdboden hinein. Diese Vorg?nge selbst beruhen offenbar auf Diffusion
und Sorption. Dabei ist für menschliche Haut und für Pflanzen das Entstehen hoher osmotischer Drucke, d. h. niederer Wasserkonzentration,
wahrscheinlich gemacht; doch sind die Ursachen dafür noch unbekannt.
Contribution Number 32 of the Department of Meteorology and Climatology, University of Washington.
Herrn Dr.Anders K. ?ngstr?m zu seinem 70. Geburtstag gewidmet. 相似文献
Summary Laboratory experiments and field observations show surprisingly high amounts of transfer of water vapor into human skin, into dry and living plants, and into dry soil. The processes involved seem to be based on diffusion and sorption. These results may be explained by assuming the existence of high osmotic pressures in skin and in plants; the reason for this concentration is not yet known.
Résumé Des essais de laboratoire et dans la nature montrent un transport inattendu de vapeur d'eau dans la peau humaine, dans des plantes séchées et vivantes ainsi que dans le sol sec. Les phénomènes reposent apparemment sur la diffusion et sur la sorption. En ce qui concerne la peau humaine et les plantes, il est donc probable qu'elles entretiennent des pressions osmotiques élevées; mais la cause en est encore inconnue.
Contribution Number 32 of the Department of Meteorology and Climatology, University of Washington.
Herrn Dr.Anders K. ?ngstr?m zu seinem 70. Geburtstag gewidmet. 相似文献
50.