Die Beziehung zwischen Wind und Oberflächenströmung auf Grund von Triftkartenuntersuchungen     

Heinrich Neumann 《Ocean Dynamics》1966,19(6):253-266

Zusammenfassung Es wurden mehrere Tausend Trifkarten ausgeworfen. Ihr Weg vom Auswurfort zum Fundort wurde mit Hilfe einer elektronischen Rechenanlage durch Modellrechnungen verfolgt, bei denen das Windfeld über der Nordsee vorgegeben war. Die Rechnung wurde so variiert, daß tatsächliche und rechnerische Fundorte der Karten möglichst gut übereinstimmten. (Abb. 3.). Hiernach treiben die Triftkarten in Windrichtung mit 4,2 v. H. der Windgeschwindigkeit. Das nur aus dem Wind gewonnene Bild des Triftweges läßt sich verbessern, wenn zusätzlich Oberflächenströmungen angenommen werden. Durch rechnerische Experimente wurde ein zu diesem Windfaktor passendes Stromfeld für die Nordsee ermittelt (Abb. 15).

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Relation between wind and surface current derived from drift card investigations

Summary Several thousands of drift cards were released. Their route from the place of release to the place of retrieval was traced on an electronic computer by means of model computations where the wind field over the North Sea was preset. The computation was varied so to achieve the best possible agreement of actual and computational places of retrieval (Fig. 3). According to this, the cards are drifting in wind direction at 4.2 per cent of the wind velocity. The drift route exclusively derived from the wind can be improved by assuming, in addition, surface currents. Computational experiments delivered a current distribution in the North Sea corresponding to this wind factor (Fig. 15).

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Les relations entre vent et courant superficiel déduites des études par cartes-flotteurs

Résumé Plusieurs milliers de cartes-flotteurs ayant été lancées, leur trajet du point de lancement au point de recupération a été établi à l'aide d'une calculatrice électronique avec un programme de calcul dans lequel était introduit le champ des vents en mer du Nord. Le calcul était si détaillé que le meilleur accord possible a été trouvé entre les lieux réels et calculés de découverte des cartes (fig. 3). On constate que les cartes sont poussées dans la direction du vent avec une vitesse égale à 4,2% de celle du vent. La représentation obtenue pour les trajets de dérive à partir du vent seul peut être amélioré si on considère en plus les courants superficiels. La représentation calculée montre pour la mer du Nord un champ de courant en accord avec ce facteur de vent (fig. 15).

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Reiner Rummel  Richard H. Rapp 《Journal of Geodesy》1978,52(4):297

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Application of the Priestley-Taylor evaporation model to assess the influence of soil moisture on the evaporation from a large weighing lysimeter and class a pan     

Mukammal  E. I.  Neumann  H. H. 《Boundary-Layer Meteorology》1977,12(2):243-256

The influence of soil moisture on evaporation from a 6-m grass-covered lysimeter and from Class A pans was assessed for one summer using the -parameter of the Priestley-Taylor evaporation model appropriate for the individual surfaces computed on a daily basis. Net radiation over the pan was estimated from above-grass measurements using a correlation established between the two, using measurements made in the previous two summers. Changes in heat storage of the water were considered in the derivation of for the pan. A unique relationship for the particular conditions of the site was determined between the for the lysimeter and soil moisture, approaching 1.29 at soil moisture near field capacity, but decreasing to as low as 0.5 for dry soil. The corresponding relationship for the pan showed more scatter, but this was improved by using 5-day running means of evaporation and stratifying the data in terms of wind speed to yield a family of curves. Values for at wet soil conditions varied from 1.07 for 100 km day^–1 wind run to 1.17 for 250 km day^–1 wind run. For each curve, values of increased by about 20%; as the soil dried. The relationships may be used to reduce observed Class A pan evaporation to equivalent values for wet-soil conditions and to estimate near-surface soil moisture and actual evapotranspiration for this particular site. Extension of the technique to other areas requires derivation of similar relationships appropriate for those other locations  相似文献   

Tveitite,a new calcium yttrium fluoride     

Sveinung Bergstøl  Brenda B. Jensen  Henrich Neumann 《Lithos》1977,10(1):81-87

Tveitite is a new mineral with formula of the type $\text{Ca}{}_{\mathrm{1?x}}\text{(}\text{Y, RE}\text{)}{}_{\mathrm{x}}\text{F}{}_{\mathrm{2+x}}\text{where}\text{x}$ is approximately 0.3. It is found in a cleavelandite pegmatite at Høydalen in Tørdal, Telemark, S. Norway. The sub-cell is thought to be monoclinic, $\text{a}\text{′=3.924,}\text{b}\text{′=3.893,}\text{c}\text{′=5.525, ß=90°26′,}\text{Z}\text{=2}$. The structure is very similar to that of fluorite and can be described in terms of a pseudo-cubic cell $\text{[1}\text{1}\text{0]}{}_0\text{= 5.527, [110]}{}_0\text{= 5.527,}\text{c}\text{= 5.525, α = 90°18′, γ = 89°37′}$ which contains approximately 1[YCa₃F₉]. The mineral shows twinning in at lest three different directions giving a grating structure probably due to high-low inversion. DTA studies show an inversion point at about 670°C. Material heated above this temperature gives X-ray diffraction patterns corresponding to yttrofluorite (a₀ 5.528). The effect of trivalent ions on the stability of fluorite is discussed.  相似文献   

Benefits of greenhouse gas mitigation on the supply,management, and use of water resources in the United States     

K. Strzepek  J. Neumann  J. Smith  J. Martinich  B. Boehlert  M. Hejazi  J. Henderson  C. Wobus  R. Jones  K. Calvin  D. Johnson  E. Monier  J. Strzepek  J.-H. Yoon 《Climatic change》2015,132(1):127-141

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Report of the IAU Working Group on Cartographic Coordinates and Rotational Elements: 2009   总被引：5，自引：0，他引：5  

B. A. Archinal  M. F. A��Hearn  E. Bowell  A. Conrad  G. J. Consolmagno  R. Courtin  T. Fukushima  D. Hestroffer  J. L. Hilton  G. A. Krasinsky  G. Neumann  J. Oberst  P. K. Seidelmann  P. Stooke  D. J. Tholen  P. C. Thomas  I. P. Williams 《Celestial Mechanics and Dynamical Astronomy》2011,109(2):101-135

Every three years the IAU Working Group on Cartographic Coordinates and Rotational Elements revises tables giving the directions of the poles of rotation and the prime meridians of the planets, satellites, minor planets, and comets. This report takes into account the IAU Working Group for Planetary System Nomenclature (WGPSN) and the IAU Committee on Small Body Nomenclature (CSBN) definition of dwarf planets, introduces improved values for the pole and rotation rate of Mercury, returns the rotation rate of Jupiter to a previous value, introduces improved values for the rotation of five satellites of Saturn, and adds the equatorial radius of the Sun for comparison. It also adds or updates size and shape information for the Earth, Mars?? satellites Deimos and Phobos, the four Galilean satellites of Jupiter, and 22 satellites of Saturn. Pole, rotation, and size information has been added for the asteroids (21) Lutetia, (511) Davida, and (2867) ?teins. Pole and rotation information has been added for (2) Pallas and (21) Lutetia. Pole and rotation and mean radius information has been added for (1) Ceres. Pole information has been updated for (4) Vesta. The high precision realization for the pole and rotation rate of the Moon is updated. Alternative orientation models for Mars, Jupiter, and Saturn are noted. The Working Group also reaffirms that once an observable feature at a defined longitude is chosen, a longitude definition origin should not change except under unusual circumstances. It is also noted that alternative coordinate systems may exist for various (e.g. dynamical) purposes, but specific cartographic coordinate system information continues to be recommended for each body. The Working Group elaborates on its purpose, and also announces its plans to occasionally provide limited updates to its recommendations via its website, in order to address community needs for some updates more often than every 3 years. Brief recommendations are also made to the general planetary community regarding the need for controlled products, and improved or consensus rotation models for Mars, Jupiter, and Saturn.  相似文献   

Erratum to: Reports of the IAU Working Group on Cartographic Coordinates and Rotational Elements: 2006 & 2009     

B. A. Archinal  M. F. A��Hearn  A. Conrad  G. J. Consolmagno  R. Courtin  T. Fukushima  D. Hestroffer  J. L. Hilton  G. A. Krasinsky  G. Neumann  J. Oberst  P. K. Seidelmann  P. Stooke  D. J. Tholen  P. C. Thomas  I. P. Williams 《Celestial Mechanics and Dynamical Astronomy》2011,110(4):401-403

The primary poles for (243) Ida and (134340) Pluto and its satellite (134340) Pluto : I Charon were redefined in the IAU Working Group on Cartographic Coordinates and Rotational Elements (WGCCRE) 2006 report (Seidelmann et al. in Celest Mech Dyn Astr 98:155, 2007), and 2009 report (Archinal et al. in Celest Mech Dyn Astr 109:101, 2011), respectively, to be consistent with the primary poles of similar Solar System bodies. However, the WGCCRE failed to take into account the effect of the redefinition of the poles on the values of the rotation angle W at J2000.0. The revised relationships in Table 3 of Archinal et al. 2011) are $$\begin{array}{llll} W & = & 274^{\circ}.05 +1864^{\circ}.6280070\, d\;{\rm for\; (243)\,Ida} \\ W & = & 302^{\circ} .695 + 56^{\circ} .3625225\, d\;{\rm for\; (134340)\,Pluto,\; and}\\ W & = & 122^{\circ} .695 + 56^{\circ} .3625225\, d\;{\rm for\; (134340)\,Pluto : I \,Charon}\end{array}$$ where d is the time in TDB days from J2000.0 (JD2451545.0).  相似文献   

Trace-element mobilization during Ca-metasomatism along a major fluid conduit: Eclogitization of blueschist as a consequence of fluid-rock interaction   总被引：5，自引：0，他引：5  

Andreas Beinlich  Reiner Klemd  Jun Gao 《Geochimica et cosmochimica acta》2010,74(6):1892-298

In the subduction complex of the Tianshan mountains, western China, massive blueschist is cross-cut by an eclogite-facies major fluid conduit surrounded by a reaction zone which is mainly composed of omphacite and garnet. Petrological as well as geochemical evidence suggest that formation of the vein and the eclogitic selvage around the vein was caused by fluid infiltration under peak metamorphic conditions of 21 ± 1.5 kbar and 510 ± 30 °C. The combination of whole-rock with mineral trace-element data as well as mass-balance calculations indicate that substantial differences exist between the unaltered host rock and the part of the system which was altered by fluid-rock interaction. These differences include: (1) depletion of mainly large-ion lithophile elements (LILE) and Li of up to 60% relative to their concentrations in the unaltered host rock; (2) an extreme enrichment of CaO (∼115%), Sr and Pb (>300%) in the altered parts of the vein-wall-rock system; (3) redistribution of heavy rare earth elements (HREE) from partly replaced rutile and recrystallized titanite in the blueschist-eclogite transition zone into newly grown garnet rims in the eclogitic selvage around the vein; (4) transformation of high Nb/Ta rutile into low Nb/Ta titanite which is associated with preferred mobilization of Nb over Ta; and (5) decoupling of Zr and Hf from Nb and Ta; the latter are depleted by ∼30% relative to the unaltered blueschist host rock whereas the former are depleted by only ∼10%. The prerequisite for the transformation of Ca-poor blueschist (6-7 wt.% CaO) into Ca-rich eclogite (up to 13 wt.% CaO) was the infiltration of a Ca-rich fluid. The release of trace elements can be attributed to partitioning of these elements into the passing fluid phase during dissolution-reprecipitation processes in the course of eclogitization. The reactivity of the precursor mineral assemblage and the chemical gradients between the reacting and passing fluid of the conduit are mainly responsible for trace-element mobilization in the studied samples. The suite of trace elements released upon fluid-induced eclogitization of the reactive wall-rock resembles that in island arc magmas showing strong enrichment of LIL elements, strong depletions in HFS elements and intermediate concentrations of REE.  相似文献   

The sensitivity of simulated flow and water quality response to spatial heterogeneity on a hillslope in the Tarrawarra catchment,Australia     

L. N. Neumann  A. W. Western  R. M. Argent 《水文研究》2010,24(1):76-86

Models are widely used to simulate hydrological response and the generation and transport of constituents such as salt, phosphorus, and nitrogen from catchments to streams. Several models use a spatial representation with catchments divided into subcatchments. Variations in land use and other characteristics within subcatchments are represented by spatially lumped hydrologic response units (HRUs) or functional units instead of using fully distributed models. This approach disregards any spatial interaction between HRUs, including their connectivity to each other and to the stream and the influence of these interactions on water and constituent export. A spatially explicit hydrological model (Thales) was used to simulate a variety of theoretical catchments with soils dominated by combinations of infiltration excess, saturation excess, and subsurface stormflow processes and different soil constituent concentrations that were spatially interacting (i.e. located along a hillslope sequence). The modelling results show that the response of both runoff and concentration is sensitive to varying spatial arrangements due to interactions of runoff, infiltration, and chemical processes between the different soil types in many but not all situations. Results highlight the importance of considering connectivity of pathways when modelling hydrological response and constituents export. This is achieved by comparing pairs of simulations and the corresponding differences in the exported loads. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

Preface     

Jakob Flury  Reiner Rummel 《Earth, Moon, and Planets》2004,94(1-2):1-1

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