A numerical integration of a two-level quasi-geostrophic model with variable Rossby parameter     

Dr. A. Huss 《Meteorology and Atmospheric Physics》1967,16(2-3):105-125

Summary Circulation patterns were obtained from a two-level quasi-geostrophic model, in which the Rossby parameter varied with latitude. The initial basic state was characterized by a constant zonal flow at both reference level. The results we re compared with the pattern obtained in a series of experiments with a similar model, in which the Rossby parameter was assumed to be constant. the initial zonal flow in these experiments was assumed in one case to be constant with latitude, in the second casse to have a symmetrical jet centered on the central latitude, and in the thrid case to have its maximum in the southern half of the region. the results of the experiment with a variable Rossby parameter have the closest resemblance to the patterns observed in the real atmospehre. In particular, during the mature stages of the run, the distribution of the zonallyaveraged eddytransport of momentum corresponded quite well to patterns actually observed in the atmosphere.

---

Zusammenfassung Aus einem quasi-geostrophischen Modell mit breitenabhängigem rossby-Parameter wurden Zirkulationsformen errechnet. Der Anfangszustand war durc eine konstante zonale Strömung in zwei Niveaus charakteriseirt. Die Resultate wurden mit Zirkulationen verglichen, die in einer Reihe von Experimenten mit einem ähnlichen Modell, in dem aber der Rossby-Parameter konstant angenommen war, erhalten worden waren. In einemk dieser Fälle wurde angenommen, daß die ursprüngliche zonale Strömung breitenunabhängig war, in einem anderen fall wurde angenommen, daß die Strömung in einem symmetrischen Jetstream über eine mittleren Breite konzentriert war, und in einem dritten Fall wurden angenommen, daß die zonale Strömung ihr Maximum in der südlichen Hälfte des Bereiches hatte. Die Resultate des Experiments mit dem veränderlichen Rossby-Parameter haben die meiste Ähnlichkeit mit Zirkulationsformen in der wirklichen Atmosphäre. Insbesondere paßt die Verteilung des zonal gemittelten Momentumtransports in den Reifestadien des Versuchs gut zu den tatsächlich in der Atmosphäre beobachteten Zirkulationsformen.

---

Résumé On a calculé les formes de circulation découlant d'un modèle quasigéostrophique dont le paramètres de Rossby dépendaient de la latitude. L'état initial en était caractérisé par un courant zonal constant aux deux niveaux. Lels résultats ont été comparés à ceux d'une série d'essais effectués avec un modèle semblable, mais dans lequel les paramètres de Rossby restaient constants. Dans un de ces cas, on a admis que la circulation zonale initiale ne dépendait pas de la latitude. Dans un deuxième, on a simulé un jet symétriquement à une latitude moyenne. Dans un troisième enfin, on a placè le maximum de la circulation zonale dans la moitié sud de l'espace étudié. Les résultats obtenus en partant des essais basés sur un paramètre de Rossby variable sont les plus semblables aux formes de circulation observées réellement dans l'atmosphère. En particulier, la répartition du transport turbulent de la quantité de mouvement — moyenne zonale calculée au stade de maturité de l'essai — est très voisine des formes de circulation observées réellement dans l'atmosphère.

---

---

With 9 Figures

---

The research reported in this document has been sponsored by the Air Force Cambridge Research Laboratories under Grant AF EOAR 63-108 through the European Office of Aerospace Reasearch (OAR), United States Air Force.  相似文献   

Kleinraummeteorologische Studien im Federseegebiet in Strahlungsnächten     

Ed. Huss 《Theoretical and Applied Climatology》1955,6(4):329-352

Zusammenfassung Die vorliegende Studie befaßt sich mit den meteorologischen Vorgängen in einer extrem stabil aufgebauten Kaltluft, wie sie sich in Strahlungsnächten in einem abgeschlossenen Becken mit ebener, horizontaler Talsohle von einigen Kilometern Ausdehnung und im wesentlichen einheitlichem Untergrund einer Moorlandschaft herausbildet.Untersucht wird in erster Linie das Eigenleben der so abgeschlossenen Luftmasse. Dabei zeigt sich, daß der Zustand eines ruhenden Kaltluftsees zumeist erst im Endstadium des nächtlichen Prozesses näherungsweise erreicht wird. Während des größten Teiles der Nacht kommen vielmehr überraschend lebhafte und weitreichende angenähert horizontale Bewegungen leicht zustande, die sich im thermischen Gefüge wie in der Windstruktur kundtun und in dem Verhalten der Nebel- und Dunstfelder sichtbar werden. Unter der Wirkung von Schwerkraft, Druckgefälle und Reibung entstehen einfache Gleitvorgänge, Schaukelbewegungen, fortschreitende Wellen und Seiches, die in einzelnen Beispielen beschrieben werden. Ähnlich wie in der Großraummeteorologie bilden sich durch das quantenhafte Verhalten der Energieumsätze Luftkörperindividuen, deren Deformation hier einfacheren Gesetzen folgt. Trotz ihrer sehr verschiedenen Größenordnung von einigen Dekametern bis zu mehreren Kilometern Ausdehnung bei geringer vertikaler Mächtigkeit zeigen sie auf ihrer Vorderseite einheitlich die Form des vonW. Schmidt in Modellversuchen gefundenen Böenkopfes.Der Einfluß höherer Luftschichten auf die stabilisierte Bodenkaltluft äußert sich in aufgeprägten Wellen und Frendlufteinschüben. Das Beispiel eines nächtlichen Wärmeeinbruchs aus der Höhe wird eingehend beschrieben.

---

Summary The present study deals with the meteorological processes in an extremely stable cold air, formed in clear nights in a confined basin with a plane, horizontal basis extended for some kilometres, and with an essentially uniform ground in a fen-country.In the first place the proper life of the so limited air is studied. It becomes evident, that the state of a resting lake of cold air generally is approximately reached but in the final phase of the night-time process. Moreover, for the greater part of the night surprising active and extended movements of nearly horizontal course easily occur, becoming evident in the structure of wind and temperature stratification and also visible in the behaviour of fog and haze fields. Produced by gravitation, pressure gradient and friction, simple gliding and swinging motions, proceeding waves and seiches result which are described in single examples. Corresponding to the large scale meteorology individual air bodies form by the quantum-like behaviour of energy transformations. Their deformation in this case however, takes course according to simpler laws. In spite of their much various magnitude of the dimensions of some decametres up to several kilometres, while being of small vertical extension they show in their fore part in all cases the shape of a Böenkopf as found byW. Schmidt by model experiments.The influence of upper atmospheric layers on the stable cold air near the ground manifests itself by impressed waves and by influxes of heterogeneous air. An example of a nocturnal invasion of warm air from aloft is described in detail.

---

Résumé Cette étude traite des processus météorologiques dans un air froid d'une stratification extrêmement stable, qui se développent pendant des nuits claires dans un bassin fermé, ayant une base plane et horizontale, d'une étendue de quelques km, et recouverte par le sol essentiellement homogène d'une région marécageuse.C'est surtout la «vie propre» de cette masse d'air limitée qui est étudiée. Il se trouve que, le plus souvent, l'état d'un «lac immobile d'air froid» n'est atteint approximativement qu'à la fin du processus nocturne. Pendant la plus grande partie de la nuit, se produisent au contraire facilement des mouvements presque horizontaux étonnamment actifs et étendus, qui se manifestent dans la structure thermique et du vent, et qui deviennent visibles par le comportement des couches de brouillard et de brume. De simples processus de glissement, des oscillations, des ondes progressives et des seiches se forment sous l'influence de la gravitation, du gradient de pression et du frottement; ils sont décrits par des exemples particuliers. Comme cela se produit dans la météorologie à grande échelle, il se forme des corps atmosphériques individuels à la suite du comportement en quanta des transformations d'énergie. Leur déformation a lieu cependant selon des lois plus simples. En dépit de leur étendue très variable allant de quelques decamètres à plusieurs km, et leur épaisseur peu considérable, ils montrent tous à leur partie antérieure la forme d'un «Böenkopf», pareil à celui queW. Schmidt a trouvé à la suite de ses expériences qu'il fit avec des modèles.L'influence des couches supérieures de l'atmosphère sur l'air froid stable au sol se manifeste par l'impression d'ondes et par des apports d'air étranger. On décrit ensuite en détail une invasion nocturne d'air chaud depuis les couches supérieures.

---

---

Mit 13 Textabbildungen.

---

Herrn Prof. Dr.W. Peppler, zum 70. Geburtstag.  相似文献   

Visual classification of very fine-grained sediments: Evaluation through univariate and multivariate statistics     

Michael Ed. Hohn  Edward B. Nuhfer  Robert J. Vinopal  David S. Klanderman 《Mathematical Geology》1980,12(6):589-606

Classifying very fine-grained rocks through fabric elements provides information about depositional environments, but is subject to the biases of visual taxonomy. To evaluate the statistical significance of an empirical classification of very fine-grained rocks, samples from Devonian shales in four cored wells in West Virginia and Virginia were measured for 15 variables: quartz, illite, pyrite and expandable clays determined by X-ray diffraction; total sulfur, organic content, inorganic carbon, matrix density, bulk density, porosity, silt, as well as density, sonic travel time, resistivity, and -ray response measured from well logs. The four lithologic types comprised: (1) sharply banded shale, (2) thinly laminated shale, (3) lenticularly laminated shale, and (4) nonbanded shale. Univariate and multivariate analyses of variance showed that the lithologic classification reflects significant differences for the variables measured, difference that can be detected independently of stratigraphic effects. Little-known statistical methods found useful in this work included: the multivariate analysis of variance with more than one effect, simultaneous plotting of samples and variables on canonical variates, and the use of parametric ANOVA and MANOVA on ranked data.  相似文献   

Rough seas and statistical deconvolution     

Ed Kragh  Robert Laws 《Geophysical Prospecting》2006,54(4):475-485

The rough‐sea reflection‐response varies (1) along the streamer (2) from shot to shot and (3) with time along the seismic trace. The resulting error in seismic data can be important for time‐lapse imaging. One potential way of reducing the rough‐sea receiver error is to use conventional statistical deconvolution, but special care is needed in the choice of the design and application windows. The well‐known deconvolution problem associated with the non‐whiteness of the reflection series is exacerbated by the requirement of an unusually short design window – a requirement that is imposed by the non‐stationary nature of the rough‐sea receiver wavelet. For a synthetic rough‐sea data set, with a white 1D reflection series, the design window needs to be about 1000 ms long, with an application window about 400 ms long, centred within the design window. Although such a short design window allows the deconvolution operator to follow the time‐variation of the rough‐sea wavelet, it is likely to be too short to prevent the non‐whiteness of the geology from corrupting the operator when it is used on real data. If finely spatial‐sampled traces are available from the streamer, the design window can be extended to neighbouring traces, making use of the spatial correlations of the rough‐sea wavelet. For this ‘wave‐following’ approach to be fruitful, the wind (and hence the dominant wave direction) needs to be roughly along the line of the streamer.  相似文献   

Fe-Ni and Mn-Cr isotopic systems in sulfides from unequilibrated enstatite chondrites     

Yunbin Guan  Gary R. Huss  Laurie A. Leshin 《Geochimica et cosmochimica acta》2007,71(16):4082-4091

In situ measurements of ⁶⁰Fe-⁶⁰Ni and ⁵³Mn-⁵³Cr isotopic systems with an ion microprobe have been carried out for sulfide assemblages from unequilibrated enstatite chondrites (UECs). Evidence for the initial presence of ⁶⁰Fe has been observed in nine sulfide inclusions from three UECs: ALHA77295, MAC88136, and Qingzhen. The inferred initial (⁶⁰Fe/⁵⁶Fe) [(⁶⁰Fe/⁵⁶Fe)₀] ratios show a large variation range, from ∼2 × 10⁻⁷ to ∼2 × 10⁻⁶. The sulfide inclusions with high Fe/Ni ratios yield (⁶⁰Fe/⁵⁶Fe)₀ ratios of ∼(2-7) × 10⁻⁷, similar to most of the (⁶⁰Fe/⁵⁶Fe)₀ values of troilite and pyroxene observed in unequilibrated ordinary chondrites (UOCs). Inclusions with high inferred (⁶⁰Fe/⁵⁶Fe)₀ ratios (∼1-2 × 10⁻⁶) have low Fe/Ni ratios and the magnitude of the ⁶⁰Ni excesses is similar in two MAC88136 assemblages in spite of a difference of a factor of two in their Fe/Ni ratios. The inferred high (⁶⁰Fe/⁵⁶Fe)₀ ratios were probably the result of Fe-Ni re-distribution in the sulfides during later alteration processes.The ⁵³Mn-⁵³Cr system was measured in five of the sulfide assemblages that were examined for their ⁶⁰Fe-⁶⁰Ni systematics. The ⁵³Mn-⁵³Cr isochrons yielded variable initial (⁵³Mn/⁵⁵Mn) [(⁵³Mn/⁵⁵Mn)₀] ratios from ∼(2-7) × 10⁻⁷. There is no obvious correlation between the (⁶⁰Fe/⁵⁶Fe)₀ and (⁵³Mn/⁵⁵Mn)₀ ratios. The variable ⁵³Mn-⁵³Cr isochrons probably also indicate later disturbance to the isotopic systems in these sulfides. Even though no chronological information can be extracted from the ⁶⁰Fe-⁶⁰Ni and ⁵³Mn-⁵³Cr systems in these UEC sulfides, our results indicate that ⁶⁰Fe was present in the enstatite chondrite formation region of the early Solar System.  相似文献   

The geology of the Morro Velho gold deposit in the Archean Rio das Velhas greenstone belt, Quadrilátero Ferrífero, Brazil     

Diogenes Scipioni Vial  Ed DeWitt  Lydia Maria Lobato  Charles H. Thorman 《Ore Geology Reviews》2007,32(3-4):511

The Morro Velho gold deposit, Quadrilátero Ferrífero region, Minas Gerais, Brazil, is hosted by rocks at the base of the Archean Rio das Velhas greenstone belt. The deposit occurs within a thick carbonaceous phyllite package, containing intercalations of felsic and intermediate volcaniclastic rocks and dolomites. Considering the temporal and spatial association of the deposit with the Rio das Velhas orogeny, and location in close proximity to a major NNW-trending fault zone, it can be classified as an orogenic gold deposit. Hydrothermal activity was characterized by intense enrichment in alteration zones of carbonates, sulfides, chlorite, white mica±biotite, albite and quartz, as described in other Archean lode-type gold ores. Two types of ore occur in the deposit: dark gray quartz veins and sulfide-rich gold orebodies. The sulfide-rich orebodies range from disseminated concentrations of sulfide minerals to massive sulfide bodies. The sulfide assemblage comprises (by volume), on average, 74% pyrrhotite, 17% arsenopyrite, 8% pyrite and 1% chalcopyrite. The orebodies have a long axis parallel to the local stretching lineation, with continuity down the plunge of fold axis for at least 4.8 km. The group of rocks hosting the Morro Velho gold mineralization is locally referred to as lapa seca. These were isoclinally folded and metamorphosed prior to gold mineralization. The lapa seca and the orebodies it hosts are distributed in five main tight folds related to F1 (the best examples are the X, Main and South orebodies, in level 25), which are disrupted by NE- to E-striking shear zones. Textural features indicate that the sulfide mineralization postdated regional peak metamorphism, and that the massive sulfide ore has subsequently been neither metamorphosed nor deformed. Lead isotope ratios indicate a model age of 2.82 ± 0.05 Ga for both sulfide and gold mineralization. The lapa seca are interpreted as the results of a pre-gold alteration process and may be divided into carbonatic, micaceous and quartzose types. The carbonatic lapa seca is subdivided into gray and brown subtypes. Non-mineralized, gray carbonatic lapa seca forms the hanging wall to the orebodies, and is interpreted as the product of extreme CO₂ metasomatism during hydrothermal alteration. This dolomitic lapa seca ranges in composition from relatively pure limestone and dolomite to silty limestone and dolomite. The brown carbonatic and micaceous lapa secas are the host rocks to gold. These units are interpreted to correspond to the sheared and hydrothermal products of metamorphosed volcaniclastic and/or volcanic rocks of varying composition from dacitic to andesitic, forming various types of schists and phyllites. The high-grade, massive sulfide orebodies occur at the base of the gray carbonatic lapa seca. Both disseminated mineralization and quartz veins are hosted by micaceous lapa seca. The data are consistent with a model of epigenetic mineralization for the lapa seca, from a hydrothermal fluid derived in part from the Archean basement or older crust material.  相似文献   

Binary coefficients: A theoretical and empirical study   总被引：1，自引：0，他引：1  

Michael Ed. Hohn 《Mathematical Geology》1976,8(2):137-150

Binary coefficients can be assigned to several categories on the basis of algebraic and conceptual properties. The phi coefficient of association is related algebraically to the chi-square statistic for 2-by-2 contingency tables, and use of this coefficient in cluster analysis permits the objective, nonarbitrary partitioning of objects among groups on the basis of previously selected levels of significant, positive association. Similarity, matching, and distance coefficients possess neither conceptual nor operational statistical meaning for many geological data sets. The weighted pair group method and flexible clustering strategy may give an overly conservative partitioning of objects among groups. Clustering by the unweighted pair group method, using the phi coefficient, is recommended for the analysis of biostratigraphic and paleoecologic presence—absence data.  相似文献   

Snow accumulation distribution inferred from time‐lapse photography and simple modelling     

Daniel Farinotti  Jan Magnusson  Matthias Huss  Andreas Bauder 《水文研究》2010,24(15):2087-2097

The spatial and temporal distribution of snow accumulation is complex and significantly influences the hydrological characteristics of mountain catchments. Many snow redistribution processes, such as avalanching, slushflow or wind drift, are controlled by topography, but their modelling remains challenging. In situ measurements of snow accumulation are laborious and generally have a coarse spatial or temporal resolution. In this respect, time‐lapse photography shows itself as a powerful tool for collecting information at relatively low cost and without the need for direct field access. In this paper, the snow accumulation distribution of an Alpine catchment is inferred by adjusting a simple snow accumulation model combined with a temperature index melt model to match the modelled melt‐out pattern evolution to the pattern monitored during an ablation season through terrestrial oblique photography. The comparison of the resulting end‐of‐winter snow water equivalent distribution with direct measurements shows that the achieved accuracy is comparable with that obtained with an inverse distance interpolation of the point measurements. On average over the ablation season, the observed melt‐out pattern can be reproduced correctly in 93% of the area visible from the fixed camera. The relations between inferred snow accumulation distribution and topographic variables indicate large scatter. However, a significant correlation with local slope is found and terrain curvature is detected as a factor limiting the maximal snow accumulation. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

Titanium isotopic compositions of well‐characterized silicon carbide grains from Orgueil (CI): Implications for s‐process nucleosynthesis     

Gary R. Huss  Julie B. Smith 《Meteoritics & planetary science》2007,42(7-8):1055-1075

Abstract— We have measured the titanium isotopic compositions of 23 silicon carbide grains from the Orgueil (CI) carbonaceous chondrites for which isotopic compositions of silicon, carbon, and nitrogen and aluminum‐magnesium systematics had been measured previously. Using the 16 most‐precise measurements, we estimate the relative contributions of stellar nucleosynthesis during the asymptotic giant branch (AGB) phase and the initial compositions of the parent stars to the compositions of the grains. To do this, we compare our data to the results of several published stellar models that employ different values for some important parameters. Our analysis confirms that s‐process synthesis during the AGB phase only slightly modified the titanium compositions in the envelopes of the stars where mainstream silicon carbide grains formed, as it did for silicon. Our analysis suggests that the parent stars of the >1 μm silicon carbide grains that we measured were generally somewhat more massive than the Sun (2–3 M_⊙) and had metallicities similar to or slightly higher than solar. Here we differ slightly from results of previous studies, which indicated masses at the lower end of the range 1.5–3 M_⊙ and metallicities near solar. We also conclude that models using a standard ¹³C pocket, which produces a good match for the main component of s‐process elements in the solar system, overestimate the contribution of the ¹³C pocket to s‐process nucleosynthesis of titanium found in silicon carbide grains. Although previous studies have suggested that the solar system has a significantly different titanium isotopic composition than the parent stars of silicon carbide grains, we find no compelling evidence that the Sun falls off of the array defined by those stars. We also conclude that the Sun does lie on the low‐metallicity end of the silicon and titanium arrays defined by mainstream silicon carbide grains.  相似文献   

RAGLAND,AN LL3.4 CHONDRITE FIND FROM NEW MEXICO     

S.I. Recca  E.R.D. Scott  K. Keil  R.N. Clayton  T.K. Mayeda  G.I Huss  E. Jarosewich  K.S. Weeks  F.A. Hasan  D.W.G. Sears  R. Wieler  P. Signer 《Meteoritics & planetary science》1986,21(2):217-229

The Ragland, New Mexico chondrite was found in 1978, and consists of a single stone of 12.16 kg that broke into three pieces. The stone is moderately weathered and has a pronounced chondritic texture. Bulk composition favors an LL classification, and modal analysis and oxygen isotopic composition are consistent with this. The thermoluminescence sensitivity of 0.056 ± 0.020 normalized to Dhajala, compositional variability of olivine (mean Fa 18.3, σ = 10.1) and low-Ca pyroxene (mean Fs 14.6, σ = 6.7), and Ca concentrations in olivine indicate metamorphic subtype 3.4 ± 0.1. The isotopically heavy oxygen composition, which is characteristic of subtypes 3.0–3.1, may be a primary characteristic and not a result of weathering. Low concentrations of radiogenic ⁴⁰Ar and planetary ³⁶Ar suggest noble gas loss.  相似文献