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51.
52.
Dr. R. Reiter Dr. R. Sladkovic Dr. H. -J. Kanter 《Meteorology and Atmospheric Physics》1987,37(2):114-128
Summary The importance of representative and long-term recordings of the trace gases SO2, NO
x
, and NO is explained. Recordings taken under different background conditions and, moreover, simultaneously at neighboring mountain stations, together with other meteorological parameters, are of special interest.The recording stations for the determination of the mentioned gases (a valley station at 740 m a.s.l., a nearby mountain station at 1780 m a.s.l.), the measuring methods, calibration procedures, and zero-air supply are described.The main part deals with the representation of consistent data of trace gases obtained at the two stations (NO only in the valley floor). Special attention was given not only to longterm trends but also to the seasonal and diurnal variations, and to the dependence of the gas concentrations on meteorological parameters. Only on the basis of such a parameterization, the time variations become understandable and the causes can be explained as well as possible. Finally, correlations between the concentrations of the different gas components are shown.With 15 Figures 相似文献
53.
We present a comparison of the zonal mean meridional circulations derived from monthly in situ data (i.e. radiosondes and
ship reports) and from the NCEP/NCAR reanalysis product. To facilitate the interpretation of the results, a third estimate
of the mean meridional circulation is produced by subsampling the reanalysis at the locations where radiosonde and surface
ship data are available for the in situ calculation. This third estimate, known as the subsampled estimate, is compared to
the complete reanalysis estimate to assess biases in conventional, in situ estimates of the Hadley circulation associated
with the sparseness of the data sources (i.e., radiosonde network). The subsampled estimate is also compared to the in situ
estimate to assess the biases introduced into the reanalysis product by the numerical model, initialization process and/or
indirect data sources such as satellite retrievals. The comparisons suggest that a number of qualitative differences between
the in situ and reanalysis estimates are mainly associated with the sparse sampling and simplified interpolation schemes associated
with in situ estimates. These differences include: (1) a southern Hadley cell that consistently extends up to 200 hPa in the
reanalysis, whereas the bulk of the circulation for the in situ and subsampled estimates tends to be confined to the lower
half of the troposphere, (2) more well-defined and consistent poleward limits of the Hadley cells in the reanalysis compared
to the in-situ and subsampled estimates, and (3) considerably less variability in magnitude and latitudinal extent of the
Ferrel cells and southern polar cell exhibited in the reanalysis estimate compared to the in situ and subsampled estimates.
Quantitative comparison shows that the subsampled estimate, relative to the reanalysis estimate, produces a stronger northern
Hadley cell (∼20%), a weaker southern Hadley cell (∼20–60%), and weaker Ferrel cells in both hemispheres. These differences
stem from poorly measured oceanic regions which necessitate significant interpolation over broad regions. Moreover, they help
to pinpoint specific shortcomings in the present and previous in situ estimates of the Hadley circulation. Comparisons between
the subsampled and in situ estimates suggest that the subsampled estimate produces a slightly stronger Hadley circulation
in both hemispheres, with the relative differences in some seasons as large as 20–30%. 6These differences suggest that the
mean meridional circulation associated with the NCEP/NCAR reanalysis is more energetic than observations suggest. Examination
of ENSO-related changes to the Hadley circulation suggest that the in situ and subsampled estimates significantly overestimate
the effects of ENSO on the Hadley circulation due to the reliance on sparsely distributed data. While all three estimates
capture the large-scale region of low-level equatorial convergence near the dateline that occurs during El Nino, the in situ
and subsampled estimates fail to effectively reproduce the large-scale areas of equatorial mass divergence to the west and
east of this convergence area, leading to an overestimate of the effects of ENSO on the zonal mean circulation.
Received: 16 September 1998 / Accepted: 22 April 1999 相似文献
54.
Effect of common point selection on coordinate transformation parameter determination 总被引:2,自引:0,他引:2
The use of satellite positioning techniques commonly requires a transformation from a Conventional Terrestrial coordinate
system to a Geodetic coordinate system, or vice versa. For such a transformation, the main problem is the determination of
transformation parameters between these coordinate systems. The transformation parameters are estimated by a least-squares
process using “common” points, i.e., those points whose coordinates are known in both systems. Therefore, the precision of
so estimated transformation parameters is closely related to certain characteristics of the common points. In this contribution,
we have formulated some theoretical relations between the transformation parameters and the number and the distribution of
common points, and corroborated the theoretical results numerically, using a simulated geodetic network. 相似文献
55.
56.
Prof. Dr. H. G. Scharbert 《Mineralogy and Petrology》1971,16(4):252-267
Zusammenfassung Der Cyanit tritt immer nur in biotitfreien Granuliten auf; in den biotitreicheren kommt Sillimanit vor. Der Cyanit gehört einer frühen Kristallisationsphase im polymetamorphen Ablauf der Granulitgenese an und ist immer älter als der Sillimanit. Cyanit kann sich direkt in Sillimanit umwandeln, meistens jedoch wächst der Sillimanit unabhängig von Cyanit. Die Fe-Gehalte beider Aluminiumsilikate werden angegeben und die Granulitgenese kurz diskutiert.
Mit 8 Abbildungen
Herrn Prof. DDr.H. Wieseneder zum 65. Geburtstag gewidmet. 相似文献
Kyanite and sillimanite in moldanubian granulites
Summary Kyanite always occurs in granulites free from any biotite; in micaceous granulite kyanite is replaced by sillimanite. Kyanite belongs to an early phase of crystallization with in the polymetamorphic genesis of the granulite complexes, and is therefore older than sillimanite. Sillimanite may grow directly out of kyanite, in most cases, however, sillimanite appears to grow independently from kyanite. The iron-contents of both aluminium-silicates are indicated and the genesis of the granulites is shortly discussed.
Mit 8 Abbildungen
Herrn Prof. DDr.H. Wieseneder zum 65. Geburtstag gewidmet. 相似文献
57.
The supersaturation of neon in southeastern Pacific deep sea water is unexpectedly high, 6.6% on the average, while surface waters have values about a factor of two lower. A comparison of neon and argon concentrations indicates the presence of injected air in the deep water. The results from surface samples cannot be reconciled with air injection. 相似文献
58.
Zusammenfassung Die Entstehung von echten Kreuzgürteln kann durch formelle Rotation um die Gefügeachsea oder um die Gefügeachsec erklärt werden; 3 Gefügemerkmale sind für die Analyse dieser beiden Rotationsmöglichkeiten verwendbar: die Lage der optischen Achsen für Rotationsberträge über 30o, das Zonenstück, das die optische Achse und den Spaltflächenpol beinhaltet und die Lage der optischen Undulationszone in bezug auf die Gefügekoordinaten aBc.Die Zweigürtelbilder stellen nach diesen Untersuchungen nur ein instabiles Zwischenglied innerhalb der Quarztektonitgefüge dar.Mit 11 Textabbildungen 相似文献
59.
60.
The petrology and mineralogy of three lavas from the Lupata Gorge, Mocambique, containing primary euhedral analcime phenocrysts, up to 1.5 cm in diameter, as well as potassium feldspar and nepheline phenocrysts, are described. Electron microprobe analyses of these phases and a whole rock analysis of the blairmorite are given. Reference to published and unpublished experimental work indicates that these rocks must have been generated at water pressures between about 5 and 13 kbars, implying depths of origin of between 20 and 50 km. Very rapid transport to the surface and quenching is implied. It is suggested that these indications of the considerable depth of origin of these rocks, taken together with the absence of associated intermediate and basic rocks, lends credence to the hypothesis of D. K. Bailey that the voluminous associations of salic igneous rocks found in parts of the African continent, unaccompanied by associated basic rocks, are explicable in terms of partial melting, under high water pressures, of the lower part of the crust. 相似文献