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1.
Summary The geometry of the principal Upper High (near the Indian Occean) in the 300–100 mb layer appears to account for the Southern Oscillation (S.O.), and models of its behaviour are presented. Significant features of these models include the equatorial points of upper convergence (C) and divergence (D), a pressure discontinuity (CNDS) forming «arcs» and an «enclosure» around the high, and, lastly, encircling «crescents» both outside and inside the enclosure. The geography of the seasonal sucession can thus—in a qualitative manner—be interpreted in the light of known wind and contour patterns near the tropopause. With a few general principles, the established empirical rules of long-range forecasting then follow by deduction. The models and the terminology are useful likewise in the interpretation of solar-terrestrial relations and of climatic fluctuations.  相似文献   

2.
Résumé Des mesures de températures ont été faites dans les Forages du Camp VI et de la Station Centrale, au cours de la Campagne de 1950, des « Expéditions Polaires Françaises 1948–1951 ». Ces mesures ne concordant pas avec celles effectuées par « L'Expédition Allemande au Groenland, A.Wegener, de 1930–31 », le ProfesseurKurt Wegener, dans un rapport intitulé « Température de l'Inlandsis du Groenland », commente les résultats, et, utilisant les résultats des deux Expéditions, établit la distribution de la température dans l'Inlandsis. — Le but de ce rapport est de justifier les mesures de 1950, de donner une limite d'utilisation de ces mesures, et d'expliquer les divergences entre les résultats des deux Expéditions.
Summary In the drilled holes of Camp VI and «Station Centrale», temperature surveys were run during the 1950th expedition of «French Polar Expeditions 1948–1951» (MissionsPaul-Emile Victor). The measurements not being in agreement with those made by the «German Expedition to Greenland A.Wegener 1930–1931» Professor Dr.Kurt Wegener, in a report published in this revue (Die Temperatur in Grönländischen Inlandeis), comments the results and, using the results of both expeditions, gives the temperature distribution in the Greenland Ice-Cap. — The purpose of this report is to justify the 1950th surveys, to state the readings accuracy and to find out the causes of the divergences between the results of both expeditions.
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3.
Zusammenfassung So wie für das Himmelsbild in einer einheitlichen Luftmasse der vertikale Temperaturgradient die wichtigste Rolle spielt, so erweist sich für den Wetterablauf beim Kaltfrontdurchgang die vertikale Temperaturschichtung im Frontbereich von entscheidender Bedeutung. In den Registrierungen der meteorologischen Elemente zeigt sich meist deutlich der Unterschied zwischen «stabilen» und «labilen» Kaltfronten.
Summary As significant the part, played by the vertical lapse rate of temperature in the appearance of the sky in uniform airmasses, as determinant for weather conditions during the passage of a cold front is the vertical lapse rate of temperature in the frontal area. Generally, the recordings of meteorological instruments show a pronounced difference between «stable» and «unstable» coldfronts.
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4.
南印度洋海温偶极子型振荡及其气候影响   总被引:23,自引:2,他引:23       下载免费PDF全文
印度洋海表温度(Sea Surface Temperature,简称SST)的方差分析和相关分析表明南印度洋也存在一个海温偶极子型振荡,并定义了一个南印度洋海表温度异常偶极子指数.夏、秋季(南半球冬、春)的南印度洋偶极子指数与后期热带500hPa和100hPa高度场异常有显著而持续的相关,在冬、春达到最大,并可以持续到次年夏、秋.前期夏、秋季节的南印度洋偶极模对次年我国大陆东部夏季降水异常有显著的影响,对应偶极子正位相,次年夏季印度洋、南海(东亚)夏季风偏弱;副高加强且南撤、西伸,南亚高压偏强且位置偏东,易形成我国长江流域降水偏多,华南降水偏少;负位相年反之.后期冬季西太平洋暖池是联系南印度洋偶极子与次年我国夏季降水异常关系的一条重要途径.南印度洋偶极子表现出了明显的独立于ENSO(El Nio Southern Oscillation,简称ENSO)的特征.  相似文献   

5.
Summary A review is given of the investigations on variations in the general circulation in middle latitudes made byWillett andPetterssen. According toWillett a «high-index» type of circulation pattern with a strong zonal flow has probably caused the recent climatic improvement in the northern latitudes while the «low-index» type with meridional flow would create a cooling off in the same areas. According toPetterssen an other type of «low-index» pattern with a weak zonal flow and strong meridional exchange of air has been the essential cause of the warming up of the northern latitudes in Europe. This implies that the definition of the «low-index» type is not clear and gives rise to misunderstanding. Making use of our experience on glacier retreat in northern Scandinavia it is concluded that thePetterssen type of circulation more probably than the «high-index» type has caused the warming-up in the North Atlantic area from which the retreat of the glaciers has followed.  相似文献   

6.
Two modes of dipole events in tropical Indian Ocean   总被引:1,自引:0,他引:1  
By analyzing the distributions of subsurface temperature and the surface wind stress anomalies in the tropical Pacific and Indian Oceans during the Indian Ocean Dipole (IOD) events, two major modes of the IOD and their formation mechanisms are revealed. (1) The subsurface temperature anomaly (STA) in the tropical Indian Ocean during the IOD events can be described as a “<” -shaped and west-east-oriented dipole pattern; in the east side of the “<” pattern, a notable tongue-like STA extends westward along the equator in the tropical eastern Indian Ocean; while in the west side of the “<” pattern, the STA has opposite sign with two centers (the southern one is stronger than the northern one in intensity) being of rough symmetry about the equator in the tropical mid-western Indian Ocean. (2) The IOD events are composed of two modes, which have similar spatial pattern but different temporal variabilities due to the large scale air-sea interactions within two independent systems. The first mode of the IOD event originates from the air-sea interaction on a scale of the tropical Pacific-Indian Ocean and coexists with ENSO. The second mode originates from the air-sea interaction on a scale of the tropical Indian Ocean and is closely associated with changes in the position and intensity of the Mascarene high pressure. The strong IOD event occurs when the two modes are in phase, and the IOD event weakens or disappears when the two modes are out of phase. Besides, the IOD events are normally strong when either of the two modes is strong. (3) The IOD event is caused by the abnormal wind stress forcing over the tropical Indian Ocean, which results in vertical transports, leading to the upwelling and pileup of seawater. This is the main dynamic processes resulting in the STA. When the anomalous easterly exists over the equatorial Indian Ocean, the cold waters upwell in the tropical eastern Indian Ocean while the warm waters pileup in the tropical western Indian Ocean, hence the thermocline in the tropical Indian Ocean is shallowed in the east and deepened in the west. The off-equator component due to the Coriolis force in the equatorial area causes the upwelling of cold waters and the shallowing of the equatorial India Ocean thermocline. On the other hand, the anomalous anticyclonic circulations and their curl fields located on both sides of the equator, cause the pileup of warm waters in the central area of their curl fields and the deepening of the equatorial Indian Ocean thermocline off the equator. The above three factors lead to the occurrence of positive phase IOD events. When anomalous westerly dominates over the tropical Indian Ocean, the dynamic processes are reversed, and the negative-phase IOD event occurs. Supported by National Natural Science Foundation of China (Grant No. 40776013), National Basic Research Program of China (Grant No. 2006CB403601) and the Knowledge Innovation Project of Chinese Academy of Sciences (Grant No. KZCX-SW-222)  相似文献   

7.
Riassunto L'A. ha qui escogitato una equivalenza bisol-monosol, realizzabile sul terreno, per instaurare «elettrodiaframmi», «elettroparatie» a qualsiasi distanza dagli iniettori di legante. Ne studia gli aspetti fenomenologici principali, corredandoli di grafici utili all'impiego del metodo.
Summary This paper deals with the devising of an equivalence bisol-monosol, which can be performed into soil, in order to carry into effect «electro-diaphragm» and «electro-pilings» at any distance from binding-solution electro-injectors. Principal aspects of phenomena are studied, and graphs useful for applyng the method are given.
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8.
Summary It is shown thatLinke's definition of the «subzonal» solarconstant meets best the problems of the meteorologist.Georgi's «meteorological» solarconstant neglects waveregions very important in biology and in atmospheric heating and has to be rejected. The «astrophysical» solarconstant needs further knowledge of X-rays, radio and corpuscular radiation in units of energy.  相似文献   

9.
Zusammenfassung Eineabsolute «kritische Windgeschwindigkeit» für Prozesse an der Grenzfläche Wasser-Luft scheint nicht zu existieren. Unsere Beobachtungen liefern jedoch Anzeichen für das Vorhandenseinrelativer «kritischer Windgeschwindigkeiten, die vom Ueberströmungsweg, bzw. von der Wellenlaufstrecke abzuhängen scheinen. Diese relativen «kritischen Windgeschwindigkeiten» sind durch folgende-Merkmale gekennzeichnet: Aenderung der Struktur der Meeresoberfläche (glatt-rauh); Umschlag der laminaren Wassergrenzschicht zur Turbulenz; Ueberbrechen der Schwerewellen; Minimum des Widerstandskoeffizienten der Meeresoberfläche.
Summary It seems that there is no absolute «critical wind speed» for air-sea boundary processes. From our observations it may, however, be referred that there are relative values of the «critical wind speed» which seem to depend on the fetch. These relative values of the «critical wind speed» are characterized by the following marks: The sea surface pattern is changed (smooth-rough);, the boundary layer in water turns from laminar to turbulent flow; the gravity waves break; the resistance coefficient of the sea surface has a minimum.
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10.
Zusammenfassung Messwerte russischer Stationen beweisen die Existenz eines «Kontinental-Effektes» bei der maximalen Elektronendichte derF2-Schicht. Im Sommer besteht im Innern des asiatischen Kontinents vorzugsweise eine höhere Konzentration bei Tag; andererseits fehlt dort die sogenannte «Abend-Konzentration».
Summary Results from Russian stations prove the existence of a «Continental effect», on the Maximum electron density of theF2-layer. In summer, in the interior of the asiatic continent a tendency exists for a higher concentration in daytime; on the other side the so-called «evening concentration» is missing there.


HerrnJulius Bartels zum sechzigsten Geburtstag gewidmet.  相似文献   

11.
Summary Observations of gravity over the Palaeozoic rocks of East Carmarthenshire show this to be an area of positive Bouguer anomalies, and throughout the district the isogams are aligned in a «Caledonoid» direction. The regional gradient over the anthracite coalfield can largely be explained in terms of known structure, while the anomaly values in the Towy valley above Llandeilo seem to have been affected by facies variations and contemporaneous volcanic activity. Fairly large anomalies are recorded near Carmarthen, and these may be associated with similar anomalies known near Aberystwyth (Cook & Thirlaway, 1950); they are interpreted as an expression of the Welsh geosyncline. The gravity low discovered in St. George's Channel byBrowne & Cooper (1950) is re-interpreted in terms of the depth of the pre-Palaeozoic floor. There is no marked evidence to indicate the presence of a concealed «granitic» intrusion beneath the coalfield, nor to substantiate the view that there was once a great thickness of Permian or later cover.  相似文献   

12.
Zusammenfassung Gegeben ist ein festes, elastisches Medium, das aus homogenen, isotropen, planparallelen Schichten aufgebaut ist. Im Innern einer Schicht wird ein punktförmiger Störungsherd von Multipolcharakter angenommen. Die Störung setzt zur Zeitt=0 ein. Unter Anwendung der Laplace-Transformation werden nach dem Verfahren vonCagniard «Exponentialkoeffizienten» und «Übertragungsfaktoren» berechnet, die gestatten, die elastischen Verschiebungen der an den verschiedenen Unstetigkeitsflächen reflektierten und gebrochenen Wellen zu bestimmen.
Summary (Elastic waves of multiplet type in a solid consisting of homogeneous isotropic layers with plane parallel boundaries) — An unlimited elastic solid consists of homogeneous isotropic layers, separated by plane parallel boundaries. A point in the interior of one layer is a multiple source of elastic waves. The disturbance begins att=0. By aid of Laplace-transforms, «exponential coefficients» and «transmission factors» have been calculated according to the method shown byCagniard. By aid of the «transmission factors» we can determine the elastic displacements of the waves reflected and refracted at the boundaries.
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13.
Summary A short survey is given of results obtained from «Project Jet Stream» Research Flights. Several features of the atmospheric structure in the vicinity of the jet-stream core seem to be rather characteristic and shall be described in detail. The most prominent among these are: the «Jet-Stream Front»above and below the jet core, stable baroclinic zones on the anticyclonic side of the jet, and an upward bulge of the isentropic surfaces south of the jet stream, the so-called «isentrope hump». Some of theses features seem to have far-reaching implications upon the dynamics of the jet stream.
Zusammenfassung Es wird ein kurzer Überblick über die Ergebnisse einiger «Project-Jet-Stream»-Forschungsflüge gegeben. Einige Merkmale der atmosphärischen Struktur in der Umgebung des Strahlstromkernes scheinen für eine Vielzahl der Fälle charakteristisch zu sein und sollen im folgenden noch näher beschrieben werden. Am deutlichsten treten hervor: Die «Jet-Stream-Front»oberhalb und unterhalb des Strahlstromkernes; stabile und barokline Zonen auf der antizyklonalen Seite des Strahlstromes; eine Aufwölbung der Isentropenflächen südlich der Strahlstromachse, der sogenannte «Isentropenbuckel» («isentrope hump»). Einige dieser Merkmale scheinen weitreichende Einflüsse auf die Dynamik der Strahlströmung zu besitzen.


Paper presented at the I.U.G.G. Meeting in Helsinki, 1960.  相似文献   

14.
Summary After definitions is given an interpolation-like residual method. —It is pointed out the usual disjoining in two parts of the Bouguer-map to be unsatisfactory; in general is the whole «spectrum» to disjoin in several parts from the «noise» to the «regional». — There are someg zz (andg z) methods represented; in this way of representation are the methods without examples direct comparable.  相似文献   

15.
We determined 2D group velocity distribution of Rayleigh waves at periods of 20-150 s in the Antarctic region using a tomographic inversion technique. The data are recorded by both permanent networks and temporary arrays. In East Antarctica the velocities are high at periods of 90-150 s, suggesting that the root of East Antarctica is very deep. The velocities in West Antarctica are low at all periods, which may be related to the volcanic activity and the West Antarctic Rift System. Low velocity anomalies appear at periods of 40-140 s along the Southeastern Indian Ridge and the western part of the Pacific Antarctic Ridge. The velocities are only slightly low around the Atlantic Indian Ridge, Southwestern Indian Ridge, and the eastern part of the Pacific Antarctic Ridge, where the spreading rates are small. Around two hotspots, the Mount Erebus and Balleny Islands, the velocity is low at periods of 50-150 s.  相似文献   

16.
Asian summer monsoon sets in over India after the Intertropical Convergence Zone moves across the equator to the northern hemisphere over the Indian Ocean. Sea surface temperature (SST) anomalies on either side of the equator in Indian and Pacific oceans are found related to the date of monsoon onset over Kerala (India). Droughts in the June to September monsoon rainfall of India are followed by warm SST anomalies over tropical Indian Ocean and cold SST anomalies over west Pacific Ocean. These anomalies persist till the following monsoon which gives normal or excess rainfall (tropospheric biennial oscillation). Thus, we do not get in India many successive drought years as in sub-Saharan Africa, thanks to the ocean. Monsoon rainfall of India has a decadal variability in the form of 30-year epochs of frequent (infrequent) drought monsoons occurring alternately. Decadal oscillations of monsoon rainfall and the well-known decadal oscillation in SST of the Atlantic Ocean (also of the Pacific Ocean) are found to run parallel with about the same period close to 60 years and the same phase. In the active–break cycle of the Asian summer monsoon, the ocean and the atmosphere are found to interact on the time scale of 30–60 days. Net heat flux at the ocean surface, monsoon low-level jetstream (LLJ) and the seasonally persisting shallow mixed layer of the ocean north of the LLJ axis play important roles in this interaction. In an El Niño year, the LLJ extends eastwards up to the date line creating an area of shallow ocean mixed layer there, which is hypothesised to lengthen the active–break (AB) cycle typically from 1 month in a La Niña to 2 months in an El Niño year. Indian monsoon droughts are known to be associated with El Niños, and long break monsoon spells are found to be a major cause of monsoon droughts. In the global warming scenario, the observed rapid warming of the equatorial Indian ocean SST has caused the weakening of both the monsoon Hadley circulation and the monsoon LLJ which has been related to the observed rapid decreasing trend in the seasonal number of monsoon depressions.  相似文献   

17.
Summary In order to interpret the observed features of pressure records produced by waves from large explosions in the earth's atmosphere, the writers have obtained numerical solutions of the homogeneous equations governing acoustic-gravity wave propagation in a stratified compressible fluid. Theoretical dispersion curves and variations of perturbation kinetic energy with altitude are presented for 11 normal modes. It is shown that the step-like character of the phase velocity curves in the velocity-period plane can be interpreted as being the result of interference between two families of normal modes-«quasi-horizontal modes» representing energy propagation in the lower atmosphere (below the ozonosphere) and «quasi-vertical modes» representing energy propagation in the upper atmosphere (above the ozonosphere). The theoretical prediction that several normal modes contribute to the observed barogram traces is verified by Fourier analysis of a number of wave records.Lamont Geological Observatory Contribution No. 611. — This research was supported by National Science Foundation Grant NSF-G-11997, Office of Naval Research Contract Nonr 266 (70), and National Science Foundation Grant NSF-GP-550. — Part of this research was done at the NASA Institute for Space Studies, New York, N. Y.  相似文献   

18.
Zusammenfassung An Rand besonders der Ergebnisse der « Deutschen Grönland-Expedition Alfred Wegener » werden die Zusammenhänge zwischen Luft-Temperatur, Sonnenstrahlung und Boden in einfacher Weise entwickelt.
Summary The results of the « German Grönlandexpedition Alfred Wegener » are used, to give a picture of the relation between air-temperature, solar radiation and the soil.
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19.
Résumé L'auteur expose d'abord les raisons pour lesquelles, dans la majorité des cas, les «noyaux de congélation» proprement dits ne jouent pas au préalable le rôle de «noyaux de condensation». Il décrit ensuite un mécanisme de capture des noyaux glaçogènes présents dans un nuage, mécanisme dû exclusivement à des processus de cinétique moléculaire, où seule intervient la diffusion moléculaire de la vapeur d'eau au cours des transferts occasionnés par les changements de phases. L'efficacité et l'importance de ce mécanisme suffisent pour expliquer la plupart des phénomènes observés en physique des nuages, en particulier lors de l'utilisation des techniques d'ensemencement artificiel mises en oeuvre pour provoquer les précipitations ou dans des buts antigrêligènes.
Summary The author, in the first place, sets out the reasons why, in most cases, the «Freezing nuclei» properly speaking, do not previously play the part of «condensation nuclei». He then describes a mechanism due chiefly to the processes of molecular kinetics in which molecular diffusion alone occurs during the transfer caused by the phase changes. Efficacity and importance of that mechanism are sufficient to explain the majority of the phenomena observed in physics of clouds, particularly with techniques of artificial seeding set to work for producing precipitations or for anti-hail experiments purposes.


Relation présentée au Colloque International sur la Physique des Nuages etses applications à l'Agriculture, Asti, 27–28 Avril 1958.  相似文献   

20.
Summary Several authors have tried to explain the different aspects of pressure waves in water including the phenomenon of «Singing» by assuming another fluid layer below the water column. In this note an attempt has been made to determine the thickness of such a layer.  相似文献   

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