Luftelektrische Tagesgänge und Massenaustausch im Hochgebirge der Alpen     

H. Israël  H. W. Kasemir  K. Wienert 《Meteorology and Atmospheric Physics》1955,8(1-2):72-94

Zusammenfassung Die luftelektrischen Untersuchungen auf dem Jungfraujoch im Sommer und Herbst 1950, über die vor einiger Zeit in dieser Zeitschrift berichtet worden war, wurden während einer dritten Meßperiode im Winter fortgesetzt und damit zu einer Jahresreihe ergänzt. Trotz ungünstiger Witterung, die den Umfang der Ergebnisse stark einschränkte, konnten die schon früher gezogenen Schlüsse voll bestätigt werden: Die im Sommer starke, im Herbst noch schwach vorhandene systematische Leitfähigkeitsvariation in dieser Alpenhöhe ist im Winter ganz verschwunden; Potentialgefälle und Vertikalstrom verlaufen in ihrem Tagesgang parallel zueinander; im Winter stellt sich somit in der Höhe des Alpenkammes, der jetzt von der Tagesvariation des Massenaustausches offenbar nicht mehr erreicht wird, der ozeanische Typ des luftelektrischen Verhaltens ein.Im Herbst 1950 wurden an einigen Tagen gleichzeitige Registrierungen des Potentialgefälles und des Vertikalstromes auf dem Jungfraujoch und dem 400 km entfernten Sonnblick durchgeführt. Die beiden Elemente zeigen sowohl im mittleren Tagesgang wie auch im einzelnen gute Übereinstimmung. Daraus ist zu entnehmen, daß die auf dem Jungfraujoch gewonnenen Ergebnisse, soweit sie nicht lokal gestört sind, repräsentative Bedeutung für die Kammhöhe der Alpen haben.Eine Studie über Feld und Strom während Niederschlages auf dem Jungfraujoch zeigt, daß trockener Schnee, d. h. Schnee als reines Sublimationsprodukt, stets positiv geladen ist und ein positives Feld (Feld normaler Richtung) erzeugt. Dagegen zeigen feste Niederschlagsteilchen, deren Zustandekommen über den Vergraupelungsprozeß geführt hat (nasser Schnee, Grieseln, Reif- und Frostgraupeln) im allgemeinen negative elektrische Ladung und negative Felder (Feldrichtungsumkehr). Besonders bemerkenswert ist dabei, daß im Sommer in der Regel das Auftreten von Graupeln und Schnee bzw. von Regen und Schnee hintereinander als Zeichen eines sich bildenden Gewitters gewertet werden kann.

---

Summary The investigations on atmospheric electricity of summer and autumn 1950 on the Jungfraujoch have been continued with a third recordingperiod in the winter. By these investigations the former results which are already reported in this review are completed to a full-year-research. In spite of bad weather, which strongly limited the extent of the results, the conclusions drawn from earlier investigations could be entirely verified. In this Alpine altitude the systematic variation of the conductivity, that has been found high in summer and scarcely remarkable in autumn, has completely disappeared in winter. The daily variations of the potential gradient and the air-earth-current are essentially parallel; it accounts for that in winter at the ridge of the Alps the oceanic type of atmospheric electricity is predominant. Obviously, the daily variations of the mass exchange do not reach these high levels in the winter months.In autumn 1950 simultaneous records of the potential gradient and the air-earth-current at Jungfraujoch and at Sonnblick, 400 km distant, have been made during some days. The two elements are in good agreement both with regard to the mean daily variations as to particulars. Hence it follows that the results received at Jungfraujoch are representative for the summit of the Alps except for cases with local disturbances.Furthermore an investigation has been carried out at Jungfraujoch on the electric field and the current during precipitation. It resulted that dry snow, i. e. snow originating by sublimation only, always carries a positive charge and generates an electric field of positive direction. On the contrary, the solid precipitation particles which are formed by graupel formation (wet snow, soft hail, granular snow) carry generally a negative charge and generate an electric field of negative direction. In summer the occurence of snow after soft hail or rain can be taken as a remarkable symptom for developing a thunderstorm.

---

Résumé Les recherches d'électricité atmosphérique effectuées au Jungfraujoch pendant l'été et l'automne 1950 et dont il a été question précédemment dans cette revue ont été complétées par une série hivernale. Malgré un temps défavorable qui a limité les recherches, les résultats précédents ont pu être confirmés. La variation systématique de la conductibilité observée à haute altitude, forte en été et encore faiblement présente en automne, disparaît complètement en hiver. Le gradient de potentiel et le courant vertical présentent des marches diurnes parallèles, c'est-à-dire qu'en hiver, à l'altitude du faîte alpin qui n'est apparemment plus affecté par la variation diurne de l'échange de masse, s'établit le type océanique de l'état électrique de l'atmosphère.En automne 1950 les enregistrements du gradient de potentiel et du courant vertical furent exécultés pendant quelques jours simultanément au Jungfraujoch et au Sonnblick, distant de 400 km. du premier; il y a bon accord entre les mesures des deux éléments, tant pour la variation diurne moyenne que pour les cas isolés. Il s'ensuit que les résultats obtenus au Jungfraujoch, pour autant qu'ils ne sont pas troublés localement, sont représentatifs de la crête des Alpes.Une étude du champ et du courant au Jungfraujoch pendant des précipitations montre que la neige sèche, c'est à dire comme produit pur de sublimation, est toujours chargée positivement et engendre un champ positif (direction normale). Par contre les particules solides issues du grésil (neige mouillée, neige en grains, grésil) sont en général négativement chargées, dans des champs négatifs (direction inversée). Il est en particulier remarquable qu'en été la neige succédant au grésil ou à la pluie soit dans la règle le signe d'un orage en formation.

---

---

Mit 4 Textabbildungen.  相似文献   

Le Capelinhos (Faïal,Açores) vingt ans après son éruption: le modèle éruptif «surtseyen» et les anneaux de tufs hyaloclastiques     

G. Camus  P. Boivin  A. De Goër De Herve  A. Gourgaud  G. Kieffer  J. Mergoil  P. M. Vincent 《Bulletin of Volcanology》1981,44(1):31-42

Phreatomagmatic structures are of two kinds: maars and tuff-rings. Data given by records of Capelinhos activity (Faïal, Açores, 1957–1958), by structures at west point of Faïal island, and by palagonitic breccias of Velay and Cantal areas (France) lead to relate hyaloclastic tuff-rings and shallow subaquatic («surtseyan») eruptions. It is possible to precise causes, characteristics, and mechanism of formation of tuff-rings.  相似文献   

Identification of a magma chamber in the Ghoubbet-Asal rift (Djibouti) from a magnetotelluric experiment     

Daniele Boyer  Jean-Louis Le Mouël  Vincent Courtillot 《Earth and Planetary Science Letters》1981,52(2):372-380

A very broad band (10^?3 to 10⁴ Hz) magnetotelluric investigation of the axial zone of the Ghoubbet-Asal rift (Djibouti) has revealed a shallow (2–4 km) magma chamber which can be mapped in some detail. The suggested roof of the chamber is shallowest very close to the Ardoukoba volcano which was built during the November 1978 rifting episode.  相似文献   

H-Alpha survey of the solar corona at Pic-du-Midi     

Niot  J. M.  Noëns  J. C. 《Solar physics》1997,173(1):53-66

A daily survey of cool material evolution in the inner parts of the solar corona is now performed at the Pic-du-Midi observatory with an H imaging coronagraph. The total field of the coronagraph allows the detection of emission regions all around the solar limb, up to 0.6 solar radius above the limb. This survey is devoted to the study of coronal events and mass motions in a large range of spatial and time scales. The observing modes are associated with a set of numerical treatment processes to produce images which are calibrated in intensity relative to the solar brightness. Position angles and height above the solar limb of the coronal features are determined. Methods of calibration, sky brightness subtraction, and detection of events are discussed.  相似文献   

Chemistry of some Pb-(Cu,Fe)-(Sb,Bi sulfosalts from France and Portugal. Implications for the crystal chemistry of lead sulfosalts in the Cu-poor part of the Pb2S2-Cu2S-Sb2S3-Bi2-Bi2S3 system     

Y. Moëlo  G. Roger  D. Maurel-Palacin  E. Marcoux  A. Laroussi 《Mineralogy and Petrology》1995,53(4):229-250

Electron microprobe analysis of Pb-Cu(Fe)-Sb-Bi sulfosalts from Bazoges and Les Chalanches (France), and Pedra Luz (Portugal), give new data about (Bi, Sb) solid-solution and incorporation of the minor elements Cu, Fe or Ag in jaskolskiite, and in izoklakeite-giessenite and kobellite-tintinaite series. Jaskolskiite from Pedra Luz has high Sb contents (from 17.9 to 20.7 wt.%), leading to the extended general formula: Cu _x Pb_2+x (Sb_1–y Bi _y )_2–x S₅, with 0.10 x 0.22 and 0.19 y 0.41. Fe-free, Bi-rich izoklakeite from Bazoges has high Ag contents (up to 2.2 wt. %), leading to the simplified formula Cu₂Pb₂₂Ag₂(Bi, Sb)₂₂S₅₇; in Les Chalanches it contains less Ag content (1.2 wt.%), but has an excess of Cu that gives the formula: Cu_2.00 (Cu_0.49Ag_1.18)_=1.67Pb_22.70(Bi_12.63Sb_8.99)_=21.62S_57.27.In tintinaite from Pedra Luz, the variation of the Fe/Cu ratio can be explained by the substitution: Cu + (Bi, Sb) Fe + Pb; Fe-free kobellite from Les Chalanches has a Cu-excess, corresponding to the formula Cu_2.81Ag_0.54Pb_9.88(Bi_10.37Sb_5.21)_=15.38S_35.09. Eclarite from the type locality, structurally related to kobellite, shows a Cu excess too. In natural samples of the kobellite homologous series, Fe is positively correlated with Pb, and its contents never exceed that of Cu. Ag substitutes for Pb, together with (Bi, Sb). Taking into account the possibility of Cu excess, but excluding formal Cu²⁺ and Fe³⁺, general formulae can be written:  相似文献   

The Role of Laser Ranging for Calibrating Jason-1: The Corsica Tracking Campaign     

Pierre Exertier  Joë  lle Nicolas  Philippe Berio  David Coulot  Pascal Bonnefond  Olivier Laurain 《Marine Geodesy》2004,27(1):333-340

The French Transportable Laser Ranging System (FTLRS), a highly transportable Satellite Laser Ranging (SLR) instrument, was set up in Corsica (from January to September 2002) for participating to the JASON-1 altimeter verification phase. In addition to the tracking of oceanographic satellite missions and in order to perform an accurate positioning, the FTLRS also acquired laser ranging data on geodetic satellites, STARLETTE and STELLA essentially.

The paper describes the analysis strategy mainly based on the use of a short-arc orbit technique to compute accurate 1 cm local orbits, and then the geocentric positioning (2-3 mm relative to GPS). Finally, we established the JASON-1 absolute calibration value, based on 9 SLR short-arcs (between cycles 1 and 26), at 108.2 ± 8.7 mm; the 10-day repeatability is of 26.1 mm showing that a great accuracy has been reached.  相似文献   

World Symposium on Spherics     

H. Israël 《Pure and Applied Geophysics》1953,25(1):223-224

  相似文献   

Bemerkungen zum Energie-Umsatz im Gewitter     

Prof. Dr. H. Israël 《Pure and Applied Geophysics》1953,24(1):95-103

Zusammenfassung Eine Abschätzung der im Gewitter zum Umsatz kommenden Energiebeträge zeigt, daß die in den elektrischen Phänomenen verbrauchte Energie im Gesamt-Energie-Umsatz nicht ins Gewicht fällt. Zieht man jedoch den Vergleich nur zu dem Teilbetrag des mechanisch-thermodynamischen Energieumsatzes, der sich über den normalen Energie-Umsatz des Wetter- bezw. Austauschgeschehens erhebt, und nimmt versuchsweise für diesen den aus dem Niederschlag allein abgeleiteten Betrag an, so ergibt sich, daß die elektrischen Phänomene etwa 1/4 dieses Betrages beanspruchen. — Die Abschätzung des elektrischen Energie-Umsatzes erlaubt es, die mittlere in einem Erdblitz umgesetzte Energie abzuleiten: Sie ergibt sich zu rund 2000 kWh. Eine noch nicht lösbare Diskrepanz ergibt sich für die Feldstärke unterhalb der Gewitterwolken.

---

Summary By an estimate of the energy budget of the thunderstorm is shown that the energy of electrical activity is entirely negligible in considerations of the whole budget. But if the energy of electrical activity is only compared with that amount of the whole energy which exceeds the normal energy amount of the «Austausch» it can by shown that the electrical phenomena need about 1/4 of this amount (this amount is estimated only from the precipitation). — By the estimation of the electrical energy budget it is possible to give the mean energy of a lightning: about 2000 kWh. In considerations of the potential-gradient under thunderstorm clouds a contradiction is given which can not be solved until now.

  相似文献   

Die Tagesschwankungen der Empfangsfeldstärke bei 17,8 KHz     

dr. H. Israël 《Pure and Applied Geophysics》1948,11(1):78-79

Ohne Zusammenfassung  相似文献   

Transient States in Diagenesis Following the Deposition of a Gravity Layer: Dynamics of O<Subscript>2</Subscript>, Mn,Fe and N-Species in Experimental Units     

Gwénaëlle Chaillou  Pierre Anschutz  Carole Dubrulle  Pascal Lecroart 《Aquatic Geochemistry》2007,13(2):157-172

Biogeochemical processes induced by the deposition of gravity layer in marine sediment were studied in a 295-day experiment. Combining voltammetric microelectrode measurements and conventional analytical techniques, the concentrations of C, O₂, N-species, Mn and Fe have been determined in porewaters and sediments of experimental units. Dynamics of the major diagenetic species following the sudden sediment deposition of few cm-thick layer was explained by alternative diagenetic pathways whose relative importance in marine sediments is still a matter of debate. Time-series results indicated that the diffusion of O₂ from overlying waters to sediments was efficient after the deposition event: anoxic conditions prevailed during the sedimentation. After a few days, a permanent oxic horizon was formed in the top few millimetres. At the same time, the oxidation of Mn²⁺ and then Fe²⁺, which diffused from anoxic sediments, contributed to the surficial enrichment of fresh Mn(III/IV)- and Fe(III)-oxides. Vertical diffusive fluxes and mass balance calculations indicated that a steady-state model described the dynamic of Mn despite the transitory nature of the system. This model was not adequate to describe Fe dynamics because of the multiple sources and phases of Fe²⁺. No significant transfer of Mn and Fe was observed between the underlying sediment and the new deposit: Mn- and Fe-oxides buried at the original interface acted as an oxidative barrier to reduced species that diffused from below. Nitrification processes led to the formation of a NO₃⁻/NO₂⁻ rich horizon at the new oxic horizon. Over the experiment period, NO₃⁻ concentrations were also measured in the anoxic sediment suggesting anaerobic nitrate production.  相似文献