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Journal of geophysical research, Vol.75 No.36. Laboratory investigations of temporary collisions of raindrops / R. List
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.75 No.36 Titre : Laboratory investigations of temporary collisions of raindrops Type de document : articles et extraits Auteurs : R. List, Auteur ; C. F. MacNeil, Auteur ; J. D. McTaggart-Cowan, Auteur Année de publication : 1971 Importance : p.7573-7580 Langues : Français (fre) Résumé : The collision of drops with diameters ranging from 2.0 to 4.5 mm was studied with the velocity differences of the drop pairs equal to those observed in nature. Breakup normally occurred and produced 4.2 fragments on the average. The original two droplets reappear as the larger fragments with very little change in size, and the smaller fragments were formed by the disruption of a joining neck. The collision and breakup are, therefore, basically temporary coalescence. Changes in surface tension did not affect the results. Calculations demonstrated the high frequency of occurrence of such collisions in natural rain. The experimental and numerical data, if expanded, will help to solve the problem of warm rain formation.
in Journal of geophysical research
Journal of geophysical research, Vol.75 No.36. Laboratory investigations of temporary collisions of raindrops [articles et extraits] / R. List, Auteur ; C. F. MacNeil, Auteur ; J. D. McTaggart-Cowan, Auteur . - 1971 . - p.7573-7580.
Langues : Français (fre)
Résumé : The collision of drops with diameters ranging from 2.0 to 4.5 mm was studied with the velocity differences of the drop pairs equal to those observed in nature. Breakup normally occurred and produced 4.2 fragments on the average. The original two droplets reappear as the larger fragments with very little change in size, and the smaller fragments were formed by the disruption of a joining neck. The collision and breakup are, therefore, basically temporary coalescence. Changes in surface tension did not affect the results. Calculations demonstrated the high frequency of occurrence of such collisions in natural rain. The experimental and numerical data, if expanded, will help to solve the problem of warm rain formation.
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Code-barres Cote Support Localisation Section Disponibilité ART-7503-0 ART Document imprimé Bureau chercheur Bureau de CLANET Christophe Disponible Journal of geophysical research, Vol.72. Collision, coalescence, and breakup of large water drops in a vertical wind tunnel / W. R. Cotton
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.72 Titre : Collision, coalescence, and breakup of large water drops in a vertical wind tunnel Type de document : articles et extraits Auteurs : W. R. Cotton, Auteur ; N. R. Gokhale, Auteur Année de publication : 1967 Importance : p.4041-4049 Langues : Français (fre)
in Journal of geophysical research
Journal of geophysical research, Vol.72. Collision, coalescence, and breakup of large water drops in a vertical wind tunnel [articles et extraits] / W. R. Cotton, Auteur ; N. R. Gokhale, Auteur . - 1967 . - p.4041-4049.
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Code-barres Cote Support Localisation Section Disponibilité ART-7508-0 ART Document imprimé Bureau chercheur Bureau de CLANET Christophe Disponible Journal of geophysical research, Vol.75 No.32. Some effects of gravitational tides on a model earth's core / S. T. Suess
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.75 No.32 Titre : Some effects of gravitational tides on a model earth's core Type de document : articles et extraits Auteurs : S. T. Suess, Auteur Année de publication : 1970 Importance : p.6650-6661 Langues : Français (fre) Résumé : A simple two-density earth model, with no dissipation and a point moon, is examined for the net effects of lunar tides and precession on the dynamics of the fluid core. The problem is discussed in terms of the fundamental parameters of the system, which determine the tidal configuration and the precession rate. The resultant fluid flow is generally nontrivial, and has been shown by other experimental and theoretical studies to drive geophysically significant interior deviations from constant vorticity. Criteria are deduced that show when the tides can cancel precessional effects, a case not existing in the earth. Because of the elementary nature of the model, the problem remains completely analytic, although it is thus limited in its relation to the earth.
in Journal of geophysical research
Journal of geophysical research, Vol.75 No.32. Some effects of gravitational tides on a model earth's core [articles et extraits] / S. T. Suess, Auteur . - 1970 . - p.6650-6661.
Langues : Français (fre)
Résumé : A simple two-density earth model, with no dissipation and a point moon, is examined for the net effects of lunar tides and precession on the dynamics of the fluid core. The problem is discussed in terms of the fundamental parameters of the system, which determine the tidal configuration and the precession rate. The resultant fluid flow is generally nontrivial, and has been shown by other experimental and theoretical studies to drive geophysically significant interior deviations from constant vorticity. Criteria are deduced that show when the tides can cancel precessional effects, a case not existing in the earth. Because of the elementary nature of the model, the problem remains completely analytic, although it is thus limited in its relation to the earth.
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Code-barres Cote Support Localisation Section Disponibilité ART-7547-0 ART Document imprimé Bureau chercheur Bureau de LE GAL Patrice Disponible Journal of geophysical research, Vol.79 No.A9. Excitation of edge waves by wave incident on a beach / R. T. Guza
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.79 No.A9 Titre : Excitation of edge waves by wave incident on a beach Type de document : articles et extraits Auteurs : R. T. Guza, Auteur ; R. E. Davis, Auteur Année de publication : 1974 Importance : p.1285-1291 ISBN/ISSN/EAN : 0148-0227 Langues : Français (fre) Résumé : It is shown theoretically that surface waves incident on a beach from deep water can excite edge waves. In particular, a standing wave normally incident on a beach of constant gentle slope is found to transfer energy to edge waves through a weak resonant interaction resulting from an instability of the incident wave with respect to perturbation by edge waves. The analysis is based on the shallow water approximation and ignores the Earth's rotation and consequently applies only to relatively low-mode, high-frequency waves. Coupling coefficients, frequencies, and longshore wave numbers of the excited waves are given. In accordance with Hasselmann's (1967) rule, only edge waves with frequencies lower than the frequency of the incident wave are excited by this mechanism. Viscous effects suggest that an edge wave with a frequency one-half that of the incident wave is preferentially excited. liquid-surface-waves; oceanography-shallow-water-approximation; coupling-coefficients; frequencies-; longshore-wave-numbers; edge-wave-excitation; beach-incidence; ocean-waves
in Journal of geophysical research
Journal of geophysical research, Vol.79 No.A9. Excitation of edge waves by wave incident on a beach [articles et extraits] / R. T. Guza, Auteur ; R. E. Davis, Auteur . - 1974 . - p.1285-1291.
ISSN : 0148-0227
Langues : Français (fre)
Résumé : It is shown theoretically that surface waves incident on a beach from deep water can excite edge waves. In particular, a standing wave normally incident on a beach of constant gentle slope is found to transfer energy to edge waves through a weak resonant interaction resulting from an instability of the incident wave with respect to perturbation by edge waves. The analysis is based on the shallow water approximation and ignores the Earth's rotation and consequently applies only to relatively low-mode, high-frequency waves. Coupling coefficients, frequencies, and longshore wave numbers of the excited waves are given. In accordance with Hasselmann's (1967) rule, only edge waves with frequencies lower than the frequency of the incident wave are excited by this mechanism. Viscous effects suggest that an edge wave with a frequency one-half that of the incident wave is preferentially excited. liquid-surface-waves; oceanography-shallow-water-approximation; coupling-coefficients; frequencies-; longshore-wave-numbers; edge-wave-excitation; beach-incidence; ocean-waves
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Code-barres Cote Support Localisation Section Disponibilité ART-7758-0 ART Document imprimé Bureau chercheur Bureau de KHARIF Christian Disponible Journal of geophysical research, Vol.86, No.C1. Bubble populations and spectra in near-surface / J. Wu
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.86, No.C1 Titre : Bubble populations and spectra in near-surface Type de document : articles et extraits Auteurs : J. Wu, Auteur Année de publication : 1981 Importance : p.457-463 Langues : Français (fre)
in Journal of geophysical research
Journal of geophysical research, Vol.86, No.C1. Bubble populations and spectra in near-surface [articles et extraits] / J. Wu, Auteur . - 1981 . - p.457-463.
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Code-barres Cote Support Localisation Section Disponibilité ART-7899-0 ART Document imprimé Bureau chercheur Bureau de VILLERMAUX Emmanuel Disponible Journal of geophysical research, Vol.109 No.C1-00. Bioluminescence imaging of wave-induced turbulence / M. D. Stokes
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.109 No.C1-00 Titre : Bioluminescence imaging of wave-induced turbulence Type de document : articles et extraits Auteurs : M. D. Stokes, Auteur ; G. B. Deane, Auteur ; M. I. Latz, Auteur ; J. Rohr, Auteur Année de publication : 2004 ISBN/ISSN/EAN : 0148-0227 Langues : Français (fre) Résumé : The ability to measure turbulent processes on small spatial and temporal scales is a long standing problem in physical oceanography. Here we explore a novel means of measuring fluid shear stress using the cell flashing behavior of bioluminescent dinoflagellates. To illustrate this technique, we present estimates of the heterogeneous, time-varying shear stress inside a breaking wave crest. These results have implications for a better understanding of upper ocean wave physics, air-sea gas transfer, and the biology of planktonic near-surface organisms as well as providing a new quantitative fluid visualization tool.
in Journal of geophysical research
Journal of geophysical research, Vol.109 No.C1-00. Bioluminescence imaging of wave-induced turbulence [articles et extraits] / M. D. Stokes, Auteur ; G. B. Deane, Auteur ; M. I. Latz, Auteur ; J. Rohr, Auteur . - 2004.
ISSN : 0148-0227
Langues : Français (fre)
Résumé : The ability to measure turbulent processes on small spatial and temporal scales is a long standing problem in physical oceanography. Here we explore a novel means of measuring fluid shear stress using the cell flashing behavior of bioluminescent dinoflagellates. To illustrate this technique, we present estimates of the heterogeneous, time-varying shear stress inside a breaking wave crest. These results have implications for a better understanding of upper ocean wave physics, air-sea gas transfer, and the biology of planktonic near-surface organisms as well as providing a new quantitative fluid visualization tool.
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Code-barres Cote Support Localisation Section Disponibilité ART-7998-0 ART Document imprimé Bureau chercheur Bureau de LE GAL Patrice Disponible Journal of geophysical research, Vol.99 No.D8. The Landes experiment : biosphere - atmosphere exchanges of ozone and aerosol particles above a pine forest / E. Lamaud
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.99 No.D8 Titre : The Landes experiment : biosphere - atmosphere exchanges of ozone and aerosol particles above a pine forest Type de document : articles et extraits Auteurs : E. Lamaud, Auteur ; Y. Brunet, Auteur ; A. Druilhet, Auteur ; J. Fontan, Auteur ; A. Labatut, Auteur ; A. Lopez, Auteur Année de publication : 1994 Importance : p.16511-16521 Langues : Français (fre) Résumé : An experiment was conducted in a pine forest in southwestern France during late spring 1992. The aim was fourfold: testing various flux measurement methodologies for chemically reactive species; quantifying the exchanges between the forest and the atmosphere; analyzing the involved mechanisms; and studying their influence on the chemistry of the surface boundary layer. This paper presents preliminary results obtained on the dry deposition of ozone and submicronic aerosol particles, measured using eddy correlation. Once properly normalized, the spectra and cospectra of all scalar species exhibit universal shapes over the whole frequency range. However, evidence is provided that under some meteorological conditions the time series of turbulent variables can be affected by nonstationary trends, or low-frequency fluctuations that do not contribute to vertical transfer but whose presence can induce large errors in the calculated fluxes. The time variations of the deposition velocities for ozone and aerosol particles are then presented over 2 days with different meteorological conditions. The deposition velocities are shown to be consistent with other reported studies. Dry deposition of ozone appears to be mainly governed by the stomatal resistance, whereas friction velocity and atmospheric instability in the boundary layer seem to govern the deposition of aerosol particles.
in Journal of geophysical research
Journal of geophysical research, Vol.99 No.D8. The Landes experiment : biosphere - atmosphere exchanges of ozone and aerosol particles above a pine forest [articles et extraits] / E. Lamaud, Auteur ; Y. Brunet, Auteur ; A. Druilhet, Auteur ; J. Fontan, Auteur ; A. Labatut, Auteur ; A. Lopez, Auteur . - 1994 . - p.16511-16521.
Langues : Français (fre)
Résumé : An experiment was conducted in a pine forest in southwestern France during late spring 1992. The aim was fourfold: testing various flux measurement methodologies for chemically reactive species; quantifying the exchanges between the forest and the atmosphere; analyzing the involved mechanisms; and studying their influence on the chemistry of the surface boundary layer. This paper presents preliminary results obtained on the dry deposition of ozone and submicronic aerosol particles, measured using eddy correlation. Once properly normalized, the spectra and cospectra of all scalar species exhibit universal shapes over the whole frequency range. However, evidence is provided that under some meteorological conditions the time series of turbulent variables can be affected by nonstationary trends, or low-frequency fluctuations that do not contribute to vertical transfer but whose presence can induce large errors in the calculated fluxes. The time variations of the deposition velocities for ozone and aerosol particles are then presented over 2 days with different meteorological conditions. The deposition velocities are shown to be consistent with other reported studies. Dry deposition of ozone appears to be mainly governed by the stomatal resistance, whereas friction velocity and atmospheric instability in the boundary layer seem to govern the deposition of aerosol particles.
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Code-barres Cote Support Localisation Section Disponibilité ART-8231-0 ART Document imprimé Bureau chercheur Bureau de PETROFF Alexandre Disponible Journal of geophysical research, Vol.85. On the distribution of the heights of sea waves : some effects of nonlinearity and finite bandwidth / M. S. Longuet-Higgins
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Titre de série : Journal of geophysical research, Vol.85 Titre : On the distribution of the heights of sea waves : some effects of nonlinearity and finite bandwidth Type de document : articles et extraits Auteurs : M. S. Longuet-Higgins, Auteur Année de publication : 1980 Importance : p.1519-1523 Langues : Français (fre) Note de contenu : Texte intégral en ligne sur le site de l'IRPHE
in Journal of geophysical research
Journal of geophysical research, Vol.85. On the distribution of the heights of sea waves : some effects of nonlinearity and finite bandwidth [articles et extraits] / M. S. Longuet-Higgins, Auteur . - 1980 . - p.1519-1523.
Langues : Français (fre)
Note de contenu : Texte intégral en ligne sur le site de l'IRPHE
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Code-barres Cote Support Localisation Section Disponibilité ART-8579-0 ART Document imprimé Bureau chercheur Bureau de KHARIF Christian Disponible Documents numériques
http://www.irphe.univ-mrs.fr/doc/#longuetURL Journal of geophysical research, Vol.105 No.D15. Vertical aerosol fluxes measured by the eddy covariance method and deposition of nucleation mode particles above a scots pine forest in southern Finland / G. Buzorius
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.105 No.D15 Titre : Vertical aerosol fluxes measured by the eddy covariance method and deposition of nucleation mode particles above a scots pine forest in southern Finland Type de document : articles et extraits Auteurs : G. Buzorius, Auteur ; P. Keronen, Auteur ; M. Kulmala, Auteur ; J. M. Mäkelä, Auteur ; U. Rannik, Auteur ; T. Versala, Auteur Année de publication : 2000 Importance : p.19905-19916 Langues : Français (fre)
in Journal of geophysical research
Journal of geophysical research, Vol.105 No.D15. Vertical aerosol fluxes measured by the eddy covariance method and deposition of nucleation mode particles above a scots pine forest in southern Finland [articles et extraits] / G. Buzorius, Auteur ; P. Keronen, Auteur ; M. Kulmala, Auteur ; J. M. Mäkelä, Auteur ; U. Rannik, Auteur ; T. Versala, Auteur . - 2000 . - p.19905-19916.
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Code-barres Cote Support Localisation Section Disponibilité ART-8580-0 ART Document imprimé Bureau chercheur Bureau de PETROFF Alexandre Disponible Journal of geophysical research, Vol.85 No.C3. Narrow-band nonlinear sea waves / M. A. Tayfun
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.85 No.C3 Titre : Narrow-band nonlinear sea waves Type de document : articles et extraits Auteurs : M. A. Tayfun, Auteur Année de publication : 1980 Importance : p.1548-1552 Langues : Français (fre)
in Journal of geophysical research
Journal of geophysical research, Vol.85 No.C3. Narrow-band nonlinear sea waves [articles et extraits] / M. A. Tayfun, Auteur . - 1980 . - p.1548-1552.
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Code-barres Cote Support Localisation Section Disponibilité ART-8885-0 ART Document imprimé Bureau chercheur Bureau de KHARIF Christian Disponible Journal of geophysical research, Vol.100 No.B12. On the effect of continents on mantle convection / L. Guillou
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.100 No.B12 Titre : On the effect of continents on mantle convection Type de document : articles et extraits Auteurs : L. Guillou, Auteur ; C. Jaupart, Auteur Année de publication : 1995 Importance : p.24217-24238 Langues : Français (fre) Résumé : At the Earth's surface, continents and oceans impose different thermal boundary conditions at the top of the mantle. Laboratory experiments are used to investigate the consequences of this for mantle convection. The upper boundary of the experimental tank was made of copper plates enforcing a fixed temperature and had a conductive lid of finite width in the middle. Beneath this lid, the thermal boundary condition was of the ``mixed'' type, with a Biot number depending on the dimensions and thermal conductivity of the lid. Experimental values of the Biot number were scaled to Earth values. Experiments were run for a large range of Rayleigh numbers, from 104 to 107, and for several lid widths. The effects of temperature-dependent viscosity and of the shape of the lid were investigated. At steady state, in all cases, there is an upwelling beneath the conductive lid, which feeds two symmetrical and elongated convective cells. Three different dynamic regimes were identified as a function of Rayleigh number, independently of the lid width. At Rayleigh numbers lower than 1.2 105, the upwelling is steady both in geometry and temperature structure. At Rayleigh numbers between 1.2 105 and 2 106, this central upwelling is intermittent. At larger values of the Rayleigh number, there is no longer a simple upwelling structure, but a set of small plumes rising together and distorted by a cellular circulation of large horizontal extent. Thus the conductive lid always imposes a large-scale flow pattern. The length of these convective cells is a function of lid width. It is equal to the lid width at large values and decreases to the Rayleigh-Bénard value as the lid width decreases to zero. A fluid loop model explains the most important features of this form of convection. The cell length is such that the upwelling temperature is minimized for a given Rayleigh number and lid width and is an increasing function of lid width and a decreasing function of Rayleigh number. Transient experiments demonstrate that the large-scale flow structure develops rapidly with even small horizontal temperature differences. Implications for the Earth are that large-scale convection cells exist in conditions which, in the absence of continents, would probably lead to a chaotic convection pattern dominated by plumes. At high Rayleigh number, continental breakup is effected by a large-scale line upwelling structure which includes a number of individual plumes.
in Journal of geophysical research
Journal of geophysical research, Vol.100 No.B12. On the effect of continents on mantle convection [articles et extraits] / L. Guillou, Auteur ; C. Jaupart, Auteur . - 1995 . - p.24217-24238.
Langues : Français (fre)
Résumé : At the Earth's surface, continents and oceans impose different thermal boundary conditions at the top of the mantle. Laboratory experiments are used to investigate the consequences of this for mantle convection. The upper boundary of the experimental tank was made of copper plates enforcing a fixed temperature and had a conductive lid of finite width in the middle. Beneath this lid, the thermal boundary condition was of the ``mixed'' type, with a Biot number depending on the dimensions and thermal conductivity of the lid. Experimental values of the Biot number were scaled to Earth values. Experiments were run for a large range of Rayleigh numbers, from 104 to 107, and for several lid widths. The effects of temperature-dependent viscosity and of the shape of the lid were investigated. At steady state, in all cases, there is an upwelling beneath the conductive lid, which feeds two symmetrical and elongated convective cells. Three different dynamic regimes were identified as a function of Rayleigh number, independently of the lid width. At Rayleigh numbers lower than 1.2 105, the upwelling is steady both in geometry and temperature structure. At Rayleigh numbers between 1.2 105 and 2 106, this central upwelling is intermittent. At larger values of the Rayleigh number, there is no longer a simple upwelling structure, but a set of small plumes rising together and distorted by a cellular circulation of large horizontal extent. Thus the conductive lid always imposes a large-scale flow pattern. The length of these convective cells is a function of lid width. It is equal to the lid width at large values and decreases to the Rayleigh-Bénard value as the lid width decreases to zero. A fluid loop model explains the most important features of this form of convection. The cell length is such that the upwelling temperature is minimized for a given Rayleigh number and lid width and is an increasing function of lid width and a decreasing function of Rayleigh number. Transient experiments demonstrate that the large-scale flow structure develops rapidly with even small horizontal temperature differences. Implications for the Earth are that large-scale convection cells exist in conditions which, in the absence of continents, would probably lead to a chaotic convection pattern dominated by plumes. At high Rayleigh number, continental breakup is effected by a large-scale line upwelling structure which includes a number of individual plumes.
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Code-barres Cote Support Localisation Section Disponibilité ART-8907-0 ART Document imprimé Bureau chercheur Bureau de PONCET Sébastien Disponible Journal of geophysical research, Vol.110 No.C4, A. An estimate of the gas transfer rate from oceanic bubbles derived from multibeam sonar observations of a ship wake / T. C. Weber
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.110 No.C4, A Titre : An estimate of the gas transfer rate from oceanic bubbles derived from multibeam sonar observations of a ship wake Type de document : articles et extraits Auteurs : T. C. Weber, Auteur ; D. L. Bradley, Auteur ; A. P. Lyons, Auteur Année de publication : 2005 Langues : Français (fre) Résumé : Measurements of gas transfer rates from bubbles have been made in the laboratory, but these are difficult to extrapolate to oceanic bubbles where populations of surfactants and particulate matter that inhibit gas transfer are different. Measurements at sea are complicated by unknown bubble creation rates that make it difficult to uniquely identify and observe the evolution of individual bubble clouds. One method that eliminates these difficulties is to measure bubbles in a ship wake where bubble creation at any given location is confined to the duration of the passing ship. This method assumes that the mechanisms slowing the gas dissolution of naturally created bubbles act in a similar manner to slow the dissolution of bubbles in a ship wake. A measurement of the gas transfer rate for oceanic bubbles using this method is reported here. A high-frequency upward-looking multibeam echosounder was used to measure the spatial distribution of bubbles in the wake of a twin screw 61-m research vessel. Hydrodynamic forcing functions are extracted from the multibeam data and used in a bubble cloud evolution model in which the gas transfer rate is treated as a free parameter. The output of model runs corresponding to different gas transfer rates is compared to the time-dependent wake depth observed in the data. Results indicating agreement between the model and the data show that the gas transfer rate must be approximately 15 times less then it would be for surfactant-free bubbles in order to explain the bubble persistence in the wake.
in Journal of geophysical research
Journal of geophysical research, Vol.110 No.C4, A. An estimate of the gas transfer rate from oceanic bubbles derived from multibeam sonar observations of a ship wake [articles et extraits] / T. C. Weber, Auteur ; D. L. Bradley, Auteur ; A. P. Lyons, Auteur . - 2005.
Langues : Français (fre)
Résumé : Measurements of gas transfer rates from bubbles have been made in the laboratory, but these are difficult to extrapolate to oceanic bubbles where populations of surfactants and particulate matter that inhibit gas transfer are different. Measurements at sea are complicated by unknown bubble creation rates that make it difficult to uniquely identify and observe the evolution of individual bubble clouds. One method that eliminates these difficulties is to measure bubbles in a ship wake where bubble creation at any given location is confined to the duration of the passing ship. This method assumes that the mechanisms slowing the gas dissolution of naturally created bubbles act in a similar manner to slow the dissolution of bubbles in a ship wake. A measurement of the gas transfer rate for oceanic bubbles using this method is reported here. A high-frequency upward-looking multibeam echosounder was used to measure the spatial distribution of bubbles in the wake of a twin screw 61-m research vessel. Hydrodynamic forcing functions are extracted from the multibeam data and used in a bubble cloud evolution model in which the gas transfer rate is treated as a free parameter. The output of model runs corresponding to different gas transfer rates is compared to the time-dependent wake depth observed in the data. Results indicating agreement between the model and the data show that the gas transfer rate must be approximately 15 times less then it would be for surfactant-free bubbles in order to explain the bubble persistence in the wake.
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Code-barres Cote Support Localisation Section Disponibilité ART-8964-0 ART Document imprimé Bureau chercheur Bureau de CAILLE François Disponible Journal of geophysical research, Vol.83 No.C. The effect of internal waves on surface wind waves. 2, Theoretical analysis / B. A. Hughes
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.83 No.C Titre : The effect of internal waves on surface wind waves. 2, Theoretical analysis Type de document : articles et extraits Auteurs : B. A. Hughes, Auteur Année de publication : 1978 Importance : p.455-465 Langues : Français (fre)
in Journal of geophysical research
Journal of geophysical research, Vol.83 No.C. The effect of internal waves on surface wind waves. 2, Theoretical analysis [articles et extraits] / B. A. Hughes, Auteur . - 1978 . - p.455-465.
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Code-barres Cote Support Localisation Section Disponibilité ART-9067-0 ART Document imprimé Bureau chercheur Bureau de CAULLIEZ Guillemette Disponible Journal of geophysical research, Vol.104 No.B1. Tsunami detection by satellite altimetry / E. A. Okal
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Titre de série : Journal of geophysical research, Vol.104 No.B1 Titre : Tsunami detection by satellite altimetry Type de document : articles et extraits Auteurs : E. A. Okal, Auteur ; P. Heinrich, Auteur ; A. Piatanesi, Auteur Année de publication : 1999 Importance : p.599-615 Langues : Français (fre)
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Journal of geophysical research, Vol.104 No.B1. Tsunami detection by satellite altimetry [articles et extraits] / E. A. Okal, Auteur ; P. Heinrich, Auteur ; A. Piatanesi, Auteur . - 1999 . - p.599-615.
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Code-barres Cote Support Localisation Section Disponibilité ART-9068-0 ART Document imprimé Bureau chercheur Bureau de CAULLIEZ Guillemette Disponible Journal of geophysical research, Vol.101 No.B3. Dynamics of explosive degassing of magma: Observations of fragmenting two-phase flows / H. M. Mader
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.101 No.B3 Titre : Dynamics of explosive degassing of magma: Observations of fragmenting two-phase flows Type de document : articles et extraits Auteurs : H. M. Mader, Auteur ; J. C. Phillips, Auteur ; R. S. J. Sparks, Auteur ; B. Sturtevant, Auteur Année de publication : 1996 Importance : p.5547-5560 Langues : Français (fre) Résumé : Liquid explosions, generated by rapid degassing of strongly supersaturated liquids, have been investigated in the laboratory with a view to understanding the basic physical processes operating during bubble nucleation and growth and the subsequent behavior of the expanding two-phase flow. Experiments are carried out in a shock tube and are monitored by high-speed photography and pressure transducers. Theoretical CO2 supersaturations up to 455 times the ambient saturation concentration are generated by a chemical reaction; K2CO3 solution is suddenly injected into an excess of HCl solution in such a way as to mix the two solutions rapidly. Immediately after the injection event, a bubble nucleation delay of a few milliseconds is followed by rapid nucleation and explosive expansion of CO2 bubbles forming a highly heterogeneous foam. Enhanced diffusion due to advection in the flow coupled with continuous mixing of the reactants, and hence on-going bubble nucleation after injection, generates an increasingly accelerating flow until the reactants become depleted at peak accelerations of around 150 g and velocities of about 15 m s-1. Stretching of the accelerating two-phase mixture enhances the mixing. Liberation of CO2 vapor is spatially inhomogeneous leading to ductile fragmentation occurring throughout the flow in regions of greatest gas release as the consequence of the collision and stretching of fluid streams. The violence of the eruptions is controlled by using different concentrations of the HCl and K2CO3 solutions, which alters the CO2 supersaturation and yield and also the efficiency of the mixing process. Peak acceleration is proportional to theoretical supersaturation. Pressure measurements at the base of the shock tube show an initial nucleation delay and a pressure pulse related to the onset of explosive bubble formation. These chemically induced explosions differ from liquid explosions created in other experiments. In explosions caused by sudden depressurization of CO2-saturated water, the bubbles nucleate uniformly throughout the liquid in a single nucleation event. Subsequent bubble growth causes the two-phase mixture to be accelerated upward at nearly constant accelerations. Explosively boiling liquids, in which heterogeneous nucleation is suppressed, experience an evaporation wave which propagates down into the liquid column at constant average velocity. Fragmentation occurs at the sharply defined leading edge of the wavefront. The chemical flows effectively simulate highly explosive volcanic eruptions as they are comparable in terms of flow densities, velocities, accelerations, and in the large range of scales present. The large accelerations cause strong extensional strain and longitudinal deformation. Comparable deformation rates in volcanic systems could be sufficient to approach conditions for brittle fragmentation. Tube pumice is a major component of plinian deposits and ignimbrites and preserves evidence of accelerating flow conditions. © American Geophysical Union 1996
in Journal of geophysical research
Journal of geophysical research, Vol.101 No.B3. Dynamics of explosive degassing of magma: Observations of fragmenting two-phase flows [articles et extraits] / H. M. Mader, Auteur ; J. C. Phillips, Auteur ; R. S. J. Sparks, Auteur ; B. Sturtevant, Auteur . - 1996 . - p.5547-5560.
Langues : Français (fre)
Résumé : Liquid explosions, generated by rapid degassing of strongly supersaturated liquids, have been investigated in the laboratory with a view to understanding the basic physical processes operating during bubble nucleation and growth and the subsequent behavior of the expanding two-phase flow. Experiments are carried out in a shock tube and are monitored by high-speed photography and pressure transducers. Theoretical CO2 supersaturations up to 455 times the ambient saturation concentration are generated by a chemical reaction; K2CO3 solution is suddenly injected into an excess of HCl solution in such a way as to mix the two solutions rapidly. Immediately after the injection event, a bubble nucleation delay of a few milliseconds is followed by rapid nucleation and explosive expansion of CO2 bubbles forming a highly heterogeneous foam. Enhanced diffusion due to advection in the flow coupled with continuous mixing of the reactants, and hence on-going bubble nucleation after injection, generates an increasingly accelerating flow until the reactants become depleted at peak accelerations of around 150 g and velocities of about 15 m s-1. Stretching of the accelerating two-phase mixture enhances the mixing. Liberation of CO2 vapor is spatially inhomogeneous leading to ductile fragmentation occurring throughout the flow in regions of greatest gas release as the consequence of the collision and stretching of fluid streams. The violence of the eruptions is controlled by using different concentrations of the HCl and K2CO3 solutions, which alters the CO2 supersaturation and yield and also the efficiency of the mixing process. Peak acceleration is proportional to theoretical supersaturation. Pressure measurements at the base of the shock tube show an initial nucleation delay and a pressure pulse related to the onset of explosive bubble formation. These chemically induced explosions differ from liquid explosions created in other experiments. In explosions caused by sudden depressurization of CO2-saturated water, the bubbles nucleate uniformly throughout the liquid in a single nucleation event. Subsequent bubble growth causes the two-phase mixture to be accelerated upward at nearly constant accelerations. Explosively boiling liquids, in which heterogeneous nucleation is suppressed, experience an evaporation wave which propagates down into the liquid column at constant average velocity. Fragmentation occurs at the sharply defined leading edge of the wavefront. The chemical flows effectively simulate highly explosive volcanic eruptions as they are comparable in terms of flow densities, velocities, accelerations, and in the large range of scales present. The large accelerations cause strong extensional strain and longitudinal deformation. Comparable deformation rates in volcanic systems could be sufficient to approach conditions for brittle fragmentation. Tube pumice is a major component of plinian deposits and ignimbrites and preserves evidence of accelerating flow conditions. © American Geophysical Union 1996
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Code-barres Cote Support Localisation Section Disponibilité ART-9171-0 ART Document imprimé Bureau chercheur Bureau de VILLERMAUX Emmanuel Disponible Journal of geophysical research, Vol.102 No.B1. Fragmentation of basaltic melt in the course of explosive volcanism / B. Zimanowski
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.102 No.B1 Titre : Fragmentation of basaltic melt in the course of explosive volcanism Type de document : articles et extraits Auteurs : B. Zimanowski, Auteur ; R. Büttner, Auteur ; H.-G. Häfele, Auteur ; V. Lorenz, Auteur Année de publication : 1997 Importance : p.803-814 Langues : Français (fre) Résumé : With the aim to enhance interpretation of fragmentation mechanisms during explosive volcanism from size and shape characteristics of pyroclasts experimental studies have been conducted using remelted volcanic rock (olivine-melilitite). The melt was fragmented and ejected from a crucible by the controlled release of pressurized air volumes (method 1) or by controlled generation of phreatomagmatic explosions (Molten Fuel Coolant Interaction (MFCI); method 2). Both methods were adjusted so that the ejection history of the melt was identical in both cases. The experiments demonstrate that exclusively during MFCI, angular particles in the grain size interval 32 to 130 µm are generated that show surface textures dominated by cracks and pitting. The physical process of their generation is described as a brittle process acting at cooling rates of >106 K/s, at stress rates well above 3 GPa/m2, and during ~700 µs. In this time period the emission of intense shock waves in the megahertz range was detected, releasing kinetic energy of >1000 J. By both experimental methods, three more types of particles were produced in addition, which could be identified and related to the acceleration and ejection history of the melt: spherical particles, elongated particles, and Pele’s hair. Abundance and grain size distribution of these particles were found to be proportional to the rate of acceleration and the speed of ejection but were not influenced by the experimental method used. Pele’s hair occurred at ejection speeds of >75 m/s.© 1997 American Geophysical Union
in Journal of geophysical research
Journal of geophysical research, Vol.102 No.B1. Fragmentation of basaltic melt in the course of explosive volcanism [articles et extraits] / B. Zimanowski, Auteur ; R. Büttner, Auteur ; H.-G. Häfele, Auteur ; V. Lorenz, Auteur . - 1997 . - p.803-814.
Langues : Français (fre)
Résumé : With the aim to enhance interpretation of fragmentation mechanisms during explosive volcanism from size and shape characteristics of pyroclasts experimental studies have been conducted using remelted volcanic rock (olivine-melilitite). The melt was fragmented and ejected from a crucible by the controlled release of pressurized air volumes (method 1) or by controlled generation of phreatomagmatic explosions (Molten Fuel Coolant Interaction (MFCI); method 2). Both methods were adjusted so that the ejection history of the melt was identical in both cases. The experiments demonstrate that exclusively during MFCI, angular particles in the grain size interval 32 to 130 µm are generated that show surface textures dominated by cracks and pitting. The physical process of their generation is described as a brittle process acting at cooling rates of >106 K/s, at stress rates well above 3 GPa/m2, and during ~700 µs. In this time period the emission of intense shock waves in the megahertz range was detected, releasing kinetic energy of >1000 J. By both experimental methods, three more types of particles were produced in addition, which could be identified and related to the acceleration and ejection history of the melt: spherical particles, elongated particles, and Pele’s hair. Abundance and grain size distribution of these particles were found to be proportional to the rate of acceleration and the speed of ejection but were not influenced by the experimental method used. Pele’s hair occurred at ejection speeds of >75 m/s.© 1997 American Geophysical Union
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Code-barres Cote Support Localisation Section Disponibilité ART-9172-0 ART Document imprimé Bureau chercheur Bureau de VILLERMAUX Emmanuel Disponible Journal of geophysical research, Vol.94 No.B11. Particle size distributions and the sequential fragmentation/transport theory applied to volcanic ash / K. H. Wohletz
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.94 No.B11 Titre : Particle size distributions and the sequential fragmentation/transport theory applied to volcanic ash Type de document : articles et extraits Auteurs : K. H. Wohletz, Auteur ; W. K. Brown, Auteur ; M. F. Sheridan, Auteur Année de publication : 1989 Importance : p.15703-15721 Langues : Français (fre) Résumé : The assumption that distributions of mass versus size interval for fragmented materials fit the log normal distribution is empirically based and has historical roots in the late 19th century. Other often used distributions (e.g., Rosin-Rammler, Weibull) are also empirical and have the general form for mass per size interval: n(l)=kla exp(-lß), where n(l) represents the number of particles of diameter l, l is the normalized particle diameter, and k, a, and ß are constants. We describe and extend the sequential fragmentation distribution to include transport effects upon observed volcanic ash size distributions. The sequential fragmentation/transport (SFT) distribution is also of the above mathematical form, but it has a physical basis rather than empirical. The SFT model applies to a particle-mass distribution formed by a sequence of fragmentation (comminution) and transport (size sorting) events acting upon an initial mass m’: n(x, m)=C n(x’, m’)p( ) dx’ dm’, where x’ denotes spatial location along a linear axis, C is a constant, and integration is performed over distance from an origin to the sample location and mass limits from 0 to m. We show that the probability function that models the production of particles of different size from an initial mass and sorts that distribution, p( ), is related to mg, where g (noted as for fragmentation processes) is a free parameter that determines the location, breadth, and skewness of the distribution: g ( ) must be greater than ~1, and it increases from that value as the distribution matures with greater number of sequential steps in the fragmentation or transport process; is expected to be near ~1 for ‘‘sudden’’ fragmentation mechanisms such as single-event explosions and transport mechanisms that are functionally dependent upon particle mass. This free parameter will be move positive for evolved fragmentation mechanisms such as ball milling and complex transport processes such as saltation. The SFT provides better fits to many types of volcanic ash samples than does the log normal curve. Modeling of the SFT shows its similarity to the log normal curve on size frequency histograms; it differs by its variable skewness controlled by . Skewed distributions are typical of many volcanic ash samples, and characterization of them by the SFT allows interpretation of eruptive and transport mechanisms. © American Geophysical Union 1989
in Journal of geophysical research
Journal of geophysical research, Vol.94 No.B11. Particle size distributions and the sequential fragmentation/transport theory applied to volcanic ash [articles et extraits] / K. H. Wohletz, Auteur ; W. K. Brown, Auteur ; M. F. Sheridan, Auteur . - 1989 . - p.15703-15721.
Langues : Français (fre)
Résumé : The assumption that distributions of mass versus size interval for fragmented materials fit the log normal distribution is empirically based and has historical roots in the late 19th century. Other often used distributions (e.g., Rosin-Rammler, Weibull) are also empirical and have the general form for mass per size interval: n(l)=kla exp(-lß), where n(l) represents the number of particles of diameter l, l is the normalized particle diameter, and k, a, and ß are constants. We describe and extend the sequential fragmentation distribution to include transport effects upon observed volcanic ash size distributions. The sequential fragmentation/transport (SFT) distribution is also of the above mathematical form, but it has a physical basis rather than empirical. The SFT model applies to a particle-mass distribution formed by a sequence of fragmentation (comminution) and transport (size sorting) events acting upon an initial mass m’: n(x, m)=C n(x’, m’)p( ) dx’ dm’, where x’ denotes spatial location along a linear axis, C is a constant, and integration is performed over distance from an origin to the sample location and mass limits from 0 to m. We show that the probability function that models the production of particles of different size from an initial mass and sorts that distribution, p( ), is related to mg, where g (noted as for fragmentation processes) is a free parameter that determines the location, breadth, and skewness of the distribution: g ( ) must be greater than ~1, and it increases from that value as the distribution matures with greater number of sequential steps in the fragmentation or transport process; is expected to be near ~1 for ‘‘sudden’’ fragmentation mechanisms such as single-event explosions and transport mechanisms that are functionally dependent upon particle mass. This free parameter will be move positive for evolved fragmentation mechanisms such as ball milling and complex transport processes such as saltation. The SFT provides better fits to many types of volcanic ash samples than does the log normal curve. Modeling of the SFT shows its similarity to the log normal curve on size frequency histograms; it differs by its variable skewness controlled by . Skewed distributions are typical of many volcanic ash samples, and characterization of them by the SFT allows interpretation of eruptive and transport mechanisms. © American Geophysical Union 1989
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Code-barres Cote Support Localisation Section Disponibilité ART-9173-0 ART Document imprimé Bureau chercheur Bureau de VILLERMAUX Emmanuel Disponible Journal of geophysical research, Vol.99 No.B8. On the vesicularity of pumice / N. Thomas
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.99 No.B8 Titre : On the vesicularity of pumice Type de document : articles et extraits Auteurs : N. Thomas, Auteur ; C. Jaupart, Auteur ; S. Vergniolle, Auteur Année de publication : 1994 Importance : p.15633-15644 Langues : Français (fre) Résumé : We develop a physical framework for the evolution of vesicular magma fragments after their formation by fragmentation in explosive eruptions. These fragments are carried by a gaseous jet through the volcanic conduit and into the atmosphere and are thus subjected to a decrease of pressure and temperature. We derive equations for the evolution of void fraction, internal gas pressure and temperature as a function of time and position in the fragment. The driving terms for the evolution are the pressure and temperature history external to the fragment. We show that a magma fragment can expand significantly before being quenched. The influence of melt viscosity is introduced as a dimensionless number that relates melt viscosity, pressure drop between fragmentation within the conduit and expansion in the atmosphere, and duration of the pressure drop. For melt viscosities larger than 109 Pa s, corresponding to high-silica-content rhyolitic melt with small amounts of dissolved water, expansion of vesicles is negligible so that quenched pumice samples record the state of vesicular magma at the moment of fragmentation. Over the viscosity range of 106 to 109 Pa s, the amount of vesicularity is a function of melt viscosity and the history of external pressure. For viscosities lower than 106 Pa s, melt viscosity is not important, and gas pressure within vesicles is always close to the external pressure. Available data for four Plinian deposits show that pumice vesicularity varies significantly both as a function of time during an eruption and between eruptions. For the magma compositions and volatile contents of the Bishop Tuff, United States; Taupo, New Zealand; and Minoan, Santorini, eruptions, the void fraction of pumice is predicted to be a decreasing function of melt viscosity, in agreement with observations. During an eruption, a change of fragmentation conditions will produce a small difference in pumice vesicularity, so that a systematic change in the average vesicularity within a pumice deposit may record a change of eruption dynamics. © American Geophysical Union 1994
in Journal of geophysical research
Journal of geophysical research, Vol.99 No.B8. On the vesicularity of pumice [articles et extraits] / N. Thomas, Auteur ; C. Jaupart, Auteur ; S. Vergniolle, Auteur . - 1994 . - p.15633-15644.
Langues : Français (fre)
Résumé : We develop a physical framework for the evolution of vesicular magma fragments after their formation by fragmentation in explosive eruptions. These fragments are carried by a gaseous jet through the volcanic conduit and into the atmosphere and are thus subjected to a decrease of pressure and temperature. We derive equations for the evolution of void fraction, internal gas pressure and temperature as a function of time and position in the fragment. The driving terms for the evolution are the pressure and temperature history external to the fragment. We show that a magma fragment can expand significantly before being quenched. The influence of melt viscosity is introduced as a dimensionless number that relates melt viscosity, pressure drop between fragmentation within the conduit and expansion in the atmosphere, and duration of the pressure drop. For melt viscosities larger than 109 Pa s, corresponding to high-silica-content rhyolitic melt with small amounts of dissolved water, expansion of vesicles is negligible so that quenched pumice samples record the state of vesicular magma at the moment of fragmentation. Over the viscosity range of 106 to 109 Pa s, the amount of vesicularity is a function of melt viscosity and the history of external pressure. For viscosities lower than 106 Pa s, melt viscosity is not important, and gas pressure within vesicles is always close to the external pressure. Available data for four Plinian deposits show that pumice vesicularity varies significantly both as a function of time during an eruption and between eruptions. For the magma compositions and volatile contents of the Bishop Tuff, United States; Taupo, New Zealand; and Minoan, Santorini, eruptions, the void fraction of pumice is predicted to be a decreasing function of melt viscosity, in agreement with observations. During an eruption, a change of fragmentation conditions will produce a small difference in pumice vesicularity, so that a systematic change in the average vesicularity within a pumice deposit may record a change of eruption dynamics. © American Geophysical Union 1994
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Code-barres Cote Support Localisation Section Disponibilité ART-9174-0 ART Document imprimé Bureau chercheur Bureau de VILLERMAUX Emmanuel Disponible Journal of geophysical research, Vol.102 No.B6. Expansion and quenching of vesicular magma fragments in Plinian eruptions / E. Kaminsky
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.102 No.B6 Titre : Expansion and quenching of vesicular magma fragments in Plinian eruptions Type de document : articles et extraits Auteurs : E. Kaminsky, Auteur ; C. Jaupart, Auteur Année de publication : 1997 Importance : p.12187-12203 Langues : Français (fre) Résumé : The conditions of pumice generation in Plinian eruptions are studied. A physical model describes the behavior of gas bubbles in a magma fragment which is carried upward in a volcanic conduit and an atmospheric eruption column. The effects of pressure release and cooling are calculated for a range of eruption conditions. The magma fragment expands in the conduit and stops expanding soon after leaving the vent, when a thin viscous rind forms against the cold mixture of magmatic gas and air. This rind prevents further volume changes. Pumice vesicularity is a function of the decompression rate in the conduit, which depends on ascent velocity and fragmentation depth. It is also sensitive to the cooling rate in the atmospheric column, which depends on vent radius and mass discharge rate. Different fragments follow different trajectories in the column and are subjected to different cooling rates. This generates a range of vesicularities which reflects the eruptive conditions. All else being equal, pumice vesicularity increases as magma viscosity decreases. These predictions are consistent with observations. Pumices provide quantitative constraints on conduit flow conditions and mass discharge rate. These concepts are applied to two Plinian eruptions. Vesicularity values for the Bishop Tuff, Long Valley caldera, require a mass discharge rate between 108 and 109 kg s-1. Vesicularity variations during Plinian phase 1 of the Minoan eruption, Santorini, are explained by the conduit radius increasing from about 30 m to 120 m. Both cases require large decompression rates in the eruption conduit, suggesting that flow pressures were close to lithostatic values.© 1997 American Geophysical Union
in Journal of geophysical research
Journal of geophysical research, Vol.102 No.B6. Expansion and quenching of vesicular magma fragments in Plinian eruptions [articles et extraits] / E. Kaminsky, Auteur ; C. Jaupart, Auteur . - 1997 . - p.12187-12203.
Langues : Français (fre)
Résumé : The conditions of pumice generation in Plinian eruptions are studied. A physical model describes the behavior of gas bubbles in a magma fragment which is carried upward in a volcanic conduit and an atmospheric eruption column. The effects of pressure release and cooling are calculated for a range of eruption conditions. The magma fragment expands in the conduit and stops expanding soon after leaving the vent, when a thin viscous rind forms against the cold mixture of magmatic gas and air. This rind prevents further volume changes. Pumice vesicularity is a function of the decompression rate in the conduit, which depends on ascent velocity and fragmentation depth. It is also sensitive to the cooling rate in the atmospheric column, which depends on vent radius and mass discharge rate. Different fragments follow different trajectories in the column and are subjected to different cooling rates. This generates a range of vesicularities which reflects the eruptive conditions. All else being equal, pumice vesicularity increases as magma viscosity decreases. These predictions are consistent with observations. Pumices provide quantitative constraints on conduit flow conditions and mass discharge rate. These concepts are applied to two Plinian eruptions. Vesicularity values for the Bishop Tuff, Long Valley caldera, require a mass discharge rate between 108 and 109 kg s-1. Vesicularity variations during Plinian phase 1 of the Minoan eruption, Santorini, are explained by the conduit radius increasing from about 30 m to 120 m. Both cases require large decompression rates in the eruption conduit, suggesting that flow pressures were close to lithostatic values.© 1997 American Geophysical Union
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Code-barres Cote Support Localisation Section Disponibilité ART-9175-0 ART Document imprimé Bureau chercheur Bureau de VILLERMAUX Emmanuel Disponible Journal of geophysical research, Vol.70. The Workman-Reynolds Effect and Ionic Transfer Processes at the Ice-Solution Interface / G. W. Gross
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Titre de série : Journal of geophysical research, Vol.70 Titre : The Workman-Reynolds Effect and Ionic Transfer Processes at the Ice-Solution Interface Type de document : articles et extraits Auteurs : G. W. Gross, Auteur Année de publication : 1965 Importance : p.2291 Langues : Français (fre)
in Journal of geophysical research
Journal of geophysical research, Vol.70. The Workman-Reynolds Effect and Ionic Transfer Processes at the Ice-Solution Interface [articles et extraits] / G. W. Gross, Auteur . - 1965 . - p.2291.
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Code-barres Cote Support Localisation Section Disponibilité ART-9458-0 ART Document imprimé Bureau chercheur Bureau de DESCHAMPS Julien Disponible Journal of geophysical research, Vol.77 No.27. Flow patterns in breaking bubbles / F. Maclntyre
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Titre de série : Journal of geophysical research, Vol.77 No.27 Titre : Flow patterns in breaking bubbles Type de document : articles et extraits Auteurs : F. Maclntyre, Auteur Année de publication : 1972 Importance : p.5211-5228 Langues : Français (fre)
in Journal of geophysical research
Journal of geophysical research, Vol.77 No.27. Flow patterns in breaking bubbles [articles et extraits] / F. Maclntyre, Auteur . - 1972 . - p.5211-5228.
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Code-barres Cote Support Localisation Section Disponibilité ART-9545-0 ART Document imprimé Bureau chercheur Bureau de ANTKOWIAK Arnaud Disponible Journal of geophysical research, Vol.106 No.D4. Sampling error in eddy correlation flux measurements / P. L. Finkelstein
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Titre de série : Journal of geophysical research, Vol.106 No.D4 Titre : Sampling error in eddy correlation flux measurements Type de document : articles et extraits Auteurs : P. L. Finkelstein, Auteur ; P. S. Sims, Auteur Année de publication : 2001 Importance : p.3503-3510 Langues : Français (fre)
in Journal of geophysical research
Journal of geophysical research, Vol.106 No.D4. Sampling error in eddy correlation flux measurements [articles et extraits] / P. L. Finkelstein, Auteur ; P. S. Sims, Auteur . - 2001 . - p.3503-3510.
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Code-barres Cote Support Localisation Section Disponibilité ART-9558-0 ART Document imprimé Bureau chercheur Bureau de AMIELH Muriel Disponible Journal of geophysical research, Vol.108 No.D17. Interpretation of aerosol particle fluxes over a pine forest: Dry deposition and random errors / U. Rannick
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Titre de série : Journal of geophysical research, Vol.108 No.D17 Titre : Interpretation of aerosol particle fluxes over a pine forest: Dry deposition and random errors Type de document : articles et extraits Auteurs : U. Rannick, Auteur ; P. Aalto, Auteur ; P. Keronen, Auteur ; M. Kulmala, Auteur ; T. Vesala, Auteur Année de publication : 2003 Importance : p.4544-3510 Langues : Français (fre) Résumé : Aerosol particle fluxes were measured above a Scots pine forest in southern Finland by the eddy covariance (EC) technique. Condensational particle counter (CPC) was used in the EC system to detect the total particle number concentration in the size interval from about 10 nm to 500 nm. Turbulent records of velocity components and concentrations as well as fluxes were analysed for non-stationary behaviour by using quality tests. Aerosol particle concentration revealed often non-stationary behaviour, more frequently than other scalars like temperature, water vapour and carbon dioxide. During stationary episodes most of the flux estimates indicated deposition of particles into forest. Size-dependent deposition velocities were estimated by using auxiliary measurements of particle size distribution. A semi-empirical deposition model explained most of the variance observed in particle fluxes when size spectrum was dominated by below 100 nm particles. However, deposition velocity estimates for above 100 nm particles remained very uncertain.
in Journal of geophysical research
Journal of geophysical research, Vol.108 No.D17. Interpretation of aerosol particle fluxes over a pine forest: Dry deposition and random errors [articles et extraits] / U. Rannick, Auteur ; P. Aalto, Auteur ; P. Keronen, Auteur ; M. Kulmala, Auteur ; T. Vesala, Auteur . - 2003 . - p.4544-3510.
Langues : Français (fre)
Résumé : Aerosol particle fluxes were measured above a Scots pine forest in southern Finland by the eddy covariance (EC) technique. Condensational particle counter (CPC) was used in the EC system to detect the total particle number concentration in the size interval from about 10 nm to 500 nm. Turbulent records of velocity components and concentrations as well as fluxes were analysed for non-stationary behaviour by using quality tests. Aerosol particle concentration revealed often non-stationary behaviour, more frequently than other scalars like temperature, water vapour and carbon dioxide. During stationary episodes most of the flux estimates indicated deposition of particles into forest. Size-dependent deposition velocities were estimated by using auxiliary measurements of particle size distribution. A semi-empirical deposition model explained most of the variance observed in particle fluxes when size spectrum was dominated by below 100 nm particles. However, deposition velocity estimates for above 100 nm particles remained very uncertain.
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Code-barres Cote Support Localisation Section Disponibilité ART-9559-0 ART Document imprimé Bureau chercheur Bureau de AMIELH Muriel Disponible Documents numériques
http://dx.doi.org/10.1029/2003JD003542URL Journal of geophysical research, Vol.106 No.A11. Magnetized or unmagnetized: Ambiguity persists following Galileo’s encounters with Io in 1999 and 2000 / M. G. Kivelson
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol.106 No.A11 Titre : Magnetized or unmagnetized: Ambiguity persists following Galileo’s encounters with Io in 1999 and 2000 Type de document : articles et extraits Auteurs : M. G. Kivelson, Auteur ; S. P. Joy, Auteur ; K. K. Khurana, Auteur ; J. A. Linker, Auteur ; C. T. Russell, Auteur ; M. Volwerk, Auteur ; R. J. Walker, Auteur ; C. Zimmer, Auteur Année de publication : 2001 Importance : p.26121-26136 Langues : Français (fre) Résumé : Magnetometer data from Galileo’s close encounters with Io on October 11, 1999, and February 22, 2000, do not establish clearly either the existence or absence of an internal magnetic moment because they were acquired in regions where plasma currents contribute large magnetic perturbations. Data from an additional encounter on November 26, 1999, with closest approach beneath Io’s south polar regions, were lost. The recent passes add to our understanding of the interaction of the torus with Io and its flux tube and tighten the limits on possible internal sources of magnetic fields. Simple field-draping arguments account for some aspects of the observed rotations. Interpretations in terms of both a magnetized and an unmagnetized Io are considered. Data from the February 2000 pass (closest approach altitude 201 km, latitude 18°) rule out a strongly magnetized Io (surface equatorial field larger than the background field) but do not rule out a weakly magnetized Io (surface equatorial field of the order of Ganymede’s but smaller than the background field at Io). Models suggest that if Io is magnetized, its magnetic moment is not strictly antialigned with the rotation axis. The inferred tilt is consistent with contributions from an inductive field analogous to that observed at Europa and Callisto. If an induced field is present, the currents would flow in the outer mantle or aesthenosphere. Wave perturbations differ on flux tubes that do or do not link directly to Io and its ionosphere suggesting that the latter flux tubes are virtually stagnant in Io’s frame and that a unipolar inductor appropriately models the currents linking Io to Jupiter’s ionosphere.
in Journal of geophysical research
Journal of geophysical research, Vol.106 No.A11. Magnetized or unmagnetized: Ambiguity persists following Galileo’s encounters with Io in 1999 and 2000 [articles et extraits] / M. G. Kivelson, Auteur ; S. P. Joy, Auteur ; K. K. Khurana, Auteur ; J. A. Linker, Auteur ; C. T. Russell, Auteur ; M. Volwerk, Auteur ; R. J. Walker, Auteur ; C. Zimmer, Auteur . - 2001 . - p.26121-26136.
Langues : Français (fre)
Résumé : Magnetometer data from Galileo’s close encounters with Io on October 11, 1999, and February 22, 2000, do not establish clearly either the existence or absence of an internal magnetic moment because they were acquired in regions where plasma currents contribute large magnetic perturbations. Data from an additional encounter on November 26, 1999, with closest approach beneath Io’s south polar regions, were lost. The recent passes add to our understanding of the interaction of the torus with Io and its flux tube and tighten the limits on possible internal sources of magnetic fields. Simple field-draping arguments account for some aspects of the observed rotations. Interpretations in terms of both a magnetized and an unmagnetized Io are considered. Data from the February 2000 pass (closest approach altitude 201 km, latitude 18°) rule out a strongly magnetized Io (surface equatorial field larger than the background field) but do not rule out a weakly magnetized Io (surface equatorial field of the order of Ganymede’s but smaller than the background field at Io). Models suggest that if Io is magnetized, its magnetic moment is not strictly antialigned with the rotation axis. The inferred tilt is consistent with contributions from an inductive field analogous to that observed at Europa and Callisto. If an induced field is present, the currents would flow in the outer mantle or aesthenosphere. Wave perturbations differ on flux tubes that do or do not link directly to Io and its ionosphere suggesting that the latter flux tubes are virtually stagnant in Io’s frame and that a unipolar inductor appropriately models the currents linking Io to Jupiter’s ionosphere.
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Code-barres Cote Support Localisation Section Disponibilité ART-9636-0 ART Document imprimé Bureau chercheur Bureau de LE BARS Michael Disponible Journal of geophysical research, vol. 111 , n° C6. Spaceborne observations of ocean glint reflectance and modeling of wave slope distributions / F. M. Breon
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Titre de série : Journal of geophysical research, vol. 111 , n° C6 Titre : Spaceborne observations of ocean glint reflectance and modeling of wave slope distributions Type de document : articles et extraits Auteurs : F. M. Breon, Auteur ; N. Henriot, Auteur Année de publication : 2006 Importance : C06005.1-C06005.10 (25 ref.) Langues : Anglais (eng)
in Journal of geophysical research
Journal of geophysical research, vol. 111 , n° C6. Spaceborne observations of ocean glint reflectance and modeling of wave slope distributions [articles et extraits] / F. M. Breon, Auteur ; N. Henriot, Auteur . - 2006 . - C06005.1-C06005.10 (25 ref.).
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Code-barres Cote Support Localisation Section Disponibilité ART-2006C06 BRE Document imprimé Bureau chercheur Bureau de CAULLIEZ, Guillemette Disponible Journal of geophysical research, Vol. 111, No.C9. Radar scattering of the ocean surface and sea-roughness properties : A combined analysis from dual-polarizations airborne radar observations and models in C band / Alexis Mouche
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol. 111, No.C9 Titre : Radar scattering of the ocean surface and sea-roughness properties : A combined analysis from dual-polarizations airborne radar observations and models in C band Type de document : articles et extraits Auteurs : Alexis Mouche ; HAUSER D., Auteur ; V. Kudryavtsev, Auteur Année de publication : 2006 Importance : Art. C09004, 35 p. Langues : Anglais (eng) Mots-clés : radar cross-section sea surface anisotropy wave breaking. En ligne : http://www.ifremer.fr/docelec/notice/2006/notice1877.htm
in Journal of geophysical research
Journal of geophysical research, Vol. 111, No.C9. Radar scattering of the ocean surface and sea-roughness properties : A combined analysis from dual-polarizations airborne radar observations and models in C band [articles et extraits] / Alexis Mouche ; HAUSER D., Auteur ; V. Kudryavtsev, Auteur . - 2006 . - Art. C09004, 35 p.
Langues : Anglais (eng)
Mots-clés : radar cross-section sea surface anisotropy wave breaking. En ligne : http://www.ifremer.fr/docelec/notice/2006/notice1877.htm Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire Journal of geophysical research, Vol.111, No.C3. Drag coefficient reduction at very high wind speeds / John A. T. Bye
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Titre de série : Journal of geophysical research, Vol.111, No.C3 Titre : Drag coefficient reduction at very high wind speeds Type de document : articles et extraits Auteurs : John A. T. Bye, Auteur ; Alastair D. Jenkins, Auteur Année de publication : 2006 Importance : Art. C003114 Langues : Anglais (eng) Résumé : The correct representation of the 10-m drag coefficient for momentum (K10) at extreme wind speeds is very important for modeling the development of tropical depressions and may also be relevant to the understanding of other intense marine meteorological phenomena. We present a unified boundary layer model for (K10), which takes account of both the wave field and spray production, and asymptotes to the growing wind wave state in the absence of spray. The theoretical development is based on an air-sea system with shear layers in both fluids and contains three constants that must be determined empirically. This is done using data from observations, and the resulting behavior is interpreted in terms of spray. A feature of the results is the prediction of a broad maximum in K10. For a spray velocity of 9 m s-1, it is found that a maximum of K10 ~ 2.0 × 10-3 occurs for a 10-m wind speed, u10 ~ 40 m s-1, in agreement with recent GPS sonde data in tropical cyclones. Thus K10 is ‘‘capped’’ at its maximum value for all higher wind speeds expected. A physically based model, where spray droplets are injected horizontally into the airflow and maintained in suspension by air turbulence, gives qualitatively similar results. The effect of spray is also shown to flatten the sea surface by transferring energy to longer wavelengths.
in Journal of geophysical research
Journal of geophysical research, Vol.111, No.C3. Drag coefficient reduction at very high wind speeds [articles et extraits] / John A. T. Bye, Auteur ; Alastair D. Jenkins, Auteur . - 2006 . - Art. C003114.
Langues : Anglais (eng)
Résumé : The correct representation of the 10-m drag coefficient for momentum (K10) at extreme wind speeds is very important for modeling the development of tropical depressions and may also be relevant to the understanding of other intense marine meteorological phenomena. We present a unified boundary layer model for (K10), which takes account of both the wave field and spray production, and asymptotes to the growing wind wave state in the absence of spray. The theoretical development is based on an air-sea system with shear layers in both fluids and contains three constants that must be determined empirically. This is done using data from observations, and the resulting behavior is interpreted in terms of spray. A feature of the results is the prediction of a broad maximum in K10. For a spray velocity of 9 m s-1, it is found that a maximum of K10 ~ 2.0 × 10-3 occurs for a 10-m wind speed, u10 ~ 40 m s-1, in agreement with recent GPS sonde data in tropical cyclones. Thus K10 is ‘‘capped’’ at its maximum value for all higher wind speeds expected. A physically based model, where spray droplets are injected horizontally into the airflow and maintained in suspension by air turbulence, gives qualitatively similar results. The effect of spray is also shown to flatten the sea surface by transferring energy to longer wavelengths. Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire Journal of geophysical research, Vol. 93, n°C11. The Dependence of Sea Surface Slope on Atmospheric Stability and Swell Conditions / P. A. Hwang
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol. 93, n°C11 Titre : The Dependence of Sea Surface Slope on Atmospheric Stability and Swell Conditions Type de document : articles et extraits Auteurs : P. A. Hwang, Auteur ; Omar H. Shemdin, Auteur Année de publication : 1988 Importance : pp.13903–13912 Langues : Anglais (eng) Résumé : A tower-mounted optical device is used to measure the two orthogonal components of the sea surface slope. The results indicate that an unstable stratification at the air-sea interface tends to enhance the surface roughness. The presence of a long ocean swell system steers the primary direction of shortwave propagation away from wind direction, and may increase or reduce the mean square slope of the sea surface.
in Journal of geophysical research
Journal of geophysical research, Vol. 93, n°C11. The Dependence of Sea Surface Slope on Atmospheric Stability and Swell Conditions [articles et extraits] / P. A. Hwang, Auteur ; Omar H. Shemdin, Auteur . - 1988 . - pp.13903–13912.
Langues : Anglais (eng)
Résumé : A tower-mounted optical device is used to measure the two orthogonal components of the sea surface slope. The results indicate that an unstable stratification at the air-sea interface tends to enhance the surface roughness. The presence of a long ocean swell system steers the primary direction of shortwave propagation away from wind direction, and may increase or reduce the mean square slope of the sea surface. Réservation
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Code-barres Cote Support Localisation Section Disponibilité ART-1988903 HWA Document imprimé Bureau chercheur Bureau de CAULLIEZ, Guillemette Disponible Journal of geophysical research, Vol. 112, C10. Importance of the sea surface curvature to interpret the normalized radar cross section / Mouche, A. A., et al.
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol. 112, C10 Titre : Importance of the sea surface curvature to interpret the normalized radar cross section Type de document : articles et extraits Auteurs : Mouche, A. A., et al., Auteur Année de publication : 2007 Importance : C10002 Langues : Anglais (eng)
in Journal of geophysical research
Journal of geophysical research, Vol. 112, C10. Importance of the sea surface curvature to interpret the normalized radar cross section [articles et extraits] / Mouche, A. A., et al., Auteur . - 2007 . - C10002.
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Code-barres Cote Support Localisation Section Disponibilité ART-200710002 MOU Document imprimé Bureau chercheur Bureau de CAULLIEZ, Guillemette Disponible Journal of geophysical research, Vol. 112, C9. Sea surface slope statistics derived from Sun glint radiance measurements and their apparent dependence on sensor elevation / V. Ross
in Journal of geophysical research
Titre de série : Journal of geophysical research, Vol. 112, C9 Titre : Sea surface slope statistics derived from Sun glint radiance measurements and their apparent dependence on sensor elevation Type de document : articles et extraits Auteurs : V. Ross, Auteur ; D. Dion, Auteur Année de publication : 2007 Importance : C09015 Langues : Anglais (eng)
in Journal of geophysical research
Journal of geophysical research, Vol. 112, C9. Sea surface slope statistics derived from Sun glint radiance measurements and their apparent dependence on sensor elevation [articles et extraits] / V. Ross, Auteur ; D. Dion, Auteur . - 2007 . - C09015.
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Code-barres Cote Support Localisation Section Disponibilité ART-200709015 ROS Document imprimé Bureau chercheur Bureau de CAULLIEZ Guillemette Disponible