Sökning: "polar wind"

Visar resultat 16 - 20 av 27 avhandlingar innehållade orden polar wind.

  1. 16. On Numerical Tracer Advection in the Stratosphere and Assimilation of Data from Satellites

    Författare :JOHN RÖSEVALL; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; stratosphere; transport modelling; O3; ozone depletion; data assimilation;

    Sammanfattning : Since the early 1980's, large scale ozone depletion has been observed in the lower regions of the ozone layer over Antarctica when sunlight returns to the polar region in the early spring. The destruction of ozone is attributed to anthropogenic emissions of freon and halon compounds that have augmented the natural stratospheric concentrations of nonreactive Clx and Brx reservoir species with several hundred percent. LÄS MER

  3. 17. Energy Transfer and Conversion in the Magnetosphere-Ionosphere System

    Författare :Lisa Rosenqvist; Stephan Buchert; Andris Vaivads; Mike Lockwood; Uppsala universitet; []
    Nyckelord :Space and plasma physics; solar system; space physics; magnetospheric physics; plasma physics; magnetic storms; substorms; boundary layers; magnetic reconnection; energy conversion; space weather; Rymd- och plasmafysik;

    Sammanfattning : Magnetized planets, such as Earth, are strongly influenced by the solar wind. The Sun is very dynamic, releasing varying amounts of energy, resulting in a fluctuating energy and momentum exchange between the solar wind and planetary magnetospheres. LÄS MER

  4. 18. On the Properties of Ionospheric Convection

    Författare :Torbjörn Sundberg; Lars Blomberg; Judy Cumnock; Mike Lockwood; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrophysics; Elektrofysik;

    Sammanfattning : The solar wind interaction with the magnetosphere-ionosphere system continuously drives plasma convection in the polar regions of the ionosphere. The flow velocity and the shape of the convection pattern are closely dependent on the interplanetary conditions, in particular the direction of the interplanetary magnetic field (IMF). LÄS MER

  5. 19. O+ outflow during geomagnetic storms observed by Cluster satellites

    Författare :Audrey Schillings; Hans Nilsson; Stephan Buchert; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Atmosfärsvetenskap; Atmospheric Science;

    Sammanfattning : The region of space dominated by the Sun's magnetic field is called the heliosphere. It envelops the entire solar system including Earth. Therefore, a strong coupling exists between the Sun and our planet. LÄS MER

  7. 20. Global Magnetospheric Plasma Convection

    Författare :Stefan Eriksson; KTH; []
    Nyckelord :Geophysics; satellite measurements; electric fields; magnetosphere; magnetic reconnection;

    Sammanfattning : This thesis deals with the global aspects of plasmaconvection in the magnetosphere as measured by the low-altitudepolar orbiting Astrid-2 and FAST satellites. The major focus ison the electric field measurements, but they are alsocomplemented by magnetic field, ion and electron particle data,which is fundamental for the understanding of theelectrodynamics of the high-latitude auroral ovals and polarcap, which are the regions analysed here. LÄS MER