Sökning: "space weather"

Visar resultat 6 - 10 av 68 avhandlingar innehållade orden space weather.

  1. 6. 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

  2. 7. Theoretical Atomic Spectroscopy of Earthbound and Stellar Plasma

    Författare :Jon Grumer; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; atomstruktur; atomära processer; elektronkorrelation; plasmaspektroskopi; magnetfält; hyperfinstruktur; solkoronan; rymdväder; förekomst av grundämnen i stjärnor; datorsimuleringar; Zeemaneffekt; relativistiska effekter; atomic structure; atomic processes; computer simulation; electron correlation; relativistic atomic theory; plasma spectroscopy; Zeeman effect; magnetic fields; hyperfine structure; solar corona; space weather; stellar abundances; Fysicumarkivet A:2016:Grumer;

    Sammanfattning : Motivated by spectroscopic analysis of astrophysical and laboratory plasma, this thesis concerns the fundamental structure and spectral properties of atoms and their ions. The multiconfiguration Dirac-Hartree-Fock (MCDHF) method is used to predict the emission or absorption of radiation, by atomic systems in general, and of heavy and highly charged ions in particular. LÄS MER

  3. 8. Space Weather - Solar magnetic variation and its impact on Earth's atmosphere

    Författare :Fredrik Boberg; Astronomi - Genomgår omorganisation; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; klimatologi; kartografi; pedology; Physical geography; marklära; geomorphology; climatology; cartography; space weather - solar magnetism - solar wind - geomagnetic activity- North Atlantic Oscillation - climate change - neural networks- wavelet analysis; Fysisk geografi; geomorfologi; Astronomy; space research; cosmic chemistry; Astronomi; rymdvetenskap; kosmisk kemi; Fysicumarkivet A:2003:Boberg;

    Sammanfattning : A solar magnetic field is continuously being created in the solar interior. As the field evolves outward through the solar atmosphere and into the enveloping heliosphere, it causes effects on a wide range of temporal and spatial scales. LÄS MER

  4. 9. Solar Wind and Geomagnetic Activity - Predictions Using Neural Networks

    Författare :Hans Gleisner; Astronomi - Genomgår omorganisation; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geophysics; kosmisk kemi; rymdvetenskap; magnetosphere; solar wind; space weather; geomagnetic activity; geomagnetism; ring current; auroral electrojet; neural networks; forecasting; Astronomy; space research; Astronomi; cosmic chemistry; physical oceanography; meteorology; Geofysik; fysisk oceanografi; meteorologi; Fysicumarkivet A:2000:Gleisner;

    Sammanfattning : This thesis shows how artificial neural networks (ANNs) can be applied to predict geomagnetic activity from solar-wind data. It introduces and summarizes five papers where development of ANN models are reported, and where predictions of geomagnetic activity are discussed. LÄS MER

  5. 10. Understanding Weather effects on, in, and from large Herbivore Population Dynamics

    Författare :Lena Månsson; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; monitoring; management; data collection; Ecology; Ekologi; indirect effects; vegetation; modeling; time series analysis; precipitation; weather; population dynamics; Large herbivores;

    Sammanfattning : Large herbivores are monitored for various reasons in many areas around the world. Data from such monitoring can be of varying degree of detail and extent. Several studies have shown that we need extensive amounts of data with a high degree of detail to be able to understand anything from it. LÄS MER