Sökning: "geomagnetic reconstructions"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden geomagnetic reconstructions.

  1. 1. Disentangling production and climate signals from high-resolution Beryllium records: implications for solar and geomagnetic reconstructions

    Författare :Minjie Zheng; MERGE: ModElling the Regional and Global Earth system; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Solar Activity; 10Be; 7Be; ice cores; tropopause; climate; cosmogenic radionuclides; geomagnetic reconstructions; multi-linear regression;

    Sammanfattning : The sun is the most important energy source for the Earth’s climate system, however, influences of solar variations on climate are not fully understood. Studying past solar activity can improve our understanding of what role the sun plays in Earth’s climate. LÄS MER

  3. 2. Assessing Holocene and late Pleistocene geomagnetic dipole field variability

    Författare :Andreas Nilsson; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geomagnetic field; palaeomagnetism; the Holocene; dipole tilt; dipole moment; cosmogenic radionuclides;

    Sammanfattning : Palaeomagnetic studies of continuous geological archives and archaeological artefacts are required to reconstruct geomagnetic field changes beyond the range of historical observations. In this thesis I assess the reliability of sedimentary palaeomagnetic data and Holocene dipole field reconstructions. LÄS MER

  4. 3. Improving archaeomagnetic dating through new data acquisition and method development

    Författare :Megan Allington; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Archaeomagnetism; Palaeomagnetism; Geomagnetic field; Archaeomagnetic dating;

    Sammanfattning : The Earth’s magnetic field (or geomagnetic field) has been measured for hundreds of years, starting with maritime observations from logbooks for navigation purposes to present day real-time recording by satellites. From these records, the geomagnetic field variation throughout recent time is well-understood. LÄS MER

  5. 4. Testing palaeomagnetic and 14C based geochronological methods in the Baltic Sea

    Författare :Bryan Lougheed; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Baltic Sea; coastal; geochronology; palaeomagnetic secular variation; PSV; radiocarbon; 14C; reservoir age; R t ; ΔR; salinity; δ18O; geomagnetic field; Holocene; deglacial; Fennoscandia.;

    Sammanfattning : The Baltic Sea is a continental shelf sea that is influenced by both river runoff and marine water. The two water masses are vertically stratified in the Baltic Sea, resulting in a positive, estuarine circulation system, which has undergone changes in the past due to isostatic uplift of the Baltic basin. LÄS MER

  7. 5. Investigations of temporal changes in climate and the geomagnetic field via high-resolution radiocarbon dating

    Författare :Anette Mellström; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; wiggle-matching; Radiocarbon dating; 14C; 2800 cal BP; climate change; solar activity; palaeomagnetism; lake sediments; varves; post-depositional remanent magnetisation; PDRM; lock-in; peat deposits; Sweden;

    Sammanfattning : Geological archives have shown periods of abrupt climate change in the relatively stable Holocene epoch (last ca. 11 700 years). One of these periods was around 2800 cal BP. Several records, mainly from Europe, reveal a shift towards wetter, cooler and windier conditions. LÄS MER