Sökning: "northern Fennoscandia"

Visar resultat 1 - 5 av 33 avhandlingar innehållade orden northern Fennoscandia.

  1. 1. Holocene climate and atmospheric circulation changes in northern Fennoscandia : Interpretations from lacustrine oxygen isotope records

    Författare :Christina E. Jonsson; Gunhild Rosqvist; Jan Seibert; Philip Barker; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; oxygen isotope; diatom silica; lake sediment; atmospheric circulation; North Atlantic Oscillation; northern Fennoscandia; The Holocene; Little Ice Age; Physical geography; Naturgeografi; Physical Geography; naturgeografi;

    Sammanfattning : This thesis investigates how variations in the oxygen isotopic composition of lake waters in northern Fennoscandia are recorded in lake sediment archives, especially diatoms, and how these variations can be used to infer past changes in climate and atmospheric circulation. Results from analyses of the oxygen isotopic composition of lake water samples (δ18Olakew) collected between 2001 and 2006 show that δ18O of northern Fennoscandian lakes is mainly controlled by the isotopic composition of the precipitation (δ18Op). LÄS MER

  2. 2. The Eemian Interglacial at Sokli, northern Finland : A multi-proxy environmental and climatic reconstruction based on a 9 m long lacustrine sediment sequence

    Författare :Anna Plikk; Karin F. Helmens; Oliver Heiri; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Last Interglacial MIS5e ; northern Europe; palaeolimnology; palaeoecology; temperature reconstruction; multiple proxies; climate dynamics; climatic events; kvartärgeologi; Quaternary Geology;

    Sammanfattning : Understanding the fundamentals of the Earth’s climate system during the Quaternary Period (the past ca 2.6 million years) is of imminent interest in light of the reported recent climatic changes. LÄS MER

  3. 3. Berggrundsmorfologiska studier över kustslätten och Norrlandsterrängen inom delar av Umeå kommun, norra Norrland

    Författare :Karel Miškovský; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Precambrian bedrock; Fennoscandia; morphology; Umeå; weathering processes;

    Sammanfattning : The aim of this studv is to investigate interrelationships betweenbedrock relief and geological material. The area of investigation covers ca 350 km and is located in the Precambrian bedrock in the central part of Umeå commune, in northern Norrland. LÄS MER

  4. 4. Geography and geometry of pre-Caledonian western Baltica: U-Pb geochronology and Palaeomagnetism

    Författare :Emma Rehnström; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical geography; geomorphology; pedology; cartography; climatology; Fysisk geografi; geomorfologi; marklära; kartografi; klimatologi; Fennoscandia; correlations; Baltica; Early Palaeozoikum; palaeogeography; orthogneisses; nappes; palaeomagnetism; U-Pb geochronology; Caledonian orogen; Scandinavia;

    Sammanfattning : In an attempt to reconstruct the pre-Caledonian cratonic margin of Fennoscandia, U-Pb geochronological and geochemical investigations have been performed on allochthonous orthogneisses in the northern Swedish Caledonides. The crystalline basement of the nappes have also been examined to further constrain the continuation of various chronologically defined orogenic belts. LÄS MER

  5. 5. Tree Rings as Sensitive Proxies of Past Climate Change

    Författare :Håkan Grudd; Wibjörn Karlén; Brian Luckman; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Tree ring; width; density; climate; temperature; change; variability; sensitivity; Torneträsk; Tornetrask; Sweden; Fennoscandia; explosive; volcanic; eruption; Santorini; Thera; subfossil; Fitzroya; Chile; Physical geography; Naturgeografi;

    Sammanfattning : In the boreal forests of the Northern Hemisphere, time series of tree-ring width (TRW) and maximum density in the latewood (MXD) are highly correlated to local instrumental summer-temperature data and are thus widely used as proxies in high-resolution climate reconstructions. Hence, much of our present knowledge about climatic variability in the last millennium is based on tree-rings. LÄS MER