Sökning: "last deglaciation"

Visar resultat 1 - 5 av 25 avhandlingar innehållade orden last deglaciation.

  1. 1. Northern Permafrost Region Soil Carbon Dynamics since the Last Glacial Maximum : a terrestrial component in the glacial to interglacial carbon cycle

    Författare :Amelie Lindgren; Gustaf Hugelius; Peter Kuhry; Fortunat Joos; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Soil organic carbon; Permafrost; Peat; Loess; Vegetation; Biome reconstruction; Last Glacial Maximum; Deglaciation; Glacial-interglacial cycle; Carbon cycle; naturgeografi; Physical Geography;

    Sammanfattning : At the Last Glacial Maximum (LGM), after ~100,000 years of relatively cold temperatures and progressively lower atmospheric carbon dioxide (CO2) concentrations, CO2 levels reached ~180 ppm, which is less than half of what we see today in a much warmer world (~400 ppm). Although much of this increase since the LGM is due to human-induced emissions, about 100 ppm of this increase can be attributed to natural variations seen over glacial to interglacial cycles. LÄS MER

  2. 2. Glaciodynamics, Deglacial Landforms and Isostatic Uplift during the last Deglaciation of Norrbotten, Sweden

    Författare :Mattias Lindén; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Sedimentologi; Sedimentology; Geologi; physical geography; Geology; glaciotectonic; thrust stacking; deforming bed; ribbed moraine; Niemisel moraine; De Geer moraine; isostatic uplift; glaciodynamics; deglaciation; klimatologi; kartografi; marklära; Fysisk geografi; geomorfologi; geomorphology; cartography; climatology; pedology;

    Sammanfattning : The aim of this thesis was to reconstruct the glaciodynamics, deglacial landforms, isostatic uplift and to date the deglaciation. Glaciodynamics and deglacial landforms were focused on to provide a process and depositional model for De Geer moraine and Niemisel moraine and to reveal their internal and spatial relationship, based on detailed sedimentological and structural investigations. LÄS MER

  3. 3. Marginal behaviour of the last Scandinavian Ice Sheet during its final termination and deglaciation over Northeastern Germany

    Författare :Joachim Albrecht; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Fysisk geografi; geomorfologi; climatology; cartography; pedology; geomorphology; Physical geography; Marginal dome; Deglaciation; Clast lithology; Clast fabric; Germany; Pomeranian; Weichselian; Lithostratigraphy; marklära; kartografi; klimatologi; Sedimentology; Sedimentologi;

    Sammanfattning : This thesis presents results from studies on geomorphology, lithostratigraphy and ice flow patterns during the final termination and deglaciation of the last Scandinavian Ice Sheet in NE Germany. Ice flow patterns derived from till fabrics and glaciotectonical data indicate that short-lived marginal domes had formed during the advance and the retreat of the last Scandinavian Ice Sheet in NE Germany. LÄS MER

  4. 4. In the wake of deglaciation - sedimentary signatures of ice-sheet decay and sea-level change : Studies from south-central Sweden and the western Arctic Ocean

    Författare :Henrik Swärd; Matt O'Regan; Martin Jakobsson; Juha Pekka Lunkka; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; paleoenvironmental changes; last deglaciation; sedimentology; Lake Vättern; western Arctic Ocean; Mackenzie Trough; Herald Canyon; maringeologi; Marine Geology;

    Sammanfattning : Lacustrine and marine sedimentary archives help unravel details concerning the withdrawal of large ice sheets and resulting sea-level changes during the last deglaciation (22 -11 kyr). In a series of four manuscripts, this PhD thesis investigates the sedimentological signatures from deglacial processes at three key locations in the northern hemisphere: (i) Lake Vättern (LV) in south-central Sweden, (ii) Herald Canyon (HC) in the western Chukchi Sea, and (iii) Mackenzie Trough (MT) on the westernmost edge of the Canadian Beaufort Shelf. LÄS MER

  5. 5. Weichselian glaciations in the middle Notec River region, northwest Poland

    Författare :Gert Pettersson; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Quaternary Geology; Kvartärgeologi; Geology; Geologi; Vistulian; Weichselian; Lithostratigraphy; Poland; Chodziez; Clast lithology; Clast fabrics; Deglaciation; Ice stream; Sedimentology; Sedimentologi; geomorphology; klimatologi; geomorfologi; climatology;

    Sammanfattning : This thesis presents results of studies on the ice flow pattern and ice movement mechanism during the Weichselian glaciations in the middle Notec River area, NW Poland. A new lithostratigraphy of the study area has been established, based on correlation of stratigraphical position, clast lithology, fabrics and grain size composition of till units. LÄS MER