Sökning: "climate reconstructions"

Visar resultat 1 - 5 av 50 avhandlingar innehållade orden climate reconstructions.

  1. 1. Holocene Climate in Central and Southern Sweden : Quantitative Reconstructions from Fossil Data

    Författare :Karin Antonsson; Keith Bennett; Heikki Seppä; Andy Lotter; Uppsala universitet; []
    Nyckelord :Quaternary geology; pollen analysis; climate reconstructions; transfer functions; vegetation dynamics; Sweden; Kvartärgeologi;

    Sammanfattning : In quantitative palaeoecology modern species-environmental relationships can be statistically modelled, and recent development has made the calibration models more statistically robust. These models are used to transform fossil assemblages to quantitative estimates of past environmental conditions. LÄS MER

  2. 2. Holocene environmental changes and climate variability in the Eastern Mediterranean : Multiproxy sediment records from the Peloponnese peninsula, SW Greece

    Författare :Christos Katrantsiotis; Stefan Wastegård; Rienk Smittenberg; Jan Risberg; Elin Norström; Sherilyn Fritz; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Mediterranean; Greece; Peloponnese; Holocene; sediments; diatoms; n-alkanes; stable isotopes; tectonics; climate variability; monsoons; NAO; NCP; naturgeografi; Physical Geography;

    Sammanfattning : This thesis presents multiproxy reconstructions of the mid to late Holocene climate and environmental changes in the Peloponnese peninsula, SW Greece. The combined dataset consists of diatom, biomarker and X-ray fluorescence spectrometry (XRF) elemental data in radiocarbon-dated sediment cores taken from the Agios Floros fen and the Gialova Lagoon in SW Peloponnese and the Ancient Lake Lerna in NE Peloponnese. LÄS MER

  3. 3. 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; 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

  4. 4. Intramolecular isotope analysis reveals plant ecophysiological signals covering multiple timescales

    Författare :Thomas Wieloch; Jürgen Schleucher; Mats Nilsson; Gerd Gleixner; Lisa Wingate; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; NATURAL SCIENCES; NMR spectroscopy; tree ring; isotope ratio; isotope effect; intramolecular 13C 12C signal; carbon allocation; acclimation; plant performance; climate reconstruction; plant ecophysiology;

    Sammanfattning : Our societies' wellbeing relies on stable and healthy environments. However, our current lifestyles, growth-oriented economic policies and the population explosion are leading to potentially catastrophic degradation of ecosystems and progressive disruption of food chains. LÄS MER

  5. 5. Modelling the early to mid-Holocene Arctic climate

    Författare :Marit Berger; Arne Johansson; Rodrigo Caballero; KTH; []
    Nyckelord :Arctic; early Holocene; mid-Holocene; climate modelling; paleoclimate; sea ice; climate change;

    Sammanfattning : In the recent past it has become evident that the Earth's climate is changing, and that human activity play a significant role in these changes. One of the regions where the ongoing climate change has been most evident is in the Arctic: the surface temperature has increased twice as much in this region as compared to the global average, in addition, a significant decline in the Arctic sea-ice extent has been observed in the past decades. LÄS MER