Forschungskolloquium PG: Assessing past and recent climate variability in mountainous regions using tree-ring parameters. – Mi. 02.07.2025
Physisch-geographisches Kolloquium (PG):
Assessing past and recent climate variability in mountainous regions using tree-ring parameters
Dr. Wolfgang Meier (Fachbereich Umwelt und Biodiversität, Abt. Geologie und Geographie, AG Klima- und Umweltdynamik, Paris Lodron Univ. Salzburg)
Moderation: Prof. Dr. Achim Bräuning
Stable oxygen isotopes (δ¹⁸O) derived from tree-ring cellulose provide a highly valuable proxy for reconstructing past climate conditions. The annually resolved isotopic composition reflects variations in temperature, precipitation, and source water, making it a powerful indicator of hydroclimatic changes over time. Studies on δ¹⁸O are crucial for understanding long- and short-term climate variability beyond the instrumental record or in remote regions where instrumental data are limited or absent.
This talk introduces the fundamental principles of isotope fractionation, tracing the pathway from the ocean (source) to tree-rings (sink), and highlights the suitability of δ¹⁸O as a hydroclimatic proxy across diverse climatic zones. In particular, the presentation features case studies from southernmost South America, dominated by westerly wind systems, and the monsoon-influenced Himalayan Arc.
New perspectives are presented that go beyond conventional climate-proxy relationships, which typically rely on monthly climate data. By integrating analyses of daily synoptic weather patterns combined with backward trajectory modeling, the research reveals that even short-lived weather events-lasting just a few days-can leave a distinct imprint on the annually resolved δ¹⁸O signal. For instance, in monsoonal Nepal, a surprising finding is that tree-ring δ¹⁸O is more strongly influenced by climatic conditions during monsoon break periods rather than during active monsoon phases. These novel insights have the potential to refine or challenge previous reconstructions of monsoon intensity and may offer explanations for inconsistencies in past climate reconstructions.
Wann: Mittwoch, 02.07.2025 von 12:30 bis 14:00 Uhr
Wo: Präsenz, Hörsaal C, Kochstraße 4, 91054 Erlangen.
Vortragsübersicht für das Institutskolloquium im Sommersemester 2025.
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Fragen zum Kolloquium?
Organisation: Dr. Julia Kieslinger (KG) und Dr. Sebastian Feick (PG)