Reconstructing palaeoclimate from southern Poland using stalagmites from Niedźwiedzia Cave coupled with modern day environmental monitoring data

Abstract

Abstract

The aim of this thesis is to perform a palaeoclimate reconstruction for Niedźwiedzia Cave, southern Poland using stable isotopes, and to examine factors which may influence these results. Stable isotope analyses of three stalagmite samples from Niedźwiedzia Cave yielded a palaeoclimate record for the last 16,000 years for this region. Uranium series dating provided a chronology that was used to investigate oxygen and carbon stable isotope variations through the record, which reveal the effects of some notable palaeoclimate events such as the Younger Dryas Event, the Bølling-Allerød and Bond Events. The identification of shorter, non-cyclic events (e.g. the 8.2 ka event) was hampered by large errors in the uranium series dating due to the low uranium content of the stalagmites from the site.
Oxygen isotopes in meteoric precipitation (δ18Op) were examined to determine the main controls that affect isotope ratios such as the temperature and continental effects. An investigation was also carried out to determine whether a relationship is observed between precipitation results and dominant European circulation patterns, i.e. the North Atlantic Oscillation (NAO) and the Quasi-Biennial Oscillation (QBO). Understanding these controls has wider implications for interpreting the palaeoclimate record, as recognizing how they alter the isotopic signature of a speleothem at the time of deposition can then be used to calibrate the record. The investigation was carried out by examining anomaly data from a multitude of datasets, including drip-water data from Niedźwiedzia Cave and Global Network of Isotopes in Precipitation (GNIP) data from multiple sites in Germany and Poland. Identification of anomalous data was accomplished by using linear regression analysis of δ18Op data. Back trajectory analyses were then carried out for these data points to determine the air mass’s source zone, and to provide further information on the factors which may have affected the δ18Op, such as the potential magnitude of the rainout effect, temperature effect and the amount effect.