Orbital- and millennial-scale climate and vegetation changes between 32.5 and 6.9k cal a BP from Hanon Maar paleolake on Jeju Island, South Korea

摘要

Orbital- and millennial-scale climate and vegetation changes between 32.5 and 6.9k cal a BP from Hanon Maar paleolake on Jeju Island, Korea, were demonstrated by high-resolution multi-proxy data (pollen, magnetic susceptibility, total organic carbon, carbonitrogen ratios and sediment grain size). High-resolution pollen records provided detailed information on the vegetation response to climate change. The Thalictrum pollen percentage, which corresponded to the magnetic susceptibility data, and the first principal component of principalcomponent analysis of pollen data were good indicators of the orbital- and millennial-scale dry/wet cycle in the study area. Hanon pollen and magnetic susceptibility records suggested that colder and drier conditions were prevalent between 25.2 and 17.6k cal a BP in the study area due to a precession-induced decrease in summer insolation. Hanon multi-proxy data were correlated with oxygen isotope records from Greenland and Hulu cave, suggesting the possible teleconnection of millennial-scale climate oscillations between North Atlantic and East Asian regions. According to our results, Heinrich-like cold events probably occurred around 31.1, 25.2 and 16.7k cal a BP, and the warm intervals observed around 30.7 and 29.9k cal a BP may have corresponded to Dansgaard-Oeschger warm events 4 and 3, respectively.