Instrumental climate time-series at polar latitudes cover only the past few decades and thus miss a long-term perspective that is, however, crucial for distinguishing natural and anthropogenic triggers for climate change. The present interglacial period, the Holocene and the preceding termination of the last ice age, offer some of the most complete, best dated and highly-resolved marine sediment archives. Hence these archives yield the possibility to extend the short instrumental records back in time in order to better understand climate dynamics on time-scales most relevant for human societies. This forms the baseline for accurate future projections.
We study high resolution marine climate archives from selected strategic locations in the high latitudes at continental margins in order to document and better understand longer-term changes in decadal to centennial-scale coupled atmosphere-ocean changes and implications for climate modes known from the modern climate system.
In this context we investigate
- Hydrological changes in southern South America and implications for the Southern Westerlies
- Temperature variations from the Antarctic Peninsula across the Drake Passage to the South American mid-latitudes
- Regional dynamics and development of upper ocean temperature and stratification in the Subarctic North Pacific and its marginal seas.
A major effort is the development of a detailed stratigraphic framework in order to accurately link the different climate archives as a prerequisite for the analysis of sub-millennial-scale climate variability including e.g. leads and lags in the climate system.