HOLOCENE RECORD FROM THE ANTARCTIC PENINSULA: 200 TO 1800 YEAR OSCILLATIONS

A continuous, ultra-high resolution time series for the entire Holocene is now available based upon Ocean Drilling Program (Leg 178) cores and a suite of Jumbo Piston Cores collected from the Pacific and Weddell Sea side of the Antarctic Peninsula. Over 100 radiocarbon dates from these cores have produced records that reveal a complex paleooceanographic story. This record includes temporal oscillations in paleoenvironmental proxies at time scales of a few decades (~50 years), centuries (~200 and 400 years), and millenia (~1800 years). Following deglaciation of the inner shelf, about 13 ka BP, a prolonged Middle Holocene climatic optimum is recognized and is delineated by several peaks in preserved organic matter within an overall maximum in mass accumulation. Neoglacial cooling and reduced mass accumulation began around 3300 years BP, culminating in a well defined LIA event starting about 700 years BP. Within the neoglacial are very pronounced, 200-400 yr cycles as shown by several of the paleoenviornmental proxies. Regional correlation of these events is quite persistent suggesting a linkage with Southern Ocean phenomena and/or atmospheric teleconnections with the South Pacific. Regional advance and retreat of ice shelves is associated with the last neoglacial event (the LIA) and the last century of climate warming, respectively.

Many of these events are recognized as global in character and thus suggest a good linkage between the Antarctic Peninsula ocean/cryosphere system and the rest of the world during the Holocene epoch.