HIGH-RESOLUTION LAKE SEDIMENT RECORDS OF HOLOCENE CLIMATE FROM MAINE, USA

In eastern North America, lakes located at ecotonal boundaries provide the most likely sites to register abrupt, small-magnitude Holocene climatic events. Reliable climate proxies, high-resolution sampling, and well-dated core sequences enable researchers to examine Holocene climatic records with improved confidence. Here we present, two independently AMS 14C-dated lake sediment records of Holocene climate from the White Mountains of Maine, USA. A loss-on-ignition analysis from each site is used to infer general trends of Holocene lake productivity. A paleotemperature reconstruction using chironomids (aquatic insects) has also been completed for the 8200 event. The sampling intensity (0.5 cm) of each site’s sediment record and 30 total 14C-dates yield a mean sample resolution of approximately 15 and 10 cal yrs for Speck Pond and Surplus Pond, respectively. The high-resolution nature of these records will provide the basis for statistical inferences regarding climate variability over the last ~11, 500 cal yrs BP. The preliminary data suggest a non-quiescent Holocene climate with marked variability. The chironomid temperature reconstructions of the 8200 event are less conclusive, with highly variable summer surface-water temperatures from Speck Pond and a “no-analogue” situation at Surplus Pond.