The goal of this multi-investigator, collaborative project is to evaluate and characterize sea ice and hydrographic conditions during periods of warm, low ice conditions in the central Arctic based on a multi-proxy investigation of Quaternary sediment cores recovered during the Healy-Oden Trans-Arctic Expedition?05 (HOTRAX?05). Paleobiological, chemical and sedimentological proxies (micro-fossil composition, stable isotopes, minor/trace elements, Nd isotopes etc), and ice-rafted debris provenance such as Fe-oxide grain fingerprinting will be used. An age model will be constrained by several independent chronostratigraphic techniques (14C, amino-acid racemization, magneto- and biostratigraphy), and correlation with reliable Quaternary stratigraphy, primarily ACEX and LOMROG cores. Results will provide (1) the first Arctic-wide evaluation of the effects of past warm conditions on the Arctic Ocean system and the long-term (ca. 150 kyr) context for climate change in the Arctic, and (2) significant improvements in much-needed boundary conditions for Arctic climate modeling and prediction of the future state of the Arctic Ocean. The Broader Impacts include (1) the participation of one post-doc?, three graduate students and several undergraduate students, (2) presentation of results at conferences and publication of papers, (3) a Web site that will include 3-D visualizations, (4) K-12 teacher and student outreach, (5) multi-investigator, international collaboration, and (6) a contribution to the paleoclimate component of SEARCH, the Study of Environmental Arctic Change.
