Farmer Jesse Robert author Columbia University. Earth and Environmental Sciences Cronin Thomas M. author Vernal Anne de author Dwyer Gary S. author Keigwin Lloyd D. author Thunell Robert C. author Columbia University. Lamont-Doherty Earth Observatory originator text Articles 2011 English We reconstructed subsurface (∼200–400 m) ocean temperature and sea-ice cover in the Canada Basin, western Arctic Ocean from foraminiferal δ18O, ostracode Mg/Ca ratios, and dinocyst assemblages from two sediment core records covering the last 8000 years. Results show mean temperature varied from −1 to 0.5°C and −0.5 to 1.5°C at 203 and 369 m water depths, respectively. Centennial-scale warm periods in subsurface temperature records correspond to reductions in summer sea-ice cover inferred from dinocyst assemblages around 6.5 ka, 3.5 ka, 1.8 ka and during the 15th century Common Era. These changes may reflect centennial changes in the temperature and/or strength of inflowing Atlantic Layer water originating in the eastern Arctic Ocean. By comparison, the 0.5 to 0.7°C warm temperature anomaly identified in oceanographic records from the Atlantic Layer of the Canada Basin exceeded reconstructed Atlantic Layer temperatures for the last 1200 years by about 0.5°C. Paleoclimate science 38 L24602 1 6 2011 http://dx.doi.org/10.1029/2011GL049714 http://hdl.handle.net/10022/AC:P:14401 NNC NNC 2012-08-15 14:41:53 -0400 2012-08-15 14:54:51 -0400 8421 eng