HR: 09:00h
AN: PP11A-05    [Abstracts]
TI: Holocene variations of sea-ice cover and sea-surface temperature in the western Arctic, from the Fram Strait to the Chukchi Sea
AU: * de Vernal, A
EM: devernal.anne@uqam.ca
AF: GEOTOP, UQAM, P.O. box 8888, Montréal, Qc H3C 3P8, Canada
AU: Hillaire-Marcel, C
EM: chm@uqam.ca
AF: GEOTOP, UQAM, P.O. box 8888, Montréal, Qc H3C 3P8, Canada
AU: Rochon, A
EM: andre_rochon@uqar.ca
AF: GEOTOP, UQAR, ISMER, Rimouski, Qc G5L 3A1, Canada
AU: Radi, T
EM: radi.taoufik@courrier.uqam.ca
AF: GEOTOP, UQAM, P.O. box 8888, Montréal, Qc H3C 3P8, Canada
AU: Ledu, D
EM: david_ledu@uqar.ca
AF: GEOTOP, UQAR, ISMER, Rimouski, Qc G5L 3A1, Canada
AU: Bonnet, S
EM: bonnet.sophie@courrier.uqam.ca
AF: GEOTOP, UQAM, P.O. box 8888, Montréal, Qc H3C 3P8, Canada
AB: The Northern Hemisphere sea ice record of the last decades shows large amplitude changes, which can be associated to the global warming. However, the anomalies also show regional patterns, which illustrate the importance of atmosphere and ocean dynamics in the distribution of sea ice. Beyond satellite observations, proxy data such as those provided by dinocyst assemblages permit to extent the record of sea ice back in time. Sea ice reconstructions spanning the last millennia are now available at several sites of the Arctic Ocean and subarctic seas (Fram Strait, Baffin Bay, Canadian Arctic Archipelago channels, Beaufort Sea and Chukchi Sea). The data illustrate large amplitude temporal trends but more importantly, opposite trends between the eastern and western Arctic. In particular, the results show a clear mid-Holocene to recent cooling accompanied with sea ice increase in the northern Baffin Bay and eastern Fram Strait. This contrasts with the changes recorded in the western part of the Canadian Arctic and Chukchi Sea, where a warming trend towards the late Holocene is accompanied with a decrease in the sea ice cover. In addition, when suitable resolution is achieved, the results indicate large amplitude centennial to millennial scale oscillations of sea-surface conditions and sea- ice cover, pointing to complex atmosphere/ocean interactions, at regional scale, in the Arctic.
DE: 1635 Oceans (1616, 3305, 4215, 4513)
DE: 3030 Micropaleontology (0459, 4944)
DE: 4540 Ice mechanics and air/sea/ice exchange processes (0700, 0750, 0752, 0754)
DE: 4944 Micropaleontology (0459, 3030)
DE: 4954 Sea surface temperature
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2009 Joint Assembly