HR: 0800h
AN: U31C-0500    [Abstracts]
TI: The First IPY Russia-US expedition in the Siberian Arctic seas: March-April 2007.
AU: Sergienko, V I
EM: sergienko@hq.febras.ru
AF: Headquarters, Far eastern Branch, Russian Academy of Sciences (FEBRAS), 50 Svetlanskaya Street, Vladivostok, 690950, Russian Federation
AU: * Semiletov, I P
EM: igorsm@iarc.uaf.edu
AF: International Arctic Research Center, University Alaska Fairbanks, 930 Koyukuk Drive (Akasofu building), Fairbanks, AK 99775, United States
AU: * Semiletov, I P
EM: igorsm@iarc.uaf.edu
AF: VI Il'ichov Pacific Oceanological Institute, 43 Baltic Street, Vladivostok, 690041, Russian Federation
AU: Shakhova, N E
EM: nshakhov@iarc.uaf.edu
AF: International Arctic Research Center, University Alaska Fairbanks, 930 Koyukuk Drive (Akasofu building), Fairbanks, AK 99775, United States
AU: Shakhova, N E
EM: nshakhov@iarc.uaf.edu
AF: VI Il'ichov Pacific Oceanological Institute, 43 Baltic Street, Vladivostok, 690041, Russian Federation
AU: Dudarev, O V
EM: dudarev@poi.dvo.ru
AF: VI Il'ichov Pacific Oceanological Institute, 43 Baltic Street, Vladivostok, 690041, Russian Federation
AU: Kosmach, D
AF: VI Il'ichov Pacific Oceanological Institute, 43 Baltic Street, Vladivostok, 690041, Russian Federation
AU: Charkin, A
AF: VI Il'ichov Pacific Oceanological Institute, 43 Baltic Street, Vladivostok, 690041, Russian Federation
AU: Spivak, E
AF: VI Il'ichov Pacific Oceanological Institute, 43 Baltic Street, Vladivostok, 690041, Russian Federation
AB: One of the key question of polar biogeochemistry is how the flux of carbon and nutrients would be altered by the long-range, inter-annual, and intra-seasonal variability in the atmosphere-land-shelf system in the Arctic. In order to address this question, the present conditions and the processes that govern the near-shore processes in the East Siberian Arctic need to be investigated using field studies with modern techniques and collection of historical data which are quite limited especially in winter. Most wide and shallow continental shelve in the Arctic Ocean and even in the whole World Ocean is the East-Siberian Shelf (ESS). We already established a joint US- Russia long-term study of complex summertime biogeochemical studies in the atmosphere-land-shelf system in the ESS: since 2003 we have accomplished Five joint Russia-USA summertime expeditions with focus in the nearshore zone of the south-eastern part of the Laptev Sea and adjacent part of the East-Siberian Sea which is the area most impacted by ongoing changes. However, this area is still remained largely understudied and provides an excellent natural laboratory to make progress on an improved understanding of the interactions across atmosphere-land-ocean system and their impacts on freshwater dynamics and biogeochemistry. To answer some of these questions (seasonal variability in methane and carbon dioxide release, offshore export of terrestrial organic carbon, sedimentation) the First IPY Russia-US expedition was conducted over the Laptev Sea shelf. A tractor sledge caravan started from Tiksi, Russia on March 30th. April 1st-April 15th was spent in the south- eastern part of the Laptev Sea eastward of the Lena River delta where 53 complex oceanographic stations (CTD/water/sediment sampling) were done through 2m fast ice along the ~1,700km route. Methane measurements, gas extraction, pH and filtering samples were also processed in a mobile laboratory. Extremely high concentrations of methane (up to 5 micromole which is two orders of magnitude higher compared to summer concentrations) were measured. Comparing the data already obtained in the same area using the same techniques during summertime we studied robust inter-seasonal variability of major physical and hydro- chemical environmental parameters.
DE: 0428 Carbon cycling (4806)
DE: 0490 Trace gases
DE: 3022 Marine sediments: processes and transport
DE: 4207 Arctic and Antarctic oceanography (9310, 9315)
DE: 4217 Coastal processes
SC: Union [U]
MN: 2007 Fall Meeting