HR: 16:00h
AN: OS34A-01    [Abstracts]
TI: The Subpolar Gyre - a regulator for the inflow of Atlantic water to the Nordic Seas
AU: * Hatun, H
EM: hjalmarh@frs.fo
AF: Faroese Fisheries Laboratory, Noatun 1, Torshavn, FO-110 Faroe Islands
AU: Sandoe, A
EM: annebrit@nersc.no
AF: Nansen Environmental and Remote Sensing Centre, Edvard Griegsvei 3A, Bergen, 5059 Norway
AU: Drange, H
EM: helge@nersc.no
AF: Nansen Environmental and Remote Sensing Centre, Edvard Griegsvei 3A, Bergen, 5059 Norway
AU: Drange, H
EM: helge@nersc.no
AF: Geophysical Institute, University of Bergen, Allegaten 70, Bergen, 5007 Norway
AU: Drange, H
EM: helge@nersc.no
AF: Bjerknes Centre for Climate Research, Allegaten 55, Bergen, 5007 Norway
AU: Drange, H
EM: helge@nersc.no
AF: Nansen-Zhu International Research Centre, ChaoYang district, Beijing, 100029 China
AU: Bentsen, M
EM: mats.bentsen@nersc.no
AF: Nansen Environmental and Remote Sensing Centre, Edvard Griegsvei 3A, Bergen, 5059 Norway
AU: Bentsen, M
EM: mats.bentsen@nersc.no
AF: Bjerknes Centre for Climate Research, Allegaten 55, Bergen, 5007 Norway
AB: As shown by Hakkinen & Rhines (2004), the sea level within the Subpolar Gyre, as determined by altimetry, has been increasing throughout the nineties and in the beginning of 21st century. This has resulted in a weakened baroclinic rim-current around the Gyre during this period. Here we show that the prominent increase in temperature and salinity in the Northeastern North Atlantic during the last decade is linked to the weakened Gyre conditions. In order to further explore the nature of the decadal scale variations of hydrography and volume transports of the pole-ward flowing Atlantic water crossing the Iceland-Scotland Ridge a numerical model is invoked. A 53 years hind-cast simulation with a regional version of the Nansen Center version of the Miami Isopycnic Coordinate Ocean Model (MICOM) indicates large variations in volume transport of Atlantic water through the Iceland-Faroe (IF) Gap. The mid 60s, the late 70s to the early 80s showed very weak transports while the periods 1971-1975 and 1989-1994 were characterized by abnormally strong transports. Strong/weak transport periods through IF Gap are concurrent with strong/weak deep convection periods in the Labrador Sea and an expanded/contracted Subpolar Gyre. The simulated transport through the IF Gap follows the temporal evolution of the sea level within the Subpolar Gyre.
DE: 4215 Climate and interannual variability (3309)
DE: 4255 Numerical modeling
DE: 4528 Fronts and jets
DE: 4536 Hydrography
DE: 4556 Sea level variations
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting