Decadal fluctuations of the water mass properties in the Souther Ocean

• Main Authors: Fahrbach, Eberhard, Boebel, Olaf, Hoppema, Mario, Klatt, Olaf, Rohardt, Gerd, Wisotzki, Andreas
• Format: Conference Object
• Language: unknown
• Published: 2009
• Subjects: Southern Ocean; Weddell Sea
• Online Access: https://epic.awi.de/id/eprint/20788/; https://hdl.handle.net/10013/epic.33001

DECADAL FLUCTUATIONS OF THE WATER MASS PROPERTIES IN ATLANTIC SECTOR OF THE SOUTHERN OCEAN E. Fahrbach1, Olaf Boebel1, Mario Hoppema1, Olaf Klatt1, Gerd Rohardt1 and Andreas Wisotzki11Alfred-Wegener-Institut für Polar- und Meeresforschungin der Helmholtz-Gemeinschaft, Bremerhaven, Germany [[e-mail]] INTRODUCTIONThe Southern Ocean contributes through atmosphere-ice-ocean interaction processes to the variability of the global climate system (Rintoul et al, 2001). Atmosphere-ice-ocean interactions, occurring in the open ocean and on the shelves, lead to water mass conversions. Whereas the shelf processes affect a reservoir limited through the shallow water depth (Baines and Condie, 1998) and the cross frontal transports at the shelf edges, open ocean processes can affect deeper layers directly if the stability of the water column is weak. A major contribution to the global deep and bottom water formation occurs in the Weddell Sea (Carmack, 1977, Rintoul, 1998). It is controlled by the transport of source waters into the Weddell Sea, transformation processes within the Weddell Sea, and the transport of modified water out of the Weddell Sea (Gill, 1973). Figure 1 Schematic representations of the Weddell gyre circulation and the location of the transect displayed in figure 2 (dotted line). Red arrows indicate inflow and circulation of Warm Deep Water, light blue arrows sinking water masses at the continental slope. Dark blue arrows stand for deep and bottom water circulation and water masses leaving the basin. The green arrow indicates shelf water leaving the western Weddell Sea. In the Weddell Sea, Circumpolar Deep Water enters from the north and circulates as Warm Deep Water in intermediate layers within the large-scale cyclonic gyre (Figure 1). Heat and salt are transported from that water mass into the surface layer by means of upwelling and entrainment. The vertical transport of heat and salt compensates the heat loss and the fresh water gain at the sea surface. The delicate balance of buoyancy ...