transport and dynamics of the current (the Subantarctic Flux and Dynamics Experiment, SAFDE;
Luther et al., 1997). The array spanned the SAF,
the main core of the ACC at this longitude, along
the line of WOCE repeat section SR3 (between
roughly 49 and 53°S in Fig. 4.6.3). Preliminary
analysis of the baroclinic (from the IESs) and
absolute (from the HEMs) transport time series
shows that while substantial barotropic flows
occur in some parts of the array at some times,
the 701-day mean baroclinic (relative to the
bottom) and absolute transports through the
central 200 km portion of the array are similar (54.4<3.1 Sv and 50.4<4.2 Sv, respectively)
(Luther et al., 1998).
Pairs of deep (1000 m) pressure gauges were
deployed across a number of passages to monitor
transport variability during WOCE. The idea,
based on ISOS experience, is that pressure difference across the passage is proportional to changes
in absolute transport. Meredith et al. (1996) found
that the variability of pressure difference measured
across Drake Passage for 4 years during WOCE
was somewhat smaller than measured during the
ISOS experiment (corresponding to a transport
standard deviation of 8 Sv in WOCE compared
with 10 Sv during ISOS). The greatest difference
between the two records was the absence during
WOCE of any events like two observed during
ISOS where transport changed by 40% in a few
SECTION 4 THE GLOBAL FLOW FIELD
278
EAC
SA F 10 5 ±7
5 ±5
22 ±2
PF
SF /S B 32 ±3
A S F 1 .5 ± 1
SA Z 22 ±8
TA S 8 ±1 3
1 3 0
o E
14 0
o E
150
o
E
16 0
o
E
1 7 0 o
E
7 0
o S
6 4
o S
5 6
o S
4 8
o S
4 0
o S
3 2
o S
3 0
o S
Fig. 4.6.5 Schematic summary of the main circulation features south of Tasmania, based on six repeats of WOCE
repeat line SR3.The numbers represent top-to-bottom transports (mean<1 standard deviation).TAS, ouflow of
Tasman Sea water; SAZ, anticyclonic recirculation in the Subantarctic Zone; SAF, Subantarctic Front; PF, two branches
of the Polar Front; SF/SB, southern front and southern boundary of the ACC; ASF, Antarctic Slope Front. See Rintoul
and Sokolov (2000) for details.
Luther et al., 1997). The array spanned the SAF,
the main core of the ACC at this longitude, along
the line of WOCE repeat section SR3 (between
roughly 49 and 53°S in Fig. 4.6.3). Preliminary
analysis of the baroclinic (from the IESs) and
absolute (from the HEMs) transport time series
shows that while substantial barotropic flows
occur in some parts of the array at some times,
the 701-day mean baroclinic (relative to the
bottom) and absolute transports through the
central 200 km portion of the array are similar (54.4<3.1 Sv and 50.4<4.2 Sv, respectively)
(Luther et al., 1998).
Pairs of deep (1000 m) pressure gauges were
deployed across a number of passages to monitor
transport variability during WOCE. The idea,
based on ISOS experience, is that pressure difference across the passage is proportional to changes
in absolute transport. Meredith et al. (1996) found
that the variability of pressure difference measured
across Drake Passage for 4 years during WOCE
was somewhat smaller than measured during the
ISOS experiment (corresponding to a transport
standard deviation of 8 Sv in WOCE compared
with 10 Sv during ISOS). The greatest difference
between the two records was the absence during
WOCE of any events like two observed during
ISOS where transport changed by 40% in a few
SECTION 4 THE GLOBAL FLOW FIELD
278
EAC
SA F 10 5 ±7
5 ±5
22 ±2
PF
SF /S B 32 ±3
A S F 1 .5 ± 1
SA Z 22 ±8
TA S 8 ±1 3
1 3 0
o E
14 0
o E
150
o
E
16 0
o
E
1 7 0 o
E
7 0
o S
6 4
o S
5 6
o S
4 8
o S
4 0
o S
3 2
o S
3 0
o S
Fig. 4.6.5 Schematic summary of the main circulation features south of Tasmania, based on six repeats of WOCE
repeat line SR3.The numbers represent top-to-bottom transports (mean<1 standard deviation).TAS, ouflow of
Tasman Sea water; SAZ, anticyclonic recirculation in the Subantarctic Zone; SAF, Subantarctic Front; PF, two branches
of the Polar Front; SF/SB, southern front and southern boundary of the ACC; ASF, Antarctic Slope Front. See Rintoul
and Sokolov (2000) for details.