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Tables

Table 1: Summary of published estimates of geostrophic quasi-meridional transports of Antarctic Intermediate Water in the South Atlantic: Mn = net transport across trans-oceanic sections; Mw = transport of the western boundary current; Mr = transport of a return current; Me = transport of the eastern boundary current. These transports were estimated by Fu (1981), Stramma and Peterson (1989, SP), Rintoul (1991), Zemba (1991), Peterson (1992) and Holfort (1994). The ``Oceanus 133'' sections were taken in 1983. The WOCE sections A9 and A10 are from 1991 and 1993, respectively. The sections of ``Thomas Washington Marathon, leg 9'' were taken from November to December 1984. IGY = International Geophysical Year (1957-1959).
Latitude Mn/Sv Mw/Sv Mr/Sv Me/Sv Data basis Method Source
8$^{\circ }S$ $\approx$5 $\approx$25 - $\approx$-15 IGY inverse model Fu
11$^{\circ }S$ 8 $\approx$17 - $\approx$4 Oceanus 133 inverse model Holfort
16$^{\circ }S$ $\approx$5 - -   IGY inverse model Fu
19$^{\circ }S$ 6.5 $\approx$9 - $\approx$3 WOCE A9 inverse model Holfort
23$^{\circ }S$ - - - 1.2 Oceanus 133 ref. $\sigma _0$=27.4 3 SP
23$^{\circ }S$ - - - 2.5 Oceanus 133 ref. $\sigma _0$=27.75 3 SP
23$^{\circ }S$ - - - 2.4 Oceanus 133 ref. bottom SP
23$^{\circ }S$ $\approx$5 $\approx$5 - $\approx$0 Oceanus 133 inverse model Holfort
24$^{\circ }S$ $\approx$5 $\approx$5 - $\approx$0 IGY inverse model Fu
24$^{\circ }S$ - - - 0.4 Crawford, 1958 ref. $\sigma _0$=27.75 3 SP
24$^{\circ }S$ - - - 0.0 Crawford, 1958 ref. bottom SP
27$^{\circ }S$ - 0.5 - - Marathon, leg 9 ref. $\sigma _0$=27.2 3 Zemba
27$^{\circ }S$ - -0.6 - - Marathon, leg 9 ref. 1300 dbar Zemba
28$^{\circ }S$ - - - 2.4 Meteor, 1925 ref. $\sigma _0$=27.4 3 SP
28$^{\circ }S$ - - - 5.4 Meteor, 1925 ref.$\sigma _0$=27.75 3 SP
28$^{\circ }S$ - - - 9.0 Meteor, 1925 ref. bottom SP
30$^{\circ }S$ $\approx$5 2/-5 2.5 5.5 WOCE A10 inverse model Holfort
31$^{\circ }S$ - -2.5 1.5 - Marathon, leg 9 ref. $\sigma _0$=27.1 3 Zemba
31$^{\circ }S$ - -2.5 - - Marathon, leg 9 ref. 1500 dbar Zemba
32$^{\circ }S$ $\approx$5 $\approx$-10 - 5 IGY inverse model Fu
32$^{\circ }S$ 5 -24 12 16 IGY mass conservation Rintoul
32$^{\circ }S$ - - - 3.4 IGY ref. $\sigma _0$=27.4 3 SP
32$^{\circ }S$ - - - 6.0 IGY ref. $\sigma _0$=27.75 3 SP
32$^{\circ }S$ - - - 7.6 IGY ref. bottom SP
34$^{\circ }S$ - -9 - - Marathon, leg 9 ref. bottom Zemba
34$^{\circ }S$ - -3.3 - - Marathon, leg 9 ref. 1700 dbar Zemba
36$^{\circ }S$ - -18.5 5.7 - Marathon, leg 9 ref. $\sigma_4$=45.8 3 Zemba
38$^{\circ }S$ - -19.8 - -   bottom velocity Peterson


 
 

Table 2: Positions of the oceanic fronts in the southern South Atlantic: Polar Front (PF), Subantarctic Front (SAF), Subtropical Front (STF) and Brazil Current Front (BCF). <49oS means south of the given latitude.
Longitude PF SAF STF BCF Cruise/Reference
shelf break - 40oS 38oS 37oS Stramma_Peterson:1990
$\approx$55oW 55oS 54.5oS - 43oS Feb/Mar 1984, Ikeda_et_al:1989a
$\approx$55oW 57oS 56oS - 38oS Jan 1985, Ikeda_et_al:1989a
$\approx$55oW 56.5oS 56oS - 39oS Jan 1986, Ikeda_et_al:1989a
$\approx$55oW 57oS 56oS - 40oS Mar 1987, Ikeda_et_al:1989a
50-55oW - 44oS 39-40oS 37-38oS Polarstern ANT XII/1, Schmid:1998
50oW - 49oS 47oS 42oS Stramma_Peterson:1990
41oW 49.5oS 48oS 38-40oS 33-36oS SAVE 5, Schmid:1998
40oW <49oS 48oS 42oS 36oS Stramma_Peterson:1990
35oW - - 38-40oS 33-35oS Meteor 28/2, Schmid:1998
25-37oW 49.5oS 48oS 41-42oS 34-36oS SAVE 5&6, Tsuchiya_et_al:1994
$\approx$18oW - 42-43oS 38-39oS 34-35oS SAVE 4, Gordon_et_al:1992
1oW 50oS 45-46oS 36-40oS - Ajax, Schmid:1998
8-18oW - - 38-40oS - ANT XIV/4, Schmid:1998
0-20oW 51oS 45-46oS 41-42oS 38-39oS Meteor 11/5, Roether_et_al:1990

 
 

Table 3: Depth and location of the Subantarctic Mode Water (SAMW) layer at several longitudes in the South Atlantic. The meridional extent of the Polar Frontal Zone (PFZ) is also given.
SAMW layer    
Longitude Latitude Pressure/dbar PFZ Cruise
41oW 49.5oS 100-400 48-49.5oS SAVE 5
25-37oW 49-49.5oS 150-450 46-49.5oS SAVE 5&6, Fig. 3
25-37oW 46-48oS 200-500 46-49.5oS SAVE 5&6, Fig. 3
$\approx$18oW 44-45oS 300-600 <43oS SAVE 4
1oW 47-49.5oS 100-300 46-50oS Ajax, Fig. 4
0-20oE 46-50oS 100-350 46-51oS Meteor 11/5

 
 

Table 4: Transports in the eastward branch of the subtropical gyre. (a) Position and geostrophic quasi-zonal transports M of the Antarctic Circumpolar Current (ACC) and the South Atlantic Current (SAC) in the layer$\sigma _0$= (27.00 - 27.35) 3. (b) Zonal Lagrangian transports M estimated from mean float velocities in 2$^{\circ }$ by 2$^{\circ }$ boxes. 500 m was used as thickness of the AAIW layer. The transport variability Mv was calculated from the standard deviations of the box means. Information on boxes with less than 30 float days is given in the last column.
(a)            
Longitude ACC SAC Cruise reference level
  Latitude M/Sv Latitude M/Sv    
52oW     46-37oS 26 Polarstern ANT XII/1 1500 dbar
41oW 52-47oS 27 44-38oS 18 SAVE 5 $\sigma _3$= 41.55 3
33oW     40-38oS 11 Meteor 28/2 p = 1500 dbar
30oW 52-44oS 13 43-40oS 16 SAVE 5&6 $\sigma _3$= 41.55 3
30oW 52-44oS 8 43-40oS 9 SAVE 5&6 p = 1500 dbar
1oE 53-44oS 25 41-37oS 6 Ajax $\sigma _3$= 41.55 3

(b)        
Longitude Latitude M/Sv Mv/Sv Latitude, transport, float days
42oW 42-36oS 15 20 39oS, -4 Sv, 7
        41oS, 19 Sv, 12
38oW 42-36oS 19 22 41oS, 14 Sv, 11
36oW 44-36oS 12 20  
34oW 42-38oS 10 12  
32oW 42-38oS 9 10  
28oW 42-36oS 9 11  

 

Table 5: Transports in the westward branch of the subtropical gyre. (a) Position and geostrophic quasi-zonal transports Min the layer $\sigma _0$= (27.00 - 27.35) 3. (b) Zonal Lagrangian transports Mestimated from mean float velocities in 2$^{\circ }$ by 2$^{\circ }$ boxes. 500 m was used as thickness of the AAIW layer. The transport variability Mv was calculated from the standard deviations of the box means. Information on boxes with less than 30 float days is given in the last column.
(a)          
Longitude Latitude M/Sv Cruise Reference level
1oE 33-27oS -13 Ajax $\sigma _3$= 41.55 3
22oW 31-22oS -6 Meteor 28/2 p = 1500 dbar
25oW 33-21oS -12 SAVE 5&6 $\sigma _3$= 41.55 3
25oW 33-21oS -7 SAVE 5&6 p = 1500 dbar
37oW 33-21oS -6 Polarstern ANT XII/1 p = 1500 dbar

(b)        
Longitude Latitude M/Sv Mv/Sv Latitude, transport, float days
30oW 34-25oS -18 5 25oS, -3 Sv, 10
32oW 36-26oS -18 8 35oS, -2 Sv, 28
34oW 34-20oS -19 9 33oS, -4 Sv, 20
36oW 34-20oS -29 10 33oS, -6 Sv, 28
38oW 36-20oS -22 12 35oS, -8 Sv, 6
40oW 36-20oS -19 12  
42oW 32-24oS -13 7 25oS, -4 Sv, 9 cycles

 

Table 6: Geostrophic quasi-meridional transports at the western boundary in the layer $\sigma _0$= (27.00 - 27.35) 3 referenced to $\sigma _3$ = 41.55 3. Mw = transport of the western boundary current. Mr = transport in the Brazil return current region.
Latitude Mw/Sv Mr/Sv Cruise
19.0oS 7.7 - WOCE A9
20.7oS 4.0 - Meteor 15/1-2
24.3oS 2.7 - Meteor 15/1-2
27.1oS -1.4 - Meteor 22/3
27.8oS -1.0 - Meteor 22/3
27.8oS -13.5 - Meteor 22/3
28.2oS -4.7 - Meteor 15/1-2
28.2oS -10.2 7.0 WOCE A10
     

 
 

Table 7: Maximum depth Hs of the subtropical gyre in different regions estimated with models of the ventilated thermocline using different depths He of the wind-driven layer at the eastern boundary. The models are: HR94 - Huang and Russell (1994), H90 - Huang (1990) LS - Luyten and Stommel (1986), LPS - Luyten et al. (1983).
area Hs/m He/m model Reference
North Atlantic > 950 800 LPS Luyten_et_al:1983
North Atlantic > 1130 1000 LS, only wind Arhan:1990
North Atlantic > 1064 1000 LS, with thermohaline flow Arhan:1990
North Atlantic 1750 - H90 Huang:1990
North Pacific < 1400 - HR94 Huang_Russell:1994
South Pacific > 1400 800 LPS DeSzoeke:1987
South Atlantic > 1200 800 LPS this study

 
 

Table 8: Configuration of the simulations. y1 and y2 are the subduction latitudes of layer 2 and 3, respectively. The mean densities of the layers 1 to 4 are given in the column $\overline {\sigma _0}$. He is the depth of the wind-driven layer at the eastern boundary. LPS represents the model by Luyten et al. (1983). PR indicates the model by Pedlosky and Robbins (1991).
Simulation y1 y2 $\overline {\sigma _0}$ in 3 He Model wind field
1 40oS 45oS 26.5, 26.8, 27.2, 28.0 800 m LPS ECMWF
2 40oS 45oS 26.5, 26.8, 27.2, 28.0 variable PR ECMWF
3 35oS 40oS 26.5, 26.8, 27.2, 28.0 800 m LPS ECMWF
4 40oS 45oS 26.5, 26.8, 27.2, 28.0 variable LPS ECMWF
5 40oS 45oS 26.5, 26.8, 27.2, 28.0, 800 m LPS ERS-1

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