Indian Ocean schematic surface circulation. Black: mean flows without seasonal reversals. Gray: monsoonally reversing circulation (after Schott & McCreary, 2001): (a) Southwest Monsoon (July-August). The ACC fronts are taken directly from Orsi, Whitworth, and Nowlin (1995). The subtropical gyre in the Southern Hemisphere just 200 m below the sea surface differs significantly from the surface circulation, as indicated by the dashed curve. Acronyms: EACC, East African Coastal Current; EICC, East Indian Coastal Current; EMC, East Madagascar Current; LH and LL, Lakshadweep high and low; NEC, North Equatorial Current; NEMC, Northeast Madagascar Current; and WICC, West Indian Coastal Current. See also Figure S11.1 from the textbook Web site, which is a surface height map based on Niiler, Maximenko, and McWilliams (2003), with labeled currents, and Figure S11.2, reproduced from Schott and McCreary (2001).

Indian Ocean schematic surface circulation. Black: mean flows without seasonal reversals. Gray: monsoonally reversing circulation (after Schott & McCreary, 2001): (b) Northeast Monsoon (January-February). The ACC fronts are taken directly from Orsi, Whitworth, and Nowlin (1995). The subtropical gyre in the Southern Hemisphere just 200 m below the sea surface differs significantly from the surface circulation, as indicated by the dashed curve. Acronyms: EACC, East African Coastal Current; EICC, East Indian Coastal Current; EMC, East Madagascar Current; LH and LL, Lakshadweep high and low; NEC, North Equatorial Current; NEMC, Northeast Madagascar Current; and WICC, West Indian Coastal Current. See also Figure S11.1 from the textbook Web site, which is a surface height map based on Niiler, Maximenko, and McWilliams (2003), with labeled currents, and Figure S11.2, reproduced from Schott and McCreary (2001).

Surface circulation. Left: Arabian Sea (surface drifters). Right: Bay of Bengal (ship drift). Top: Southwest Monsoon. Bottom: Northeast Monsoon. Source: From Schott and McCreary (2001).

Somali Current regime during the Southwest Monsoon (August/September, 1995). This figure can also be seen in the color insert. Source: From Schott and McCreary (2001).

Mean zonal surface currents at the equator, based on ship drift data. Left: monthly means. Right: annual mean. ©American Meteorological Society. Reprinted with permission. Source: From Han, McCreary, Anderson, and Mariano (1999).

SST in July 2003 (Southwest Monsoon), from the MODIS satellite. This color can also be seen in the color insert. Source: From NASA Goddard Earth Sciences (2007a).

Sections in the Somali Current upwelling regime at 12°N, 29 August–1 September 1964. Source: From Schott and McCreary (2001); after Swallow and Bruce (1966).

Adjusted steric height (10 m²/s²) at (a) 0 dbar. Source: From Reid (2003). The closely related geostrophic streamfunction based on subsurface float observations from Davis (2005) is shown in the supplement Figure S11.6 on the textbook Web site.

Adjusted steric height (10 m2/s2) at (b) 200 dbar. Source: From Reid (2003). The closely related geostrophic streamfunction based on subsurface float observations from Davis (2005) is shown in the supplement Figure S11.6 on the textbook Web site.

Adjusted steric height (10 m2/s2) at (c) 800 dbar. Source: From Reid (2003). The closely related geostrophic streamfunction based on subsurface float observations from Davis (2005) is shown in the supplement Figure S11.6 on the textbook Web site.

(a) Schematic of the Agulhas Current system and local topography. Source: From Schmitz (1995b). (b) RMS sea surface height variability for eight years from the Topex/Poseidon altimeter. Source: From Quartly and Srokosz (2003, Satellite observations of the Agulhas Current system, Phil. Trans. Roy. Soc. A., 361, p. 52, Fig. 1b). (c) Average velocity from 0–75 m depth and (d) velocity section at 36°S, with neutral density surfaces overlaid, from ADCP observations in February–March, 2003. Source: From Beal, Chereskin, Lenn, and Elipot (2006). Figures c and d are from the ©American Meteorological Society. Reprinted with permission.

Leeuwin Current (LC) and Leeuwin Undercurrent (LUC). Other acronyms: SEC, South Equatorial Current; LCS, Leeuwin Current source region; and GI, geostrophic inflow. Source: From Pearce (1991); from Schott and McCreary (2001).

Mean potential temperature (°C), salinity, potential density, and velocity (cm/sec) at 32°S in the Leeuwin Current. Shading indicates salinity of 35.5–35.7 psu. Source: From Feng et al. (2003).

Indonesian Archipelago and Throughflow with transports (Sv). Lower panel summarizes transport above and below 680 m (Makassar Strait sill depth). This figure can also be seen in the color insert. Source: From Gordon (2005).

(a, b) Red Sea Overflow Water: salinity with potential density contours overlaid on sections in the Gulf of Aden in February–March, 2001. North is on the left. Source: From Bower et al. (2005). ©American Meteorological Society. Reprinted with permission. (c) Red Sea outflow in the Gulf of Aden: climatological salinity on the isopycnal σθ = 27.20 kg/m³. Source: From Bower, Hunt,and Price (2000). This figure can also be seen in the color insert.

Salinity along 9°N with selected potential density σ_θ, σ₂, and σ₄ contours and station track overlaid. After the WOCE Indian Ocean Atlas, Talley (2011).

Adjusted steric height (10 m²/s²) at (a) 2000 dbar and (b) 3500 dbar. Source: From Reid (2003).

(a) and (b) Net northward (meridional) transport (Sv) for the Indian Ocean at 33°S, integrated from the bottom to the top. See also Figure S11.9 in the online supplementary materials. Source of (a): From Ganachaud, Wunsch, Marotzke, and Toole (2000). Source of (b): From Robbins and Toole (1997). The right-hand vertical coordinate is neutral density. (c) Neutral density (kg/m³) at 33°S. Heavy contour is isoneutral surface 27.95 kg/m³, marking the division between net northward flow below and southward above. After WOCE Indian Ocean Atlas, Talley (2011).

Sections at 33°S in 1987. (a) Potential temperature (°C). See Figure S11.10 on the textbook Web site for the corresponding oxygen section. Selected isopycnals used for maps in other figures are overlain (bold). Station locations are on the inset maps. Source: From WOCE Indian Ocean Atlas, Talley (2011); see also Toole & Warren (1993).

Sections at 33°S in 1987. (b) salinity. See Figure S11.10 on the textbook Web site for the corresponding oxygen section. Selected isopycnals used for maps in other figures are overlain (bold). Station locations are on the inset maps. Source: From WOCE Indian Ocean Atlas, Talley (2011); see also Toole & Warren (1993).

Mean T-S curves for the Indian Ocean.

(a) Station locations, (b) potential temperature (°C) — salinity and (c) potential temperature (°C) — oxygen (μmol/kg) for the Indian Ocean along 60°E. This figure can also be seen in the color insert. After the WOCE Indian Ocean Atlas, Talley (2011).

Salinity along 60°E, with potential density contours used for salinity maps. Station track is overlaid. After the WOCE Indian Ocean Atlas, Talley (2011).

Salinity at σ_θ = 26.0 kg/m³, at a depth of 150–200 m through most of the Indian Ocean. Source: From Reid (2003).

(a) Potential vorticity [10⁻¹⁴ (cm s)⁻¹] (shading), oxygen (light contours), selected isopycnals (dark contours) at 33°S in the Indian Ocean (see supplemental Figures S11.9 and S11.10 on the textbook Web site for additional oxygen and isopycnal contouring). The STMW and SEISAMW potential vorticity minima are labeled, as is the AAIW (salinity minimum).

(b) Potential vorticity [10⁻¹⁴ (cm s)⁻¹] on the neutral density surface γⁿ = 26.88 kg/m³, equivalent to σ_θ = 26.8 kg/m³, representative of SEISAMW. Source: From McCarthy and Talley (1999).

Salinity at σ₁ = 31.87 kg/m³ (equivalent to σ_θ = 27.3 to 27.4 kg/m³), at a depth of 900–1200 m in most of the Indian Ocean. Source: From Reid (2003).

Salinity maps. (a) At σ₂ = 37.0 kg/m³, at about 2600 m depth, representative of the deep waters. (b) At σ₄ = 45.89 kg/m³, at about 3500 m depth, representative of the bottom waters. Source: From Reid (2003).