FIGURE 3.1 Values of density  t (curved lines) and the loci of maximum density and freezing point (at atmospheric pressure) for seawater as functions of temperature and salinity. The full density  is  t with units of kg/m 3. TALLEY Copyright © 2011 Elsevier Inc. All rights reserved

FIGURE 3.2 The relation between depth and pressure, using a station in the northwest Pacific at 41° 53’N, 146° 18’W. TALLEY Copyright © 2011 Elsevier Inc. All rights reserved

FIGURE 3.3 (a) Potential temperature (  ) and temperature (T) (°C), (b) conductivity (mmho), and (c) salinity in the northeastern North Pacific (36° 30’N, 135°W). TALLEY Copyright © 2011 Elsevier Inc. All rights reserved

FIGURE 3.4 Increase in density with pressure for a water parcel of temperature 0°C and salinity 35.0 at the sea surface. TALLEY Copyright © 2011 Elsevier Inc. All rights reserved

FIGURE 3.5 Potential density relative to (a) 0 dbar and (b) 4000 dbar as a function of potential temperature (relative to 0 dbar) and salinity. Parcels labeled 1 have the same density at the sea surface. The parcels labeled 2 represents Mediterranean (saltier) and Nordic Seas (fresher) source waters at their sills. TALLEY Copyright © 2011 Elsevier Inc. All rights reserved

FIGURE 3.6 (a) Potential density and (b) Brunt-Väisälä frequency (cycles/h) and period (minutes) for a profile in the western North Pacific. TALLEY Copyright © 2011 Elsevier Inc. All rights reserved

FIGURE 3.7 For station Papa in the Pacific Ocean at 39°N, 146°W, August, 1959: (a) temperature (°C) and salinity (psu) profiles, (b) corrections to sound speed due to salinity, temperature, and pressure, (c) resultant in situ sound-speed profile showing sound-speed minimum (SOFAR channel). TALLEY Copyright © 2011 Elsevier Inc. All rights reserved

FIGURE 3.8 Sound ray diagrams: (a) from a shallow source for a sound-speed profile initially increasing with depth in upper mixed layer to a shallow minimum and then decreasing, and (b) from a sound source near the speed minimum in the sound channel for a typical open ocean sound-speed profile. TALLEY Copyright © 2011 Elsevier Inc. All rights reserved

Schematic of optical processes in seawater. Adapted and simplified from Mobley (1995), with added indicators of seawater heating and photosynthesis, as well as satellite observation of ocean color. TALLEY Copyright © 2011 Elsevier Inc. All rights reserved FIGURE 3.9

FIGURE 3.10 (a) Attenuation coefficient k, as a function of wavelength  (mm) for clearest ocean water (solid line) and turbid coastal water (dashed line). (b) Relative energy reaching 1, 10, and 50  depth for clearest ocean water and reaching 1 and 10 m for turbid coastal waters. TALLEY Copyright © 2011 Elsevier Inc. All rights reserved

FIGURE 3.11 Example of observations of water-leaving radiance observed by the Multi-angle Imaging Spectro Radiometer (MISR), with bands observed by satellite color sensors indicated. Solid curves: low chlorophyll water (0.01 mg/m3). Dotted curves: high chlorophyll water (10.0 mg/m3). The two lower curves have the atmospheric signal removed. (H. Gordon, personal communication, 2009.) TALLEY Copyright © 2011 Elsevier Inc. All rights reserved

FIGURE 3.12 Schematics of polynya formation: (a) latent heat polynya kept open by winds and (b) sensible heat polynya kept open by tidal mixing with warmer subsurface waters (after Hannah et al., 2009). TALLEY Copyright © 2011 Elsevier Inc. All rights reserved