1 Surface Circulation Pathways Generally, warm currents move poleward and cool currents move equatorward.

2 Effect of Ocean Heat Transport Pattern of currents flow impacts sea surface temperatures and, as a result, air temperatures over land.

3 Equatorial Pacific: Sea Surface Temperature (SST)

4 El Nino Effects on Winter Air Temperatures in US Temperature anomaly is plotted (T obsv’d – T mean )

5 Effect of El Nino on Anchovy Catch Declines in fish catch correlate with El Nino events (red spikes).

6 Atmospheric CO 2 Budget 1990s gm C yr -1 Fossil Fuel Combustion6.3±0.4 Deforestation1.7±1 Total Human CO 2 Source8.0±1.1 Atmospheric CO 2 Accumulation3.2±0.1 Ocean CO 2 Uptake2.0±0.4 Terrestrial CO 2 Uptake (by difference) 2.8±1.1 Total CO 2 Sink4.8±1.5

7 Anthropogenic CO 2 Distribution in the Ocean CO 2 from fossil fuel combustion that has been absorbed by the ocean is found mostly in the upper 1000m.

8 Photosynthesis Rates in the Ocean (satellite based estimates) Where are the highest (red/yellow) and lowest (blue) photosynthesis rates found in the ocean?

9 Sea Surface Temperature (SST)

10 Depth vs Pressure Density vs TemperatureDensity vs Pressure

11 CTD Measurements (pressure, temperature and conductivity)

12 Equation of State for Seawater

13 Density has non-linear dependence on T and S Range in T, S and σ in the ocean

14 Dependence of temperature of maximum density and freezing point of seawater on salinity Implies that cooling seawater with S<25 reaches the temperature of max density before the freezing point.

15 Cross Section of Potential Temp in Atlantic Ocean

16 Depth Profiles of Temperature 7ºS 01020ºC 63ºS

17 Sea Surface Temperature (SST) Most of surface ocean is warm. Only few regions at high latitudes where surface ocean temperatures approach temperatures in the Deep Sea. (ºC)

18 Surface Solar Radiation (Watts/m 2 ) The equatorial region with highest solar radiation rates corresponds to the warmest SSTs.

19 Potential Temp Variations: 50m vs 2000m in Pacific

20 Sea Surface Salinity

21 Evaporation and Precipitation Effects on Surface Salinity

22 Salinity Cross Section in Atlantic Ocean

23 Salinity Variations at the surface and 3000m in Pacific

24 Sea Surface Density and SST: Pacific Ocean The pattern of surface density closely follows the pattern of SST (but not surface salinity). Potential Density

25 Spatial variations of density- surface vs 3000m Potential Density 50mPotential Density 3000m Water is denser and more uniform in Deep Sea than surface ocean. Only near Antarctica in Pacific Ocean does surface potential density approach that of deep sea.

26 Cross Section of Density (σ θ ) Pacific Ocean Latitude Depth (m)

27 Depth Profiles of Density (σ t )