Oceans

Ocean-Atmosphere Links Exchange of water, carbon dioxide and heat. Surface ocean currents are driven by atmospheric circulation. Oceans and atmosphere control climate.

Ocean-Atmosphere Links Gases and Dust Fig. 9.9

Atmospheric Water Source Around equator – precip. exceeds evap. Around 30 o N/S lat. – evap. exceeds precip. Fig. 9.9

Oceans and Climate Q. Why is the climate in England mild even though it's at 55 o N latitude?

Oceans and Climate A. The Gulf Stream current carries heat to Northern Europe. Fig. 9.14

Dissolved Ions in Ocean Water Major ions: Sodium (Na) Chloride (Cl) 85% Minor ions: Sulfate (SO 4 ) Magnesium (Mg) Calcium (Ca)

Daily Questions Q. Where do all the dissolved ions in ocean water come from? A. Chemical weathering of rocks and minerals. Q. Why are the oceans so much saltier than rivers and lakes? A. Rivers deliver water and dissolved ions to oceans, only water leaves oceans as evaporation.

Salinity and Latitude Figure13.9

Salinity and Depth Figure 13.10

13.11

Ocean Temperature vs. Depth Figure 13.13

Density versus Depth Density a function of Temperature (generally, as T ↓ density↑ ) Salinity (as Sal ↑ density ↑) Density differences divided ocean column into 3 Shallow Middle Bottom Fig

Layers of the Ocean Surface Layer: 2% of water warm, well mixed biologically productive Fig. 9.10

Layers of the Ocean Deep Zone: 98% of water cold, uniform temperature isolated from the atmosphere nutrient rich Fig. 9.10