Oceans. Ocean-Atmosphere Links Exchange of water, carbon dioxide and heat. Surface ocean currents...

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

Gasesand Dust

Fig. 9.9

Atmospheric Water SourceAround equator – precip. exceeds evap.

Around 30o 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 55o 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 (SO4)•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

13.13

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. 13.14

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