WATER and SEAWATER

Trujillo and Thurman, 10^th, Chapter 5: omit boxes

Objectives: Students should be able to

1. discuss how water is a unique substance
2. discuss the unusual thermal properties of water (compared to similar substances)
3. describe the processes that influence the salinity of seawater
4. discuss what residence time of an substance can tell us
5. describe in detail the relationships of temperature, salinity, pressure and density of water
6. describe processes of desalination

Unique nature of water: dipolar molecule, universal solvent

Thermal Properties

· Related to structure of water molecule

· Freezing and boiling points, latent heat

· Heat transfer during evaporation and condensation

· Heat Capacity

Dissolved components in seawater

· Major constituents of sea salt (salinity): Cl^-, Na⁺, SO₄^2-, Mg²⁺, Ca²⁺, K⁺

· Principle of constant proportions

· Steady state: in terms of salinity; processes affecting salinity; residence time

· Acidity of seawater – impact of atmospheric input

· Variations in surface ocean salinity: Why does it happen?

· Desalination processes

Density

· Influence of salinity, temperature, pressure

· Variations with depth in ocean: surface ocean, zone of transition (pycnocline, halocline, thermocline), deep ocean