Chapter 22 - Oceanography
• Oceanography 
• What percentage of
the Earth is covered
with water? 
• The scientific study of
the ocean
• 70% covered by water
• 30% is covered by land
• How do scientists
study the ocean
floor? 
•
•
•
•
•
Sonar
Satellites
Deep-sea corers
Magnetic recorders
Robotic vehicles
Properties of Water
• Density 
• Freezing point 
• Boiling point 
• Ice is less dense than
liquid water because
water EXPANDS as it
freezes
• Salt water is MORE
dense than fresh water
• 0oC and 32oF
• 100oC and 212oF
Properties of Salt Water
• Salinity 
• Salinity of ocean
water is 
• The measure of
dissolved salts in
water
• 35 grams of salt per
1000 grams of sea
water……or 35o/oo
Composition of Seawater
• The two most
abundant ions in
seawater are 
• Na = 30% (sodium)
• Cl = 55% (chlorine)
• NaCl is sodium
chloride (table salt)
Temperature in the Oceans
• Mixed Layer
(Surface) 
• Most energy
exchanged!!!!
• Thermocline 
• Rapid change in
temperature
• Deep water 
• Cold and no sunlight
received