I' Distribution of Oceans and Seas

1
I. Distribution of Oceans and Seas

• Sea and oceans account for 71 of the total area
  of the earths surface.
• They are not evenly distributed and most of them
  are found in the Southern Hemisphere.
• The 4 largest oceans of the world are
• Pacific Ocean
• Atlantic Ocean
• Indian Ocean
• Arctic Ocean

2
I. Distribution of Oceans and Seas

• At the margins of the oceans next to continents,
  seas can be found, e.g.
• North Sea,
• Mediterranean Sea,
• Nan Hai
• Which ocean and which sea is Hong Kong facing?
• Hong Kong is facing the Nan Hai and the Pacific
  Ocean.

3
II. How Oceans affect our climate?

• Q1. Most of the water is stored in the
  oceans.
• Q2. Water returns to the oceans by rivers.
• Q3. Most evaporation comes from the oceans.
• Q4. Yes, it is because onshore wind brings
  clouds from ocean to land.
• Q5. Our water supply mainly comes from
  precipitation to the land.

4
II. How Oceans affect our climate?

• Oceans are huge reservoirs of moisture and heat,
  which regulate the rainfall and temperature.
• Coastal areas receive the biggest influence from
  oceans. Therefore, oceans greatly affect our
  climate.

5
II. How Oceans affect our climate?

• 1a) Relief rain
• Air rises and cools when it meets a mountain.
• Condensation occurs and clouds form. Relief rain
  mainly falls on the windward slope.
• Leeward slope receives less rainfall because it
  is in the rainshadow region.

6
II. How Oceans affect our climate?

• 1b) Typhoons
• 1c) Fog

7
II. How Oceans affect our climate?

• 2a) Maritime Climate
• Water absorbs and loses heat slower than the
  land.
• Therefore, in summer, the oceans heat up slower
  than the land.
• The temperature is lower in the oceans.
• In winter, the oceans cool down slower than the
  land.
• The temperature is higher in the oceans.

8
II. How Oceans affect our climate?

• As a result, coastal locations enjoy a cooler
  summer and warmer winter when compared to inland
  regions.
• This is known as maritime climate.

9
II. How Oceans affect our climate?

• 2b) Warm and cold ocean currents
• Ocean currents are large scale movements of
  surface water in the oceans which can regulate
  the temperature of coastal areas.
• El Nino is the phenomenon of an unusual increase
  in ocean temperature over the tropical Pacific
  Ocean.

10
III. What are ocean resources?

• 1. Source of food
• Most marine life is found on the continental
  shelf, which provides 20 of the worlds animal
  protein.
• 2. Source of minerals
• e.g. tin, gold, diamond, salt.
• 3. Source of energy
• Fossil fuels such as gas, oil and coal can be
  found in the rock layers beneath the seabed. Sea
  waves and tidal currents can also generate
  electricity.

11
III. What are ocean resources?

• 4. Trade and shipping
• 5. Ports and settlement
• 6. Recreation