Transcript 2.5 Ocean Currents & Climate

Ocean Currents & Climate
• Understand the cause of ocean
currents and how they affect climate
• Chapter 4
• P. 68-69
Define “ ocean current”
Ocean currents:
1. Permanent or semi-permanent horizontal
movement of surface water (100m)
2. It is unusually cold or hot
3. Caused by:




prevailing winds
variations in temperature & solar heating
density of water
coriolis force
Explain how ocean currents affect climate
on nearby land.
Affect of cold ocean currents
 Cools the summer temperature
 Reduces precipitation; cooler air holds less moisture!!
Explain how ocean currents affect climate
on nearby land.
Affect of warm ocean currents
– Warms the winter temperature
– Increases precipitation; warmer air holds more
moisture!!
Practice - How is each location affected by the ocean
current?
1. Mary’s Harbour, NL - Labrador current
•
Cool summer temperatures & surprising little
precipitation
A
Practice - How is each location affected by the
ocean current?
1. Mary’s Harbour, NL - Labrador current
•
•
•
Cool summer temperatures
Surprising little precipitation despite being a coastal
area
..again cold air holds LESS precipitation!
2. Brazilia & Brazil Current
– High precipitation.
– Precipitation is further increased by the fact that the
southeast trade winds blow off the warm ocean current
onto the land.
B
Practice - How is each location affected by the
ocean current?
1. Mary’s Harbour, NL - Labrador current
•
Cool summer temperatures & surprising little
precipitation despite being a coastal area
2. Brazilia & Brazil Current
– Main effect Warm moist air
– High precipitation.
– The southeast trade winds blow off the warm ocean
current onto the land.
3. Look At figure 4.7 on page 60 and explain why
Cape Town, South Africa might have similar fog
conditions as St. John’s NF?
C
Practice - How is each location affected by the
ocean current?
1. Mary’s Harbour, NL - Labrador current
•
Cool summer temperatures & surprising little
precipitation despite being a coastal area
2. Brazilia & Brazil Current
– Warm moist air = high precipitation.
– The southeast trade winds blow off the warm ocean
current onto the land.
3. Look At figure 4.7 on page 60 and explain why
4.
Cape Town, South Africa might have similar fog
conditions as St. John’s NF?
Australia has a fair amount of desert. Looking at
figure 4.7 on p. 60 which coast would you expect
it to be on, east or west?
D
Practice - How is each location affected by the
ocean current?
1. Mary’s Harbour, NL - Labrador current
•
Cool summer temperatures & surprising little
precipitation despite being a coastal area
2. Brazilia & Brazil Current
– Warm moist air = high precipitation.
– The southeast trade winds blow off the warm ocean
current onto the land.
3. Look At figure 4.7 on page 60 and explain why
4.
Cape Town, South Africa might have similar fog
conditions as St. John’s NF?
Australia has a fair amount of desert. Looking at
figure 4.7 on p. 60 which coast would you expect
it to be on, west - colder winds=less precip.