Major Ocean Currents and Circulation Patterns

1. pg. 48 List 5 observation about the current map you drew on Thursday

2. Monday, October 23rd • Objective: I will identify the major ocean currents and circulation patterns. • Agenda: • Current Notes pg. 51 • Homework: • None

3. Pg. 51Currents • = a large mass of continuously moving water. • Surface Ocean Currents – the largest currents that move across the ocean; they are like rivers that travel long distances. • usually caused by wind. • Deep Ocean Currents – warm water rises at the equator, flows until it cools, and sinks at the poles. This cold water flows along the bottom toward the equator where it warms and rises.

4. Causes of Currents • Three major factors that set ocean currents in motion: • Wind • Changes in sea level • Differences in water density

5. Coriolis Effect • The spinning Earth causes the winds and surface waters to move in a clockwise direction in the North (deflected to the east) and in a counterclockwise direction in the South (deflected to the west). • The continents deflect the currents, causing them to move in giant circles called gyres. • Wind driven currents are also called surface currents • Significant b/c they move plankton across the ocean.

6. Upwellings • The rising of vertical currents from the deep. • Significant b/c nutrients such as phosphates and nitrates are brought up. These are important for the growth of plankton = plankton are at the beginning of the food chains. • Caused by wind blowing offshore or sometimes parallel to shore & the Coriolis effect

7. RTW pg. 48 How do currents benefit life on earth? Tuesday, October 24th • Objective: I will identify the major ocean currents and circulation patterns. • Agenda: • Great Pacific Garbage Patch Article pg. 53 • Homework: • None

8. Annotate & highlight text and circle unknown words Start brainstorming, we will answer this tomorrow: Using support from the text, defend or refute the following statement: • Threats posed to marine life (like entanglement, resin pellets, and water pollution by way of photodegradation) are ultimately caused by the oceanic gyres.

9. No RTW, instead…Grab your iPad Wednesday, October 25th Go to: www.padlet.com/ltbarker/vocab List a word that you didn’t know in the article Or define any of the words your peers listed and provide it in a separate text box

10. Pg. 52 Using support from the text, defend or refute the following statement: • Threats posed to marine life (like entanglement, resin pellets, and water pollution by way of photodegradation) are ultimately caused by the oceanic gyres.

11. Pg. 48 RTW: What do you already know about El Niño? Thursday, October 26th • Objective: I will be able to understand how currents effect the world’s climate • Agenda: • Check current map & article response • Current/El Niño Notes pg. 55 • Homework: None 

12. Ocean Currents

13. Surface Currents Represent large scale horizontal movement of water Occur in regions where winds blow over ocean w/ constancy of direction & velocity

14. Major ocean currents of the world. On this illustration red arrows indicate warm currents, while cold currents are displayed in blue.

15. Gulf Stream Average speed- 8 km/hr Surface temperature- 24ºC Responsible for the climate of England & Ireland

17. Wind Belts • Trade winds-near 15ºN latitude, blow from NE to SW • Westerlies- in the middle latitudes, blow from W-SW

18. Polar easterlies- at very high latitudes, blow from E to W All have a mirror image counterpart in the S. Hemisphere

19. Some currents transport more than 100X the volume of all earth’s rivers combined. • This greatly affects the distribution of marine organisms

20. Coriolis Effect • Water does not move parallel with wind direction • The spinning of the earth causes the winds & water to move in a clockwise direction in Northern Hemisphere

21. Water is deflected • Northern Hemisphere-Right • Southern Hemisphere-Left • Gyres-giant circles caused by continents deflecting currents

22. Vertical H20 Movement • Produced by sinking & upwelling • Break down the vertical stratification established by the Thermocline • Deep ocean circulation may take hundreds to thousands of years

23. Sinking • Caused by increased density • Higher latitudes • Highly Oxygenated

24. Upwelling • Brings deeper nutrient-rich waters to the surface • Cause for the areas of high productivity • Several of the world’s important fisheries are in these regions

25. El Niño • Changes in ocean surface winds and water temperatures • On a 5-7 year cycle • Responsible for the decline of coastal marine population

26. Trade winds from the east relax • Movement of water to the west decreases • Upwelling is blocked • During severe years, fish and bird populations disappear

27. Typical

28. Reversed Conditions

31. Pg. 48 RTW: List an observation about this picture

32. Thursday, October 13th • Objective: I will be able to understand how currents effect the world’s climate • Agenda: • The GLOBE Earth Systems Activity Day 1 • Homework: • Study for Current Test next week