Unit 10 Review Key -Ocean Currents (Page 3 of 3) in pdf

Unit 10 Review Key -Ocean Currents Page 3

17. What are some climate effects of La Nina? North America experiences colder than normal weather. There are les

Typhoons in the Pacific and more Hurricanes in the Atlantic. Fish populations thrive off the coast of South

America due to increased upwelling.

18. How does El Nino affect upwelling and the fisheries off the coast of South America? Upwelling of cold deep

nutrient rich waters slows or stops during an El Nino. This cuts off the nutrients necessary to maintain the food

web along the coast of South America. As a result fish populations crash as do populations of other species that

rely on fish such as seabirds.

Deep Water Currents

19. What is the primary force that drives deep water currents? They are driven by differences in density that are

caused by differences in temperature and salinity. This is called thermalhaline circulation.

20. What two factors affect thermohaline circulation? temperature and salinity

21. What is the Global Conveyor Belt? It is the global circulation pattern of deep ocean currents.

22. Where does it start? In the North Atlantic when cold salty dense water sinks and begins to move south.

23. How does the Global Conveyor Belt and ocean currents affect atmospheric carbon dioxide? The oceans are a

carbon sink. The Global Conveyor Belt carries dissolved carbon dioxide and carbon from plankton away from the

atmosphere and sequesters it in the deep oceans for thousands of years.

Unit 10 Review Key -Ocean Currents Page 3