16-1 Flashcards
(29 cards)
What are ocean currents?
Masses of water that flow from one place to another
What is the Gulf Stream? How was it discovered?
A large famous ocean current, discovered because of a mail delivery problem
How wide and deep is the Gulf Stream and how much volume does it carry compared to the Mississippi River?
30 km wide, 300 m deep. it carries 100 times greater volume
What causes surface currents?
Friction between wind and water surface, follows atmospheric wind patterns
What colors represent warm and cold currents?
Red = warm currents, blue = cold currents
What are gyres?
Huge circular-moving currents that move within an ocean basin
How many main gyres are there?
Five main gyres
What effect helps create ocean currents? what is it?
Coriolis effect. Deflection of currents away from their original course as a result of Earth’s rotation
In which direction do wind and ocean currents rotate in the northern hemisphere? southern hemisphere?
northern: Clockwise
southern: counterclockwise
What factors control ocean currents?
Wind and continents that deflect currents
How do ocean currents affect climate on western coasts? eastern coasts?
western coasts: Currents are cold and bring cool dry weather
eastern coasts: Currents are warm and bring warm moist weather
What role do ocean currents play in Earth’s heat balance?
Carry heat away from tropics to polar areas
What are upwellings?
When cold water from the deep ocean rises to the surface
What happens to nutrients during upwellings?
They are brought to the surface for fish and plankton
What is ocean pollution?
When harmful products, chemicals, or substances are introduced into the ocean
What are the primary causes of ocean pollution?
Natural occurrences and human occurrences
what are the 4 human occurances when pollutants from land reach the ocean by?
- Being dumped directly into the ocean
- Materials lost overboard accidentally during storms/shipwrecks
- Some pollutants in the air enter ocean through rain
- Other pollutants carried by rivers
What is an algae bloom?
Rapid reproduction of plant plankton due to fertilizers and sewage
when they die they decompose which uses up oxygen. other organisms can’t get enough oxygen and die.
What chemicals can affect marine organisms?
Metals like lead, mercury, and PCPs
What can solid wastes in the ocean do to animals?
Entangle and drown them
What causes oil spills?
Tanker collisions, leaks at offshore oil wells
What are density currents?
Deep currents caused by differences in density of ocean water
What effect does higher salinity have on water density?
Creates more density
Where does most water involved in density currents originate?
Near poles
