Ocean currents Flashcards
Surface/deep, factors influencing, Global Conveyor Belt, Gulf Stream (20 cards)
Define ocean currents
Move water horizontally and vertically on local and global scales
What role do ocean currents play in heat energy transfer and storage?
Currents essential to both. Water holds onto heat more effectively than air. Oceans cover 71% of planet.
What are 3 effects of the movement of heat through currents?
- Regulation of local weather
- Stabilisation of global climate patterns
- Delivery of nutrients to marine ecosystems
Name 5 factors that influence currents
- Wind
- Tides
- Coriolis effect (rotation)
- Solar energy
- Water density
What usually drives surface currents?
Wind
Are surface currents horizontal and vertical?
Yes, horizontal (e.g. rips) and vertical (e.g. upswelling)
What typically drives deep ocean currents?
Density
What is water density influenced by?
Temperature, salinity, depth of water
Is colder, saltier water more or less dense?
More
What is the longest ocean current in world?
Global conveyor belt
Does Global conveyor belt involve both surface and deep ocean currents?
Yes
Do warm surface currents carry less dense water away from or towards the Equator?
Away- to poles
Does water becomes more or less dense as it travels towards poles?
More- density increases as it cools and more freshwater evaporates- increasing salinity
How long does it take for the global conveyor belt to circulate globe?
1000 years
Is climate change contributing to the increase or decrease in speed of the global conveyor belt?
Decreasing speed
Why is climate change affecting global conveyor belt?
Increasing ocean temps, evaporation of seawater, glacial ice melting. Disrupts sinking of denser, colder salty water.
Define the Gulf Stream
A warm, powerful ocean current that forms part of the Global Conveyor Belt.
Where is the Gulf Stream?
From Gulf of Mexico along east coast of US and across Atlantic Ocean to Europe
Why does the Gulf Stream flow clockwise?
Coriolis effect- drives wind/water to the right in northern hemisphere
T or F- warmer water from tropics move up in Gulf Stream and become cooler and saltier in the North Atlantic
T
