Upwelling, downwelling and the deep ocean Flashcards
How many layers are in the ocean?
2
Is there a transfer in heat between the two layers?
No because there is a massive difference in density
Why are vertical changes important ?
- Transfer of energy/heat
- Primary production
What is upwelling?
Ekman transport pushes surface water away from the coast which means the water from depth gets sucked up to the surface
How does wind effect upwelling?
If it is in the same direction it can cause upwelling to increase
What causes upwelling at the shelfs edge?
Tides
Positives of upwelling and mixing on the shelf
- Brings nutrients into the euphotic zone
- Supports a range of ecosystems
- Supports about 90% of world’s fisheries
Equatorial upwelling
Ekmann transport on both sides of the equator, the only way to fill this gap is for water from depths to rise, this pushes the warm water apart
What are eddies?
Rotating storms in the water
Depending in which direction they go they can pull water up or push water down, circular currents of water
In the northern hemisphere which way does the Coriolis force deflect water?
To the right
What is downwelling?
Ekman transport pushes water towards the coast line
What are vertical movements driven by?
Density
What is thermohaline circulation?
It is circulation driven by temperature and salinity which causes changes in density
What causes deep convection?
Surface density is low
Deep water formation
We need this
Drives the overturning circulation
