Physical Oceanography Flashcards
What is the average depth of the ocean?
3.8km
Whats the ~ width of the continental shelf?
~65km
What is the aspect ratio of the ocean (width: depth)?
2500:1
What is the temperature range of the ocean?
-2°C at the poles to 28°C at the equator
What is the primary influence of the ocean temperature?
air-sea interface
inertia
Trägheit
Compare the thermal inertia of the ocean compared to the atmosphere
- energy required to heat the atmoshpere by 1°C would only heat up the first 2m of the ocean
- from the greenhouse effect, ocean has taken 20x as much heat, but warmed up less then the atmosphere.
How deep is the mixed surface layer of the ocean?
ca. 100m
What is the weight percentage of the salt in the ocean?
3.5 %
also called 35 psu (practical salinity units).
Is the salinity equally distributed?
Nope:
- varying geographically: according to evaporation, precipitation, rivers, ice formation and ice melt
- salinity changes with depth: halocline!
* in cold water the halocline helps stabilizing the water column, lower salt above allowing the formation of ice, increasing. where heavy evaporation more salt above, which is heavier, resulting in mixing.*
How much does the pressure increases with depth in the ocean?
1 bar per 10 meters
(or 1 atmosphere per 10 meter)
Pressure is one of the major driver for ….. in the ocean.
circulation
On which three factors does the density in the ocean depens on?
- salinity
- pressure
- temperature
give a range for seawater density
1020 – 1030 kg/m
the average density is 1025 kg/m!
Connection between pressure and density
?
water becomes denser with increasing density
what are the properties of
lighter water vs. heavier water?
lighter water: warmer, fresher
heavier water: colder, more saline
whats a pycnocline?
sharp density cline
name for sharp density cline
pycnocline
Dissolved oxygen is an indicator for what?
when the water was last in contact with the athmosphere
Name conservative and unconservative tracers
- *unconservative**:
- dissolved oxygen
- phosphate, nitrite, silicate (usually found away from surface the socalled euphotic zone)
- *conservative**:
- radioactive elements (tell something about turnover rates)