Midterm 1 Flashcards
What is the average depth and deepest point of the ocean?
Average depth is ~4,000 m (~2.5 miles) (deepest point is > 11,000 m; 6.8 miles).
Water is an excellent _______.
Solvent
If ice did not float, the
ocean would freeze from the ____________.
Bottom up
The major ions found in seawater are ________ and _______, followed by
_________, ____________, ____________, __________, and __________.
chloride and sodium, followed by
sulfate, magnesium, calcium, potassium and bicarbonate
What symbol is used to denote parts per thousand?
‰
What is the average salinity of the open ocean?
~ 32 ‰ to ~ 37 ‰ (average 35)
What is brackish?
anywhere between full
salinity and 0 ‰
Vertically, temperature is relatively constant across the ____________ of the ocean, but then drops rapidly through a ________, where wave and current action ______________ the waters.
mixed layer (surface layer), thermocline, no longer mix
_______________ are driven by winds, and ultimately by the uneven heating of the Sun at the equator vs. higher latitudes.
Surface currents
What do currents do?
Currents are responsible not only for the redistribution of heat, minerals,
and nutrients in the ocean, but also for the dispersal of many organisms.
Tides are…
Periodic changes in sea surface height, which at the sea shore can give the appearance of the ocean, over the course of hours, first encroaching upon and then retreating from the land.
What is the intertidal zone?
The intertidal zone is the area of the sea shore that is covered by water at
least once in a tidal cycle, and is exposed to air at least once in a tidal cycle
What environmental changes does the intertidal zone experience?
Temperature fluctuations (from freezing to extreme heat)
2. Oxygen fluctuations (from anoxia (no oxygen) to super-saturation)
3. Desiccation, or drying out
What two forces create tides?
gravitation and inertia
