Problem 1
From the cliffs of La Jolla, you look out over the ocean at the breaking waves rolling in
over the beach. You notice the water nearest the beach (within about 10-20 meters) is
cloudy and brownish. Further offshore the ocean is deep blue except for a long, narrow
swatch of cloudy water extending from the beach about 200 meters offshore and ending
with a broad mushroom-cap shape. This is indicative of a:
Ekman current
Turbidity current
Geostrophic current
Longshore Current
Rip Current
Ocean gyre current
You enter the ocean off La Jolla Shores in the summer in the area designated for
swimming only, and you start body surfing in the waves breaking pleasantly along the
shoreline. About 10 minutes later, you notice that surfers are all around you and the
lifeguard is yelling something over his bullhorn because you have moved about 100
meters northward into the surfing-only area. This is indicative of a:
Ekman current
Turbidity current
Geostrophic current
Longshore Current
Rip Current
Ocean gyre current
The European explorers of the New World quickly learned to take the “southern route”
from Europe to America (along 20N latitude) and the “northern route” (along 40N
latitude) when returning. This is indicative of a:
Ekman current
Turbidity current
Geostrophic current
Longshore Current
Rip Current
Ocean gyre current
While rapidly sailing directly downwind in the Bahamas, you toss a daisy overboard and
notice it floats away from the schooner at a 45-degree angle to the right of the direction
you are sailing. This is indicative of a:
Ekman current
Turbidity current
Geostrophic current
Longshore Current
Rip Current
Ocean gyre current
Problem 2
On a hot sunny day in July, you arrive at Swami’s Beach in Encinitas and find gentle
waves and VERY CHILLY water when you dash into the sea. You notice the wind is
blowing pretty strongly.
You immediately recognize this VERY CHILLY water is due to:
Global “dimming”
Cold wind blowing from the Arctic latitudes
Thermohaline circulation
Streamflow runoff from snow-fed mountain streams
Upwelling by Ekman transport
Ocean gyre circulation
Mixing of deep thermocline waters by wave breaking
Can you immediately guess the direction of the wind?
From ocean to land (westerly wind)
From land to ocean (easterly wind)
From north to south (northerly wind)
From south to north (southerly wind)
As the afternoon passes and the sun starts to set, the wind stops blowing strongly. From
what direction would you expect the light breeze that kicks up a couple hours after the
sun goes down to come from?
From ocean to land (westerly breeze)
From land to ocean (easterly breeze)
From north to south (northerly breeze)
From south to north (southerly breeze)
What would that breeze be called? (two word answer)
Problem 3
Shown is a time series of tropical Pacific sea-surface temperature (SST) in the Nino-3
region (see lower figure). Major El Nino events are often designated by those years that
have SST anomalies greater than 2 deg C in the Nino-3 region.
List the years of the major El Ninos.
(These “years” are usually associated with peak warming during boreal “winters” like
Dec 1920 - Feb 1921 => El Nino of ’20-’21)
Are there are any major La Nina events by this definition? (SST < -2 deg C)
Pourquoi?
Nino-3 area is the BOX in the eastern tropical Pacific.
Problem 4
Sketched below is the conceptual model of the “Great Ocean Conveyor Belt”.
This pattern of ocean circulation is predominantly forced by:
Global Winds
Raining and evaporating
Cooling and heating
Geothermal heating, hydrothermal vents, and seep-sea volcanism
Ocean bathymetric features
Another name for this type of ocean circulation is ______________ (one word answer).
If this circulation slowed down, as some have suggested might occur under global
warming conditions, the weather over Europe might get (warmer or colder).
Problem 5
The hole in this figure is an example of a _______________.
The steep rocky bluff would be termed a _______________.
This is an example of a ________________.
This is an example of a _________________.
Problem 6
From a liter of seawater with salinity 17 %o (parts per thousand), you determine from
chemical titration that it has 0.2 grams of Calcium and 1 mg of Manganese. What
amounts of Calcium and Manganese would you expect to find in seawater with salinity
34%o ?
What is the most abundant element (by mass) in seawater?
Where does ocean salinity tend to be the highest?
In deeper waters
Near river mouths
At “desert” latitudes
Near the equator
Near the poles
Problem 7
What is Surf?
Capillary waves generated by light winds.
Fully-developed waves generated by strong winds.
Waves that grow larger the farther they travel.
Waves moving out of the generating area.
Waves moving into shallow water and eventually breaking.
What is Swell?
Capillary waves generated by light winds.
Fully-developed waves generated by strong winds.
Waves that grow larger the farther they travel.
Waves moving out of the generating area.
Waves moving into shallow water and eventually breaking.
What is the motion of water particles as ocean waves pass by in the open ocean?
They oscillate in circles.
They oscillate in ovals.
They ride on wave crests.
They vibrate in a direction parallel to wave motion.
They vibrate in a direction perpendicular to wave motion.
At what depth do waves begin to "feel" the bottom?
1 wave height
1 wavelength
1/2 wavelength
10 meters
20 meters
What kind of waves to surfers like?
Capillary waves
Collapsing breakers
Plunging breakers
Spilling breakers
Surging breakers
Answers:
1: rip; longshore; ocean gyre (which is geostrophic, but not the unique answer); Ekman
2: upwelling; north to south; land to ocean; land breeze
3: ’72-’73, ’82-’83, ’97-’98 are major El Ninos; except for possibly ’55-’56 there are no
major La Ninas by this definition – the reasons for this asymmetry is a current topic of
research
4: cooling and heating; thermohaline; colder
5: sea arch; sea cliff; sea stack; sea cave
6: 0.4 grams of Calcium and 2 mg of Manganese (principle of constant proportions);
oxygen; At “desert” latitudes
7: Waves moving into shallow water and eventually breaking.
Waves moving out of the generating area.
They oscillate in circles
1/2 wavelength
Plunging breakers