by OCEAN 6: Vonne (Shavonne L. Marshall ), Tina , Paul, Erik (Erik Fossum), Drew (Charles Rawls), Dianne (Dianne Mollica), Cassi (was sick)
Typically, the area has its lowest tide during a neap tide, when the moon
is new, and occurs around 3 AM in the morning and afternoon. Readings
taken from NOAA and HarborTides.com displayed tide levels that were going
out (the water-level is lowering) at the times when the boat was stopped
for measurements. At the first location, according to the predictions,
the tide should have been higher than the time of the second stop.
Data is consistent with these predictions. The tide at Wachapreague
was just 0.003-0.002 MLLW (mean lower low water) at approximately 1:30
EST (eastern standard time) and was 0.001 MLLW at approximately 3:30 EST.
This suggests that the tide was going towards low tide, which is precisely
what was supposed to be taking place. The tide readings from Wallops
Island state that low-tide on April 14th occurred at 3:24 EST and was approximately
0.06 meters MLLW, almost the exact time the boat was stationed at its second
stop. It was clearly evident that there was a very low tide when
returning to the shore because the boat was literally dragging the bottom
in the channel. This all ties into the fact that there had just been
a neap tide, in which the tides are usually lower than normal. It
makes sense that two days after a new moon the tidal forces are still expected
to be lower than usual.
Secondly the regular ocean currents are examined. (Co-ops.nos.noaa.gov/)
It was clearly evident that the waves were much more turbulent at Chico
Inlet, the offshore location. The water depth was greater (approximately
8.4 meters in depth), and the location was more out in the open sea.
The in-shore location, Cockle Creek, (www.mapserver.com)
had significantly calmer waves and less turbulence. This is most
likely because the depth was only 5.5 meters, and the boat was not out
in the open sea where waves are typically higher and free to build.
Cockle Creek had many sand bars and a lower depth. The lower depth allows
the waves to hit objects, such as the shore and the bottom, and spread
them out. In the open ocean, the waves do not touch bottom and build
in wave height, not wave length. Some similarities probably exist
in the areas of currents. Since there was not a major significance
in depth, there was probably no major difference in deep water currents.
The boat’s locations never entered the continental slope so that eliminates
the possibility of turbidity current affects. There also was probably
not much upwelling, or down welling, because that occurs where there is
a greater difference in water temperature at different depths. The
water temperature was fairly consistent and did not differ immensely from
surface to deepwater measurements.
To summarize, the tides were fairly consistent with predictions and expectations
of tide levels for the given date. They also were the same throughout
in structure or composition at the times the boat stopped to take measurements,
and also with the tidal cycle. Information on surface currents could
not be obtained, but there were some clear similarities and differences
between the wave actions at both locations.
<for
Part 1 of our Trip Report Click Here>