Office of Marine Programs
University of Rhode Island
Narragansett Bay Campus
Narragansett, RI 02882-1197
Phone: 401-874-6211
Fax: 401-874-6486
Email: OMP@gso.uri.edu
Examination of Phytoplankton Biodiversity
R/V Endeavor Cruise L
3/24/07
1700
34o09” latitude
Hello everyone!
We enjoyed clear skies with air temperature of 19.4oC at 0721. The sun is brilliant.
Our first stop in the Sargasso Sea; lat 34o09”.
At each station of the cruise, measurements are taken in the following order:
- The rosette is sent overboard to the greatest depth then at stops closer to the surface. The canisters are closed by the operator in the lab. CTD (conductivity, temperature, depth) measurements are recorded by the computer.
- When the rosette is brought back on board, Scott from SeaLabs “casts” his device from the A-frame to measure the scattering and absorption of specific wavelengths of the visible light spectrum.
- Once that equipment has finished sampling, Chris launches his buoy
- Chris takes hand-held measurements Chris’s experiments parallel those of Scott. Their equipment is different, however.
There is no multi-tasking here. For the first two steps, several people are engaged in readying the equipment, manning the winches, steadying the equipment as it is deployed. Meanwhile, communication between the deck and bride is maintained by the boson … to ensure that the ship maintains enough power to hold course into the wind or keep the winch cable plumb. Every time a piece of equipment is deployed or brought back aboard, permission must be sought by the captain or his designee on the bridge. So, only one team is actually engaged at any one time. If the sea is too rough for a particular set of measurements, that chance is gone and we move on.
The NASA scientists march to the beat of their own drum. They’re involved in taking measurements from equipment fastened to the superstructure of the ship or hand-held devices. They also take water samples gathered by the rosette, after Dr. R’s or Dr. J’s groups, but don’t get involved in deploying or boarding the hardware. They are interested in the amount and wavelengths of light that are reflected from the sea.
We are definitely in a different part of the ocean. During sampling this morning, we spotted four Portuguese Men O’ War ... Physalia physalis.
It is very remarkable to me that since we left the Newport area, we have seen only 2 ships on the open sea … the R/V Henry Bigelow and a ship that was far off our beam a couple of nights age. From the way it was lit, it may have been a tanker. That’s it!
No birds at all.
One set of vapor trails from a far-off jet yesterday.
THAT’S IT.
We might as well be on another planet.
I can only imagine how desolate the seafarers of old must have felt. I wonder if the grog rations were “enough.” They must have been bored out of their minds. At least we can keep busy and the Internet allows us to remain connected to the rest of the world.
About my “inventive” spelling. A couple of people have remarked about it. Sorry about that. It is difficult to type on a rolling vessel. Sometimes I have to send off an email quickly because when we reach a collecting station, the bridge has to maneuver the ship so the equipment sent overboard can be in the most advantageous part of the currents. Having the equipment ending up below the ship is not a good thing. It is critical that the winch cable be either plumb or at an angle away from the ship. These maneuvers can result in the ship’s antennae to satellites being off target, and we lose connectivity. I try to anticipate when this will happen, so I have to send off the email. When this happens, I don’t have the opportunity to edit/spell check. Once again, sorry about that.
Steamed littlenecks and chicken gumbo soup were among the choices we had for lunch. The chicken fajitas and vegetable rolls were tempting but I went for the gumbo & littlenecks. They were awesome.
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We’ve moved very little today; only 1 mile from this morning. Everyone is gathering great amounts of data.
Dinner this evening will be BBQ chicken or steak. The grill’s been heating up for about an hour.
We’ve seen many pieces of Sargassum today as well as several Physalia physalis (Portuguese Men-o-War). Sargassum is brown algae (seaweed) that forms great colonies in the Sargasso Sea. Some of us went “fishing” with buckets to gather samples for observation. I was able to get a “baby” P. Physalis … about 5 cm long, a very beautiful blue color. Its tentacles were just starting to develop. They couldn’t be easily seen in this image. If you Google Physalia physalis, you can learn much more about this fascinating creature. My bucket also had several pieces of Sargassum with shrimp and barnacles in it.
In his famous novel, 20,000 Leagues Under the Sea, Jules Verne opened Chapter XI with these words that are a great description of the Sargasso Sea:
That day the Nautilus crossed a singular part of the Atlantic Ocean. No one can be ignorant of the existence of a current of warm water known by the name of the Gulf Stream. After leaving the Gulf of Florida, we went in the direction of Spitzbergen. But before entering the Gulf of Mexico, about 45o of N. lat., this current divides into two arms, the principal one going towards the coast of Ireland and Norway, whilst the second bends to the south about the height of the Azores; then, touching the African shore, and describing a lengthened oval, returns to the Antilles. This second arm--it is rather a collar than an arm--surrounds with its circles of warm water that portion of the cold, quiet, immovable ocean called the Sargasso Sea, a perfect lake in the open Atlantic: it takes no less than three years for the great current to pass round it. Such was the region the Nautilus was now visiting, a perfect meadow, a close carpet of seaweed and tropical berries, so thick and so compact that the stem of a vessel could hardly tear its way through it. And Captain Nemo, not wishing to entangle his screw in this herbaceous mass, kept some yards beneath the surface of the waves. The name Sargasso comes from the Spanish word "sargazzo" which signifies kelp. This kelp, or berry-plant, is the principal formation of this immense bank. And this is the reason why these plants unite in the peaceful basin of the Atlantic. The only explanation which can be given, he says, seems to me to result from the experience known to all the world. Place in a vase some fragments of cork or other floating body, and give to the water in the vase a circular movement, the scattered fragments will unite in a group in the centre of the liquid surface, that is to say, in the part least agitated. In the phenomenon we are considering, the Atlantic is the vase, the Gulf Stream the circular current, and the Sargasso Sea the central point at which the floating bodies unite.
The “berries” mentioned by Verne are actually small air bladders that keep the Sargassum close to the surface of the water. This enables the plant to absorb the sunlight they need for photosynthesis.
Well, this “log” was longer than I had intended, but it was a day filled with wonder. So far, this expedition has exceeded my every expectation.
