Daily Journal

June 24, 2010

By David M. Lawrence

Overnight, while I was intensely unconscious, B watch ran into one of the squalls we had been seeing on radar, but other than a bit of rain and a brief change in wind direction, it didn't amount to much.

By the time A Watch relieved C Watch at 0700 hours, there wasn't much for us to do. Those on deck washed it. Two of my compatriots in the science lab caught up on data entry. I decided to do some reporting.

The slack time didn't last long, however. At 1000 hours, we will deploy a carousel and conduct a surface station and a neuston tow.

Oceanographic sampling from a sailing ship requires a lot of thought and hard work into managing the sails. This morning we were on a port tack, which means the wind is coming from our port side. We were running the four lowers (jib, fore stays'l, main stays'l, and mains'l), the JT (jib tops'l), the fisherman (a four-sided sail attached to the foremast and a stay between the fore and main masts), and the tops'l. Winds have been favorable, so we were not using the engine.

Before deploying any instruments, we have to get control of our speed. Before deploying the carousel, for example, we have to heave-to (halt forward progress), essentially setting ourselves adrift with our beam (side) to the wind.

To slow down for our deployment this morning, we struck (took down) the tops'l and JT. We squared the braces – the top and course yards on the foremast – in other words we adjusted the yards so that they were perpendicular to the long axis of the boat. Then we struck the fish (fisherman), leaving us with only the four lowers. Since we were on a port tack, the remaining sails were on the starboard side of the ship where they can catch the wind that makes us go forward.

Depending on the side we want to receive the wind during a deployment, we gybe (turn our stern through the wind so that it comes from the opposite side of the ship) once or twice to adjust the jib and stays'ls. Today we did so twice prior to conducting our sampling work. The first time we gybed from a port tack to a starboard tack and passed the stays'ls and jib to port side. We then gybed again to "back" the stays'ls and jib. (By backing a sail, we place the sail on the windward, rather than the leeward, side of the ship.) The mains'l was set on a port tack, while the rudder was hard to port.

The result of all this maneuvering is that as the wind hit the mains'l, it should swing the ship's stern (rear) around to the starboard side. The rudder would swing the stern over to the port side. Thus the backed stays'ls and jib acted as a brake and stabilizer to help keep us from heading into the wind.

The ship remained hove-to throughout our carousel deployment. For the neuston tow, the rudder was set amidships (straight) and the mains'l eased out to build our speed to two knots. Since we planned to turn to the northwest on our zigzag course back to Bermuda, we gybed again after the neuston tow to set the mains'l on a starboard tack with the rest of the sails. Those of us not otherwise engaged in reporting (in other words, everyone but myself), helped raise the JT and fish to help the ship pick up speed.

Now that we've all had some sea time, the volunteers (and student, Dylan Meyer) have been encouraged by the ship's professional crew to act as junior watch officers. Today, SEA volunteer Ellie Kane served in that role on deck. She planned all the maneuvers we executed today with the third mate, Jeremy Dann, but she was the one giving (most of) the orders. Fellow volunteer Leslie Peate took charge in the lab.

While the number of plastic bits collected in the neuston tow was rather small, we caught a larval swordfish about seven centimeters long. We also caught a tiny crab as well as a spectacular-looking pelagic nudibranch (snail), Glaucus atlanticus.

Today during class we learned about microbial ecology from volunteer Emelia DeForce. Emelia is a Ph.D. student – so, so close to finishing her dissertation – from the University of Massachusetts-Boston. Emelia researches Archaea, a group of organisms once classified with bacteria, but which is now recognized to be independent. Genetically the group is more closely related to eukaryotes (plants, animals, fungi, and algae) than to bacteria. Emelia is working with chief scientist Giora Proskurowski to study how marine microbes use, and possibly break down, plastics in the ocean. (Once we return to Bermuda, Emelia heads off to Siberia to study how climate change may affect methanogens (microbes that generate methane) in permafrost environments.) After her talk, we – well, I – took another group photo on the quarterdeck.

B Watch now has the ship. C Watch takes over for evening watch at 1900 hours, and A Watch has midwatch at 2300 hours. The work of the SSV Corwith Cramer is never done.

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To read a recent Science magazine article about marine debris in the oceans (June 18 issue, "The Dirt on Ocean Garbage Patches"), please visit the Previous SEA Research page.