Mocnessing
[This post written 6/23/08; position: lat -57’45”, long -43’10”; temp 0C; wind chill -14C]
We have a few questions from folks. First, Phil, that’s right. The researchers theorize that some of these icebergs were originally Antarctic glaciers, which may well contain iron-bearing material scraped from the continent. I hear you’ve got more than high temperatures at home. I hope the fires are far from Saratoga! Jbirch, trying to make us jealous, eh? Well, it won’t work. (whimper whimper) Katie, you are definitely your uncle Paul’s niece. Yesterday I asked Alana about the things sticking out of the football. Your theory is correct. They are wooden dowels intended to keep the football from bouncing or rolling off the iceberg.
[Pausing to apply Chapstick.] Boy, I sure have gone through a lot of Chapstick in the last month.
In two days, we must start our return journey if we hope to reach Punta Arenas as planned on June 30. Time is growing short, and the scientists are anxious to fit in as much work as possible in the hours remaining. But as so often happens, Mother Nature is making it something of a challenge. The rough seas have returned, which made it impossible to launch the ROV as we had planned. But we’ve still managed to pack a lot into the day.
The one-two dance of storm and sudden warmth seems to have filled the sea with those small chunks of ice called “growlers.” Someone told me they are called that because they make the captain growl when the ship hits them. I put no particular stock in this rumor; just doing my best to spread it. We saw many today. A number of them had a peculiar brown stripe, thin and very distinct. Tim Shaw managed to capture a sample of this striated ice. When I asked him about it at dinner (turkey ala king), he said the stripe is not algae, which was one possibility. It is dirt, and very porous. He thinks it might be volcanic in origin, though this is still speculation. He will need to test the samples in his lab back in the States before he can be sure. Certainly tantalizing.
We have also been moving to different locations around the iceberg in order to collect water samples. These will be used by Maria Vernet and her team as well as Vivien Peng and Nicole Middaugh for their bacteriological study. And a good deal of the water will be used by Tim Shaw and Ben Twining for their iron analyses. At midnight tonight, we’ll deploy the MOCNESS. This being one of the last times we’ll use the MOCNESS this voyage, I thought it would be fun to show a selection of the pictures I took the other morning at dawn, as the MOCNESS was retrieved after a night of harvesting. Here’s what I saw:
I should explain that MOCNESS is an acronym that stands for Multiple Opening-Closing Net Environmental Sensing System. It can best be described as a series of six nets, each of which can be opened or closed at a different depth and location. The nets are quite large — each with a mouth 10 meters in diameter. The device is towed behind the ship for some hours. On this voyage, we have usually deployed it around midnight, and retrieved it at dawn, around 7:00 a.m.
In the top pictures, you can see the rectangular black frame of the MOCNESS being drawn up from the water and set in the special brackets waiting for it on the deck. In the middle pictures, we see Ron Kaufmann’s team pulling the nets out of the water. In the bottom pictures, you can see what all the fuss is about — the “cod ends” of the nets, the bottles where the harvested sea creatures collect. The cod end bottles are emptied into buckets and then sorted in the hydrolab, a process I wrote about earlier (“Plankton and Penguins,” June 12).
Tomorrow and the next day, we’ll try for a last voyage of the Phoenix ROV, and weather permitting, Steve Rock will do one last deployment of his special sonar. We’ll do some more water sampling, maybe another MOCNESS, and a final circumnavigation of iceberg A43K for John Helly. Then it’s back to port, over the bounding main.