By dawn, we were steaming through the channel that separates the southern tip of South America (Argentine side of Tierra del Fuego) and Staten Island (Isla de los Estados). This route Estrecho de le Maire, although still quite open ocean we can see land on both sides, but the channel is about 15 kilometers wide gives us some leeward protection and somewhat calmer seas. We are in Argentine waters, and so the flag of Argentina is highest on our mainmast. (Do you know whose flag flies highest when we get close to Antarctica?) [Insert Photo 1]
Today begins a series of XBT drops as we cross the Drake. In a regular, timed pattern, a measuring device called an XBT (expendable bathythermograph) is being used to measure the temperature of the water through the water column (top to bottom). From my Journal writings of a previous trip south, I will use the explanation given by WHOI scientist/engineer Sandy Williams:
“The expendable bathythermograph or XBT is a probe that looks like a small (about 3 inch by 16 inch) fireworks tube used for taking the temperature of the ocean. It not only measures the temperature of the water at the surface but takes the temperature all the way down to 800 meters or more by falling through the water while spinning out a two-conductor wire and sending the signal from its thermistor back to the ship. The ship is still steaming at nearly 10 knots so it too needs to spin out a wire to the place where the XBT fell into the water. So there are actually two coils of very fine wire in an XBT, one in the probe and the other in the launcher on the ship. Eventually one or the other spool is emptied and the wire breaks, ending the profile. A section of profiles is useful to know when the ship has crossed a front and can expect to find different animals in the water. A graphic profile is made every tenth degree of latitude and a computer program will contour these measurements and color them. The section (to be sent in a future dispatch) is arranged as though you are looking from the Atlantic into the Pacific with Antarctica to the left. We’ll be able to see how the water is really in layers according to temperature and density. Something to look forward to, eh?
The weather prevents this from being very long today. The decks are closed off due to wind and waves, but through the windows, the ocean is awesome!! Waves at minimum 18-20 feet with an occasional 2 or 3 much bigger, and 40 knot winds gusting to 70. It’s so big, it all looks like slow motion. And the ship lifts up, tips one way, then the other, and goes back down again it’s all we can do just to keep chairs and other things from moving, so we’re being very diligent about tying down all of the equipment in the labs. I’m sorry to say the plankton lab lost a can of Pringles to the mighty forces of the sea but otherwise all is well. No science today, except for the XBT’s (since they’re mostly automatic). People do have to go out occasionally to reload the launcher, with due caution.
So, don't hesitate to email
questions to us at outreach@lmg.usap.gov
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Longitude/Latitude:
11:30 am: S55° 06.939’ W64° 57.335’
4:30 pm:
S55° 47.612’ W64° 43.508’
Temperature:
11:30 am: Wind: 22kn
Air Temp: 6.9°C Wind Chill: -6.8°C
4:30 pm: Wind: 47.9kn (gusting to 60)
Waves: 18-21 ft
Air Temp: 3.6°C Wind Chill: -14°C
Menu:
Chicken parmesan, veg lasagna, spaghetti & meatballs, br. sprouts, broccoli, garlic bread, fruit, salad, cake and cookies. I’m not coming back to tell you what’s for dinner
Photos:
Actual location of LMG after passing through the Strait de le Maire
Last sight of land, Tierra del Fuego, as we enter the Drake Passage
While Dan and Max load XBT launcher, Steve Rupp fires up the bar-by (We’ll be dropping him off at Palmer Station….)
A still photo from the Bridge just doesn’t tell the story
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