Heath School, Brookine, MA
"Dynamics and Transport of the Antarctic Circumpolar Current in Drake Passage"
R/V Nathaniel B. Palmer
November 7 - December 7, 2007
November 7 - 8 - 14 - 15 - 16 - 18 - 19
21 - 22 - 24 - 25 - 27 - 28 - 29
December 2 - 4 - 5 - 6
November 18, 2007
Questions & Answers
56° 30' S 61° 14' W
Temp. 3.7° C/ Wind chill -0.7° C
Seas 15-18 feet and building!
Ms. O'Donnell forwarded me a bunch of questions the 8th graders had for me, so I'm going to use today's post to show the questions and my replies. Thanks for asking such great questions, and I look forward to reading more!
Alex P.: About how many people will be traveling the Drake Passage with you?
There are 7 scientists, plus about 10 people called "techs" who are well-trained people whose jobs are to help the scientists do what they need to do. They all have extensive experience at sea and/or in Antarctica so they are incredibly valuable to have with us. Also, there's a crew of about 15 people who drive the ship, keep the engines running, cook the meals etc. So all total there are a little over 30 people on board. The ship can hold up to 70, so we each get our own cabin and there are lots of empty seats in the mess hall!
Brandon, the 1st mate, driving the ship on the bridge
Alex P.: What are some of the things you'll be dropping in the ocean? What do you have to test out before you started?
I'll be writing much more at length about these next week, but basically the instruments are large instruments that are used to measure the speed and direction of ocean currents, the pressure, and salinity (salt concentration).
The equipment we are dropping into the ocean is measuring something (or several things), so the sensors need to be checked out - for example, is the current meter really measuring the speed of water accurately? Does it know which direction the water is coming from? Also, most of what we're dropping overboard will sit on the sea floor for at least a few years. The scientists want to be able to move the ship over the equipment and "talk" to it - so they need to make sure the part of the equipment that "talks" to the ship really works!
Caroline and Courtney: Will you use the instruments?
I assume you mean me, personally. Well, I'm helping to put them overboard and monitor what they are reading. On the return trip we'll travel above each one and "talk" to it and see what it's measuring. I'm also involved in a project where we're using sound signals to map the ocean floor. I'll discuss this much more next week.
Caroline, Alex S. and Tom: How much daylight will there be?
Last night sunset was about 9:00 pm, and sunrise was at 4:30. At our most southerly location, we'll have about 20 hours of daylight! Sunset will be about 10:00 pm, and sunrise will be about 3:30 am. The Sun will be just below and so close to the horizon all night that it probably won't get completely dark at all.
Caroline: Will there be animals?
We are followed by flocks of birds - mostly albatrosses and petrels. This morning we saw whales off the side of the ship!
Evan: How does the CPIES measure sound signals?
The CPIES has a "sound transducer" which can send and receive sound signals. It's like a speaker that you have in your home - If you've ever seen a speaker without its case, you'll notice that it vibrates back and forth when sound comes out of it. The "sound transducer" on the CPIES sends out a pulse (you can actually hear it!), and the reflection, or echo, of the sound travels back to it. The sound echo then makes the transducer vibrate again. That vibration is sensed by the CPIES. The CPIES then measures the time it took for the vibration to return.
Evan: How will the temperature of the water effect your results?
Great question! The temperature is a really important measurement. The oceanographers are interested in how warm and cool parts of the ocean move, so knowing the temperature at different depths gives a profile of where the warm and cool parts are in different locations in the ocean.
Sabina: How much equipment do you have to wear on a daily basis?
Depends where we are. On board the ship we wear normal casual clothes - jeans, sweatshirts or sweaters. I usually wear boots around the ship because we sometimes need to move heavy stuff around. When we go out on the upper decks of the ship, I will put on a parka because it's just a little above freezing and the wind tends to blow. When we're on the "back deck" where we deploy the instruments, there's a much greater risk of falling overboard. So we have to wear special parkas called "float coats" that have floatation devices built in.
Sabina: What do you do when you are not conducting experiments?
Each of us works a 12-hour shift each day. My shift is noon to midnight. Several times during that 12-hour shift we go out to deploy the instruments in the ocean. That process takes an hour or so. The rest of the time I am involved in helping to map the sea floor using sound waves. I'll write more about that next week, but basically we have to use a computer program to remove "bad data" from "good data" to create a good map.
Lindsay Loughry, Ariel Troisi and Linda Mills working on "ping editing," which is how we process data to make maps of the sea floor.
When I'm not "on watch," I have time to write in my blog, work out in the little gym they have here, read, or spend time watching the waves outside on the deck. I often go up to the bridge (which is where the captain and/or mates drive the ship from); the bridge has an amazing view of the ocean, and the crew don't usually mind if we go up there.
Callie: How often did "swells" occur?
"Swells" are the surface waves you see out in the ocean. When they get to shore, they break apart and form the wave shape you're used to seeing. Most surface waves are caused by the wind pushing on the water. Tonight we're feeling some swells, or waves, that are about 15-18 feet high. It's quite a ride when it's like this!
Here I'm walking down the hall trying not to fall over as the ship passes over a large swell.
Sabina: How is the terrain in Punta Arenas?
Punta Arenas is on a gently sloping plain that rises pretty quickly into some small mountains about 3,000 feet high. You can see some snow on top of some of the peaks. It's incredibly windy most of the time, so mostly you see only scraggly little trees or open fields of grass.
Sabina: Is the sunlight strong and hot?
Even though it's spring here, we are so far south that the sunlight isn't very strong. It's also been overcast most of the time we've been here.
Callie: Was Magdalena Island named after the penguins living there?
Chile, along with the rest of South America, was settled by the Spanish and Portuguese, which are Catholic countries. So the name Magdalena is Spanish for Mary Magdalene. The penguins are named after the island, which is where they nest.
Callie: Is the sun a different color?
Nope. The sun looks pretty much the same here as it does up in Boston, except that it appears to go around in a mirror image of what we see in Boston. It tends to rise in the Southeast, then move towards the North in the middle of the day, and then set in the southwest.
Courtney: How long did it take you to load the boat?
It took us about 3 days to load, stow and tie down everything on the boat, but the crew had been here for many days before us loading up a lot of other things. It also took 2 full days and many trucks of fuel to fill up the tank.
Courtney: What is the water's color?
The color of the water changes constantly and is quite beautiful. It depends on the light and the color of the sky. It's generally some combination of grays and blues, with white sparkles. I'll try to take pictures of the water under different conditions so you can see.
I'm standing with Yvonne Firing, next to the bridge, watching ~15 foot waves crash over the bow.
Courtney and Catherine: How many islands are you going to see while traveling?
We saw a few islands as we passed just South of South America. It's possible that we might see some of the Northenmost islands of Antarctica if we don't encounter too many difficulties with the equipment or if the weather stays good. I hope to see an iceberg or two, but it may be too late in the season to see them.
Catherine: Is the climate going to stay the same throughout your trip?
Well, let's distinguish between climate and weather. Climate refers to the long-term average weather. So across the Drake Passage it might get a bit colder overall. As for storms, they can happen at any time. In fact, a storm is predicted for tonight. We'll see.
Catherine: What will the ship do if it runs into a storm?
If the storm is predicted to be bad enough, then the ship would turn around or maneuver around the storm. Smaller storms aren't a problem for the ship.
Catherine: What tools are used for navigating on the ice-breaker?
I just got a tour of the bridge (like the cockpit of the ship) and got to see all their navigation equipment. It's very impressive. They use GPS (Global Positioning Satellites) and radar mostly. They have a number of radio systems to communicate with other ships in the area. They also have sonar systems that give information about the sea floor. In terms of maneuvering the ship, there are two giant propellers in the rear that move the boat forward, and a "bow thruster" in the front that allows the boat to turn in place. That's really important for a research vessel like this - often we need the boat to stay in one place while experiments are run. And in 12,000 feet of water you can't exactly drop an anchor!
Dani, Niharika and Kerry: What was in the large yellow crate?
The square crates are full of current meters and cable. The round yellow barrels hold the CPIES instruments, packed well with foam.
Niharika and Kerry: What time do you usually go to sleep?
I go to sleep a little after midnight, and get up around 8. I have lots of time to eat some breakfast, go to the little gym they have here, read or catch up on my blog.
Niharika and Kerry: Are the people you're working with nice?
Yes! Everyone on board is quite friendly and interesting. I'll be sharing some of their stories in a later post.
Niharika and Kerry: How close did you get to the penguins?
Quite close! I could have reached out and touched them if I had wanted to.
Dani: Did any penguins come up to anybody?
No, they seem pretty fearless, so we got close, but they weren't very curious about people.
Dani: What do you do to go to sleep because it will be light?
There's a cardboard shade someone made who had been in my cabin before me. So I can make the room very dark!
Jordan S. and Anthony: Is it cool to watch the water go down the drain the other way?
Actually, Jordan, toilets don't really "go down the drain the other way" in the Southern Hemisphere. When I return we can talk about this more, but that's a common myth; turns out that there is a force called the "Coriolis Force" that pulls big ocean currents to the right in the Northern Hemisphere, and to the left in the Southern Hemisphere. But the force is actually quite small - it can only be seen in large bodies of water like the ocean. You'd never be able to see that effect in a toilet bowl. In fact, my toilet at home goes "the wrong way".
Actually, the toilets on board the ship don't turn at all - it's a system that operates on vacuum, kind of like on an airplane.
Niharika, Kerry and Jordan S.: How do you know your coordinates?
We know our coordinates through a GPS on board the ship. I just learned today that the GPS system can have a small error of a few meters when you're out at sea.
Jordan S.: Was the "space problem" some sort of team building activity or was it really necessary?
This was an absolute necessity! Finding space for everything on the ship was a tricky problem. We had to figure out what equipment we would need when, and pack everything in places where it could be tied down securely (but still accessible). It took us about 3 full days to unpack, stow and tie down everything properly. We haven't yet seen much rolling from the sea, but we will. And when we do, we'll be glad we tied everything down properly!