1/28/2014 – Cruise Preparations

Tasha writes: 1-P1010284 Excitement is building now that we’re almost ready to sail. By the time you read this, in fact, we’ll probably be well underway. Research time during this cruise will be split evenly between three groups: physical oceanography, seismics, and marine geology and geophysics (MG&G). Our group, the MG&G group, is comprised of the following people. Principal Investigators:

  • Chief scientist, Dr. Amy Leventer (Colgate University)
  • Dr. Amelia Shevenell and Dr. Eugene Domack (USF) 

Graduate students:

  • Michelle Guitard, Katy Smith, and Tasha Snow (USF)
  • Kelsey Winsor (OSU)

Undergraduate students:

  • Mikhaila Redovian and Kara Vadman (Colgate University)
  • David Morgan (Hamilton College)
Gene Domack shares with the students some insights gleaned from three decades of Antarctic research. Number one: Look around. This is not Antarctica.

Gene Domack shares with the students some insights gleaned from three decades of Antarctic research. Number one: Look around. This is not Antarctica.

Since our arrival in Hobart, Tasmania, we have been steadily working together to prepare the ship for the six-week research cruise. When we first stepped onto the R/V Palmer for the cruise, we found the labs completely bare; they had just been stripped down by the outgoing science crew and were ready for the incoming group of scientists to set them up in a way that best facilitates the new research demands. That would be our primary focus for the four days before the cruise.

Core lab ready for transit. The calm before the storm.

Aft dry lab ready for transit. The calm before the storm.

We began transforming the lab on Saturday, Jan 25th, by unpacking all of our supplies: sediment sampling tools, vials and bags for carrying samples, and a cornucopia of other odds and ends that together make scientific research possible. We strategically arranged lab benches to accommodate 6-meter (20ft) long jumbo kasten cores and leaving space to move around the core in the limited lab space; the process became more of a game of Tetris than lab setup.Next, we built jumbo piston core racks as well as our magnetic susceptibility (MS) system with core tracks and electronics that will be used to measure the amount of magnetic material in the cores (like magnetite). We secured all equipment and boxes for sea by bolting down all loose tables, using ropes and bungees to tie any loose items to the table legs, and fixing any drawers that do not latch properly. This will prevent drawers from ceaselessly banging open and closed, boxes sliding around the room dumping their contents, and objects becoming missiles during heavy seas.

To wrap up our preparations for the transit south, we cleaned all of the lab benches and cabinet doors for radiocarbon, first with soap and then ethanol. Cleaning will help to prevent the radiocarbon contamination of our sediment samples that would artificially alter our radiocarbon dating measurements. After being cleaned, lab benches were covered with bench paper and our facility preparations complete. Now as we set sail on our long voyage to the East Antarctic, the lab will be ready for any sort of event we might encounter. Continue reading

1/27/2014 – A Long Way Here and a Long Way to Go

Michelle writes: 

This is only my first blog post and barely my fourth day in Hobart, Tasmania, but I already feel like I left home ages ago. Perhaps this is because it took about 30 hours of traveling to get from Florida to Tasmania, or maybe because I have been busy every day. Or maybe I am finally beginning to realize how much work we have to do and the weeks are stretching out endlessly in front of me.

The Palmer still working on her tan

The Palmer still working on her tan

That sounds like I am dreading this cruise- quite the opposite! I am so excited to finally be here and have the opportunity to contribute to the understanding of changing ice dynamics in East Antarctica. I think the reason I feel so removed from what I consider “normal life” is because the cruise is really a whole different ballgame. First off, it spans 46 days. It will take 7 days just to get down to Antarctica, and then there is a solid month of work surveying and sampling the continental shelf from the George V Shelf up to the Totten and Shackleton glaciers. Second, our study area is so isolated and the elements are so extreme, it’s enough to make anyone feel slightly anxious. And third, this cruise has been in the works for many years, with many smart and experienced scientists spearheading the effort. Continue reading

1/27/2014 – Mysteries of East Antarctica’s Totten Glacier System

Amelia writes:

Well, we are almost off on our next big adventure. Here’s our very official-sounding description of what we’re going to be up to.

R/V Nathaniel B. Palmer sunning herself in Hobart

R/V Nathaniel B. Palmer sunning herself in Hobart

On January 29, 2014, two University of South Florida College of Marine Science faculty members, Dr. Eugene Domack and Dr. Amelia Shevenell, and three graduate students, Ms. Michelle Guitard, Ms. Katie Smith, and Ms. Tasha Snow, will board the United States Antarctic Program research icebreaker Nathanial B. Palmer in Hobart, Tasmania and embark on an oceanographic research expedition to the remote Totten Glacier, East Antarctica.

The USF team is part of a multidisciplinary group of earth scientists from Colgate University, Columbia University, Macquarie University, Texas A&M, University of Tasmania, University of Texas, and Geoscience Australia. The team will spend 46 days collecting oceanographic and geologic data to better understand the coupling of ocean and ice in one of the most remote and climatically sensitive regions in Antarctica.

Totten Glacier is the termination of the largest marine-based portion of the East Antarctic Ice Sheet, yet surprisingly little is known about its stability. Due its remote location and heavy sea ice, the continental shelf in front of the Totten Glacier has never been comprehensively surveyed. In fact, much more is known about the bedrock topography underneath Antarctica’s vast ice sheets than about the depth of the ocean floor in this region.

Totten subglacial

Recent satellite observations indicate that the Totten ice drainage system is thinning in response to undermelting by intruding warm ocean waters. While this process is observed elsewhere in Antarctica (e.g. the rapidly retreating Pine Island Glacier in West Antarctica), the Totten Glacier system is potentially Antarctica’s most important glacial drainage system due to its large size; it is three times larger than any system in West Antarctica. Thus, the system could transfer large volumes of glacial meltwater to the oceans at faster rates than any other marine based ice system on Earth. Continue reading

11/14/2013 – That’s a Wrap

Amelia writes: 

With my first gig as Chief Scientist behind me, I now have the time to weigh in on our cruise, the scientific successes and failures, the importance of teamwork, and the balance between hard work and fun.

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I just gave a final science talk that reviewed the scientific objectives of our cruise, and linked these objectives to the material we collected. It was really nice to see the mix of science party and technical support staff in my audience and to have to explain why what we did was important to our broader understanding of Antarctica’s climate history. Although we always dwell on what we were not able to do/collect (water column samples, sediments from basins to the south of Palmer Station), this cruise was extremely successful. Continue reading

11/9/2013 – Slow Going Through the Sea Ice

Michelle writes:

One aspect of science that I particularly enjoy is that my work never runs at the same pace. Sometimes I am frantically working 10-hour days, skipping weekends and staying up late to make a deadline. Other times I spend a few hours in my office, then head home to spend a couple leisurely hours reading papers. That seems to apply to ship work as well.  This past week has been work, work, work during our 12-hour shifts. Now, we are at a standstill… literally. Under normal conditions, the ship would have pulled into Palmer Station to transfer gear and crew and we would be busy putting stuff away and preparing for our Drake crossing back to South America. What’s stopping us? Sea ice.

"Dang it. I knew we shoulda brought the chains."

“Dang it. I knew we shoulda brought the chains.”

Sea ice is many things: a habitat, an insulator, a reflective surface (and in our case, a hindrance). It is a habitat for diatoms (tiny photosynthetic organisms) that live in the saline channels within the ice. These algae are the base of the food chain for a highly productive ecosystem. All those animals we associate with Antarctica–leopard seals, penguins, albatrosses, orcas–none of these would exist if not for the diatoms that turn that beautiful white ice to brown.

Hey, that greenish brown junk really looks like po ... tentially important scientific material!

Hey, that greenish brown junk really looks like po … tentially important scientific material!

The diatoms are important to a paleoceanographer’s line of work because they contain the clues to Antarctica’s paleo-environment (“paleo” meaning old, or ancient, especially relating to the geologic past). Like us, these organisms have a type of skin called a membrane. Their membrane is much simpler than ours, but it has a specific structure. This structure contains fats, or lipids, and there are certain lipids that are specific to the diatoms living in the sea ice. Continue reading

11/7/2013 – Best Cruise Days Yet

Michelle writes:

I know I have already mentioned the pros and cons to working the night shift. Today I wanted to focus on the great experiences I have been having on recent night shifts.

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This is a ‘con’.

Yesterday’s shift was the first time I was able to help extrude a core. Okay, I know some readers may be asking, “What is so exciting about that?” For one thing, it’s muddy, and I love playing in the mud (just ask my mom about my childhood hobbies). I also get to use some interesting tools that I would not normally handle. For example, there is a handheld tool specifically designed to cut PVC pipe by repeatedly scoring the surface of the PVC. It looks like a hook with a small pizza slicer attached. All cores are extruded on deck, which is another reason I really like this work, especially on a day like yesterday when it was bright, breezy and only slightly below freezing. I do have to put on a lot of extra gear (steel-toed boots, float coats, hard hats, leather insulated gloves), but it’s all worth it to be outside in the fresh air.

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It’s really starting to feel like summer!

It’s a big operation to deploy, retrieve and extrude these cores. Jobs include: crane operator, one person to push the PVC lining through the metal outer shell, one person to guide the core onto a stand, one person to handle sampling tools, and one other person who does the actually cutting and labeling of the core. The core I helped out with was called a jumbo gravity core, or JGC for short. Continue reading

11/7/2013 – Neck Deep in Sediment, Part 1

Tasha writes:

When you are a geologist, there is no greater happiness than when you are neck deep in the mud of a well-taken core. That’s how I’ve felt for the last couple days. Alex and I have been standing 12-hour watches together from noon to midnight each day. The science party has been working non-stop, as we have few people and a whole ton of work to do.

Alex Hare (Hamilton College) at the helm

Alex Hare (Hamilton College) at the helm

In total so far, we have taken three jumbo gravity cores, a jumbo kasten core, and three regular sized kasten cores. The gravity core differs from the kasten core in having a liner within the pipe that stays around the sediments until the core is cut open in a core repository like the one we will use at Florida State University (check my last blog to learn about kasten cores). The gravity core is round, not square like the kasten, and can go much deeper into sediments because it is heavily weighted and dropped rapidly to the bottom of the ocean. It blows past the soft upper layer of sediments usually, so we take the kasten core in the same location to get a continuous sediment record.

Amelia and Tasha get ready to inspect a fresh kasten core. Gravity core in the foreground, with till on the outer barrel.

Amelia and Tasha get ready to inspect a fresh kasten core. Gravity core in the foreground, with till on the outer barrel.

Like the kasten core, there is a trick to taking a great gravity core especially in Antarctica. Here there are layers of sediment, called glacial till. Glacial till comes directly from an ice sheet that is grinding up rocks and sediments then spitting them out from the edge of the ice sheet onto the ocean floor, creating what is called a glacial fan deposit. Glacial till can be very dense sediment and may as well be concrete to a gravity core trying to penetrate into it. If the gravity core penetrates too far into the till, the core barrel will bend as if it has hit a concrete wall. Continue reading

11/4/2013 – Start of Science

1-P1000530[Check out the Facebook page for more photos that we couldn’t squeeze into the blog entry. This link to the album will work even for those without a Facebook account.]

Michelle writes:

Last night was my first shift on watch. I walked into the electronics lab at midnight to find the day shift crew partially covered in mud. This meant they had collected and begun to process our first core: a 4.5 meter long jumbo kasten core. As far as cores go, it was well-recovered and very nice looking. Layers were clearly defined, and colors included olive green, red, black and pale green.

Dr. Amy Leventer (Colgate University) discusses sampling procedure with Christina Hubt (Tulane University) and Issy Weisman (Hamilton College)

Dr. Amy Leventer (Colgate University) discusses sampling procedure with Christina Hubt (Tulane University) and Issy Weisman (Hamilton College)

As the day crew transitioned out, we began our work sampling the core. Amelia and Amy both have different projects they are working on, so their sampling strategy requires several samples taken at select intervals. It fell to Issy, Cristina and me to sample the mud using syringes, bag them and place the samples in either the -80 C freezer or the +4 C cooler. The task was pretty simple, but we had to take close to 400 samples, so we were at it for about seven hours. Continue reading

11/3-11/4/2013 – Trials of Sea Ice and Coring

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[Check out the Facebook page for more photos that we couldn’t squeeze into the blog entry. This link to the album will work even for those without a Facebook account.]

Tasha writes:

We were at Palmer Station for almost two days. It was nice to visit the store to buy Antarctica garb, meet the Palmer occupants, and hike the glacier. Views from the top of the glacier were breathtaking: snow draped islands fringing the station; glacier scoured rock outcrops littering the island; a giant, bright blue cave leading to glacial melt under the glacier; and….large expanses of sea ice!

Blue holes are little different here than back in Florida

Blue holes are little different here than back in Florida

While at Palmer, wind blew a ton of sea ice in around our mooring and into some of the locations we planned to visit to core. This included our first stop, Palmer Deep, which is an area where an ice stream carved out a basin over 1,000 meters deep. As we soon found out, the ice would make our voyage to Palmer Deep a bit more difficult than we had hoped. Continue reading

10/25 to 10/26/2012: Last Day of Science

After sleeping for about 3 hours, I awoke to find that we were transiting to Spring Point, where we were going to attempt to install the new GPS station that we were unable to do on the way down due to fast ice. We arrived in Hugh’s Bay around 15:00 to discover that it was blowing 40 knots and there was no way to launch the small boats to bring people ashore.

Gene decided that we needed a new plan, so we designed a depth transect of pocket basins from 300-750 meters deep. At each of these sites, we would collect surface sediments using a Smith Mack Grab sampler. Then we would do a CTD to determine the temperatures of the water above the site. This information may be helpful for further developing a paleotemperature proxy for cold waters. We also left the option open to collect one or two kasten cores.

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With this new plan, my next 22-hour day began. The grab deployments are relatively easy and the sampling is even easier: a few scoops of sediment from 0-2 cm, and we are finished. Seems a shame, given it can take up to an hour of wire time. I caught a cat-nap and was awoken to deal with the second to last grab. Continue reading