2010 Expedition to Antarctica

Week 3

Monday, January 11

Today has been filled with much excitement. Helicopters took off shortly after breakfast, around 8:30 am. All those not involved with the flights took to the fifth deck for prime picture taking perches. Both helicopters performed three small test flights, one right after the other, prior to their actual flights. After both helicopters were safely off the ship, Colgate University professor Amy Leventer organized an ice sampling trip out onto the ice flow. She invited most of the day shift personnel, including myself, to participate in the sampling and to have the opportunity to stand on roughly 700 meters of water. Our measurements showed that the ice flow is about 75 cm in thickness with a three to five centimeter layer of snow on top; we also used a hand drill to collect three short ice cores to see the abundance and type of phytoplankton in the ice. All are back on board now, and based on the results from the ice reconnaissance mission and updated satellite imagery, we have decided to head to the western side of the Antarctic Peninsula, where we be in range to fly the helicopters to our target glaciological sites in the Larsen System. En route, we will be re-evaluating our marine geological, biological, and oceanographic goals. Today's helicopter missions proved to be successful as we awaited information on ice conditions. During his National Geographic-documented trip to the southern side of the Sjorgen Fjord via helicopter, Dr. Greg Balco found granite erratics on the mountainside. Additionally, Dr. Martin Truffer and Dr. Erin Pettit completed a velocity/ thickness survey of Röhss Glacier, and back on the ship, we performed water sampling at various depths with a CTD (conductivity, temperature, and depth profiler). At the close of the day, all of us went to secure our labs and personal belongings in anticipation of entering open water in the Bransfield Strait by tomorrow morning.

Tuesday, January 12

We spent today backing out of the ice and motoring through the Antarctic Sound and around to the western Antarctic Peninsula. Our transit brought us through some amazing open-water scenery. As we passed through the Bransfield Strait and into the Gerlache Strait, two playful hump back whales accompanied the ship, jumping, turning on their backs, slamming into the water over and over again. All rushed up to the bridge to say hello to our visitors. Thanks to University of Houston undergraduate student Yuribia Munoz, we have captured a picture of one of the whales to share with you. Our decision to transit to the western Antarctic Peninsula is the clear choice in how to use our time on the vessel, as the Larsen System is currently inaccessible due to ice conditions. Although glacier operations will largely remain intact with our new route, moving away from the Larsen system has required the marine geologists and biologists to re-evaluate their goals. Chief Scientist E. Domack held a meeting tonight for all of us to voice our ideas for what the marine geologist and biologists will do on the western side of the Antarctic Peninsula. As a graduate student, I am amazed at the flexibility of the principle investigators and fellow scientists on the ship. Their spirits are still high, and they are prepared to make the most of our current location.

Wednesday, Jan 13

By mid-morning, we were making our way out of the Gerlache Strait and into Flandres Bay. The three Belgians on the ship made it known to all that this area was first scouted by Belgian explorers in the early 1900s and coached us in the appropriate pronunciation of "Gerlache" and "Flandres." Today, we prepared for helicopter operations, but by mid-afternoon, our window of opportunity closed, as the clouds moved too low and inhibited the pilots' visibility. We will try again tomorrow. Although we did not get the glaciologist out on the ice, we continued with marine geology and biology operations on the ship by deploying another CTD in an arm of Flandres Bay, called Etienne Bay. We sampled the water column with the CTD at the back of the bay quite close to the ice front, where the scenery is beautiful. Our location is known to be a hotspot for whale spotting, and sure enough, two to three hump back whales came to check the ship out in the afternoon, and all rushed to snap a picture of them. Tonight also gave us the opportunity to discuss sediment coring procedures for the coming days and weeks. We have plans to use a variety of sediment sampling devices, such as the Kasten core, mega-core, sediment grabs, and the jumbo piston core. Each device is designed for different kinds of sampling procedures. For example, many of the geologists will use the Kasten core to collect sediment for radiocarbon, stable isotope, and grain size analysis as well as other tests, but Hamilton College professor Mike McCormick is keen on using the mega-core to limit the sediment's exposure to oxygen. Soon, I will offer more detail and pictures of the coring procedures as we perform them. Tomorrow, we will try helicopter operations again, and take "Suzee," the Belgian remotely operator vehicle (ROV), for a test swim.

Thursday, January 14

This morning, the weather in Flandres Bay was clear and sunny, and the prospect of getting the helicopters off the ground, one to transport Dr. Erin Pettit and Dr. Martin Truffer to the glacier and another to take Dr. Eugene Domack and Dr. Amy Leventer to a GPS station, was looking good. Helicopter pilot Barry James took a quick flight up to survey the clouds near the drop-off target on the eastern side of the Antarctic Peninsula. It was too cloudy with the limited visibility, and the helicopters were on hold until the weather cleared, which unfortunately never occurred today. When helicopter operations are halted, work on the ship continues. To take advantage of the waiting time, we continued our geological and biological survey of Flandres Bay by casting four more CTDs and dropping the yo-yo camera. The yo-yo camera's name aptly describes how it works. We strap a camera to a metal frame, send it down to about 2 m above the seafloor, and allow it to essentially hop along as we move the ship to take images of the seafloor. Dr. Craig Smith and others wanted to use the yo-yo camera to get an idea about the mega-fauna (i.e. organisms identifiable without magnification) on the seafloor to help plan further sampling goals. As I reported yesterday, the flexibility and continued enthusiasm of the principle investigators motivates us all to do what we can, and we are surely taking advantage of being in Flandres Bay! One step toward planning the rest of our science agenda for the western Antarctic Peninsula requires some background research on fjord biology. We see the opportunity to compare what we find here (in terms of geology and biology) in Flandres Bay, a more mature fjord, to what we hopefully get to study in the Larsen System, a new system that formed since the break-up of the Larsen B Ice Shelf in 2002. In order to get access to the literature, we will be dropping four scientists off at Palmer Station, a U.S. Antarctic Program base about 30 nmiles from our current position, which will take about 3 hours to reach. For the rest of the afternoon and evening, the Belgians tested the ROV with hopes to deploy it tomorrow, and Dr. Ted Scambos and company hosted a "party," complete with snacks and live guitar provided by Dr. Terry Haran, to help assemble some equipment for their fieldwork.

Friday, January 15

It seems like everyone on the ship starts his/her day with a renewed sense of enthusiasm for what the day may bring—be it taking a sediment core, getting a helicopter successfully off the ship, or sighting whales or a leopard seal. Today, we, especially the marine geologists, were looking forward to recovering a jumbo Kasten core in the Hugo Island Trough (at a water depth of about 650 m). The jumbo Kasten coring device allows us to recover up to 6 m of sediment. Unfortunately, we fell prey to bad weather again, and as in the Drake, most of us retreated to our rooms or the TV lounge to wait it out. Although the weather inhibited any device deployments, the day was not lost! In the morning (at the close of the night shift), we dropped four individuals off at Palmer Station on Anvers Island to conduct a brief literature search on fjord biology. I used the word fjord in yesterday's blog without properly defining it. Fjords are flooded valleys that were carved by glaciers. Examples of mature fjords line the coasts of Norway. We are especially interested in the relatively newly formed fjords on the eastern side in the Larsen System, Antarctica, but until we can get in there, we are making use of our time to better understand the fjords on the western side, which are more developed than on the eastern side. To drop the four researchers off, the ship pulled close enough to Palmer Station, such that a Zodiac, a small motorized air raft that we use for small transits in calm water, met the ship to pick the four up. After the drop, we left the safety of Anvers Island's shadow, and entered rough waters, stirred up by high winds. Because the jumbo Kasten core was unfeasible today, we used our time to fill in the gaps in some of our topographic coverage of the seafloor, and the ROV team worked on "Suzee." Tomorrow is another day, and we will give coring another go.

Saturday, January 16

Mud, mud, and more mud. Yes! We successfully recovered a 4.5 m jumbo Kasten core from the Hugo Island Trough. The waters were a bit calmer than yesterday, so with Chief Scientist E. Domack's urging, we made a go for the core. Observing the deployment and recovery of a sediment core, especially one of this size in these seas, was a bit like being in the peanut gallery during open heart surgery. The orchestrated frenzy started with the diagnosis; Dr. Domack and others identified the site where they wanted the core, based on seismic images of the seafloor that allow us to estimate the thickness of particular sediment units, and with the order, Captain Joe and crew positioned the ship. Next, came the preparatory work; the Raytheon marine technicians, wearing bright orange "float coats" and tethered onto the back deck, rigged the 6-m long coring device, which was loaded with over 1100 lbs of lead weights, and lowered it down with the winch. As the rest of us watched the winch monitor from the navigation table, the core streamed down to the seafloor, covering 650 m in about 20 minutes, and punched a hole in the bottom of the ocean. Caps closed, and the winch started to bring the sediment core up. When the core reached the surface, the Raytheon MTs wrangled it onboard, careful not to dip or twist the barrel. At this time, Dr. Domack and the support team met the core on the deck. Dr. Domack, swift and determined with years of experience, tapped the core and opened the first panel to view the sediment-water interface. The sediment-water interface is the division line between the water and the seafloor sediment, and if the sediment-water interface remains identifiable after the core makes it onto the back deck, the core is considered a success. Dr. Domack approved what he saw, and secured the core by placing a piece of foam at the top. Now, the tricky part. About ten of us maneuvered the long, heavy core from the back deck, through the Baltic room, and into the lab and placed it on the longest table we could rig, although the core still extended beyond the ends of the table. The sediment was now ready to be unveiled for Dr. Domack to describe the sediment and orchestrate the operation. A handful of scientists onboard collected sediment at predefined depth intervals for a slew of analyses, including cesium and radiocarbon dating, diatom and foraminifera (microscopic marine organisms) counting and identification, magnetic susceptibility, x-ray analysis, and pigment analysis. The 4.5 meters that we collected probably represents close to 12,000 years of sedimentation. Apart from the excitement and hard work associated with the recovery and processing of the core, we also deployed a yo-yo camera, and the ROV team continued to work on "Suzee." At the close of the day, we, at least Captain Joe (from Morgan City, Louisiana) and I (now living in New Orleans) were happy to hear that the Saints prevailed.

Sunday, January 17

As the night shifters and the lingering day shifters worked into the evening, we completed sampling the Hugo Trough core around 4 a.m. The recovery of the core was useful scientifically and also provided us with the opportunity to nail down our sampling routine to perfect the process for later cores. Still on the high of a successful recovery, today we turned our focus back to Flandres Bay, where we were a couple of days ago before weather chased us out of the bay. We deployed two more yo-yo cameras as well as conducted four CTD casts. The CTD casts show us (in real time) the temperature, salinity, "cloudiness," dissolved oxygen content, and chlorophyll levels in the water at different depths, from the surface to the bottom of the ocean. We also have the capability to "fire" 24 eight-liter bottles at different depths when we want to collect water samples. The program is usually controlled by Lamont Doherty graduate student Debra Tillinger during the day shift, or her mentor Bruce Huber during the night shift. Tomorrow, we will transit to the Gerlache Strait to conduct a seafloor survey to help us determine our next series of sampling operatives.

— Commentary and photos provided by Kimberly Roe '08