We’re off to a rough start this season! Two of our instruments are down, including our flow cytometer – annoying, but we can deal with it – and Colleen’s instrument for measuring superoxide. That’s a real problem. Colleen is only with us for five more days. When she leaves the instrument stays, but we will no longer have a skilled operator! Measuring superoxide is not trivial and I was supposed to spend a good chunk of this week learning how to do it. That’s going to be tricky with no instrument. Fortunately the instrument tech at Palmer this season is handy with a soldering iron and seems to have some ideas. We’ll see how that plays out tomorrow.
The one piece of good news this week is that the big storm last Sunday didn’t do much damage to the land-fast sea ice near Palmer Station. At least for now we can do a little science on the ice. This afternoon Jamie Collins, Nicole Couto, and I went out with the SAR team to establish a sea ice sample site near the station. Hopefully we can get a couple weeks of sampling at this site before the sea ice deteriorates.
Being able to do some science on the sea ice at Palmer Station is actually a pretty big deal and an unexpected bonus for this season. In some ways this is a very logical place to study ice. Palmer Station is the United States’ premier polar marine research station, and you can find dozens of papers describing the ecological importance of sea ice in this region. It’s been years however, since anyone was able to routinely access sea ice from the station. Considering the amount of ecological research that takes place here this actually seems a little silly; the single most important feature is virtually ignored for practical reasons. Working on ephemeral, dynamic sea ice requires a set of skills, equipment, and intrepidness that simply doesn’t exist in this day and age within the US Antarctic Program.
Our very small adventure today (on relatively thick, static ice) is reason to hope that that might eventually change. There isn’t a lot of institutional knowledge about sea ice at Palmer Station, but Station staff and management are open minded and seem eager to learn. As a further indication the Cold Regions Research and Engineering Lab recently provided new recommendations for sea ice operations at McMurdo Station, a major step toward a rational, data-based policy for traveling and working on ice (which I’ll link it I can find, too tired to search now… must fix flow cytometer…).
Hopefully we can get some good science done on the sea ice this season. In the Arctic large, under ice phytoplankton blooms are a major source of new carbon to the ecosystem. In the Antarctic blooms of algae at the ice-water interface are an essential food source for juvenile krill – adult krill being the major food source for virtually everything else down here. Getting some indication of when, where, and how often these events occur along the West Antarctic Peninsula will tell us a lot about how these ecosystems function, and what will happen to them as the ice season and range continues to decline.
We arrived at Palmer Station last Thursday morning after a particularly long trip down from Punta Arenas. Depending on the weather the trip across the Drake Passage and down the Peninsula to Anvers Island typically takes about four days. This time however, the Laurence M. Gould had science to do and a NOAA field camp to put in at Cape Shirreff on Livingston Island. This was a particularly welcome event as it gave us an opportunity to get off the boat and get a little exercise unloading 5 months of supplies for the NOAA science team.
Since arriving at Palmer Station the activity has been nonstop. In addition to lab orientations and water safety training there is the seemingly never-ending job of setting up our lab and getting instruments up and running. Yesterday evening following the weekly station meeting we did manage to go for a short ski on the glacier out behind the station. I’m glad we did because today the weather took a real turn for the worse; winds are gusting to 55 knots and strengthening. This is a real concern for us because wind strength and direction are the primary determinant of the presence and condition of sea ice in this area. As I wrote in my previous post we are hoping for sea ice to be either very solid, so we can sample from it or clear out completely, so we can get the zodiacs in the water. We’ll have to wait until the storm passes to see what conditions are like but very likely it will be neither!
We finished our work at the river transect. Now we had one more sample to collect. It was to the north where the abandoned valley is still flooded at the site of the tube well that started this idea. It is well BNGB013 along one of the transects that was done for the BanglaPIRE project. It was done along the side of a major “highway”, so will be accessible and it not far out of our way home. Alamgir had a contact in a nearby village and arranged, and rearranged a driller. We were glad to be heading back
to Dhaka. The hotel we stayed in was the best in Brahmanbaria, but it had bedbugs. In this moderate sized town, the choice of restaurants was limited.
The drillers arrived at our meeting place late. There was a fight between two villages the night before and some people were stabbed. They own a plot of land along the main road in the other village. Those villagers wanted them to swap it for land perpendicular to the road, but they refused. The land along the road is valuable for shops. The result was a fight until the police broke it up, but several people ended up injured. They came without their equipment so
they could sneak quickly through the other town. They got what they needed at the store where we met about 2 km west of the well site. I went ahead and located the exact place we wanted to sample.
Since the well had already been logged and sampled, we only needed to drill down to the sands, making sure the stratigraphy agreed. Relooking at the logs of the well, I realized that we barely had enough extension rods to make it to the sampling depth. Luckily we hit the sands with a couple of feet to spare. We
got our sample and headed for Dhaka. Of course, we hit terrible traffic and were late to dinner with other scientists from our project that just arrived from the U.S. Over dinner I learned that Kazi Matin Ahmed, one of the Dhaka University professors we work with was from a town right near our sampling. He said that growing up he would go to school by boat during the monsoon. The next day was packing up at the university and making copies of everything. We also had to pack up a number of GPS and seismic recorders that need to be returned to the U.S. for repairs. Unsalvageable was one from Madhupur that was destroyed in a fire. This trip was very successful; we achieved all our goals, although as usual, there were a lot of changes of plans on the fly. In Bangladesh, nothing goes as planned, but we always get everything
done. Bangladesh is a country of resilient people who know how to get things done.
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We planned to drill four or five tube wells across the abandoned channel and pick one for OSL dating samples. With the success of yesterday’s tube well drilling, we were optimistic that we could actually do the sampling. We met the drillers in the morning and headed to the next site. Since only two or three people are needed for logging the well, we left Céline and Basu and the rest of us headed off to do a short resistivity line near the first drill site. We scouted it during the drilling of the first well. On the way to the resistivity
site, we selected locations for three more wells. Depending on time, we will either drill two and then the sampling well or just three stratigraphic wells. Since it will be only 2 meter spacing between the electrodes, it will be quicker to set up despite less people. We are only trying to image the channel, so we don’t need a larger spacing. The site was also drier than the first two resistivity lines. We laid it out and started collecting data. My only concern was that the route was used as a path for local farmers collecting hay. I didn’t want them to knock off the electrode connections or to have them
shocked by the pulses of electricity we sent through the electrodes.
Once the line was running, I headed back to the drill site. They once again found a think mud layer over sand. They continued drilling deeper and found the silt clay that marks the boundary between the Holocene and Pleistocene, when sea level rose following the end of the last ice age. This was a bonus and confirmed that we were on line with the Lalmai anticline farther south. We shifted to the next line, a more difficult location next to a pond, but they managed. I headed back to the resistivity line and found them starting to pack up the equipment. When I went to take a look at the instrument, I found it hadn’t finished. It had run out of memory for recording line and stopped. We quickly reinstalled the electrodes that had been
pulled that we still needed. I deleted some older files that had already been downloaded and restarted acquisition. We had only lost four of 584 command lines.
By the time the second well and the resistivity line were done, it was questionable as to whether we could do the sampling well, which will take longer. The drillers going off for a lunch break settled it. We would do a third tube well today. During the drilling, the skies that had been threatening all day opened up.
The drillers and loggers got completely soaked, but kept going and we completed our five-well transect of the river valley. In the evening we compiled all the logs and discussed a sampling plan. Rather than take four samples in one well, we decided to take two, one above and one below the sand-mud transition in two different wells.
The OSL sample is over 2” wide and the wells we drilled were 1.5” wide. The driller decided it was best to drill a 1.5” well to the depth of the first sample, a few feet above the transition, and then overcore it to 3.5”. Then 3” wide PVC pipe
was lowered to keep the well from collapsing. Finally, we put the sampler on the auger rods and lowered it to the bottom of the well. We, actually people younger and stronger than me, pounded the sampler 30 cm into the bottom. Then we all had to pull up on it to get it out. The next step was to extrude the sample in its liner into a thick PVC pipe casing. The sample must be kept in the dark, so this was done inside a black plastic bag. Then the entire sample is wrapped in the black plastic bag and taped securely. The ends and outside of the sample will be discarded and only the core of the sample will be used for dating. Later, sample preparation will all have to be done in a darkroom. I helped sample on my last trip, but the was the first time I was in charge of the procedure. It went well. After the first sample, the drillers drilled to 1 ft. past the contact, overcored to the same depth, added the PVC liner and we sampled again. We
repeated everything for the second well and we had four OSL samples. We celebrated with green coconuts.