Weeks 7 & 8: Merry Christmas and a Happy New Year
Another two weeks have flown by, Christmas has been and gone and we are on the verge of the new year.
We had the chance to fly as co-pilots in a twin otter to a BAS refuelling station in the southern part of the Antarctic Peninsula, called Fossil Bluff. I have to say that sitting next to Adam, the Pilot, in a boiler suit and wearing headphones talking into a microphone in front of many different pointers and buttons indicating pressure, location, acceleration, altitude, direction etc, is a very exciting experience!
The landscape from 9,000 feet over the Antarctic seems lunar. It is hard to tell what is what as the glaciers merge into the clouds or vice versa. At Fossil Bluff we landed with skis on snow and unloaded 5 barrels of diesel with the help of Dale, the plumber, and Ash, the marine biologist. There is a rotation between people on station to stay at this field base, mainly to report over the radio weather conditions and to load the planes with fuel.
Later on I was driven on skidoos into the station. It is a red, one roomed hut surrounded by a veranda and sheltered by a hill. The view into the mountains covered by snow in absolute silence and a brilliant sunshine was a moment to last a lifetime.
Contrasting the cold weather outdoors we found ourselves in a warm cosy 1960’s hut drinking tea by melted fresh snow. The hut consist in four beds, radio equipments, records, maps, old books, wall clocks, a collection of stones, a wooden table, a steel sink, food in tins and cans… basically, a room fulfilled by history and adventure spirit.
At Rothera, over the past couple of weeks, there have been quite a number of large icebergs creeping into the bay which at one point we thought might hinder the docking of the supply ship, the RRS (Royal Research Ship) James Clark Ross (JCR).
However, upon arrival there were only a few small icebergs in the way and the JCR majestically swept them out the way as if performing a little dance before pulling up against the wharf.
Whilst the JCR is docked there is no boating mainly because there is a massive ship in the way so there is no room to launch the boats, but also because it’s all hands on deck to unload the cargo so the JCR can leave before Christmas. Everyone lends a hand to unload the cargo for the next 12 months (food, tools, chemicals, machines, spare parts etc), especially the food by forming long human chains to take it from the container into the store room.
In total around 280 tonnes of cargo was unloaded from the JCR which also included our remaining science equipment and our Dutch colleagues Jacqueline and Maria.
Also on board of the JCR was Hoop, the final lab container! The laboratory is named after Dirck Gerritsz who commanded one of five ships which set sail from Rotterdam in 1598 to find a westward route to Asia. The lab containers are named after four of these ships, Blijde Boodschap (Annunciation), Geloof (Faith), Hoop (Hope) and Liefde (Love). The story goes that en route to Asia strong winds dispersed the fleet in the Straits of Magellan. Blijde Boodschap, commanded by Dirck Gerritsz, managed to pass the straits but was blown off course far Southwardly where mountainous land was observed at a latitude of 64o South. If so these were the South Shetland Islands and possibly the first European sighting of isles off of Antarctica!
On Christmas eve, fours days after its arrival, we waved goodbye to the JCR and made our preparations for Christmas. That evening we sipped mulled wine and ate warm mince pies.
Christmas day was a traditional British Christmas with a roast turkey dinner and all the trimmings. A full five courses later we were all totally stuffed and ready for a snooze. Complements to the Chefs, Chris, Justin and Jim, for the exquisite dinner.
At boxing day we went up the hill with the skidoos and snowboarded down hill. As the snow started to melt there are new crevasses on the way that we easily could fall into so we have to be careful driving the skidoos and stick to the marked path. We had a brilliant afternoon at Vals (the local ski hill).
The day after boxing day we managed to get out on the boat to collect some seawater. At the surface (1 m depth) the water temperature recorded with the CTD was the highest in the 14 year long dataset, as high as 4 °C. Global warming slightly raises the annual average air temperature which melts the snow and in marginally snow-covered areas the uncovered ground with a lower albedo warms the atmosphere by absorbing more heat accelerating the snow melt resulting in a positive feedback loop (also known as the ice-albedo positive feedback). Our research here will give us an insight into the effects of climate change on marine microbial communities which are also heavily influenced by the previous winters ice cover that plays a large role in regulating the mixed layer depth and so heat transfer to the lower ocean.
One of the methods we perform is called the Modified Dilution method. This is a way to estimate the rates of grazing of phytoplankton by microzooplankton (all animals smaller than 1/5 mm) and compare this to phytoplankton death due to viral lysis. Whole seawater is serially diluted with predator and/or virus-free seawater, which reduces the grazing and viral infection pressure and thus allows the phytoplankton cells that are normally lost due to grazing or viral infection to grow. Growth rates are monitored by counting the phytoplankton on the flow cytometer at the start and after 24hrs incubation, and the growth rates are then plotted versus the dilution factor to provide the loss rate (slope). The difference between the loss rates of dilutions with virus- and grazer-free water compared to dilutions with water diluted with only grazer-free seawater is the loss rate due to viral lysis. On board the JCR we had our outdoor incubator delivered which we will incubated our samples in at the actual seawater temperature and, being outside, this will also mimic the daily light cycle rather than fixed light incubations.
The dilution method is also performed alongside an experiment called Viral Production assay. This is a method to estimate the viral lysis rates of prokaryotic heterotrophs (bacteria and archaea). Whole seawater is washed free from viruses over a 0.2 µm sized membrane which retains the bacteria but allows viruses to be filtered out. After washing the sample is incubated in the dark and subsampled every 3 hours to determine the increase in virus count that are newly produced (and released from the host cell). Using fluorescent nucleic acid stains, bacteria and viruses can be counted on the flow cytometer and the production of new viruses over time divided by the number of viruses released from lysing host cells gives you the number of host cells lost due to viral lysis.
Whilst collecting water for these experiments, Ryder bay provided us with its own little Christmas gift. On the way to RaTS sampling site 1 we noticed that there was quite a lot of wild life out on the icebergs and drift ice.
A few minutes later we saw the reason why, Killer whales! All of a sudden Zoi screamed out “Tris, Orcas”. “Yea yea sure there is” I am thinking to myself as I turn around and almost pee’d my pants as an entire pod of Orcas swam right under the boat. I would say there were about 9 or 10 of them which kept on doing laps of the bay surfacing to see which icebergs had seals on them. We couldn’t believe our eyes! We were watching wildlife in action. It would be that one time that neither of us had brought our cameras out with us, damn it! Luckily for us however, another boat was out on the water and they managed to get a snap shot of us and the Orcas.
Now it is time for the New Years eve 10 km fun-run around the runway followed by a boatshed BBQ. We hope you all have had a Merry Christmas and we leave you with the link to the Rothera Research Station webcam with everyone at Rothera wishing you a Happy New Year at 00:00 GMT http://www.antarctica.ac.uk/images/webcams/rothera/index.php?cam=2&date=2013-01-01%2000:00:43&position=1