PS96 Weekly Report No. 2 | 14 till 20 December 2015

Sea water below, wind above and ice in between: “Polarstern” is thriving in the Southern Ocean waters between Bouvet Island and the Neumayer III station.

[21. December 2015] 

Just in time when the first weekly letter started its long distance, homeward bound journey - a “space odyssey” via satellite - the first tiny ice fragments appeared in the sea. One day later, and ice floes, knocked against the ship’s hull and woke up some of the “Antarctic greenhorns” sleeping in their berths (at the end of our cruise everyone on board will be missing this sound!).

Spring has arrived in Antarctica, and it takes a while before an icy area covering 18 million km2 has crumbled and left behind not more than 3 million km2 of sea-ice cover. We hope this “spring break” won’t take too long...

Meanwhile the preparations of scientific gear and instruments continue. The bottom trawl is being readied for action under the A-frame on the working deck and gets a first, brief taste of the Southern Ocean. The senses of the CTD are sharpened by fitting new sensors to it, and the bottom water sampler has to be persuaded to hold its water. A motor boat engine has a dry run on deck, and an umbilical is attached to the ROV so that live footage of seabed life can be watched from each cabin.

At “Polarstern’s” starboard side the simplest, and thus most reliable, analytical instrument of modern polar research is deployed, namely a 2-m long, wooden board covered in stripes of red and white paint. A small yellow label taped around it reveals its highly sophisticated scientific name: The “ice ruler”. The sea-ice observers on the Bridge use it as a scale bar to estimate ice-floe thickness in this otherwise dimension-less desert of ice and water. Spatial coverage of sea-ice floes and their thickness are recorded continuously and in detail, assisted by camera footage and radar measurements. And then, as expected, the sea ice becomes more widespread and thicker – you could almost walk to Neumayer. Now and then the helicopter is deployed 25 nautical miles ahead to evaluate the situation from an altitude at 1,000 ft: Where is the weak spot? On the other hand, the sea ice also protects us from Neptune’s occasional wind & wave outbursts.

And now to something completely different: Southern Ocean pets. The PC menu offers a selection of whales. Species, number, distance and position from the ship. Did it greet us by waiving with its fluke? Cameras with giant lenses are at hand to blow up stamp-sized whales visible at the horizon to their real size. Any approach is reported to the echo sounder room because the echo sounders have to be switches off as long as the gentle giants of the oceans pay us a visit. South of 60°S is the territory of the Antarctic Treaty and its strict rules for protecting the environment. And here the living scale bars are standing and lying on the floes: Penguins and seals remain “cool” when the famous research vessel is passing by – perhaps not surprising, when one takes into account the prevailing air and sea water temperatures.

 

Research equipment must have fancy names. In the cargo hold an “Iridium Snow Height Ice Beacon” is unveiled (= a buoy for long-term recording of snow heights). Coloured in white these buoys seem to be predestined to be lost – and in fact there is no need, intention or possibility to find them again. The buoys will carry out countless counts of countless snowflakes, transfer the numbers via satellite to Bremerhaven, and finally, when their ice-floe rafts have molten in the warmer waters north of 60°S, settle down onto the seabed. There they will serve as stable hard ground for grateful, sessile organisms.

Interesting were also a dozen evening talks presented this week to provide an overview over the scientific objectives of the various working groups on board. To give you at least a rough idea, we’ll start in the air and finish at the bottom – as an “appetizer”, so to speak:

A laser wants to X-ray turbulent winds sweeping snow from the continent out to the sea. The ice shelves have caught noble gasses that may reveal their big melt-down. There are lots of known unknowns and unknown knowns about sea ice – a small fleet of various buoys is hoped to clarify things. In the Southern Weddell Sea there is a trough filled with water: How much water is flowing there - and why and when? Fishes are swimming in this water as you might expect. But did you expect that these fishes call themselves “Notothenioidei“? And the microcosm just above the seabed – tiny organisms bathing in the currents look forward to meeting our scientific gear. And how much life is down there!? Who eats whom (food chain)? Which part and how much of this food comes out again, how is it recycled, and where is the construction material sourced from (nutrient exchange)? How are they called down there (taxonomy)? But with genetics, please. How can dissolved silica be utilised to build an agglomerate of spicules? From landscapes flattened by bulldozing glaciers back to the polar paradise. Life is resilient, especially here. When this life has ended, its immortal remains which are hard to digest finally settle down to the seafloor. Any takers? And all have to take a deep breath – oxygen is a main topic of ecological research. Who else lives here? Which morphology has the accommodation below the ship? And if any information is left, it will be hidden in the sediment cores.

“Alles klar?” Wait for the following weekly letters to find out why we are here. This weekly letter is sent home at a time when “Polarstern” is exclusively used in her role as an ice-breaking vessel, slowly but persistently paving her way to the ice-shelf front at Neumayer. Only three kilometres to go – but they are tricky!

Over Christmas and New Year the polar reporting service will be offline. Expect the next weekly report on the 4th of January.

 

Captain, crew, chief scientist and the scientific crewy wish all relatives and friends at home Merry Christmas and a Happy New Year (for us, White Christmas is guaranteed!).

 

Contact

Scientific Coordination

Rainer Knust
+49(471)4831-1709
Rainer Knust

Assistant

Sanne Bochert
+49(471)4831-1859
Sanne Bochert