PS116 - Weekly Report No. 1 | 11 - 18 November 2018
Begin of the Antartic Season
RV Polarstern left Bremerhaven on 11th November with the high tide around noon. Due to extensive necessary amendments in the shipyard, the departure had been postponed by one day in comparison to the original time planning. This gave all participants the opportunity of a first quiet day on board to get familiar with the ship.
In total, 43 crew, 45 scientific and technical staff as well as two meteorologists from Germany's National Meteorological Service embarked in Bremerhaven. After the usual introduction to the ship’s rules and a safety training, the working groups started to settle in the laboratories and set-up their equipment. We have two lab containers with us, located on the upper decks for physical and chemical atmospheric analysis (TROPOS Leipzig and Universities of Göttingen and Hannover). A myon detector from DESY Zeuthen is set up to trace particles which origin from cosmic radiation when entering the earth’s atmosphere. Two biologists are collecting plankton for DNA determination and classification (AWI and University of Oviedo).
These projects will be presented in more detail in the upcoming weekly reports. Furthermore, a group from AWI IT department is busy with updating the ship’s server systems and getting them ready for the drift experiment MOSAiC which will start in autumn 2019. Providing data and analysis services is one part of the task.
Our leg was documented by a film team and their 360° 3D camera. Some of the shooting will become part of an exhibition at the Deutsche Schiffahrtsmuseum, Bremerhaven, in spring 2019.
The largest group on this transect are the participants from the “Echosounding Training”, organized by Helmholtz Graduate School for Polar and Marine Research POLMAR. In total, 22 young scientists (Master students and doctoral candidates) are being trained by five colleagues from AWI geosciences department to operate the echosounding systems Hydrosweep and Parasound (Fig. 1). After an in-depth introduction to the systems by Frank Niessen, watches have been set up 24/7 under the responsibility of the students.
By sending out echosounds, the acquired information goes well beyond receiving a depth determination at the ship’s actual position. The Hydrosweep system brings to life a high-resolution picture of a hidden world at the sea floor: huge dunes at the bottom of the English Channel, steep incised canyons off the coast of Portugal and submarine landslides on the slopes of the Canary Islands. The sediment echosounding system Parasound allows for a better insight into the deposits at the bottom of the ocean. Geometrical patterns of lateral deposits are suddenly in disorder, caused by landslides. The trained geologist combines the gathered information into a tale from the past: who would think that hundreds of thousands of years ago, a giant cataract plunged from the shallow North Sea shelf into the deeps of the English Channel? The remnants of this event can still be traced in the sediment. Next to their watches, the students were busy with literature research, interpretation, discussion and putting their findings into a larger geological context. One example is displayed in Figure 2: Multibeam echosounding data of marine dunes in the Strait of Dover. The view is from the English coast towards France. The asymmetric shape that dunes develop along the current is clearly visible. During the displayed record, we crossed a reversion line from south-westwards to north-east directed mean currents.
On four stations, plankton samples were taken with the handnet for further analysis. Water profiles of temperature and salinity were recorded for a proper calibration of the echosounding systems.
After rather calm weather all the way down to the Bay of Biskaye, we are now facing roughers seas and an overcast sky accompanied by light rain showers while approaching the Canaries.
All cruise participants are doing fine and look forward either to return to friends and family or to some more weeks of successful research on board. In total, 36 passengers will disembark in Las Palmas and seven new colleagues will join the vessel on its way south to Cape Town.
Greetings from all on board,