Weekly Reports Polarstern

The Expedition PS113 Punta Arenas - Bremerhaven

The cruise leg PS113 coincides with the return voyage of Polarstern after finishing the Antarctic research season 2017/18. PS113 will begin 07 May 2018 in Punta Arenas, Chile, and end 11 June 2018 in Bremerhaven. An intermediate port call at Las Palmas, Canary Islands, is scheduled for 03 June for the exchange of personnel. Most of the time (ca. 9/10) allocated to PS113 will be used simply for transiting between Punta Arenas and Bremerhaven at an economically reasonable steaming speed of Polarstern.

The ship time available for scientific station work hence is very limited. Emphasis will thus be laid on research work that can be conducted en route along the transit course. This encompasses the main scientific project to be conducted during PS113, the commissioning of a new measuring system, the Triaxus towed ocean profiler of the AWI (topAWI), for which purpose Polarstern has to steam at a lower than normal transit speed.

This new towed system will allow measuring simultaneously with high temporal and spatial coverage and resolution in a quasi-synoptic manner many physical, chemical and biological variables that are relevant to identify the processes, which control phytoplankton photosynthesis and primary production, hence the uptake of CO2. Primary production also forms the basis of the marine food webs and ecosystems, which yield living resources.

Commissioning of topAWI will for inter-calibration purposes be accompanied by measurements made with proven techniques, such as hydrographic stations enhanced by vertical profiling of ocean optical properties. The latter is also aimed at the validation of ocean colour satellite sensors hence at improved remote sensing of phytoplankton concentrations. Samples taken for plankton genomics will allow for an assessment of meridional differences in plankton species diversity, which are expected to occur along with the crossing of different climatic zones during the transit. Recordings of surface waves and currents made by the WaMos-Radar will be compared with the acoustically measured current shears from topAWI.

Changes in atmospheric properties and processes underway from the southern hemisphere, which is less perturbed by human activities, and the more disturbed northern hemisphere will be revealed using advanced lidar systems and sun-photometers. Deepest down at the seafloor and in the sediments, bathymetric mapping and sub-bottom profiling will be conducted using various sonar systems installed on Polarstern.

Last but not least, fish caught before in Antarctic waters will be held live in aquaria, attended and transported to the AWI for extended physiological investigations.

PS113 - Weekly Report No. 2 | 14th-20th May (Whit Sunday) 2018

Whitsun Excursion with a Towed System

[23. May 2018] 

Since crossing the Tropic of Capricorn at 23° 26’ 05” South on Thursday this week travelling north we find ourselves, according to the astronomical definition, in the Tropics. The weather is what you would expect; water and air temperature lie between 26 and 27°C. Since we have also arrived in the zone of the SE Trade Winds there is a stiff and steady breeze and by day the sun shines from a sky with few clouds into deep blue ocean water.

PS113 - Weekly report No. 1 | 7 – 13 May 2018

Leaving Punta Arenas

[14. May 2018] 

On our arrival on 5th and 6th May the weather in Punta Arenas in Chile showed an unexpectedly pleasant side with scattered clouds, temperature just under 10°C and hardly any wind – unexpected, because here in the Southern Hemisphere it is now autumn and the climate at the southern extremity of Chile is harsh anyway. On 7th May the cruise participants were brought on board the Polarstern at anchor offshore by a harbour launch.

PS112 - Weekly report No. 5 | 22nd April – 2nd May 2018

Of Fin Whale aggregations, trace metals and the end of the expedition

[02. May 2018] 

We have now entered the last phase of our expedition. After spending a week surrounded by sea- and glacier ice south of the West Antarctic Peninsula we have arrived back at Elephant Island, where we will spend the remaining time of the expedition before heading back to Punta Arenas.

PS112 - Weekly report No. 4 | 15 - 21 April 2018

Krill, seals and humpack whales in the Weddell Sea

[23. April 2018] 

The last week, we spent in the waters around the northern tip of the Antarctic Peninsula. We have been really lucky again regarding the weather and, in addition to our scientific endeavors, spent some wonderful sunny days in the ice around Joinville Island and the Peninsula.



PS112 - Weekly report No. 3 | 8 - 14 April 2018

Salps, krill, and Elephant Island

[17. April 2018] 

The past week we have spent studying the waters around Elephant Island. Although this region is known for its harsh weather conditions we have been lucky and were able to continuously carry out our scientific experiments. The mood on board is very good and all working groups have made decent progress.