News from the CSD
A short report about our last stay at the AWIPEV station in August and September 2019 published on the Intaros website.
15.-20.09.19: Vorbereitungen für Expedition in den Comau Fjord (Chile)
Im Laufe der vergangenen Woche hat sich auf Helgoland ein neues Tauchteam formiert und sich auf die kommende Expedition in den Comau Fjord in Chile im Rahmen des Strategiefondprojektes „DACCOR“ vorbereitet. Vier geprüfte Forschungstaucher (Christoph Held, Gernot Nehrke, Kristina Beck, Adrian Gruhn) gewöhnten sich an die Ausrüstung für die kommende Expedition im Oktober 2019. Im Vorhafen von Helgoland auf dem „Taucherponton“ wurden u.a. wissenschaftliche Aufgaben simuliert die unter Wasser erprobt wurden und es wurden Notfallszenarien durchgespielt, um das Tauchteam auf Herz und Nieren zu testen. Die Tauchgruppe lernte u.a. die Vorteile einer durchgehenden kabelgebundenen Sprechverbindung bei wissenschaftlichen Taucheinsätzen zu schätzen und bereitete sich anhand einer detaillierten Gefährdungsbeurteilung intensiv auf die geplanten Unterwasserarbeiten im Chile vor. Am Ende der Woche kann sich ein gut ausgerüsteter und beherzter Tauchtrupp Richtung Patagonien aufmachen und auf viele erfolgreiche Tauchgänge freuen. Die Leitung des AWI Tauchzentrums wünscht der Gruppe viel Erfolg und eine gesunde Rückkehr.
21.10.-11.11.18: Successful ending of Arctic dive season 2018 at AWIPEV
The last dive mission of the season 2018 at AWIPEV in Kongsfjorden (Svalbard) started with a very special beginning. Due to bad weather conditions the AWI dive team had an alternative arrival by the help of “MS Polarsyssel”, the Sysselmannen’s (Governeur of Svalbard) service vessel, specialised on Arctic rescue operations, environmental monitoring and prevention of oil pollution.
Thanks to the logistic engineer of the AWIPEV station, who prepared the required equipment, dive operations could begin right away. General tasks for the last dive mission of this year were check, maintenance and cleaning of the existing Underwater Observatory close to
Ny-Ålesund, which also includes the land based FerryBox (4H-Jena engineering).
Weather conditions during the stay were quite well with low wind and a water temperature of 2.5 °C. However, the sun did not come above the horizon anymore and the twilight was reduced by one hour every day, so the dive team soon had to use torches for diving. Altogether diving operations went quite well. Fortunately, the newly installed underwater fundament (see dive mission report from 09.04.-30.04.2018) was still located the way as it was left behind. The profiling stereo camera system (RemOS1) was removed temporary outside the water to clean it, do some maintenance at the system and replace the lifting straps by swimming ones. Furthermore, one pump at the basement of the underwater unit had to be changed due to low pump capacity.
Additionally involved in this expedition was Steffen Assmann, Samir Alliouane and Uwe Posner as the “land team”. Steffen Assmann from Kongsberg Maritime brought a new total alkalinity Analyser (CONTROS HydroFIA® TA), which was successfully installed in the FerryBox container. The FerryBox developed by 4H-Jena is an autonomous measuring system, which measures physical and biogeochemical parameters by different sensors. This system was maintained by Uwe Posner. Samir Alliouane (French National Centre for Scientific Research (CNRS)), who is monitoring the carbonate chemistry at the AWIPEV underwater observatory, worked together with Steffen Assmann at the TA Analyser.
National Geographic: Welcome to the world's northernmost science lab
Neues Langzeitprojekt 2018 – 2019: Untersuchungen zum Biofouling und zur Korrosion von Materia-lien im Seewasser um Helgoland (IFAM – Fraunhofer-Institut für Fertigungstechnik und Angewandte Materialforschung)
Biofouling, die unerwünschte Besiedlung von Oberflächen durch Bakterien, Tiere und Pflanzen im wässrigen Milieu, ist eine große Herausforderung für industrielle Anwendungen, insbesondere für die Schifffahrt, da bereits geringer Aufwuchs zu erhöhtem Treibstoffverbrauch und höheren Emissionen führt. Aber auch in der Aquakultur ist Biofouling an Netzen und Käfigstrukturen ein großes Problem. Die Entwicklung von biozidfreien Bewuchsschutzbeschichtungen ist daher von großem wissenschaftlichem und wirtschaftlichem Interesse. In Kooperation mit dem Tauchzentrum des AWI führt das Fraunhofer IFAM statische Bewuchstests an neuartigen umweltfreundlichen Bewuchsschutzbeschichtungen durch, die einen wesentlichen Bestandteil der Entwicklungsarbeit ausmachen.
Neben den biologischen Einflüssen sind Materialien im marinen Umfeld massiven kombinierten Lasten ausgesetzt. Zur Trennung empfindlicher Metalloberflächen vom korrosiven Medium kommen Beschichtungen zur Anwendung. Um das Materialverhalten in einem natürlichen Lastkollektiv ermitteln zu können werden Proben im Prüfstand an der Helgoländer Westmole ausgelagert.
Die Oberflächen von Materialien oder Komponenten, können geeignet sein um im Meerwasser jahrelang ihre Funktion zu erfüllen und werden im Labor bezüglich ihrer Seewasserbeständigkeit geprüft. Verändert sich zum Beispiel der pH-Wert an der Grenzfläche aufgrund von mariner Besiedelung oder es kommt eine Anreicherung von kritischer Verbindungen hinzu, kann es zu gravierendem Korrosionserscheinungen kommen, mit einem schnellen Funktionsausfall des Bauteils.
Von Tim Heusinger von Waldegge
12.05.08 to 30.05.2018: Research stay of MPI Bremen and AWI Bremerhaven at the AWI CSD Helgoland to test new sensor technology for pCO2 measurements.
By Dirk Koopmans: We use special techniques to measure benthic community metabolism in situ. Interesting subjects for research include the seafloor, seagrass meadows, kelp fields, and coral reefs. The common method for benthic community metabolism is to use chambers. These are not suitable for large and complex structured ecosystems, as the whole community needs to be isolated. Moreover, benthic chambers disturb the flow regime and accumulate the products of metabolism, altering metabolic rates.
Instead, we use a non-invasive method called eddy covariance to measure dynamics in the metabolism of entire marine ecosystems. Turbulence is the dominant mechanism responsible for mixing dissolved gases in seawater. For example, when benthic microalgae photosynthesize, oxygen is transported upwards in the water column by turbulent mixing. For eddy covariance, we position a water velocity sensor and an oxygen sensor with a fast response (< 0.5 s) at the same point above the habitat of interest to record turbulent variations at high frequencies (5 Hz). Oxygen production is calculated from small changes in vertical velocity and oxygen concentration. Instead of oxygen, we can also measure metabolic activity from CO2 fluxes by measuring subtle pH changes and relating these to turbulent eddies.
Engineers and scientists at MPI and AWI (Section Bentho-Pelagic Processes) have developed electronic pH sensors and succeeded to design an accurate system based on this principle. This technique can be used to answer many ecological questions on how environmental parameters control ecosystem metabolism. Over time, oxygen production will respond to changes in irradiance, water temperature, water velocity, pH, and other parameters. Also, from discrepancies between oxygen and CO2 fluxes we can assess non-biological CO2 release, e.g. by seepage or volcanism.
To improve these pH measurements we also investigated the performance of new materials for optical pH sensing. These sensors were recently developed in TU Graz and are expected to be highly promising for long-term pH monitoring in seawater due to higher brightness and lower complexity compared to the previous prototypes. The sensors (Fig. 3) performed very well during a 3-day test outside the diver’s facility. They sensors were able to resolve the pH fluctuations smaller than 0.005 pH units.
Together, we are collaborating with Philipp Fischer at the AWI Centre for Scientific Diving to use this new technology to examine the metabolism of marine sediments at Helgoland.
Dirk Koopmans, Volker Meyer, and Dirk de Beer (Max Planck Institute for Marine Microbiology)
Moritz Holtappels (Alfred Wegener Institute)
Sergey Borisov and Birgit Ungerböck (Graz University of Technology)
09.04.2018 – 30.04.2018: A new underwater fundament for the AWIPEV Underwater Observatory on Svalbard.
After 6 years of continuous operation in 14 m water depth in Kongsfjorden (79° N), Svalbard, the worlds northernmost cabled Underwater Observatory close to Ny Ålesund had its first major revision. Since the installation of the node system in 2012 with a standard set of sensors, the system continuously “grew” in terms of additional instruments, loggers and sensors which were attached in cooperation with a growing number of national and international cooperation partners. During this time, however, the underwater observatory was subject to severe threats and survived at least 4 major iceberg collisions which partly caused significant even though not fatal damages. Therefore, during the last years, the repair of winterly ice-damage, regular maintenance and the setup of new components became a frequent task of the AWI dive-group during their expeditions to Svalbard. Nevertheless, even good maintenance and fast damage-repair procedures could not prevent the system from the destructive long-term impact of saltwater, cold temperatures, storms, sea-ice and icebergs for almost 6 years. Meanwhile some steel components were more or less gone due to corrosion, attachments were bend or even disappeared and even the heavy (400kg) concrete blocks which served as fundaments for the entire setup were displaced or just tipped over by iceberg collisions. So, during the last dive-mission in August 2017, we decided to do a substantial overhaul of the underwater part of the installation, including the replacement of the concrete fundament.
The April dive-expedition 2018 to Svalbard was therefore dedicated almost exclusively to the renewal of the Underwater Observatory. In a first step, the entire underwater installation including most sensors were removed. Then, the old concrete-blocks serving as fundament were displaced with lift-bags to an area outside with the idea to act as a kind of ice-berg shields in future. After everything was prepared and the place for the new fundament was “clean and tidy”, a new fundament construction, delivered in parts to Ny Ålesund already in winter 2017/18 was installed by the AWI divers. First, a solid steel frame of about 600 kg was placed with large lift-bags precisely on previously prepared concrete plates on the bottom and was then fixed with long (1m) steel rods hammered into the sediment. Then, the divers filled the steel frame with additional 72 concrete plates each of it with a weight if 18,4 kg so that the desired final weight of the entire construction of 1.8 tons was reached.
The next step was the reinstallation of all instruments on new base-plates mounted on the top side of the steel frame in normed holes. All instruments and sensors of the Underwater Observatory found a new place on the fundament. The new construction makes it now much easier to add or exchange system components since new parts can be already prepared to the normed holes on the base plate and then can be easily mounted under water. After 30 dives all work was done under water and all tests were successfully completed. Therefore, the Svalbard Underwater Observatory is now prepared for the next years of continuous operation under the often harsh arctic conditions.
Almost to the end of the stay, another midlife conversion happened on site. The KingsBay / AWI decompression-chamber was overhauled on site by two specialists from a Norwegian company for decompression chambers. This renewal was done in close cooperation between KingsBay, AWI and the Norwegian company so that the major safety backbone for scientific diving at AWIPEV station is now also ready to provide the required safety standards for professional scientific work under water in the Kongsfjorden ecosystem for the next years.
Max Schwanitz, May 2018
02-03.11.2017: 10th International KFT-Symposium for Scientific Diving at AWI from 02. - 03.11.2017
The 10th International KFT-Symposium "Scientific Diving in Germany, Europe and Beyond" take place from 02.11.17 to 03.11.17 in Bremerhaven at AWI (House D). The symposium is collaboratively organised by the Alfred-Wegener-Institute Helmholtz Centre of Polar and Marine Research (AWI/Bremerhaven), the Leibniz Centre for Tropical Marine Research (ZMT/Bremen) and the Deutsches Schiffahrtsmuseum (DSM/Bremerhaven). As in previous years, the symposium serves as platform for researchers which use scientific diving for their recent work, to get together to network and to establish new professional contacts.
The 2-day event starts with an Evening-Icebreaker at the 1st Nov. 2017 19:00 hours at the "Deutsches Schiffahrtsmuseum".
For details and late registration please see http://www.forschungstauchen-deutschland.de/.
13.09.2017: Three successful AWI dive-missions on Svalbard 2017
As in 2016, the AWI dive-group conducted in 2017 three dive-missions to Kongsfjord / Svalbard. The main scope of these missions was to finish the polar winter experiments installed in September / October 2016 and to maintain the Spitsbergen Underwater Observatory (https://www.awi.de/en/science/biosciences/shelf-sea-system-ecology/main-research-focus/cosyna/underwater-node-spitsbergen.html). The observatory is now in its 5th year of operation and provides year-round biological and oceanographic data from the shallow area of Kongsfjord close to Ny Ålesund. Because the observatory is installed in about 10 m water depth, all components are permanently exposed to the rough arctic underwater conditions including drift ice and icebergs and must be maintained twice a year in spring (after the winter) and in autumn (before the next winter).
The first dive mission in 2017 started in January with the tasks to maintain and calibrate some of the observatory’s underwater installations, to inspect the biological winter-setups, to sampling macroalgae and to recovery some longer-time exposed samples. During this mission, the dive group was faced with extreme outside temperatures with up to -25°C without and -40°C with wind-chill factor in combination with 24 hrs. darkness. A challenge during the first days of diving operations was therefore to develop procedures to avoid freezing of regulators and other diving equipment and to design a work schedule which ensured that none of the crew in the open boat was exposed too long to this really cold conditions. After some modifications in equipment and procedures everything worked well, the algae sampling went fine and even despite the permanent darkness some long-time exposed samples were relocated and recovered. After a few days on site, the air temperatures increased dramatically and heavy rainfall started. This resulted in a thick ice crust all over Ny Ålesund making walking on the road the most problematic action during the daily life. After all, this first mission could be finished safely until mid of February.
Only about four weeks later, mid of March 2017 the second dive-mission was scheduled. Meanwhile the daylight was back on 79°N but, unfortunately the cold - this time in combination with strong wind - was still omnipresent. Temporarily the temperatures again decreased to -44°C (with wind-chill factor) and the divers had to apply again the “anti-freezing-procedures”. This time the mission was focused more on biological projects incl. sampling of several long-time underwater set-ups (installed September / October 2016) and the collection of different algae-species from different sites and depths for a project of Spanish colleagues. Furthermore, sediment cores had to be taken and some minor repairs on the underwater observatory were conducted. Unfortunately, it turned out that one of the biological winter-experiments, which was installed in September 2016, did not survive the winter at all. Ice drift destroyed the experimental field in 9 m water-depth almost completely. The experimental set-up therefore had to be reinstalled. Fortunately all other experiments went well over the winter and the dive team finished all tasks of the second stay in time.
The third and last stay in 2017 was scheduled for August 2017 for biological projects and the winter preparation of the observatory. This time, the dive group was faced with almost summerly weather conditions. The temperatures stayed most of the time above zero and the wind speed was acceptable for diving during most of the time. The challenge during this stay was therefore not the weather but mostly the coordination of the sampling because almost all projects needed their samples at the same time. Furthermore, some more in situ experiments were scheduled which took time for a thorough coordination and several dives. Parallel to the diving, a general inspection and technical check of the decompression chamber were scheduled. Even though this was well organized by KingsBay, the AWI-divers were asked as consultants to ensure that all work would be done properly fitting in the scientific diver’s safety concept on site.
After all this work done over the year 2017, the AWI dive group left Ny Ålesund end of August for the last time in 2017 with the good feeling that all scheduled tasks were done and that the arctic winter 2017/2018 can come…
Max Schwanitz, September 2017
Stopover of our time-travel into the future ocean to investigate the growth of cold-water corals
Ocean acidification affects calcifying species, particularly those living at or near the saturation stage of the mineral (aragonite) necessary to build their skeletons. In July/August 2017 a team of scientists from AWI, University Austral de Chile and the Huinay Field Station carried out a winter expedition to Comau Fjord to terminate the one-year in situ coral-growth experiment (see former reports). The corals, previously attached to holders, were brought in water tight suitcases to the laboratory in order to analyse effects of acidified water on the growth of the test corals. Furthermore, our scientific divers retrieved temperature loggers and again took water samples close to the coral banks to determine the aragonite saturation state.
As coral growth under unfavourable environmental conditions (lower pH-values of the seawater) demands an increased amount of energy, we hypothesize that a good food supply is necessary. In order to measure food particle and oxygen fluxes towards the coral banks the AWI scientific divers installed a lander with a measuring unit, which allows to apply the Eddy Covariance (EC) technique. This method allows to measure the exchange rates 50 cm above the benthic community and combines the measurements of flow velocity and concentration of substances at high frequencies from which the flux can be calculated. We targeted the benthic oxygen fluxes, because it is a reliable proxy for benthic carbon turnover. At four dive sites the benthic oxygen respiration of cold-water corals and their associated communities as well as the one of reference areas lacking corals and the production from benthic algae was measured over day-night cycles to determine the net oxygen flux and thus the autotrophic-heterotrophic balance of the benthic ecosystem.
The data of this expedition will be analysed during the following months in Bremerhaven. This was a complementary expedition in the frame of our time-travel into the future ocean with conditions predicted by the recent IPCC report for the oceans at the end of the century. It was the last trip within the third-part project (BMBF and CONICYT) "Plankton- And cold-water Coral ecology in the Comau fjord (PACOC)", which involved observational and experimental studies on the ecology of the coldwater coral Desmophyllum dianthus and its ability to cope with global CO2 rise. However, we may call it "stopover" as there are still several questions to be answered during future projects conducted in the Chilean Patagonian Fjord Region.
30.06.2017: AWI Scientific divers investigated the growth of cold-water corals in a naturally acidified Patagonian fjord.
In May 2017 a research team of AWI, University Austral de Chile and the Huinay Field Station carried out an expedition to Comau Fjord. Previously test corals of the species Desmophyllum dianthus had been chiselled from the vertical rock faces by scientific divers and brought to the laboratory, where they had been glued on plastic screws, labelled, photographed and stained. Furthermore the mass had been determined with a fine balance. The corals were attached on holders, produced in the AWI workshop and installed in the sampling depth (20m). In order to analyse the possible influence of acidified conditions on growth, test corals were cross-transplanted within seven stations along the natural pH-gradient of the fjord. In order to have a control, some corals were installed at the place of origin.
During the present austral autumn expedition (after six months of exposure) test corals were de-attached and analysed for growth in the laboratory before they had been re-installed at the sites. Furthermore scientific divers exchanged temperature loggers and took water samples close to the corals in order to reveal the aragonite saturation state through analyses in the laboratory. In order to describe the food supply and feeding impact by the corals, plankton nets were operated by the diving scientists along a horizontal transect close to the coral wall and two meters off the wall. Plankton was not only collected by AWI-divers, but also by blue whales (Balaenoptera musculus). The expedition team saw them regularly passing by at the working sites, sometimes as close as 50m. The data is currently analysed in Bremerhaven. The team is looking forward to the next expedition, taking place in austral winter 2017.
12.05.2017: The darkness vanished – the cold stayed: 2nd part of the 2017 AWI Spitzbergen Dive Mission 2017.
Even though the AWI dive-team was expecting low temperatures and snowfall when arriving for the second stay in Ny Ålesund on March 13th, there was a slight hope for weather improvement in early spring. Unfortunately, this improvement didn’t show up and Ny Ålesund faced a snow blizzard when the team tried to reach the station so that even some flight from Longyearbyen to NyAlesund had to be cancelled.
Anyway, the daylight was back and it was possible to work without artificial light both in the boat and also under water - even though the weather conditions were far from announcing the upcoming spring. The first check dives were therefore done in a sheltered place within the harbor and it turned out that both, equipment and divers needed special procedures when working at wind-chill temperatures of -30°C and below. The next days did not bring any improvement and temporarily the strong wind decreased the temperatures down to -44°C when considering the wind-chill factor. After adapting the diving procedure and the time-schedule to this pure arctic condition, the divers started to support four different AWI-projects on site.
During the next two weeks, the main tasks for the dive group comprised the collection of different species of fresh algae, taking sediment cores, maintaining parts of the AWIPEV underwater observatory and collecting samples for some other long-time in situ experiments. Most of the scheduled jobs went very well but others did not. One in situ setups which was installed in September 2016 did not survive the harsh winter conditions with icebergs and was more or less completely destroyed. For this experiment a substitute could be successfully installed. Even though the weather did not improve during the second stay of the AWI dive group at NyAlesund, at the end of the mission, almost all underwater work was successfully done and everybody was quite satisfied and happy that things worked out well under these conditions anyway. We are now looking forward to the third dive mission at NyAlesund in August when a full program is waiting for the group again.
Max Schwanitz, May 2017
02.04.017: AWI Scientific divers investigated the growth of cold-water corals in a naturally acidified Patagonian fjord.
The rising CO2 levels in the atmosphere are predicted to change seawater chemistry and lower the aragonite saturation state, with negative consequences particularly for animals building up calcium carbonate skeletons such as cold-water corals. The Chilean Fjord Comau offers a unique natural laboratory, with conditions from aragonite-supersaturated waters near the surface to under saturated waters at depth. Our research revealed that the cold-water coral Desmophyllum dianthus even thrives below the aragonite saturation horizon, indicating an adaptation to acidified conditions. Because coral growth demands energy, we hypothesize that a good food supply provides the energy to maintain growth in acidified waters (lower pH-values of the seawater).
The third-part project (BMBF and CONICYT) “Plankton- And cold-water COral ecology in the Comau fjord (PACOC)” involves observational and experimental studies on the ecology of the cold-water coral Desmophyllum dianthus and ability to cope with global CO2 rise. In January/February 2017 a research team of AWI, University Austral de Chile and the Huinay Field Station carried out an expedition to Comau Fjord.
Previously test corals of the species Desmophyllum dianthus had been chiselled from the vertical rock faces by scientific divers and brought to the laboratory, where they had been glued on plastic screws, labelled, photographed and stained. Furthermore the mass had been determined with a fine balance. The corals were attached on hand made coral holders, produced in the AWI workshop and installed in the sampling depth (20m). In order to analyse the possible influence of acidified conditions on growth, test corals were cross-transplanted within the seven stations along the natural pH-gradient of the fjord. In order to have a control some corals were installed at the place of origin.
During the present austral summer expedition (after three months of exposure) test corals were de-attached and analysed for growth in the laboratory before they had been re-installed at the sites again. Furthermore the diving scientists exchanged temperature loggers. In order to describe the food supply and feeding impact by the corals, plankton nets were operated by scientific divers along a horizontal transect close to the coral wall and two meters off the wall. The data is currently analysed in Bremerhaven. The team is looking forward to the next expedition, taking place in austral autumn 2017.
14.02.2017: Ny-Ålesund dive season 2017 successfully opened.
The AWI opened its research diving season 2017 at the polar research station Ny Ålesund by arrival of the scientific diving team on the 27.01.2017. Five different projects were scheduled for this first expedition. For three “macro algae” projects (KOL-06), fresh algae and long term exposure samples had to be recovered and the status of underwater long term experiments had to be checked and photographically documented. Furthermore, the status of the AWIPEV underwater observatory had to be assessed after an iceberg hit the system at the 15. Jan. 2017 - and in case of damage - the respective repair works should be performed under water. Besides, routine maintenance and calibration procedures were scheduled for the AWIPEV-FerryBox, which is part of the underwater observatory project KOL07.
The first days started in truly arctic conditions. -25°C (-40° with wind chill factor) made diving very challenging with respect to freezing equipment on the boat and the human factor, when staying more than 2h outside outsind on the water. After one week, the temperatures increased to unexpected positive degrees and intense rainfall started. This turned all roads and places in Ny-Ålesund into an almost perfect skating rink and stopped all regular flight movements from and to Longyearbyen for almost one week. Parts of the scientific crew therefore arrived by helicopter while others left Ny-Ålesund, other collegues could not arrive at all.
Nevertheless, all samplings were performed as scheduled and the maintenance work under water could be finished successfully within a total of 18 “night”-dives.
The AWI dive team
Interested in the AWIPEV underwater observatory at Ny Alesund work? Please visit the project page here
10.02.2017: Successful dive mission to Antarctic peninsula, King George Island, Potter Cove.
From 27.10.2016 to 7.01.2017, the AWI diveteam conducted the dive mission “Ant Land 16/17” at Potter cove. All planned samplings and underwater measurements could be done succesfully as well as som additional experimehts were possible. In total, 72 dives with 27h dive time were performed. The dive team was leaded by an Argentina dive mission leader and included Elisa Merz (University of Rostock), Christopher Nowak (University Bremen) and Ralf Hoffmann (AWI) as mission divers. Additionally, Dr. Moritz Holtappels was on site for additional scientific experiments.
The aim of the expedition was to adress the question if melting Antarctic glaciers influence benthic matter fluxes. Three dive sites in Potter Cove, were chosen, each influenced by the melting Fourcade Glacier in a different intensity. The main tasks of the diving scientists was to deploy and to recover a profiler frame, benthic chambers and an Eddy correlation frame. The profiler frame enabled the determination of the diffusive oxygen flux. Benthic chambers and the Eddy correlation frame enabled the determination of the total oxygen uptake in different areas. Additionally, sediment cores were sampled from the three different sites. The cores were used in different lab experiments. The first experiment dealt with the question if and over which scale melting glaciers influence benthic nitrogen fluxes. The second experiment dealt with the topic of the potential primary production of the microphytobenthos at the three sites. Additionally sediment samples were used to take subsamples for the measurement of abiotic and biogenic sediment parameters as well as to determine abundances and biomass of the macrofauna, meiofauna and bacteria community.
The success of the expedition was possible due to the very good weather conditions during the stay and a highly motivated dive team and most important, by the selfless and great support of the argentine military divers Malevo, Pupi and Mario.
Ralf Hoffmann, March 2017
07.12.2016: Pressemeldung - Forscher entwickeln Unterwasser-Observatorium
Die Weiten des Meeres und dessen zeitweise harschen Bedingungen stellen Meeresforscher häufig vor schwierige Situationen. In der Nordsee nahe Helgoland haben Wissenschaftler des Thünen-Instituts für Seefischerei, des Alfred-Wegener-Instituts (AWI) und des Helmholtz-Zentrums Geesthacht (HZG) jetzt ein außergewöhnliches Gerät ausgebracht: ein optisch-akustisches Unterwasser-Observatorium....(mehr)
14.11.2016: Successful year 2016 at Svalbard for the AWI dive-group: Three dive-missions completed
The year 2016 comes to an end and the AWI dive-group looks back on three busy and successful dive-missions in Svalbard's Kongsjord on 79°N.
The group opened the diving-season in the middle of winter in February 2016 when three AWI divers together with a team of technicians from 4H Jena and from the French cooperation partners "Laboratoire d'Océanographie Villefranche" travelled to Ny Ålesund. Their mission during this early time of the year was the regular surface- and underwater maintenance of the "Spitsbergen Underwater Observatory" (COSYNA@AWIPEV Underwater Observatory).
This observatory is located at the south shore of the Kongsfjord (West Spitsbergen) and includes various scientific instruments at land and under water. The observatory makes continuous remote controlled measurements of the main oceanographic data such as temperature, salinity, oxygen, turbidity, pCO2 and others. The system also supports a permanent operating ADCP (Acoustic Doppler Current Profiler - fig. 5) for continuous current and wave measurements, a remote-controlled stereo-optical unit to assess species abundance and length-frequency distributions of the macrobiotic community including the fish (fig. 3) and instruments from cooperating institutes (fig. 6).
The system is completed by a land based "ferry-box" system pumping seawater from the observatory's base station in 12 m water depth for further water analysis and sampling. Since this base unit including the seawater pumps and the so called under water node (the underwater supply unit for power and network - fig. 2) is operated year-round, it is heavily exposed to the harsh arctic conditions such as low temperatures, currents, high sedimentation and the omnipresent threat by drifting ice and icebergs. Therefore, together with the regular maintenance, the dive-team had to repair some ice caused damages and exchanged some technical parts and instruments to bring the observatory back to a 100% operating status for the upcoming season.
Even though the permanent darkness of the polar winter (fig. 1) was already replaced by some dawn light at least for a few hours per day, the divers under water had to work in almost complete darkness with underwater lights mounted to their equipment to illuminate the working area. Finally, everything went well during this first mission and even the repositioning of a 400 kg concrete anchor-block which was displaced by an iceberg, worked out quite well in complete darkness.
Unfortunately, only few weeks after the AWI dive team left NyAlesund, another iceberg hit the underwater cable so that the communication to the underwater part of the observatory started to become critical. With the help of the AWIPEV station personal, the REMOS part of the underwater observatory (the camera- and profiling observation unit of the COSYNA@AWIPEV Underwater Observatory) could be "parked" safely on the seafloor. Fortunately, the land based "ferry-box" system could be still operated in an emergency mode so that the measurements of the basic hydrographic variables could be continued. Because of this damage, the AWI dive-group carried out a second mission in April to repair the underwater system and to resolve some further damages.
During this second stay, the daylight was back, the weather conditions were good and the dive locker including the dive boat were prepared within 1½ days, so that the second mission could start. For this stay, a team of three experienced divers were chosen to recover the underwater observatory system, to exchange parts, repair pumps and bring the whole system back into operation mode within a few days.
The third dive-mission in 2016 took place in September/October for eight weeks with the overall goal to collect more scientific data and information on the polar fjord system during autumn and beginning winter. During this stay, the dive team supported a total of eight different scientific projects with seven projects, partly with own diving scientists on site which were integrated in the core dive team. The main task for most of the projects was the collection of samples such as macro algae, benthic animals or sediment cores. Furthermore, several experimental underwater set-ups had to be installed, maintenance of existing set-ups had to be carried out and long-term experiments had to be checked and evaluated. Additionally, the underwater observatory was upgraded by two new concrete fundaments carrying new light-loggers (PAR). In this regard, special thanks goes to the department "AWI technical workshop" (Erich Dunker and Matthias Littmann) which provided us, as always over the last years, with perfect scientific equippement to install and improove the under water installations at the Svalbard observatory.
Unfortunately, unusual strong rainfall and relatively warm temperatures dominated the last time of the year 2016 so that high sedimentation-rates caused a quite bad visibility under water, which sometimes made our efficient work under water quite problematic. Nevertheless, at the end everything worked out, all experiments for the winter season 2016-2017 were installed and all involved parties are looking forward to the winter results in spring 2017. Altogether, during the 2016 Svalbard dive-missions, the AWI dive team did more than 120 dives in the Kongsfjord with a total of eight different divers, supporting nine scientific projects with at least four scientific institutions involved.
29.10.2016: News from the AWIPEV Underwater observatory at 79°N.
A filmteam from the Norwegian broadcast visited the AWIPEV underwater observatory in September 2016 during our maintenance stay at NyAlesund. Please click here to go to the TV-story.
10.01.2016: Course "European Scientific Diver - geprüfter Forschungstaucher 2016" open for application.
The upcoming course "European Scientific Diver - geprüfter Forschungstaucher 2016" is now open for application. Please click here to go to the course site where you can read (and download) all informations how to apply for the course and which requirements you have to fulfill to apply.
20.11.2015: AWI dive expedition to the German Antarctic Station Neumayer III started
See the weekly reports in the Neumayer III Blog AtkaXpress
18.11.2015: Field campaign of the Master student Jonas Löb successfully finished.
Since the beginning of September Jonas Löb from Oldenburg University was part of our scientific diving group to work on his Master thesis. The topic of the thesis is about the effect of feeding pressure by herbivorous animals on the depth zonation of Fucus spp. on Helgoland. Therefore 24 enclosure cages (see photo - 12 fully closed and 12 half closed) and 12 open rings were equipped with the brown algae Fucus serratus and Fucus vesiculosus and were deployed near the MarGate experimental field in a water depth of around 5m. The experiment started on the 24th of September and lasted six weeks. On November the 5th the cages and rings were successfully recovered. The comparative approach shall increase the understanding how herbivorous feeding pressure affects different algal species, if feeding pressure can restrict the lower depth limit of F. vesiculosus compared to F. serratus and additionally, whether the exclusion of herbivorous feeding pressure increases the competitive ability of F. vesiculosus compared to F. serratus.
07.11.2015: Field campaigns of the two Master students Gustavo Gumprich and Kristin Sprenger successfully finished.
After three months of intense field work with a lot of scientific diving in the underwater experimental field MarGate off Helgoland, the two Master students and Certified Research Divers Gustavo Gumprich and Kristin Sprenger from University Rostock have successfully finished their field work. In stratified line-transect counting in 5 m and 10 m water depth, they assessed the fish and crustacean community in the MarGate field in the month August to October. The data are now analyzed and the two theses will be submitted before Christmas. The two studies are done in the framework of the long term project „Impact of coastal defence structures (tetrapods) on demersal fish and decapod crustaceans“ at the AWI Centre for Scientific Diving.
23.03.2015: Antarctic dive mission 2015 at Carlini Base
After some years of abstinence of an AWI dive team at the Dallmann Laboratory/ Carlini Station at Potter Cove (King George Island, Antarctic) we could successfully perform all planned diving tasks during our expedition Ant Land 15/16.
This year’s campaign includes several highlights. First of all it was the first time that an international dive team under the aegis of the AWI dove together, namely Francesca Pasotti (Ghent University, Belgium), Anders Torstensson (University of Gothenburg, Sweden) and Ralf Hoffmann (AWI, Germany), under the supervision of Argentine army divers. This was possible due to a risk assessment including the strictest rules for scientific diving of each country, which is unique until now. A second highlight was the first time performance of in situ incubations and in situ measurements of oxygen profiles in the Potter Cove to detect the oxygen consumption of micro-, meio- and macrofauna benthic sediment communities. These measurements were performed at three different sites, which differ in time of being ice-free from the shrinking Fourcade Glacier. A comparison of the results will give insights in the development of sediment communities and associated benthic biogeochemistry in a changing Antarctic environment.
In total 68 dives were performed with a sum of over 28 h of diving. The main tasks were the deployment and recovery of benthic chambers, power supply and a profiler frame. Besides these tasks water samples from the benthic chambers and different sizes of sediment cores were taken as well as photo surveys and macroalgae collections performed. All dives were supported and guided by the argentine divers Alfredo Torres and Ezequiel Tulian
We like to thank Philipp Fischer, Maria Asplund, Alain Norro and Willy Mercury for creating the scientific diving risk assessment which represented a complex and unique international exercise, Katharina Zacher, Angela Wulff, Ulrike Braeckman and Nadja Küpper for being such great colleagues during our stay and last but not least Oscar Gonzalez, Gabriela Campana, Francisco Ferrer and the whole Carlini-Family for all the support.
Francesca Pasotti, Anders Torstensson & Ralf Hoffmann, March 2015
05.01.2015: Antarktis Tauchexpedition ANTXX-2 / PS89
Im Rahmen der Polarsternfahrt ANTXXX-2 / PS89 wurden im Januar 2015 erstmals Tauchgänge von der deutschen Antarktisstation Neumayer III aus durchgeführt. Im Rahmen der Expedition wurden Verfahren und Techniken zur Lokalisierung und Bergung von wissenschaftlichen Geräten durch eine etwa 3m dicke Meereisschicht erprobt. Die Neumayer-Station des Alfred-Wegener-Institutes erwies sich dabei als sehr gute logistische Plattform für Untereis-Tauchgänge in der Atka-Bucht. Im Rahmen der Mission wurden auch Prospektionstauchgänge bis zu einer Wassertiefe von 10 m und bis zu 60m unter das Meereis durchgeführt. Dabei konnte auch die Situation des Tauchens unter der 2-3 m starken sog. „Plättcheneis"-Schicht erprobt werden.
Neben der reinen Methodenerprobung wurde zusätzlich ein kurzer biologischer Survey der Untereisfauna der Atkabucht durchgeführt. Es zeigte sich eine erstaunlich diverse Gemeinschaft mit Krill, Amphipoden, Fischen, Schwämmen und verschiedenen Anthozoenarten die sich in der Nähe, auf oder in der Plättcheneisschicht aufhielten.
Zusammenfassend lässt sich feststellen, dass sich die vom AWI Tauchzentrum teilweise erstmals eingesetzten Geräte und Methoden zum wissenschaftlichen Tauchen in der Antarktis als belastbar und sicher gezeigt haben um Untersuchungen am oder unter mehrjährigem Eis durchzuführen.
Das AWI Tauchzentrum bedankt sich ganz herzlich bei der Besatzung der Neumayer III Station für die großartige Unterstützung während unseres Aufenthaltes und wünscht insbesondere den Überwinterern alles Gute für das kommende Jahr.
Christoph Walcher, Marco Warmuth & Philipp Fischer
The 2014 AWI dive mission on Svalbard successfully finished end of September.
On September 29th the AWI dive group closed the 2014 Arctic dive season at the joined German / French AWIPEV-Station in Ny Ålesund on Svalbard.
Due to the fact that West-Spitsbergen was under the influence of the upcoming winter already since early September the last dives in the Kongsfjord area were conducted under real Arctic conditions such as low temperature, snowfall, strong wind and icy crusts on boat and equipment.
The 2014 diving campaign started in early June with a small group of divers arriving in Ny Ålesund to prepare the dive-locker, the dive-boat and the rescue chain as well as to check and test the decompression chamber and the diving equipment. Until the end of September a dive group of minimum 3 scientific divers was permanent on site to support a wide variety of scientific projects in the Kongsfjord area. During the campaign a total of 10 AWI related long- and short-term projects were supported by the divers mainly by taking biological samples, installing and maintaining underwater experimental set-ups and carrying out measurements or taking pictures and videos.
Beside this, a new challenge for the scientific divers was the support of an archaeological project dealing with anthropogenic traces underwater carried out by the Netherlands Arctic Institute in cooperation with AWIPEV. During these dives a specified area around the former marble mining site “Ny London” (Bloomstrandhalvoya) was investigated and archaeologically relevant findings had to be named, described, photographed and surveyed. A bulk of technic-related remainings were found and documented which gave some hints on the comprehensive activities during the mining period about 100 years ago.
Furthermore the divers conducted additional dives for other scientific institutes located in Ny Ålesund such as the Norwegian North Polar Institute (biological samples) and the Italian station, KingsBay and the Korean Polar Institute (all technical support dives).
The last days of the season were dedicated to the necessary maintenance and repair work at the AWIPEV Underwater Fjord Observatory. Some repairs had to be carried out at the installation and two new additional scientific instruments from the MPI Bremen and the AWI Helgoland were installed and connected to the underwater node.
All in all, a total of 11 AWI divers and two dive mission leaders (Max Schwanitz and Christoph Walcher) were alternating on site during the entire season. By conducting 259 dives they were able to fulfill all scientific requests and demands.
Max Schwanitz, October 2014
09.07.2014: Report of two Bachelor students of the University of Oldenburg at AWI-CSD.
Between 22th of April and 30th of June Dina Biehn and Miriam Lienkämper stayed at the centre for scientific diving of the Alfred-Wegener-Institute at Helgoland. We are two Bachelor students from the University of Oldenburg and also scientific divers. At Helgoland we were collecting data for our Bachelor Theses about the competition between native and the invasive alga Sargassum muticum. Therefore we had an in situexperiment at the “MarGate” experimental field 400m northeast of Helgoland and an aquarium experiment at “Haus A”. To evaluate the competition of the algae we measured the weight, the length and the efficiency of photosynthesis with our Diving-PAM.
For our measurements, dives, preparation and everything else we had always support from the colleagues of the dive center. Therefore we are very thankful.