PS121 - Weekly Report No. 2 | 18.08. – 25.08.2019
Working in Hausgarten
A large part of the work and projects that we scientists planned for this expedition are closely related to furthering the long-term observatory HAUSGARTEN, established by the AWI’s Deep-Sea Group 20 years ago, and to supporting the Helmholtz Infrastructure Initiative FRAM (Frontiers in Arctic Marine Monitoring). The long-term observatory Hausgarten is a network of twenty stations in the Fram Strait, whose coordinates are re-visited by us every year in the summer months.
We are a multidisciplinary team of biologists, physicists, chemists, engineers, and technicians, who have the common goal of better understanding the marine biodiversity and climate-related processes in the Arctic Ocean. Our research in the long-term observatory HAUSGARTEN covers almost all parts of the marine ecosystem. It reaches from the water column to the seafloor, from the relatively shallow area of the Spitzbergen shelf to the deepest point in the Arctic, the Molloy Deep, as well as from the smallest bacteria to microalgae through to larger planktonic and benthic organisms. The results of our research should contribute to better identifying and quantifying the effects of sea ice and climate change for marine ecosystems in the Arctic. The Fram Strait is a very good region for this research, because here relatively warm ice-free areas with water masses of Atlantic origin, as well as cold, ice-covered areas with water masses of polar origin are relatively close to one another and can be comparably investigated.
At the stations of the long-term observatory, a whole array of complementary standardized investigations is conducted, that together should give as complete a picture as possible of the present state of the marine ecosystem and its functioning in the Fram Strait. This requires annual deployment of samplers and optic observation systems for studies in the water column and on the seafloor, as well as deployment of an AUV (autonomous underwater vehicle) and an ROV (remotely operated vehicle). The annually repeated investigations in summer became part of the Helmholtz Infrastructure Initiative FRAM some years ago, through the installation of anchored sensors, samplers, and automatic measurement systems, that collect and deliver information on the most important ecological parameters throughout the year. The whole-year measurements are essential for assessing the state of the Arctic ecosystem as completely as possible, because ecosystem functions have strong underlying seasonal patterns.
The work in the past week has included furthering the long-term observatory HAUSGARTEN and conducting ancillary projects IMMIPLANS (University of Bremen) and CarCASS (GEOMAR), whose research goals are complementary to the questions asked by the Hausgarten team. The weather conditions were perfect over the past week, and so the varied instruments could be deployed and exchanged as planned. In mostly calm seas, the moorings were exchanged, various lander systems were deployed and recovered, and the water column and the seafloor were sampled. The highlights of the week were certainly the two ROV deployments. With this vehicle, the actions of an autonomous benthic crawler outfitted with cameras and sensors could be filmed on the seafloor, and experiments about the effects of ocean acidification on organisms on the seafloor could be completed. The ROV delivered very impressive live footage of brittle stars and amphipods reacting to bait in the form of squid, which was deployed by the ROV.
The mood on board is good. We will report on our work in the western Fram Strait next week.
With best wishes from all expedition participants,
(Translation: Kirstin Meyer-Kaiser)