Baffin Bay Ice-Ocean-Sediment Interactions Cruise Report
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BIOS 2019 Baffin Bay Ice-Ocean-Sediment Interactions Research Cruise on HDMS Lauge Koch Aasiaat – Qaanaaq – Carey Islands – Aasiaat 19 Aug – 8 Sep 2019 Cruise report Foreword In August - September 2019, a team of marine researchers of GEUS and Aarhus University sailed on HDMS Lauge Koch to study the sea floor and its underlying sediments in the northern Baffin Bay. This report is a detailed account of all samples and data collected during the 3- week research cruise. It is intended to serve as a reference for anyone working on the data or samples and as a guide for future users of LAKO as a platform for marine research. This report is written by co-chief scientists Christof Pearce and Paul Knutz, with contributions from everyone on the science team. Acknowledgements First and foremost, we thank the Captain and crew of HDMS Lauge Koch for their hospitality, good company and all the help we received to complete our science plan and make this a successful cruise. No matter what time of day or night, we received all the assistance we needed on deck for heavy lifting, on the bridge for navigation and planning, or in the office (flex room) when we had technical difficulties with the network or with one of our instruments. Thank you to Bettina Ovgaard of Arctic Command for facilitating all cruise planning meetings and acting as our communication channel with LAKO. Thanks to Marianne Vestergaard of GEUS for providing logistical assistance related to our travel arrangements and export permits. The crew of hydrographers (Søopmåling) provided us with instructions for collecting and storing seafloor and water column data. This research cruise is made possible by funding from the Dansk Center for Havforskning, the Carlsberg Foundation, Geocenter Danmark, and the Aarhus University Research Foundation. Contents Foreword ................................................................................................................................... 3 Acknowledgements ................................................................................................................... 3 Participants................................................................................................................................ 6 Objectives .................................................................................................................................. 8 Geographical region and cruise track ....................................................................................... 8 HDMS Lauge Koch (LAKO) as research platform ....................................................................... 9 Mobilization .............................................................................................................................. 10 Deck configuration ................................................................................................................... 10 Performance of DCH deck-machinery ...................................................................................... 11 Stowing after end of operations............................................................................................... 13 Scientific equipment ............................................................................................................... 13 Multichannel seismic acquisition ............................................................................................. 13 Sediment corers ........................................................................................................................ 19 Multibeam echosounder for backscatter, water column and bathymetry ............................. 22 Innomar sub-bottom profiler investigations ............................................................................ 24 Temperature and velocity profiling of water column .............................................................. 29 Surface water filtration ............................................................................................................ 29 Data & preliminary results ...................................................................................................... 31 Biogeochemistry ....................................................................................................................... 31 Surface water filtration and measurements ............................................................................ 32 Seismic data .............................................................................................................................. 33 Multibeam bathymetry data .................................................................................................... 37 Sub-bottom profiler investigations .......................................................................................... 37 Water column data ................................................................................................................. 38 Fieldwork on Carey Islands ..................................................................................................... 40 References ............................................................................................................................... 43 Appendix 1: Daily Summary Reports ....................................................................................... 44 Appendix 2: Seismic log table ................................................................................................. 49 Appendix 3: Sediment cores overview map............................................................................ 51 Appendix 4: Sediment coring summary .................................................................................. 52 Appendix 5: Sediment core photographs/descriptions .......................................................... 53 LK19-ST4-4G ............................................................................................................................. 53 LK19-ST8-14G ........................................................................................................................... 54 LK19-ST13-17G ......................................................................................................................... 55 Appendix 6: Innomar sub-bottom transects across the coring stations ................................. 56 Appendix 7: Ferrybox data and water filter stations .............................................................. 59 5 Participants Science Party Name Affiliation Role on board, expertise Christof Pearce (CP) Aarhus University Co-chief scientist, sediment coring, paleoceanography Paul Knutz (PKN) GEUS Co-chief scientist, seismic acquisition, marine geophysics Katrine Juul Andresen Aarhus University Seismic acquisition and processing, sub- (KJA) bottom profiling and swath bathymetry, marine geophysics Henrieka Detlef (HD) Aarhus University Sediment coring, Water filtration, Paleoceanography and geochemistry Katrine Elnegaard Hansen Aarhus University Sediment coring, paleoceanography and (KEH) micropaleontology John R Hopper (JRH) GEUS Seismic acquisition and processing, marine geophysics Nicolaj Krog Larsen (NKL) Aarhus University Sediment coring, terrestrial fieldwork, Quaternary Geology Niels Nørgaard-Pedersen GEUS Sub-bottom profiling, swath bathymetry, (NNP) sediment coring, marinegeophysics and paleoceanography Lars-Georg Rödel (LGR) GEUS Swath bathymetry, sub-bottom profiling, water column profiling, technician Hans Røy (HR) Aarhus University Sediment coring, winch operations, geomicrobiology Per Trinhammer (PT) Aarhus University Onshore technician, (de-)mobilizing seismic equipment and DCH infrastructure (winch and A-frame) 6 Crew (Royal Danish Navy) Name Position NATO Rank Morten H. Brandt Commanding Officer (CHEF) OF-2 Lieutenant Commander Camilla Boye Executive Officer (NK) OF-2 Lieutenant Commander Ditte R. Olesen Navigational Officer (NAO) OF-1 Lieutenant René Olsson Chief Engineer (TKO) OF-3 Commander Erik J.K. Schmidt Quartermaster (BM) OR-8 Senior Chief Petty Officer Lars Søltoft-Cederstrøm Supply (FSB) OR-5 Petty Officer Tommy S. Sørensen Radio OR-3 Able Rating Specialist Tommy T. Jacobsen Cook OR-3 Able Rating Specialist Daniel R. Sidor Food & Bakery OR-3 Able Rating Specialist Peter J. Anderson Deckhand OR-3 Able Rating Specialist Simon Wildt Settgast Deckhand OR-1 Able Rating Mikkel Diederichsen Deckhand OR-3 Able Rating Specialist Daniel Jensen Deckhand OR-2 Able Rating Emil Nordvig Sørensen Deckhand OR-1 Able Rating Rasmus Z. Røge Deckhand OR-2 Able Rating Allan Berg Electrician OR-3 Able Rating Specialist Glen M.T. Bæk Engine OR-3 Able Rating Specialist Jan Hoegh Engine OR-3 Able Rating Specialist Lars Kragh Data OR-3 Able Rating Specialist Simon Kristensen Weapon OR-2 Able Rating 7 Objectives The overall aim of the BIOS-LAKO cruise was to gain new data and information on (1) seismic- stratigraphy in northern Baffin Bay, (2) collect seabed sediment cores with the intent of understanding ice-ocean interactions, primarily through the Holocene, and (3) obtain geological samples in the form of bedrock and raised marine sediments on Carey Islands. The Greenland ice sheet (GrIS) is the largest freshwater reservoir of the northern hemisphere. Recent studies have highlighted the sensitivity of the GrIS to ongoing climate warming and its potential impact on sea-level rise and the Atlantic meridional overturning circulation (AMOC) (Khan et al., 2010; Hansen et al., 2016). The full range of forcing and feedbacks – oceanic, atmospheric,