Beschreibung: Highlights: • A first standardized and publicly available Holocene relative sea-level database for the Baltic Sea is presented. • The database holds 1099 revised data points with an estimation of vertical and chronological uncertainties. • Negative RSL tendencies prevail over the positive and complex tendencies in the Baltic Sea Basin. • Mid-Holocene RSL highstand occurred around 7.5–6.5 ka BP being consistent with the end of the final melting of the LIS. • The contribution of ice loading in the eastern Baltic Sea Basin is likely overestimated in the ICE-5G and ICE-6G_C models. Abstract: We present a compilation and analysis of 1099 Holocene relative shore-level (RSL) indicators located around the Baltic Sea including 867 relative sea-level data points and 232 data points from the Ancylus Lake and the following transitional phase. The spatial distribution covers the Baltic Sea and near-coastal areas fairly well, but some gaps remain mainly in Sweden. RSL data follow the standardized HOLSEA format and, thus, are ready for spatially comprehensive applications in, e.g., glacial isostatic adjustment (GIA) modelling. We apply a SQL database system to store the nationally provided data sets in their individual form and to map the different input into the HOLSEA format as the information content of the individual data sets from the Baltic Sea area differs. About 80% of the RSL data is related to the last marine stage in Baltic Sea history after 8.5 ka BP (thousand years before present). These samples are grouped according to their dominant RSL tendencies into three clusters: regions with negative, positive and complex (transitional) RSL tendencies. Overall, regions with isostatic uplift driven negative tendencies dominate and show regression in the Baltic Sea basin during the last marine stage. Shifts from positive to negative tendencies in RSL data from transitional regions show a mid-Holocene highstand around 7.5–6.5 ka BP which is consistent with the end of the final melting of the Laurentide Ice Sheet. Comparisons of RSL data with GIA predictions including global ICE-5G and ICE-6G_C ice histories show good fit with RSL data from the regions with negative tendencies, whereas in the transitional areas in the eastern Baltic, predictions for the mid-Holocene clearly overestimate the RSL and fail to recover the mid-Holocene RSL highstand derived from the proxy reconstructions. These results motivate improvements of ice-sheet and Earth-structure models and show the potential and benefits of the new compilation for future studies.

Beschreibung: Raw data acquired by a thermosalinograph (SBE21, SeaBird GmbH) on board RV HEINCKE were processed to receive a calibrated and validated data set of seawater temperature and salinity. Data were downloaded from DAVIS SHIP data base (https://dship.awi.de) with a resolution of 1 sec. The SBE21 was equipped with an additional external temperature sensor (SBE38, Sea-Bird GmbH). Raw data are converted to temperature and conductivity values using the calibration coefficients from the calibration before deployment. However, data can only be finally processed after replacement and renewed calibration because correction values for the sensor drift can only be obtained by the post cruise calibration. The thermosalinograph on board RV HEINCKE is exchanged about once a year and calibration procedures are conducted after every exchange. Salinity was calculated according to the instructions from the Practical Salinity Scale PSS-78 using the obtained internal temperature and conductivity data. Processed data are provided as 1min means of salinity and seawater temperature aligned with position data taken from master track of the respective cruise. Quality flags are appended according to the SeaDataNet Data Quality Control Procedures (version from May 2010).

Beschreibung: Raw data acquired by an SBE21 thermosalinograph and an auxiliary SBE38 temperature sensor (Sea-Bird Scientific, USA) installed in an underway seawater flow-through system on board RV Heincke were processed to yield a calibrated and validated data set of seawater temperature and salinity along the cruise track. The seawater inlet is located at a depth of 2 m. The raw hexadecimal data were downloaded from the DAVIS SHIP data base (https://dship.awi.de) at a resolution of 1 s, and converted to temperature and conductivity using the pre-deployment factory calibration coefficients. The converted data were averaged to 1 min values, outliers were removed, and sensor drift was corrected using coefficients obtained from a post-season calibration performed at Sea-Bird at the end of the measurement season. Salinity was calculated from internal temperature, conductivity and pressure according to the PSS-78 Practical Salinity Scale. Processed data are provided as 1 min means of seawater temperature, conductivity and salinity, aligned with position data taken from the master track. Quality flags are appended according to the SeaDataNet Data Quality Control Procedures (version from May 2010). More details are described in the attached processing report.

Beschreibung: A recently encountered fossil oyster bed (Ostrea edulis) located in the sublittoral zone offshore the island of Helgoland (German Bight, Europe) was investigated. During a ship campaign in June 2019 onboard RV „Mya II“, the local extent and surface properties of the oyster bed were determined by submersible underwater drift video and grab sampling. The aim of this study was to facilitate the first description of a sublittoral oyster bed in the area and to understand its past ecological state and the reasons of its demise. Ostera edulis and associated habitats disappeared from the North Sea at the beginning of the last century and are a current focal point of restoration initiatives across Europe. Oyster shells were collected from the grab samples, cataloged and systematically analyzed. The weight of the valves was determined on a laboratory scale in grams with a precision of two decimals. The length (mm), width (mm), and degree of infestation (%) by the boring sponge Cliona sp. were digitally determined for each valve on the base of photographic images in the open-source software ImageJ (https://imagej.nih.gov/ij/).

Beschreibung: Raw data acquired by position sensors on board RV Heincke during expedition HE592 were processed to receive a validated master track which can be used as reference of further expedition data. During HE592 the inertial navigation system IXSEA PHINS III and the GPS receivers Trimble Marine SPS461 and SAAB R5 SUPREME NAV were used as navigation sensors. Data were downloaded from DAVIS SHIP data base (https://dship.awi.de) with a resolution of 1 sec. Processing and evaluation of the data is outlined in the data processing report found at EPIC repository https://hdl.handle.net/10013/epic.03d07851-ca02-43dc-86d0-739d93d017b6. Processed data are provided as a master track with 1 sec resolution derived from the position sensors' data selected by priority and a generalized track with a reduced set of the most significant positions of the master track.