No abstract

No abstract

No abstract

Marine data are needed for many purposes: for acquiring a better scientific understanding of the marine environment, but also, increasingly, as marine knowledge for decision making as well as developing products and services supporting economic growth. Data must be of sufficient quality to meet the specific users' needs. It must also be accessible in a timely manner. And yet, despite being critical, this timely access to known-quality data proves challenging. Europe's marine data have traditionally been collected by a myriad of entities with the result that much of our data are scattered throughout unconnected databases and repositories. Even when data are available, they are often not compatible, making the sharing of the information and data aggregation particularly challenging. In this paper, we present how the European Marine Observation and Data network (EMODnet) has developed over the last decade to tackle these issues. Today, EMODnet is comprised of more than 150 organizations which gather marine data, metadata, and data products and make them more easily accessible for a wider range of users. EMODnet currently consists of seven sub-portals: bathymetry, geology, physics, chemistry, biology, seabed habitats, and human activities. In addition, Sea-basin Checkpoints have been established to assess the observation capacity in the North Sea, Mediterranean, Atlantic, Baltic, Artic, and Black Sea. The Checkpoints identify whether the observation infrastructure in Europe Martín Míguez et al. EMODnet: Visions and Roles meets the needs of users by undertaking a number of challenges. To complement this, a Data Ingestion Service has been set up to tackle the problem of the wealth of marine data that remain unavailable, by reaching out to data holders, explaining the benefits of sharing their data and offering a support service to assist them in releasing their data and making them available through EMODnet. The EMODnet Central Portal (www.emodnet. eu) provides a single point of access to these services, which are free to access and use. The strategic vision of EMODnet in the next decade is also presented, together with key focal areas toward a more user-oriented service, including EMODnet for business, internationalization for global users, and stakeholder engagement to connect the diverse communities across the marine knowledge value chain.

The chemical composition and vertical distribution of sediment phosphorus (P) in shallow coastal sediments of the northeastern Baltic Sea (BS) were characterized by sequential extraction. Different P forms were related to chemical and physical properties of the sediments and the chemistry of pore water and near-bottom water. Sediment P composition varied among the sampling sites located in the Archipelago Sea (AS) and along the northern coast of the Gulf of Finland (GoF): the organic rich sites were high in organic P (OP), while apatite-P dominated in the area affected by sediment transportation. Although the near-bottom water was oxic, the sediments released P. Release of P was most pronounced at the site with high sediment OP and reduced conditions in the sediment-water interface, indicating that P had its origins in organic sources as well as in reducible iron (Fe) oxyhydroxides. The results suggest that even though these coastal areas are shallow enough to lack salinity stratification typical for the brackish BS, they are vulnerable to seasonal oxygen (O 2 ) depletion and P release because of their patchy bottom topography, which restricts mixing of water. Furthermore, coastal basins accumulate organic matter (OM) and OP, degradation of which further diminishes O 2 and creates the potential for P release from the sediment. In these conditions, an abundance of labile OP may cause marked efflux of P from sediment reserves in the long-term.

No abstract

During Ocean Drilling Program Leg 208, six sites were drilled at water depths between 2500 and 4770 m to recover Cenozoic sediments on the northeastern flank of Walvis Ridge. Previous drilling in this region (Deep Sea Drilling Project [DSDP] Leg 74) recovered pelagic oozes and chalk spanning the Cretaceous/Paleogene (K/Pg), Paleocene/Eocene, and Eocene/Oligocene boundaries. The composite sections, recovered via double and triple coring, provide a detailed history of paleoceanographic variation associated with several prominent episodes of early Cenozoic climate change, including the K/Pg boundary, Paleocene/ Eocene Thermal Maximum (PETM), early Eocene Climatic Optimum, and early Oligocene Glacial Maximum. The PETM interval, the main target of Leg 208, was recovered at five sites along a depth transect of 2.2 km. A prominent red clay layer marks the boundary sequence at all sites. Additionally, two as-yet undocumented early Eocene hyperthermal events were recovered: Elmo and X, dated at ~53.5 and ~52 Ma, respectively. A number of postcruise investigations were undertaken on these critical intervals, principally to improve stratigraphic control and the resolution of proxy records of climate and ocean chemistry, and to better understand the regional impacts of these events on biota. The major contributions of Leg 208 include (1) development of new orbitally tuned chronologies for the Paleocene and lower Eocene, (2) high-resolution characterization of Paleocene/Eocene boundary carbonate dissolution horizons and correlation to the carbon isotope excursion and PETM, (3) development of the first marine-based carbon isotope record of terrestrial n-alkanes for the PETM, (4) documentation of the ecological impacts of the PETM on calcareous algae, (5) resolving the full magnitude of the

No abstract