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Total sediment thickness of the world's oceans and marginal seas, version 3 (GlobSed)

NCEI's global ocean sediment thickness grid of Divins (2003) updated by Whittaker et al. (2013) has been updated again for the NE Atlantic, Arctic, Southern Ocean, and Mediterranean regions. The new global 5‐arc‐minute total sediment thickness grid, GlobSed, incorporates new data and several regional oceanic sediment thickness maps, which have been compiled and published for the, (1) NE Atlantic (Funck et al., 2017; Hopper et al., 2014), (2) Mediterranean (Molinari & Morelli, 2011), (3) Arctic (Petrov et al., 2016), (4) Weddell Sea (Huang et al., 2014), and (5) the Ross Sea, Amundsen Sea, and Bellingshausen Sea sectors off West Antarctica (Lindeque et al., 2016; Wobbe et al., 2014). This version also includes updates in the White Sea region based on the VSEGEI map of Orlov and Fedorov (2001). GlobSed covers a larger area than NCEI's previous global grids (Divins, 2003; Whittaker et al. 2013), and the new updates results in a 29.7% increase in estimated total oceanic sediment volume. This dataset has been archived in the framework of the PANGAEA US data rescue initiative 2025.

Dissolved major element (Ca, Sr, Mg, K, Li) concentration data of the western Atlantic Ocean meridional section GA02 (GEOTRACES) and Arctic Ocean cruise JR271 (BODC)

This dataset presents salinity-normalized dissolved major element (Ca, Mg, K, Sr, Li) concentrations in the western Atlantic Ocean and the Arctic Ocean. Atlantic samples were collected along the western meridional GEOTRACES section GA02 comprised of cruises JR057 (Punta Arenas (Chile) 02-03-2011 to Las Palmas (Spain) 06-04-2011 ), PE321 (Bermuda 11-06-2010 to Fortaleza (Brazil) 08-07-2010), PE319 (Scrabster 28-04-2010 to Bermuda 25-05-2010), and PE358 (Reykjavik (Iceland) 29-07-2012 to Texel (Netherlands) 19-08-2012). Samples for dissolved major ions were sub-sampled from trace metal sample collection stored at the Royal Netherlands Institute for Sea Research (NIOZ). Samples for the Arctic Ocean were collected on BODC cruise JR271 (Immingham 01-06-2012 to Reykjavik 02-07-2012). Samples were analysed for Na, Ca, Mg, K, Li and Sr using a Varian-720 ES ICP-OES. Samples were diluted by a factor of 78-82 in 0.12 M HCl to the same final salinity. Multiple spectral lines were selected for each element, and samples were corrected for instrumental drift by sample-standard bracketing with IAPSO P157 diluted to the same final salinity. Calibration was performed on 7 dilutions of IAPSO P157. Element-to-sodium ratios were calculated for all combinations of spectral lines. Assuming a constant Na-to-salinity (PSU)=35 ratio, the element/Na ratios were multiplied by 0.46847 µmol kg-1 to obtain the salinity (PSU)-normalized element concentration, and by the ratio of practical to absolute salinity (TEOS-10). The TEOS-10 absolute salinities were calculated from EOS-80 values using the Gibb's Oceanographic Toolbox using the R package 'gsw' (v 1.1-1).

(Table A1) Raw data for both AMT20 Atlantic Ocean transect samples and western Pacific Ocean transect (SO228 and SO256) samples

Sea surface salinity (SSS) is the least constrained major variable of the past (paleo) ocean but is fundamental in controlling the density of seawater and thus large-scale ocean circulation. The hydrogen isotopic composition (δD) of non-exchangeable hydrogen of algal lipids, specifically alkenones, has been proposed as a promising new proxy for paleo SSS. The δD of surface seawater is correlated with SSS, and laboratory culture studies have shown the δD of algal growth water to be reflected in the δD of alkenones. However, a large-scale field study testing the validity of this proxy is still lacking. Here we present the δD of open-ocean Atlantic and Pacific surface waters and coincident δD of alkenones sampled by underway filtration. Two transects of approximately 100° latitude in the Atlantic Ocean and more than 50° latitude in the Western Pacific sample much of the range of open ocean salinities and seawater δD, and thus allow probing the relationship between δD of seawater and alkenones. Overall, the open ocean δD alkenone data correlate significantly with SSS, and also agree remarkably well with δD water vs δD alkenone regressions developed from culture studies. Subtle deviations from these regressions are discussed in the context of physiological factors as recorded in the carbon isotopic composition of alkenones. In a best-case scenario, the data presented here suggest that SSS variations as low as 1.2 can be reconstructed from alkenone δD.

Pliocene-Pleistocene distribution of benthic foraminifers from ODP Hole 110-672A (Table 2)

Site 672 is located on the Atlantic abyssal plain to the east of the Lesser Antilles forearc region. It serves as a stratigraphic reference section for sediments entering the Barbados accretionary prism. A relatively complete Pliocene through lower Pleistocene section was recovered from Site 672 that contains a moderately well-preserved population of benthic foraminifers. Q-mode factor analysis of the benthic population data identified three Pliocene-Pleistocene assemblages that inhabited this site. The Factor 1 fauna, characterized by Nuttallides umboniferus, is commonly associated with the presence of Antarctic Bottom Water (AABW). The Factor 2 assemblage is characterized by Globocassidulina subglobosa, Epistominella exigua, and a combined category of unilocular species. The Factor 3 assemblage is characterized by Epistominella exigua, and Planulina wuellerstorfi. The Factor 2 and 3 faunas are associated with bottom water significantly warmer than that preferred by the Factor 1 assemblage. The distribution of these assemblages has been used to distinguish three climatic intervals in the abyssal environment during the Pliocene-Pleistocene. An early Pliocene warm interval occurred from the Ceratolithus rugosus Subzone to the middle of the Discoaster tamalis Subzone. The upper Pliocene is characterized by oscillations between the Factor 1 and Factor 2 assemblages, which suggests climatic deterioration and increased pulses of AABW flow. The persistence of an essentially modern (Factor 1) fauna throughout the early Pleistocene suggests full glacial development at both poles and a substantial volume of AABW production.

Schwerpunktprogramm (SPP) 1294: Bereich Infrastruktur - Atmospheric and Earth system research with the 'High Altitude and Long Range Research Aircraft' (HALO), NAWDEX - North Atlantic Waveguide and Downstream Impact Experiment

The North Atlantic Waveguide and Downstream Impact Experiment (NAWDEX) aims to provide the foundation for future improvements in the prediction of high impact weather events over Europe. The concept for the field experiment emerged from the WMO THORPEX program and contributes to the World Weather Research Program WWRP in general and to the High Impact Weather (HIWeather) project in particular. An international consortium from the US, UK, France, Switzerland and Germany has applied for funding of a multi-aircraft campaign supported by enhanced surface observations, over the North Atlantic and European region. The importance of accurate weather predictions to society is increasing due to increasing vulnerability to high impact weather events, and increasing economic impacts of weather, for example in renewable energy. At the same time numerical weather prediction has undergone a revolution in recent years, with the widespread use of ensemble predictions that attempt to represent forecast uncertainty. This represents a new scientific challenge because error growth and uncertainty are largest in regions influenced by latent heat release or other diabatic processes. These regions are characterized by small-scale structures that are poorly represented by the operational observing system, but are accessible to modern airborne remote-sensing instruments. HALO will play a central role in NAWDEX due to the unique capabilities provided by its long range and advanced instrumentation. With coordinated flights over a period of days, it will be possible to sample the moist inflow of subtropical air into a cyclone, the ascent and outflow of the warm conveyor belt, and the dynamic and thermodynamic properties of the downstream ridge. NAWDEX will use the proven instrument payload from the NARVAL campaign which combines water vapor lidar and cloud radar, supplemented by dropsondes, to allow these regions to be measured with unprecedented detail and precision. HALO operations will be supported by the DLR Falcon aircraft that will be instrumented with wind lidar systems, providing synergetic measurements of dynamical structures. These measurements will allow the first closely targeted evaluation of the quality of the operational observing and analysis systems in these crucial regions for forecast error growth. They will provide detailed knowledge of the physical processes acting in these regions and especially of the mechanisms responsible for rapid error growth in mid-latitude weather systems. This will provide the foundation for a better representation of uncertainty in numerical weather predictions systems, and better (probabilistic) forecasts.

GTS Bulletin: FEAE75 EDZW - Forecast (details are described in the abstract)

The FEAE75 TTAAii Data Designators decode as: T1 (F): Forecast T1T2 (FE): Extended A1A2 (AE): South-East Asia (Remarks from Volume-C: FORECAST (5 DAYS) FOR THE EASTERN ATLANTIC (IN ENGLISH))

Meeresmilben (Acari, Halacaridae) im tropischen Westaustralien - Vergleich mit der Fauna anderer Regionen Australiens

Die Halacaridae (Meeresmilben) gehören, mit ihrer Körpergröße von 200-500 mym, zum Meiobenthos. Unter den Milben sind sie die einzigen, die vollständig an ein Leben im Meer angepasst sind; sie besiedeln den Bereich von der oberen Gezeitenlinie bis in die Tiefseegräben. Zur Zeit sind etwa 900 Arten bekannt. Im Vergleich zu den Küsten im Osten und Westen des Nordatlantiks zeichnen sich die Australiens durch eine äußerst artenreiche Halacaridenfauna aus: jede geographische Region entlang der Küste scheint in erster Linie eigene Arten zu beherbergen. Die geplanten Probennahmen bei Dampier an der tropischen Nordwestküste Australiens sollen Daten liefern für einen Vergleich mit den bereits bearbeiteten Faunen von Rottnest Island (Südwestaustralien) und dem Great Barrier Reef (Ostaustralien).

Das CO2-System im Ozean: CO2-Verteilung und Analysenvergleich bei der Messung der Alkalinitaet, des gesamten geloesten anorganischen Kohlenstoffs und des pH im Nordatlantik auf der RSS DISCOVERY vom 10.-27. Juni 1990

GTS Bulletin: FEAE55 EDZW - Forecast (details are described in the abstract)

The FEAE55 TTAAii Data Designators decode as: T1 (F): Forecast T1T2 (FE): Extended A1A2 (AE): South-East Asia (Remarks from Volume-C: FORECAST (5 DAYS) FOR THE EASTERN ATLANTIC (IN GERMAN))

Schwerpunktprogramm (SPP) 1294: Bereich Infrastruktur - Atmospheric and Earth system research with the 'High Altitude and Long Range Research Aircraft' (HALO), Einfluss von Jet-Front Systemen in der oberen Troposphäre auf die mesoskalige Struktur der Tropopauseninversionsschicht und Stratosphären-Troposphären Austausch (MESO-TIL)

Der vorliegende Antrag ist der HALO Mission WISE zuzuordnen. Ein besonderes Augenmerk liegt dabei auf der Bildung der Tropopauseninversionsschicht (TIL) und deren Einfluss auf Stratosphären-Troposphären Austausch (STE) auf der Mesoskala. Diesem Projekt dienen idealisierte Studien der TIL in baroklinen Lebenszyklen als Grundlage. Die Hauptziele sind dabei die Überprüfung der Ergebnisse der idealisierten Studien zur TIL Bildung genauso wie ein erweitertes Verständnis der Prozesse, die zum STE auf der Mesoskala beitragen. Dabei soll auf drei wissenschaftliche Fragestellungen genauer eingegangen werden: (1) Wie stark schwankt die TIL in ihrem Auftreten über dem Nordatlantik, vor allem im Bereich barokliner Lebenszyklen und im Bereich von STE? (2) Welche Prozesse liefern den größten Beitrag zur TIL auf der Mesoskala und welchen Einfluss hat dies auf STE? (3) Wie groß ist der Beitrag von klein-skaligen Wellen in der unteren Stratosphäre auf die TIL Bildung und die Ausdehnung der extratropischen Mischungsschicht? Eine Kombination von Methoden wird verwendet werden um diese Fragen zu beantworten. Analysedaten des EZMW werden zusammen mit Lagrangeschen Methoden benutzt, um die TIL und STE über dem Nordatlantik zu untersuchen. Der Nordatlantik ist das Gebiet, das auch während WISE untersucht werden soll. Darüber hinaus sollen für WISE hoch aufgelöste Modellsimulationen mit dem neuen numerischen Wettervorhersagemodell ICON durchgeführt werden. Dabei sollen zum einen die Beiträge diverser Prozesse auf die Bildung der TIL am Beispiel von realen Zyklonen und Antizyklonen untersucht werden. Des Weiteren sollen die Modelldaten zusammen mit Beobachtungsdaten verwendet werden um den Einfluss der TIL und von klein-skaligen Wellen auf die vertikale Ausdehnung der extratropischen Mischungsschicht zu bestimmen.

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