GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
  • 1
    facet.materialart.
    Unbekannt
    AGU (American Geophysical Union)
    In:  Journal of Geophysical Research: Oceans, 94 (C3). pp. 3201-3210.
    Publikationsdatum: 2020-10-20
    Beschreibung: Two buoy types have been tested with respect to their drift performance under drogued and undrogued conditions. Additionally, forces acting on the buoys were measured directly. Quadratic drag laws have been confirmed for the drag in water and the combined drag of wind and waves. Stokes drift contributes about one half to the wind factor of 0.023, which is obtained for undrogued buoys in the Atlantic. The forces on a windowshade drogue are given by a linear relation between force and water velocity for speeds exceeding 10 cm/s. They have been extrapolated to speeds of less than 10 cm/s by both a linear and a quadratic relationship. Correlations between drift and wind speed in the Atlantic suggest that the linear law is a better approximation under realistic conditions. According to these measurements in the Atlantic the described buoy-drogue system with a windowshade drogue in 100-m depth is a good current-measuring device. Slippage is negligible for wind speeds of less than 15 m/s and is less than 2 cm/s under gale conditions. Undrogued buoys are strongly affected by wind and cannot be used for the analysis of currents without correction, even under light winds.
    Materialart: Article , PeerReviewed
    Format: text
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    facet.materialart.
    Unbekannt
    Edizioni ETS
    In:  In: Proceedings International Workshop Science education and guidance in schools: the way forward - 21-22 October 2013 Auditorium Sant’Apollonia, Florence, Italy. , ed. by Raschi, A., Di Fabio, A. and Sebastiani, L. Edizioni ETS, Florenz, Italy, pp. 283-289. ISBN 978-88-903469-2-7
    Publikationsdatum: 2019-09-23
    Beschreibung: The Collaborative Research Centre 754 (SFB 754) at GEOMAR in Kiel, Germany is an interdisciplinary research programme, which investigates the threats posed by ocean de-oxygenation and how this is coupled with climate change and the nutrient balance in the tropical oceans. The outreach component of SFB 754 has the task of producing videos with and for school pupils, in which different aspects of the science of the SFB are explained and introduced in a short and entertaining fashion. The goal is to attract pupils to sciences, both by the active involvement in the video production and by the consumption of the videos made by other pupils. So far more than 30 video clips were published on a dedicated website for viewing and download. The process of video production is enjoyable for all parties involved, but it is also time consuming and entails considerably more work for students and teachers, than normal lessons in class. As a result, the project now concentrates on dedicated summer schools and after-school activities as a platform for video production
    Materialart: Book chapter , NonPeerReviewed
    Format: text
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    facet.materialart.
    Unbekannt
    AGU (American Geophysical Union)
    In:  Geophysical Research Letters, 30 (2). p. 1050.
    Publikationsdatum: 2018-02-20
    Beschreibung: A high-resolution model of the North Atlantic Ocean is used to examine the potential of chlorofluorocarbon (CFC) inventories for calculating the rate of Labrador Sea Water (LSW) formation. While the simulated CFC-11 inventory and its geographical distribution in 1997 is fairly similar to observations, the model indicates pronounced variations in the history of CFC uptake, reflecting pulsations in LSW renewal in response to changes in wintertime atmospheric conditions. The LSW formation rate based on the volume of newly homogenized water during a winter season varies between 0 Sv and 11 Sv, and it is correlated (with a lag of 1 year) with the North Atlantic Oscillation (NAO) Index. The CFC-based estimate of the mean LSW formation rate is 3.5–4.4 Sv, approximately representing the mean volumetric formation rate (4.3 Sv) for the period 1970–1997.
    Materialart: Article , PeerReviewed
    Format: text
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    facet.materialart.
    Unbekannt
    AGU (American Geophysical Union)
    In:  Geophysical Research Letters, 33 (L21S08).
    Publikationsdatum: 2018-02-19
    Beschreibung: Direct observations at the Grand Banks have raised a quandary concerning the pathways of the lower branch of the meridional overturning circulation: In contrast to moored current meters that depict an intense, narrow Deep Western Boundary Current (DWBC), observations using different float types failed to show this continuous export path. Here, this issue is addressed by a Lagrangian analysis of synthetic particles in an eddy-resolving circulation model. Due to intense eddy activity around the Grand Banks, about 40% of the deep water in the DWBC is diverted into the interior, spreading southward along the western flank of the Mid-Atlantic Ridge or with the eddying flow field in the basin interior. Imposing constraints on the vertical displacements of particles similar to those experienced by observational floats further reduces their adherence to the DWBC, particularly near the southern tip of the Grand Banks.
    Materialart: Article , PeerReviewed
    Format: text
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 5
    facet.materialart.
    Unbekannt
    AGU (American Geophysical Union)
    In:  Geophysical Research Letters, 33 (L21S01).
    Publikationsdatum: 2018-02-19
    Beschreibung: Analyses of sea surface height (SSH) records based on satellite altimeter data and hydrographic properties have suggested a considerable weakening of the North Atlantic subpolar gyre during the 1990s. Here we report hindcast simulations with high-resolution ocean circulation models that demonstrate a close correspondence of the SSH changes with the volume transport of the boundary current system in the Labrador Sea. The 1990s-decline, of about 15% of the long-term mean, appears as part of a decadal variability of the gyre transport driven by changes in both heat flux and wind stress associated with the North Atlantic Oscillation (NAO). The changes in the subpolar gyre, as manifested in the deep western boundary current off Labrador, reverberate in the strength of the meridional overturning circulation (MOC) in the subtropical North Atlantic, suggesting the potential of a subpolar transport index as an element of a MOC monitoring system.
    Materialart: Article , PeerReviewed
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 6
    facet.materialart.
    Unbekannt
    AGU (American Geophysical Union)
    In:  Geophysical Research Letters, 96 (C4). pp. 7249-7263.
    Publikationsdatum: 2018-07-19
    Beschreibung: Drift behavior of drogued and undrogued Hermes‐type buoys is studied. After drogue loss, an increase in drift speed and acceleration is observed as well as improved correlations between drift and wind in both speed and direction. With these criteria, a method for the separation of large data sets into a drogued and an undrogued part has been developed. In most areas of the North Atlantic this works very well; problems arise in regions with strong surface currents and/or light winds. A statistical analysis is performed in a selected area to demonstrate the errors that can be caused by indiscriminate use of drogued and undrogued drifters. Mean and rms velocities as well as kinetic energies change significantly when undrogued buoys are considered. Therefore caution is essential when using surface drifters without drogues.
    Materialart: Article , PeerReviewed
    Format: text
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...