Articles | Volume 13, issue 2
https://doi.org/10.5194/os-13-235-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue:
https://doi.org/10.5194/os-13-235-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Validation of an ocean shelf model for the prediction of mixed-layer properties in the Mediterranean Sea west of Sardinia
Reiner Onken
CORRESPONDING AUTHOR
Helmholtz-Zentrum Geesthacht (HZG), Centre for Materials and Coastal Research, Max-Planck-Straße 1, 21502 Geesthacht, Germany
Related authors
Reiner Onken and Burkard Baschek
Ocean Sci. Discuss., https://doi.org/10.5194/os-2021-86, https://doi.org/10.5194/os-2021-86, 2021
Preprint withdrawn
Short summary
Short summary
The evolution of a small spiraliform ocean eddy is simulated with a numerical model. Its generation starts from a dense filament that is rolled into a vortex. Various quantities are organized in single-arm and multi-arm spirals. Oscillations of the vertical velocity are due to vortex Rossby waves. Virtual drifters and floats indicate downwelling everywhere near the surface, that is most intense in the center of the spiral, leading to a radial outflow and weak upwelling at the periphery.
Reiner Onken, Burkard Baschek, and Ingrid M. Angel-Benavides
Ocean Sci., 16, 657–684, https://doi.org/10.5194/os-16-657-2020, https://doi.org/10.5194/os-16-657-2020, 2020
Short summary
Short summary
In order to provide an aid for the interpretation of observations of
the formation, structure, and dynamics of submesoscale
patterns, a numerical model is applied in a double-offline-nested
setup to a sub-area of the Baltic Sea. A model with 500 m horizontal
resolution is nested into an existing operational model in order to
create a realistic mesoscale environment. Turbulent patterns with
horizontal scales < 1 km are resolved by a second nest with 100 m resolution.
Reiner Onken, Heinz-Volker Fiekas, Laurent Beguery, Ines Borrione, Andreas Funk, Michael Hemming, Jaime Hernandez-Lasheras, Karen J. Heywood, Jan Kaiser, Michaela Knoll, Baptiste Mourre, Paolo Oddo, Pierre-Marie Poulain, Bastien Y. Queste, Aniello Russo, Kiminori Shitashima, Martin Siderius, and Elizabeth Thorp Küsel
Ocean Sci., 14, 321–335, https://doi.org/10.5194/os-14-321-2018, https://doi.org/10.5194/os-14-321-2018, 2018
Short summary
Short summary
In June 2014, high-resolution oceanographic data were collected in the
western Mediterranean Sea by two research vessels, 11 gliders, moored
instruments, drifters, and one profiling float. The objective
of this article is to provide an overview of the data set which
is utilised by various ongoing studies, focusing on (i) water masses and circulation, (ii) operational forecasting, (iii) data assimilation, (iv) variability of the ocean, and (v) new payloads
for gliders.
Reiner Onken
Ocean Sci., 13, 925–945, https://doi.org/10.5194/os-13-925-2017, https://doi.org/10.5194/os-13-925-2017, 2017
Short summary
Short summary
An ocean prediction model was driven by observations via
assimilation. The best forecast was obtained using a smoothing scale
of 12.5 km and a time window of 24 h for data selection. Mostly,
the forecasts were better than that of a run without assimilation, the
skill score increased with increasing forecast range, and the score
for temperature was higher than the score for salinity. It is shown
that a vast number of data can be managed by the applied method
without data reduction.
Michaela Knoll, Ines Borrione, Heinz-Volker Fiekas, Andreas Funk, Michael P. Hemming, Jan Kaiser, Reiner Onken, Bastien Queste, and Aniello Russo
Ocean Sci., 13, 889–904, https://doi.org/10.5194/os-13-889-2017, https://doi.org/10.5194/os-13-889-2017, 2017
Short summary
Short summary
The hydrography and circulation west of Sardinia, observed in June 2014 during REP14-MED by means of various measuring platforms, are presented and compared with previous knowledge. So far, the circulation of this area is not well-known and the hydrography is subject to long-term changes. The different water masses are characterized and temporal changes are emphasized. The observed eddies are specified and geostrophic transports in the upper ocean are presented.
Michael P. Hemming, Jan Kaiser, Karen J. Heywood, Dorothee C.E. Bakker, Jacqueline Boutin, Kiminori Shitashima, Gareth Lee, Oliver Legge, and Reiner Onken
Ocean Sci., 13, 427–442, https://doi.org/10.5194/os-13-427-2017, https://doi.org/10.5194/os-13-427-2017, 2017
Short summary
Short summary
Underwater gliders are useful platforms for monitoring the world oceans at a high resolution. An experimental pH sensor was attached to an underwater glider in the Mediterranean Sea, which is an important carbon sink region. Comparing measurements from the glider with those obtained from a ship indicated that there were issues with the experimental pH sensor. Correcting for these issues enabled us to look at pH variability in the area related to biomass abundance and physical water properties.
Paolo Oddo, Andrea Storto, Srdjan Dobricic, Aniello Russo, Craig Lewis, Reiner Onken, and Emanuel Coelho
Ocean Sci., 12, 1137–1153, https://doi.org/10.5194/os-12-1137-2016, https://doi.org/10.5194/os-12-1137-2016, 2016
Reiner Onken and Burkard Baschek
Ocean Sci. Discuss., https://doi.org/10.5194/os-2021-86, https://doi.org/10.5194/os-2021-86, 2021
Preprint withdrawn
Short summary
Short summary
The evolution of a small spiraliform ocean eddy is simulated with a numerical model. Its generation starts from a dense filament that is rolled into a vortex. Various quantities are organized in single-arm and multi-arm spirals. Oscillations of the vertical velocity are due to vortex Rossby waves. Virtual drifters and floats indicate downwelling everywhere near the surface, that is most intense in the center of the spiral, leading to a radial outflow and weak upwelling at the periphery.
Reiner Onken, Burkard Baschek, and Ingrid M. Angel-Benavides
Ocean Sci., 16, 657–684, https://doi.org/10.5194/os-16-657-2020, https://doi.org/10.5194/os-16-657-2020, 2020
Short summary
Short summary
In order to provide an aid for the interpretation of observations of
the formation, structure, and dynamics of submesoscale
patterns, a numerical model is applied in a double-offline-nested
setup to a sub-area of the Baltic Sea. A model with 500 m horizontal
resolution is nested into an existing operational model in order to
create a realistic mesoscale environment. Turbulent patterns with
horizontal scales < 1 km are resolved by a second nest with 100 m resolution.
Reiner Onken, Heinz-Volker Fiekas, Laurent Beguery, Ines Borrione, Andreas Funk, Michael Hemming, Jaime Hernandez-Lasheras, Karen J. Heywood, Jan Kaiser, Michaela Knoll, Baptiste Mourre, Paolo Oddo, Pierre-Marie Poulain, Bastien Y. Queste, Aniello Russo, Kiminori Shitashima, Martin Siderius, and Elizabeth Thorp Küsel
Ocean Sci., 14, 321–335, https://doi.org/10.5194/os-14-321-2018, https://doi.org/10.5194/os-14-321-2018, 2018
Short summary
Short summary
In June 2014, high-resolution oceanographic data were collected in the
western Mediterranean Sea by two research vessels, 11 gliders, moored
instruments, drifters, and one profiling float. The objective
of this article is to provide an overview of the data set which
is utilised by various ongoing studies, focusing on (i) water masses and circulation, (ii) operational forecasting, (iii) data assimilation, (iv) variability of the ocean, and (v) new payloads
for gliders.
Reiner Onken
Ocean Sci., 13, 925–945, https://doi.org/10.5194/os-13-925-2017, https://doi.org/10.5194/os-13-925-2017, 2017
Short summary
Short summary
An ocean prediction model was driven by observations via
assimilation. The best forecast was obtained using a smoothing scale
of 12.5 km and a time window of 24 h for data selection. Mostly,
the forecasts were better than that of a run without assimilation, the
skill score increased with increasing forecast range, and the score
for temperature was higher than the score for salinity. It is shown
that a vast number of data can be managed by the applied method
without data reduction.
Michaela Knoll, Ines Borrione, Heinz-Volker Fiekas, Andreas Funk, Michael P. Hemming, Jan Kaiser, Reiner Onken, Bastien Queste, and Aniello Russo
Ocean Sci., 13, 889–904, https://doi.org/10.5194/os-13-889-2017, https://doi.org/10.5194/os-13-889-2017, 2017
Short summary
Short summary
The hydrography and circulation west of Sardinia, observed in June 2014 during REP14-MED by means of various measuring platforms, are presented and compared with previous knowledge. So far, the circulation of this area is not well-known and the hydrography is subject to long-term changes. The different water masses are characterized and temporal changes are emphasized. The observed eddies are specified and geostrophic transports in the upper ocean are presented.
Michael P. Hemming, Jan Kaiser, Karen J. Heywood, Dorothee C.E. Bakker, Jacqueline Boutin, Kiminori Shitashima, Gareth Lee, Oliver Legge, and Reiner Onken
Ocean Sci., 13, 427–442, https://doi.org/10.5194/os-13-427-2017, https://doi.org/10.5194/os-13-427-2017, 2017
Short summary
Short summary
Underwater gliders are useful platforms for monitoring the world oceans at a high resolution. An experimental pH sensor was attached to an underwater glider in the Mediterranean Sea, which is an important carbon sink region. Comparing measurements from the glider with those obtained from a ship indicated that there were issues with the experimental pH sensor. Correcting for these issues enabled us to look at pH variability in the area related to biomass abundance and physical water properties.
Paolo Oddo, Andrea Storto, Srdjan Dobricic, Aniello Russo, Craig Lewis, Reiner Onken, and Emanuel Coelho
Ocean Sci., 12, 1137–1153, https://doi.org/10.5194/os-12-1137-2016, https://doi.org/10.5194/os-12-1137-2016, 2016
Related subject area
Approach: Numerical Models | Depth range: Shelf-sea depth | Geographical range: Mediterranean Sea | Phenomena: Temperature, Salinity and Density Fields
Modeling the ocean and atmosphere during an extreme bora event in northern Adriatic using one-way and two-way atmosphere–ocean coupling
M. Ličer, P. Smerkol, A. Fettich, M. Ravdas, A. Papapostolou, A. Mantziafou, B. Strajnar, J. Cedilnik, M. Jeromel, J. Jerman, S. Petan, V. Malačič, and S. Sofianos
Ocean Sci., 12, 71–86, https://doi.org/10.5194/os-12-71-2016, https://doi.org/10.5194/os-12-71-2016, 2016
Short summary
Short summary
We compare the northern Adriatic response to an extreme bora event, as simulated by one-way and two-way (i.e. with ocean feedback to the atmosphere) atmosphere-ocean coupling. We show that two-way coupling yields significantly better estimates of heat fluxes, most notably sensible heat flux, across the air-sea interface. When compared to observations in the northern Adriatic, two-way coupled system consequently leads to a better representation of ocean temperatures throughout the event.
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Short summary
A numerical ocean circulation model has been employed to explore the
sensitivity of the forecast skill of mixed-layer properties to the
initial conditions, boundary conditions, and vertical mixing
parameterisations. All forecasts were validated against observations
which were taken in June 2014 to the west of Sardinia.
A numerical ocean circulation model has been employed to explore the
sensitivity of the...