Articles | Volume 12, issue 5
https://doi.org/10.5194/os-12-1137-2016
© Author(s) 2016. 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-12-1137-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
14 Oct 2016
Research article |
| 14 Oct 2016
A hybrid variational-ensemble data assimilation scheme with systematic error correction for limited-area ocean models
Paolo Oddo
CORRESPONDING AUTHOR
NATO Science and Technology Organization, Centre for Maritime Research and Experimentation,
Viale San Bartolomeo 400, 19126 La Spezia, Italy
Andrea Storto
Euro-Mediterranean Centre for Climate Change (CMCC), via Franceschini 31, 40128 Bologna, Italy
Srdjan Dobricic
European Commission, Joint Research Centre, Via Enrico Fermi 2749, 21027 Ispra (VA), Italy
Aniello Russo
NATO Science and Technology Organization, Centre for Maritime Research and Experimentation,
Viale San Bartolomeo 400, 19126 La Spezia, Italy
Craig Lewis
NATO Science and Technology Organization, Centre for Maritime Research and Experimentation,
Viale San Bartolomeo 400, 19126 La Spezia, Italy
Reiner Onken
NATO Science and Technology Organization, Centre for Maritime Research and Experimentation,
Viale San Bartolomeo 400, 19126 La Spezia, Italy
Emanuel Coelho
NATO Science and Technology Organization, Centre for Maritime Research and Experimentation,
Viale San Bartolomeo 400, 19126 La Spezia, Italy
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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
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In June 2014, high-resolution oceanographic data were collected in the
western Mediterranean Sea by two research vessels, 11 gliders, moored
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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.
Ivan Federico, Nadia Pinardi, Giovanni Coppini, Paolo Oddo, Rita Lecci, and Michele Mossa
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Jenny Pistoia, Nadia Pinardi, Paolo Oddo, Matthew Collins, Gerasimos Korres, and Yann Drillet
Nat. Hazards Earth Syst. Sci., 16, 1807–1819, https://doi.org/10.5194/nhess-16-1807-2016, https://doi.org/10.5194/nhess-16-1807-2016, 2016
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In this work we developed a new multi-model super-ensemble method to estimate sea surface temperature, an important product of ocean analysis systems. We find that ensemble size, quality, type of members and the training period length are all important elements of the MMSE methodology and require careful calibration. We show that with a rather limited but overconfident data set (with a low bias of the starting ensemble members) the RMSE analysis can be improved.
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Geosci. Model Dev., 9, 1597–1625, https://doi.org/10.5194/gmd-9-1597-2016, https://doi.org/10.5194/gmd-9-1597-2016, 2016
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VISIR is a new numerical model for the computation of optimal ship routes from meteo-marine forecasts. VISIR offers the scientific community an open platform whereby various ideas and methods for ship route optimization can be shared, tested, and compared to each other.
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Andrea Storto, Giulia Chierici, Julia Pfeffer, Anne Barnoud, Romain Bourdalle-Badie, Alejandro Blazquez, Davide Cavaliere, Benjamin Coupry, Marie Drevillon, Sebastien Fourest, Gilles Larnicol, and Chunxue Yang
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Andrea Storto, Yassmin Hesham Essa, Vincenzo de Toma, Alessandro Anav, Gianmaria Sannino, Rosalia Santoleri, and Chunxue Yang
Geosci. Model Dev., 16, 4811–4833, https://doi.org/10.5194/gmd-16-4811-2023, https://doi.org/10.5194/gmd-16-4811-2023, 2023
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Regional climate models are a fundamental tool for a very large number of applications and are being increasingly used within climate services, together with other complementary approaches. Here, we introduce a new regional coupled model, intended to be later extended to a full Earth system model, for climate investigations within the Mediterranean region, coupled data assimilation experiments, and several downscaling exercises (reanalyses and long-range predictions).
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
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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
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In order to provide an aid for the interpretation of observations of
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patterns, a numerical model is applied in a double-offline-nested
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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.
Eric Jansen, Sam Pimentel, Wang-Hung Tse, Dimitra Denaxa, Gerasimos Korres, Isabelle Mirouze, and Andrea Storto
Ocean Sci., 15, 1023–1032, https://doi.org/10.5194/os-15-1023-2019, https://doi.org/10.5194/os-15-1023-2019, 2019
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Gerasimos Korres, Dimitra Denaxa, Eric Jansen, Isabelle Mirouze, Sam Pimentel, Wang-Hung Tse, and Andrea Storto
Ocean Sci. Discuss., https://doi.org/10.5194/os-2018-158, https://doi.org/10.5194/os-2018-158, 2019
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A statistical-dynamical observation operator (SOSSTA) for satellite SST data assimilation able to account for SST diurnal variability, is formulated and implemented into the POSEIDON forecasting system (Aegean Sea). Model experiments where daytime SST retrievals from the SEVIRI infrared radiometer are introduced into the data assimilation procedure through the application of the observation operator, showed an improvement of the POSEIDON modelling system performance.
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
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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
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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.
Marianne Pietschnig, Michael Mayer, Takamasa Tsubouchi, Andrea Storto, Sebastian Stichelberger, and Leopold Haimberger
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Revised manuscript not accepted
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Reiner Onken
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An ocean prediction model was driven by observations via
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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
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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
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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.
Reiner Onken
Ocean Sci., 13, 235–257, https://doi.org/10.5194/os-13-235-2017, https://doi.org/10.5194/os-13-235-2017, 2017
Short summary
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.
Ivan Federico, Nadia Pinardi, Giovanni Coppini, Paolo Oddo, Rita Lecci, and Michele Mossa
Nat. Hazards Earth Syst. Sci., 17, 45–59, https://doi.org/10.5194/nhess-17-45-2017, https://doi.org/10.5194/nhess-17-45-2017, 2017
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SANIFS (Southern Adriatic Northern Ionian coastal Forecasting System) is a coastal-ocean operational system based on the unstructured grid finite-element three-dimensional hydrodynamic SHYFEM model, which provides short-term forecasts. The operational chain is based on a downscaling approach starting from the large-scale system for the entire Mediterranean Basin (MFS, Mediterranean Forecasting System), which provides initial and boundary condition fields for the nested system.
Zhaoyi Wang, Andrea Storto, Nadia Pinardi, Guimei Liu, and Hui Wang
Nat. Hazards Earth Syst. Sci., 17, 17–30, https://doi.org/10.5194/nhess-17-17-2017, https://doi.org/10.5194/nhess-17-17-2017, 2017
Andrea Storto and Simona Masina
Earth Syst. Sci. Data, 8, 679–696, https://doi.org/10.5194/essd-8-679-2016, https://doi.org/10.5194/essd-8-679-2016, 2016
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A large number of applications related to the study of ocean climate require reliable datasets of the main physical variables of the ocean. Ocean reanalyses are a methodology based on the synthesis of information from ocean observations and models, and near-surface atmospheric observations into a dataset in a way as consistent in time as possible. In this paper, we describe and validate an upgraded version of the CMCC global ocean physical reanalysis (1980–present) at 1 / 4° resolution.
Doroteaciro Iovino, Simona Masina, Andrea Storto, Andrea Cipollone, and Vladimir N. Stepanov
Geosci. Model Dev., 9, 2665–2684, https://doi.org/10.5194/gmd-9-2665-2016, https://doi.org/10.5194/gmd-9-2665-2016, 2016
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An 11-year simulation of a global eddying ocean (1/16) configuration is presented. Model performance is evaluated against observations and a twin 1/4 configuration. The model realistically represents the variability at upper and intermediate depths, the position and strength of the surface circulation, and exchanges of mass through key passages. Sea ice properties are close to satellite observations. This simulation constitutes the groundwork for future applications to short range ocean forecasting.
Jenny Pistoia, Nadia Pinardi, Paolo Oddo, Matthew Collins, Gerasimos Korres, and Yann Drillet
Nat. Hazards Earth Syst. Sci., 16, 1807–1819, https://doi.org/10.5194/nhess-16-1807-2016, https://doi.org/10.5194/nhess-16-1807-2016, 2016
Short summary
Short summary
In this work we developed a new multi-model super-ensemble method to estimate sea surface temperature, an important product of ocean analysis systems. We find that ensemble size, quality, type of members and the training period length are all important elements of the MMSE methodology and require careful calibration. We show that with a rather limited but overconfident data set (with a low bias of the starting ensemble members) the RMSE analysis can be improved.
Daniel R. Hayes, Srdjan Dobricic, and Hezi Gildor
Ocean Sci. Discuss., https://doi.org/10.5194/os-2016-43, https://doi.org/10.5194/os-2016-43, 2016
Preprint retracted
Short summary
Short summary
This research has shown that it is possible to estimate ocean currents more accurately when using autonomous underwater glider observations of ocean temperature and salinity in conjunction with numerical ocean current models. This allows offshore activities to be more safely carried out, since currents can transport pollutants or disrupt operations in unpredictable ways. Using only models is not as reliable as using a merged result of observations and models, which can be done in near real time.
Gianandrea Mannarini, Nadia Pinardi, Giovanni Coppini, Paolo Oddo, and Alessandro Iafrati
Geosci. Model Dev., 9, 1597–1625, https://doi.org/10.5194/gmd-9-1597-2016, https://doi.org/10.5194/gmd-9-1597-2016, 2016
Short summary
Short summary
VISIR is a new numerical model for the computation of optimal ship routes from meteo-marine forecasts. VISIR offers the scientific community an open platform whereby various ideas and methods for ship route optimization can be shared, tested, and compared to each other.
V. E. Brando, F. Braga, L. Zaggia, C. Giardino, M. Bresciani, E. Matta, D. Bellafiore, C. Ferrarin, F. Maicu, A. Benetazzo, D. Bonaldo, F. M. Falcieri, A. Coluccelli, A. Russo, and S. Carniel
Ocean Sci., 11, 909–920, https://doi.org/10.5194/os-11-909-2015, https://doi.org/10.5194/os-11-909-2015, 2015
Short summary
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Sea surface temperature and turbidity, derived from satellite imagery, were used to characterize river plumes in the northern Adriatic Sea during a significant flood event in November 2014. Circulation patterns and sea surface salinity, from an operational coupled ocean-wave model, supported the interpretation of the plumes' interaction with the receiving waters and among them.
L. Visinelli, S. Masina, M. Vichi, and A. Storto
Biogeosciences Discuss., https://doi.org/10.5194/bgd-11-5399-2014, https://doi.org/10.5194/bgd-11-5399-2014, 2014
Revised manuscript not accepted
H. Mihanović, I. Vilibić, S. Carniel, M. Tudor, A. Russo, A. Bergamasco, N. Bubić, Z. Ljubešić, D. Viličić, A. Boldrin, V. Malačič, M. Celio, C. Comici, and F. Raicich
Ocean Sci., 9, 561–572, https://doi.org/10.5194/os-9-561-2013, https://doi.org/10.5194/os-9-561-2013, 2013
Related subject area
Approach: Data Assimilation | Depth range: All Depths | Geographical range: Mediterranean Sea | Phenomena: Temperature, Salinity and Density Fields
Upscaling of a local model into a larger-scale model
Dense CTD survey versus glider fleet sampling: comparing data assimilation performance in a regional ocean model west of Sardinia
Design and validation of MEDRYS, a Mediterranean Sea reanalysis over the period 1992–2013
Luc Vandenbulcke and Alexander Barth
Ocean Sci., 15, 291–305, https://doi.org/10.5194/os-15-291-2019, https://doi.org/10.5194/os-15-291-2019, 2019
Short summary
Short summary
In operational oceanography, regional and local models use large-scale models (such as those run by CMEMS) for their initial and/or boundary conditions, but unfortunately there is no feedback that improves the large-scale models. The present study aims at replacing normal two-way nesting by a data assimilation technique. This
upscalingmethod is tried out in the north-western Mediterranean Sea using the NEMO model and shows that the basin-scale model does indeed benefit from the nested model.
Jaime Hernandez-Lasheras and Baptiste Mourre
Ocean Sci., 14, 1069–1084, https://doi.org/10.5194/os-14-1069-2018, https://doi.org/10.5194/os-14-1069-2018, 2018
Short summary
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Different sampling strategies have been assessed in order to evaluate the most efficient configuration for the assimilation of high resolution measurements into a regional ocean model. The results show the capability of the model to ingest both large scale and high resolution observations and the improvement of the forecast fields. In particular, the configurations using eight gliders and the one assimilating CTDs show similar results and the give the best performance among all the simulations
Mathieu Hamon, Jonathan Beuvier, Samuel Somot, Jean-Michel Lellouche, Eric Greiner, Gabriel Jordà, Marie-Noëlle Bouin, Thomas Arsouze, Karine Béranger, Florence Sevault, Clotilde Dubois, Marie Drevillon, and Yann Drillet
Ocean Sci., 12, 577–599, https://doi.org/10.5194/os-12-577-2016, https://doi.org/10.5194/os-12-577-2016, 2016
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The paper describes MEDRYS, a MEDiterranean sea ReanalYsiS at high resolution for the period 1992–2013. The NEMOMED12 ocean model is forced at the surface by a new high resolution atmospheric forcing dataset (ALDERA). Altimeter data, satellite SST and temperature and salinity vertical profiles are jointly assimilated. The ability of the reanalysis to represent the sea surface high-frequency variability, water mass characteristics and transports through the Strait of Gibraltar is shown.
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