Reconstructing vertical profiles of geostrophic velocities from altimeter data: application to the Sicily Channel (Mediterranean Sea)

2004 ◽  
Author(s):  
Olga Cavalieri ◽  
Bruno Buongiorno Nardelli ◽  
Rosalia Santoleri
Keyword(s):  
Mediterranean Sea ◽  
Altimeter Data ◽  
Vertical Profiles ◽  
Data Application ◽  
Sicily Channel ◽  
Geostrophic Velocities

scholarly journals Seabed classification around Lampione islet, Pelagie Islands Marine Protected area, Sicily Channel, Mediterranean Sea

2019 ◽  
Vol 15 (2) ◽  
pp. 153-164 ◽  
Author(s):  
Sara Innangi ◽  
Gabriella Di Martino ◽  
Claudia Romagnoli ◽  
Renato Tonielli
Keyword(s):  
Mediterranean Sea ◽  
Protected Area ◽  
Marine Protected Area ◽  
Seabed Classification ◽  
Sicily Channel

The role of structural inheritance on Africa-Eurasia plate boundary evolution and neotectonics in the central Mediterranean sea

2021 ◽  
Author(s):  
Alina Polonia ◽  
Andrea Artoni ◽  
Graziella Barberi ◽  
Andrea Billi ◽  
Luca Gasperini ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Plate Boundary ◽  
Geophysical Data ◽  
Fault System ◽  
Central Mediterranean ◽  
Plate Convergence ◽  
Structural Inheritance ◽  
Central Mediterranean Sea ◽  
Sicily Channel ◽  
Subduction System

<p>Africa-Eurasia plate convergence and the retreat of the subducting slab led to the consumption of the Tethys ocean lithosphere, which has now mostly disappeared below or accreted/exhumed within the Alps/Apennines. Slab tearing plays a major role in plate boundary evolution, asthenospheric upwelling, dynamic topography and magmatism. However, the role played by structural inheritance on the Africa plate is not well constrained. Based on seismological, geodetic and marine geophysical data, we analyse the pattern of crustal deformation in the Calabrian Arc and Sicily Channel, two key regions to unravel the complex Africa/Eurasia plate interaction in the central Mediterranean Sea.</p><p>The Calabrian Arc subduction-rollback system accommodates Africa/Eurasia plate convergence along thrust faults developing both in the frontal and inner domains of the accretionary wedge. However, the most intriguing and tectonically active features are represented by arc-orthogonal faults deforming the subduction system along a complex strike-slip/transtensional pattern that may have been the source of major earthquakes in the Calabrian Arc. Deformation along the lithospheric transtensional faults is punctuated by buried sub-circular magnetized bodies aligned with Mt. Etna, that were interpreted as serpentinite/mud diapirs intruding the subduction system from the lower plate mantle. These faults are part of the overall dextral shear deformation, resulting from differences in Africa-Eurasia motion between the western and eastern sectors of the Tyrrhenian margin of northern Sicily, and accommodating diverging motions in the adjacent compartments of the Calabrian Arc. To the West, the Sicily Channel is part of the Pelagian block and experienced a lithospheric-scale continental rifting starting from the late Miocene with the development of NW-SE-trending tectonic depressions, bordered by crustal normal faults with variable throws. Our geophysical data, however, show that the most active tectonic feature in the area is a N-S trending and ~220-km-long lithospheric fault system characterized by volcanism, high heat flow and seismic activity. The NW-SE elongated rifting pattern, considered the first order structure in this region, appears currently inactive and sealed by undeformed Pleistocene deposits suggesting a recent change in structural development.</p><p>Seismological data show that the lithospheric boundaries present in the Calabrian Arc and Sicily Channel correlate well with spatial changes in the depth distribution of earthquakes and separate regions with different Moho depths and thickness of the seismogenic layer. We propose that these boundaries may represent long-lived inherited Mesozoic discontinuities controlling plate boundary evolution and neotectonics.</p>

scholarly journals Evaluation of global monitoring and forecasting systems at Mercator Océan

Ocean Science ◽  
2013 ◽  
Vol 9 (1) ◽  
pp. 57-81 ◽  
Author(s):  
J.-M. Lellouche ◽  
O. Le Galloudec ◽  
M. Drévillon ◽  
C. Régnier ◽  
E. Greiner ◽  
...  
Keyword(s):  
Quality Control ◽  
Sea Ice ◽  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Sea Surface ◽  
Altimeter Data ◽  
Open Boundary ◽  
Vertical Profiles ◽  
Validation Procedure

Abstract. Since December 2010, the MyOcean global analysis and forecasting system has consisted of the Mercator Océan NEMO global 1/4° configuration with a 1/12° nested model over the Atlantic and the Mediterranean. The open boundary data for the nested configuration come from the global 1/4° configuration at 20° S and 80° N. The data are assimilated by means of a reduced-order Kalman filter with a 3-D multivariate modal decomposition of the forecast error. It includes an adaptive-error estimate and a localization algorithm. A 3-D-Var scheme provides a correction for the slowly evolving large-scale biases in temperature and salinity. Altimeter data, satellite sea surface temperature and in situ temperature and salinity vertical profiles are jointly assimilated to estimate the initial conditions for numerical ocean forecasting. In addition to the quality control performed by data producers, the system carries out a proper quality control on temperature and salinity vertical profiles in order to minimise the risk of erroneous observed profiles being assimilated in the model. This paper describes the recent systems used by Mercator Océan and the validation procedure applied to current MyOcean systems as well as systems under development. The paper shows how refinements or adjustments to the system during the validation procedure affect its quality. Additionally, we show that quality checks (in situ, drifters) and data sources (satellite sea surface temperature) have as great an impact as the system design (model physics and assimilation parameters). The results of the scientific assessment are illustrated with diagnostics over the year 2010 mainly, assorted with time series over the 2007–2011 period. The validation procedure demonstrates the accuracy of MyOcean global products, whose quality is stable over time. All monitoring systems are close to altimetric observations with a forecast RMS difference of 7 cm. The update of the mean dynamic topography corrects local biases in the Indonesian Throughflow and in the western tropical Pacific. This improves also the subsurface currents at the Equator. The global systems give an accurate description of water masses almost everywhere. Between 0 and 500 m, departures from in situ observations rarely exceed 1 °C and 0.2 psu. The assimilation of an improved sea surface temperature product aims to better represent the sea ice concentration and the sea ice edge. The systems under development are still suffering from a drift which can only be detected by means of a 5-yr hindcast, preventing us from upgrading them in real time. This emphasizes the need to pursue research while building future systems for MyOcean2 forecasting.

scholarly journals A Synergetic Approach for the Space-Based Sea Surface Currents Retrieval in the Mediterranean Sea

2019 ◽  
Vol 11 (11) ◽  
pp. 1285 ◽  
Author(s):  
Daniele Ciani ◽  
Marie-Hélène Rio ◽  
Milena Menna ◽  
Rosalia Santoleri
Keyword(s):  
Numerical Model ◽  
Mediterranean Sea ◽  
Mediterranean Area ◽  
Hf Radar ◽  
Sea Surface ◽  
Reconstruction Method ◽  
Surface Currents ◽  
Basin Scale ◽  
The Mediterranean ◽  
Sicily Channel

We present a method for the remote retrieval of the sea surface currents in the Mediterranean Sea. Combining the altimeter-derived currents with sea-surface temperature information, we created daily, gap-free high resolution maps of sea surface currents for the period 2012–2016. The quality of the new multi-sensor currents has been assessed through comparisons to other surface-currents estimates, as the ones obtained from drifting buoys trajectories (at the basin scale), or HF-Radar platforms and ocean numerical model outputs in the Malta–Sicily Channel. The study yielded that our synergetic approach can improve the present-day derivation of the surface currents in the Mediterranean area up to 30% locally, with better performances for the the meridional component of the motion and in the western section of the basin. The proposed reconstruction method also showed satisfying performances in the retrieval of the ageostrophic circulation in the Sicily Channel. In this area, assuming the High Frequency Radar-derived currents as reference, the merged multi-sensor currents exhibited improvements with respect to the altimeter estimates and numerical model outputs, mainly due to their enhanced spatial and temporal resolution.

scholarly journals Holocene millennial-scale productivity variations in the Sicily Channel (Mediterranean Sea)

2008 ◽  
Vol 23 (3) ◽  
pp. n/a-n/a ◽  
Author(s):  
Alessandro Incarbona ◽  
Enrico Di Stefano ◽  
Bernardo Patti ◽  
Nicola Pelosi ◽  
Sergio Bonomo ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Sicily Channel ◽  
Millennial Scale
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