Surface-Active Properties of the Sea Surface Microlayerand Consequences for Pollution in the Mediterranean Sea

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.

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New Evidence of Mediterranean Climate Change and Variability from Sea Surface Temperature Observations

Remote Sensing ◽

10.3390/rs12010132 ◽

2020 ◽

Vol 12 (1) ◽

pp. 132 ◽

Cited By ~ 9

Author(s):

Andrea Pisano ◽

Salvatore Marullo ◽

Vincenzo Artale ◽

Federico Falcini ◽

Chunxue Yang ◽

...

Keyword(s):

Climate Change ◽

Surface Temperature ◽

Sea Surface Temperature ◽

Mediterranean Sea ◽

Sea Surface ◽

Western Basin ◽

Mean Values ◽

The Mediterranean ◽

The Impact ◽

Northeastern Atlantic

Estimating long-term modifications of the sea surface temperature (SST) is crucial for evaluating the current state of the oceans and to correctly assess the impact of climate change at regional scales. In this work, we analyze SST variations within the Mediterranean Sea and the adjacent Northeastern Atlantic box (west of the Strait of Gibraltar) over the last 37 years, by using a satellite-based dataset from the Copernicus Marine Environment Monitoring Service (CMEMS). We found a mean warming trend of 0.041 ± 0.006 ∘ C/year over the whole Mediterranean Sea from 1982 to 2018. The trend has an uneven spatial pattern, with values increasing from 0.036 ± 0.006 ∘ C/year in the western basin to 0.048 ± 0.006 ∘ C/year in the Levantine–Aegean basin. The Northeastern Atlantic box and the Mediterranean show a similar trend until the late 1990s. Afterwards, the Mediterranean SST continues to increase, whereas the Northeastern Atlantic box shows no significant trend, until ~2015. The observed change in the Mediterranean Sea affects not only the mean trend but also the amplitude of the Mediterranean seasonal signal, with consistent relative increase and decrease of summer and winter mean values, respectively, over the period considered. The analysis of SST changes occurred during the “satellite era” is further complemented by reconstructions also based on direct in situ SST measurements, i.e., the Extended Reconstructed SST (ERSST) and the Hadley Centre Sea Ice and Sea Surface Temperature dataset (HadISST), which go back to the 19th century. The analysis of these longer time series, covering the last 165 years, indicates that the increasing Mediterranean trend, observed during the CMEMS operational period, is consistent with the Atlantic Multidecadal Oscillation (AMO), as it closely follows the last increasing period of AMO. This coincidence occurs at least until 2007, when the apparent onset of the decreasing phase of AMO is not seen in the Mediterranean SST evolution.

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Multi-Physics Ensemble versus Atmosphere–Ocean Coupled Model Simulations for a Tropical-Like Cyclone in the Mediterranean Sea

Atmosphere ◽

10.3390/atmos10040202 ◽

2019 ◽

Vol 10 (4) ◽

pp. 202 ◽

Cited By ~ 9

Author(s):

Antonio Ricchi ◽

Mario Marcello Miglietta ◽

Davide Bonaldo ◽

Guido Cioni ◽

Umberto Rizza ◽

...

Keyword(s):

High Resolution ◽

Mediterranean Sea ◽

Computational Cost ◽

Ocean Model ◽

Surface Fluxes ◽

Ocean Modeling ◽

Sea Surface ◽

Regional Ocean Modeling System ◽

The Mediterranean ◽

Physics Ensemble

Between 19 and 22 January 2014, a baroclinic wave moving eastward from the Atlantic Ocean generated a cut-off low over the Strait of Gibraltar and was responsible for the subsequent intensification of an extra-tropical cyclone. This system exhibited tropical-like features in the following stages of its life cycle and remained active for approximately 80 h, moving along the Mediterranean Sea from west to east, eventually reaching the Adriatic Sea. Two different modeling approaches, which are comparable in terms of computational cost, are analyzed here to represent the cyclone evolution. First, a multi-physics ensemble using different microphysics and turbulence parameterization schemes available in the WRF (weather research and forecasting) model is employed. Second, the COAWST (coupled ocean–atmosphere wave sediment transport modeling system) suite, including WRF as an atmospheric model, ROMS (regional ocean modeling system) as an ocean model, and SWAN (simulating waves in nearshore) as a wave model, is used. The advantage of using a coupled modeling system is evaluated taking into account air–sea interaction processes at growing levels of complexity. First, a high-resolution sea surface temperature (SST) field, updated every 6 h, is used to force a WRF model stand-alone atmospheric simulation. Later, a two-way atmosphere–ocean coupled configuration is employed using COAWST, where SST is updated using consistent sea surface fluxes in the atmospheric and ocean models. Results show that a 1D ocean model is able to reproduce the evolution of the cyclone rather well, given a high-resolution initial SST field produced by ROMS after a long spin-up time. Additionally, coupled simulations reproduce more accurate (less intense) sea surface heat fluxes and a cyclone track and intensity, compared with a multi-physics ensemble of standalone atmospheric simulations.

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Growth and Demography of the Solitary Scleractinian Coral Leptopsammia pruvoti along a Sea Surface Temperature Gradient in the Mediterranean Sea

PLoS ONE ◽

10.1371/journal.pone.0037848 ◽

2012 ◽

Vol 7 (6) ◽

pp. e37848 ◽

Cited By ~ 31

Author(s):

Erik Caroselli ◽

Francesco Zaccanti ◽

Guido Mattioli ◽

Giuseppe Falini ◽

Oren Levy ◽

...

Keyword(s):

Temperature Gradient ◽

Surface Temperature ◽

Sea Surface Temperature ◽

Mediterranean Sea ◽

Scleractinian Coral ◽

Sea Surface ◽

Sea Surface Temperature Gradient ◽

The Mediterranean ◽

Surface Temperature Gradient

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SMOS-based estimation and validation of Total Alkalinity in the Mediterranean basin

10.5194/egusphere-egu2020-20753 ◽

2020 ◽

Author(s):

Roberto Sabia ◽

Estrella Olmedo ◽

Giampiero Cossarini ◽

Aida Alvera-Azcárate ◽

Veronica Gonzalez-Gambau ◽

...

Keyword(s):

Remote Sensing ◽

Mediterranean Sea ◽

Mediterranean Basin ◽

Sea Surface ◽

Sea Surface Salinity ◽

Total Alkalinity ◽

Surface Salinity ◽

Carbonate System ◽

The Mediterranean ◽

The Mediterranean Basin

ESA SMOS satellite [1] has been providing first-ever Sea Surface Salinity (SSS) measurements from space for over a decade now. Until recently, inherent algorithm limitations or external interferences hampered a reliable provision of satellite SSS data in semi-enclosed basin such as the Mediterranean Sea. This has been however overcome through different strategies in the retrieval scheme and data filtering approach [2, 3]. This recent capability has been in turn used to infer the spatial and temporal distribution of Total Alkalinity (TA - a crucial parameter of the marine carbonate system) in the Mediterranean, exploiting basin-specific direct relationships existing between salinity and TA.Preliminary results [4] focused on the differences existing in several parameterizations [e.g, 5] relating these two variables, and how they vary over a seasonal to interannual timescale.Currently, to verify the consistency and accuracy of the derived products, these data are being validated against a proper ensemble of in-situ, climatology and model outputs within the Mediterranean basin. An error propagation exercise is also being planned to assess how uncertainties in the satellite data would translate into the final products accuracy.The resulting preliminary estimates of Alkalinity in the Mediterranean Sea will be linked to the overall carbonate system in the broader context of Ocean Acidification assessment and marine carbon cycle.References:[1] J. Font et al., "SMOS: The Challenging Sea Surface Salinity Measurement From Space," in Proceedings of the IEEE, vol. 98, no. 5, pp. 649-665, May 2010. doi: 10.1109/JPROC.2009.2033096[2] Olmedo, E., J. Martinez, A. Turiel, J. Ballabrera-Poy, and M. Portabella,&#160; &#8220;Debiased non-Bayesian retrieval: A novel approach to SMOS Sea Surface Salinity&#8221;. Remote Sensing of Environment 193, 103-126 (2017).[3] Alvera-Azc&#225;rate, A., A. Barth, G. Parard, J.-M. Beckers, Analysis of SMOS sea surface salinity data using DINEOF, In Remote Sensing of Environment, Volume 180, 2016, Pages 137-145, ISSN 0034-4257, https://doi.org/10.1016/j.rse.2016.02.044.[4] Sabia, R., E. Olmedo, G. Cossarini, A. Turiel, A. Alvera-Azc&#225;rate, J. Martinez, D. Fern&#225;ndez-Prieto, Satellite-driven preliminary estimates of Total Alkalinity in the Mediterranean basin, Geophysical Research Abstracts, Vol. 21, EGU2019-17605, EGU General Assembly 2019, Vienna, Austria, April 7-12, 2019.[5] Cossarini, G., Lazzari, P., and Solidoro, C.: Spatiotemporal variability of alkalinity in the Mediterranean Sea, Biogeosciences, 12, 1647-1658, https://doi.org/10.5194/bg-12-1647-2015, 2015.&#160;&#160;

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FIRST ACTIVITIES IN ACOUSTIC DETECTION OF PARTICLES IN UPV

International Journal of Modern Physics A ◽

10.1142/s0217751x06033519 ◽

2006 ◽

Vol 21 (supp01) ◽

pp. 137-141 ◽

Cited By ~ 4

Author(s):

M. ARDID ◽

J. RAMIS ◽

V. ESPINOSA ◽

J. A. MARTÍNEZ-MORA ◽

F. CAMARENA ◽

...

Keyword(s):

Mediterranean Sea ◽

Deep Water ◽

Research Group ◽

High Energy ◽

Sea Surface ◽

Acoustic Detection ◽

High Energy Neutrino ◽

Energy Neutrino ◽

The Mediterranean ◽

Surface Noise

The first activities related to acoustic detection of particles by DISAO research group in the Univesitat Politècnica de València are described. We are applying some techniques from physic, engineering and oceanographic acoustics to face the high energy neutrino underwater acoustic detection challenge. The work is focused mainly in two topics: design, characterization and calibration of hydrophones, and simulation of the propagation of the signal in the sea. We present also some examples for these two topics: piezoelectric modelling and transducer simulation, calibration of hydrophones using MLS signals, and evaluation of the contribution of the sea surface noise to the deep water noise in the Mediterranean Sea by means of simulations of propagation of sound.

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