The relation between air mass trajectories and the water isotope composition of rain in the Mediterranean Sea area

This study proposed different techniques to estimate the isotope composition (δ18O), salinity and temperature/potential temperature in the Mediterranean Sea using five different variables: (i–ii) geographic coordinates (Longitude, Latitude), (iii) year, (iv) month and (v) depth. Three kinds of models based on artificial neural network (ANN), random forest (RF) and support vector machine (SVM) were developed. According to the results, the random forest models presents the best prediction accuracy for the querying phase and can be used to predict the isotope composition (mean absolute percentage error (MAPE) around 4.98%), salinity (MAPE below 0.20%) and temperature (MAPE around 2.44%). These models could be useful for research works that require the use of past data for these variables.

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The Portuguese Man-of-war, One of The Most Dangerous Marine Species, Has Always Entered The Mediterranean Sea: Strandings, Sightings And Museum Collections

10.21203/rs.3.rs-828581/v1 ◽

2021 ◽

Author(s):

Rosario Badalamenti ◽

Francesco Tiralongo ◽

Vincenzo Arizza ◽

Sabrina Lo Brutto

Keyword(s):

Mediterranean Sea ◽

Grey Literature ◽

Marine Species ◽

First Record ◽

Central Mediterranean ◽

Gulf Of Naples ◽

Tourism Sector ◽

The Mediterranean ◽

Sea Area ◽

Physalia Physalis

Abstract A search from different kinds of sources has been carried out to review the incidence of Physalia physalis, the Portuguese man-of-war, in the Mediterranean Sea; scientific and grey literature, social media, zoological museums were accessed. The records of the species were considered validated if documented with images or collected specimens. It was possible to date the putative first record of Physalia physalis in the Mediterranean Sea, thanks to a couple of colonies preserved in a historical collection, originating from the Gulf of Naples in 1914. Some massive strandings occurred in localities of the Alboran Sea, area of entrance from the Atlantic from where the species spread mainly along the Sicilian waters, in the central Mediterranean Sea. The records from the Italian maritime regions were then subdivided into three categories of risk according to the season of occurrence. These categories were created to assign a level of danger for swimmers to the sightings of Physalia physalis. The increasing sightings of such a poisonous organism in coastal waters can represent a risk to human health, and also to all those activities linked to the marine tourism sector. The involvement of citizens and touristic structures for the early detection of Physalia physalis can play a key role in preventing encounters with the species, allowing marine tourist facilities to operate within a range of reasonable security.

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Determination of the copper isotope composition of seawater revisited: A case study from the Mediterranean Sea

Chemical Geology ◽

10.1016/j.chemgeo.2018.09.009 ◽

2019 ◽

Vol 511 ◽

pp. 465-480 ◽

Cited By ~ 12

Author(s):

Isabelle Baconnais ◽

Olivier Rouxel ◽

Gabriel Dulaquais ◽

Marie Boye

Keyword(s):

Mediterranean Sea ◽

Isotope Composition ◽

Copper Isotope ◽

The Mediterranean

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The Relationship between Air-Mass Trajectories and the Abundance of Dust-Borne Prokaryotes at the SE Mediterranean Sea

Atmosphere ◽

10.3390/atmos10050280 ◽

2019 ◽

Vol 10 (5) ◽

pp. 280 ◽

Cited By ~ 3

Author(s):

Eyal Rahav ◽

Natalia Belkin ◽

Adina Paytan ◽

Barak Herut

Keyword(s):

Mediterranean Sea ◽

Temporal Variability ◽

Airborne Microorganisms ◽

Coastal Site ◽

Air Mass ◽

Dust Aerosols ◽

Air Mass Trajectories ◽

Airborne Microbes ◽

The Relationship ◽

Air Mass Trajectory

Airborne prokaryotes are transported along with dust/aerosols, yet very little attention is given to their temporal variability above the oceans and the factors that govern their abundance. We analyzed the abundance of autotrophic (cyanobacteria) and heterotopic airborne microbes in 34 sampling events between 2015–2018 at a coastal site in the SE Mediterranean Sea. We show that airborne autotrophic (0.2–7.6 cells × 103 m−3) and heterotrophic (0.2–30.6 cells × 103 m−3) abundances were affected by the origin and air mass trajectory, and the concentration of dust/aerosols in the air, while seasonality was not coherent. The averaged ratio between heterotrophic and autotrophic prokaryotes in marine-dominated trajectories was ~1.7 ± 0.6, significantly lower than for terrestrial routes (6.8 ± 6.1). Airborne prokaryotic abundances were linearly and positively correlated to the concentrations of total aerosol, while negatively correlated with the aerosol’s anthropogenic fraction (using Pb/Al or Cu/Al ratios as proxies). While aerosols may play a major role in dispersing terrestrial and marine airborne microbes in the SE Mediterranean Sea, the mechanisms involved in the dispersal and diversity of airborne microorganisms remain to be studied and should include standardization in collection and analysis protocols.

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Stable lead isotope tracers of air mass trajectories in the Mediterranean region

Nature ◽

10.1038/330154a0 ◽

1987 ◽

Vol 330 (6144) ◽

pp. 154-156 ◽

Cited By ~ 87

Author(s):

Hal Maring ◽

Dorothy M. Settle ◽

Patrick Buat-Ménard ◽

François Dulac ◽

Clair C. Patterson

Keyword(s):

Mediterranean Region ◽

Lead Isotope ◽

Air Mass ◽

Isotope Tracers ◽

Air Mass Trajectories ◽

The Mediterranean

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Isotope composition of air moisture over the Mediterranean Sea: an index of the air-sea interaction pattern

Tellus B ◽

10.1034/j.1600-0889.2003.00081.x ◽

2003 ◽

Vol 55 (5) ◽

pp. 953-965 ◽

Cited By ~ 163

Author(s):

J. R. GAT ◽

B. KLEIN ◽

Y. KUSHNIR ◽

W. ROETHER ◽

H. WERNLI ◽

...

Keyword(s):

Mediterranean Sea ◽

Isotope Composition ◽

Interaction Pattern ◽

The Mediterranean

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Atmospheric occurrence, transport and deposition of polychlorinated biphenyls and hexachlorobenzene in the Mediterranean and Black Seas

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-14-9747-2014 ◽

2014 ◽

Vol 14 (7) ◽

pp. 9747-9781 ◽

Cited By ~ 2

Author(s):

N. Berrojalbiz ◽

J. Castro-Jiménez ◽

G. Mariani ◽

J. Wollgast ◽

G. Hanke ◽

...

Keyword(s):

Polychlorinated Biphenyls ◽

Mediterranean Sea ◽

Gas Phase ◽

Oh Radicals ◽

Anthropogenic Pressures ◽

Air Mass ◽

The Mediterranean ◽

Water Equilibrium ◽

Mediterranean And Black Seas ◽

Atmospheric Concentrations

Abstract. The Mediterranean and Black Seas are unique marine environments subject to important anthropogenic pressures due to direct and indirect loads of atmospheric inputs of organochlorine compounds (OCl) from primary and secondary sources. Here we report the results obtained during two east-west sampling cruises in June 2006 and May 2007 from Barcelona to Istanbul and Alexandria, respectively, where gas phase and aerosol samples were collected. Both matrices were analyzed for 41 polychlorinated biphenyls (PCBs), including dioxin-like congeners, and hexachlorobencene (HCB). The values reported in this study for gas phase HCB and ∑41PCB (LOD to 418.3 pg m−3 and from 81.99 to 931.6 pg m−3 respectively) are in the same range of those reported in former studies, possibly suggesting a limited decline in their atmospheric concentrations during the last decade for the Mediterranean region due to land base OCl sources. There is a clear influence of the direction of the air-mass on the atmospheric concentrations of PCBs, with higher concentrations when the air mass was from southern Europe, and the lowest concentrations for air masses coming from the SW Mediterranean and Atlantic Ocean. PCBs and HCB are close to air–water equilibrium for most sampling periods, thus resulting in low atmospheric deposition fluxes at open sea. This is consistent with the oligotrophic character of the Mediterranean Sea with a small influence of the biological pump capturing atmospheric PCBs. Therefore, degradation of gas-phase PCBs by OH radicals is estimated to be the main loss process of atmospheric PCBs during their transport over the Mediterranean Sea. Conversely, atmospheric residence times of HCB are predicted to be very long due to a lack of atmospheric degradation and low depositional fluxes due to concentrations at air–water equilibrium.

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