scholarly journals The transient distributions of nuclear weapon-generated tritium and its decay product <sup>3</sup> He in the Mediterranean Sea, 1952–2011, and their oceanographic potential

Ocean Science ◽  
2013 ◽  
Vol 9 (5) ◽  
pp. 837-854 ◽  
Author(s):  
W. Roether ◽  
P. Jean-Baptiste ◽  
E. Fourré ◽  
J. Sültenfuß
Keyword(s):  
Mediterranean Sea ◽  
Transit Time ◽  
Nuclear Weapon ◽  
Eastern Mediterranean ◽  
Decay Product ◽  
Intermediate Water ◽  
Tyrrhenian Sea ◽  
Transit Times ◽  
Time Dispersion ◽  
The Mediterranean

Abstract. We present a comprehensive account of tritium and 3He in the Mediterranean Sea since the appearance of the tritium generated by the atmospheric nuclear-weapon testing in the 1950s and early 1960s, based on essentially all available observations. Tritium in surface waters rose to 20–30 TU in 1964 (TU = 1018 × [3H]/H]), a factor of about 100 above the natural level, and thereafter declined 30-fold up to 2011. The decline was largely due to radioactive tritium decay, which produced significant amounts of its stable daughter 3He. We present the scheme by which we separate the tritiugenic part of 3He and the part due to release from the sea floor (terrigenic part). We show that the tritiugenic component can be quantified throughout the Mediterranean waters, typically to a ± 0.15 TU equivalent, mostly because the terrigenic part is low in 3He. This fact makes the Mediterranean unique in offering a potential for the use of tritiugenic 3He as a tracer. The transient distributions of the two tracers are illustrated by a number of sections spanning the entire sea and relevant features of their distributions are noted. By 2011, the 3He concentrations in the top few hundred metres had become low, in response to the decreasing tritium concentrations combined with a flushing out by the general westward drift of these waters. Tritium-3He ages in Levantine Intermediate Water (LIW) were obtained repeated in time at different locations, defining transit times from the LIW source region east of Rhodes. The ages show an upward trend with the time elapsed since the surface-water tritium maximum, which arises because the repeated observations represent increasingly slower moving parts of the full transit time spectrum of LIW. The transit time dispersion revealed by this new application of tritium-3He dating is considerable. We find mean transit times of 12 ± 2 yr up to the Strait of Sicily, 18 ± 3 yr up to the Tyrrhenian Sea, and 22 ± 4 yr up into the Western Mediterranean. Furthermore, we present full Eastern Mediterranean sections of terrigenic 3He and tritium-3He age in 1987, the latter one similarly showing an effect of the transit time dispersion. We conclude that the available tritium and 3He data, particularly if combined with other tracer data, are useful for constraining the subsurface circulation and mixing of the Mediterranean Sea.

scholarly journals The transient distributions of nuclear weapon-generated tritium and its decay product <sup>3</sup>He in the Mediterranean Sea, 1952–2011, and their oceanographic potential

2013 ◽  
Vol 10 (2) ◽  
pp. 649-690 ◽  
Author(s):  
W. Roether ◽  
P. Jean-Baptiste ◽  
E. Fourré ◽  
J. Sültenfuß
Keyword(s):  
Mediterranean Sea ◽  
Transit Time ◽  
Nuclear Weapon ◽  
Eastern Mediterranean ◽  
Decay Product ◽  
Intermediate Water ◽  
Tyrrhenian Sea ◽  
Transit Times ◽  
Time Dispersion ◽  
The Mediterranean

Abstract. We present a comprehensive account of tritium and 3He in the Mediterranean Sea since the appearance of the tritium generated by the atmospheric nuclear-weapon testing in the 1950's and early 1960's, based on essentially all available observations. Tritium in surface waters rose to 20–30 TU in 1964 (TU = 1018 · [3H]/[H]), a factor of about 100 above the natural level, and thereafter declined 30-fold up to 2011. The decline was largely due to radioactive tritium decay, which produced significant amounts of its stable daughter 3He. We present the scheme by which we separate the tritiugenic part of 3He and the part due to release from the sea floor (terrigenic part). We show that the tritiugenic component can be quantified throughout the Mediterranean waters, typically to a &amp;pm;0.15 TU equivalent, mostly because the terrigenic part is low in 3He. This fact makes the Mediterranean unique in offering a potential for the use of tritiugenic 3He as a tracer. The transient distributions of the two tracers are illustrated by a number of sections spanning the entire sea and relevant features of their distributions are noted. By 2011, the 3He concentrations in the top few hundred meters had become low, in response to the decreasing tritium concentrations combined with a flushing out by the general westward drift of these waters. Tritium-3He ages in Levantine Intermediate Water (LIW) were obtained repeated in time at different locations, defining transit times from the LIW source region east of Rhodes. The ages show an upward trend with the time elapsed since the surface-water tritium maximum, which arises because the repeated observations represent increasingly slower moving parts of the full transit time spectrum of LIW. The transit time dispersion found by this new application of tritium-3He dating is considerable. We find mean transit times of 12 &amp;pm; 2 yr up to the Strait of Sicily, 18 &amp;pm; 3 yr up to the Tyrrhenian Sea, and 22 &amp;pm; 4 yr up into the Western Mediterranean. We furthermore present full Eastern Mediterranean sections of terrigenic 3He and tritium-3He age in 1987, the latter one similarly showing an effect of the transit time dispersion. We conclude that the available tritium and 3He data, in particular if combined with other tracer data, are useful for constraining the subsurface circulation and mixing of the Mediterranean Sea.

scholarly journals New records of amphipod crustaceans along the Israeli Mediterranean coast, including a rare Mediterranean endemic species, Maera schieckei Karaman & Ruffo, 1971

2020 ◽  
Vol 8 ◽  
Author(s):  
Sabrina Lo Brutto ◽  
Davide Iaciofano
Keyword(s):  
Mediterranean Sea ◽  
Mediterranean Basin ◽  
Eastern Mediterranean ◽  
Aegean Sea ◽  
Western Mediterranean ◽  
Mediterranean Coast ◽  
Tyrrhenian Sea ◽  
Western Mediterranean Basin ◽  
The Mediterranean ◽  
Distribution And Ecology

A survey has been carried out at four Israeli rocky sites to evaluate the diversity of the amphipod fauna on various hard substrates, still scarcely monitored, as potential pabulum for amphipod crustacean species. A survey of shallow rocky reefs along the Mediterranean coast of Israel recovered 28 species and integrated the Amphipoda checklist for the country ofIsrael with 12 newly-recorded species. Such renewed national list includes Maera schieckei Karaman &amp; Ruffo, 1971, a rare species endemic to the Mediterranean Sea, recorded here for the first time from the southern Levant Basin. The species, described from specimens collected in the Tyrrhenian Sea in 1970, has been only recorded eight times within the whole Mediterranean Sea. A revision of the bibliography on the distribution and ecology of M. schieckei showed that, although mentioned only for the western Mediterranean basin by some authors, it is listed in the checklist of amphipods of the Aegean Sea and neighbouring seas and has been found in the eastern Mediterranean basin since 1978. Maera schieckei was rarely found in the Mediterranean, one of the most studied marine biogeographic region as concerns the amphipod fauna; and the species seems to prefer bays or gulf areas. The role of updating and monitoring faunal composition should be re-evaluated.

scholarly journals Hydrography in the Mediterranean Sea during a cruise with RV <i>Poseidon</i> in April 2014

2015 ◽  
Vol 7 (2) ◽  
pp. 231-237 ◽  
Author(s):  
D. Hainbucher ◽  
V. Cardin ◽  
G. Siena ◽  
U. Hübner ◽  
M. Moritz ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Water Column ◽  
Eastern Mediterranean ◽  
Acoustic Doppler Current Profiler ◽  
Intermediate Water ◽  
German Research ◽  
Current Profiler ◽  
The Mediterranean ◽  
Vertical Spacing

Abstract. We report on data from an oceanographic cruise in the Mediterranean Sea on the German research vessel Poseidon in April 2014. Data were taken on a west–east section, starting at the Strait of Gibraltar and ending south-east of Crete, as well on sections in the Ionian and Adriatic Sea. The objectives of the cruise were threefold: to contribute to the investigation of the spatial evolution of the Levantine Intermediate Water (LIW) properties and of the deep water masses in the eastern Mediterranean Sea, and to investigate the mesoscale variability of the upper water column. The measurements include salinity, temperature, oxygen and currents and were conducted with a conductivity, temperature and depth(CTD)/rosette system, an underway CTD and an acoustic Doppler current profiler (ADCP). The sections are on tracks which have been sampled during several other cruises, thus supporting the opportunity to investigate the long-term temporal development of the different variables. The use of an underway CTD made it possible to conduct measurements of temperature and salinity with a high horizontal spacing of 6 nm between stations and a vertical spacing of 1 dbar for the upper 800 m of the water column.

scholarly journals New Mediterranean Biodiversity Records (October 2015)

2015 ◽  
Vol 16 (3) ◽  
pp. 682 ◽  
Author(s):  
F. CROCETTA ◽  
D. AGIUS ◽  
P. BALISTRERI ◽  
M. BARICHE ◽  
Y.K. BAYHAN ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Eastern Mediterranean ◽  
Tyrrhenian Sea ◽  
Ionian Sea ◽  
Oplegnathus Fasciatus ◽  
Pterois Miles ◽  
Entire Country ◽  
Alien Fish ◽  
The Mediterranean ◽  
Mediterranean Biodiversity

The Collective Article “New Mediterranean Biodiversity Records” of the Mediterranean Marine Science journal offers the means to publish biodiversity records in the Mediterranean Sea. The current article is divided per countries, listed according to a Mediterranean west-east geographic position. New biodiversity data are reported for 7 different countries, although one species hereby reported from Malta is overall new for the entire Mediterranean basin, and is presumably present also in Israel and Lebanon (see below in Malta). Italy: the rare native fish Gobius kolombatovici is first reported from the Ionian Sea, whilst the alien jellyfish Rhopilema nomadica and the alien fish Oplegnathus fasciatus are first reported from the entire country. The presence of O. fasciatus from Trieste is concomitantly the first for the entire Adriatic Sea. Finally, the alien bivalve Arcuatula senhousia is hereby first reported from Campania (Tyrrhenian Sea). Tunisia: a bloom of the alien crab Portunus segnis is first reported from the Gulf of Gabes, from where it was considered as casual. Malta: the alien flatworm Maritigrella fuscopunctata is first recorded from the Mediterranean Sea on the basis of 25 specimens. At the same time, web researches held possible unpublished records from Israel and Lebanon. The alien crab P. segnis, already mentioned above, is first formally reported from Malta based on specimens collected in 1972. Concomitantly, the presence of Callinectes sapidus in Maltese waters is excluded since based on misidentifications. Greece: the Atlantic northern brown shrimp Penaeus atzecus, previously known from the Ionian Sea from sporadic records only, is now well established in Greek and international Ionian waters. The alien sea urchin Diadema setosum is reported from the second time from Greece, and its first record date from the country is backdated to 2010 in Rhodes Island. The alien lionfish Pterois miles is first reported from Greece and concomitantly from the entire Aegean Sea. Turkey: the alien rhodophyte Antithamnion hubbsii is first recorded from Turkey and the entire eastern Mediterranean. New distributional data are also offered for the native fishes Alectis alexandrina and Heptranchias perlo. In particular, the former record is constituted by a juvenile of 21.38 mm total length, whilst the latter by a mature male. Cyprus: the rare native cephalopod Macrotritopus defilippi, and the alien crab Atergatis roseus, sea slug Plocamopherus ocellatus and fish Cheilodipterus novemstriatus are first recorded from the entire country. Lebanon: the alien crabs Actaea savignii and Matuta victor, as well as the alien fish Synanceia verrucosa, are first recorded from the entire country. In addition, the first Mediterranean record of A. savignii is backdated to 2006, whilst the high number of M. victor specimens observed in Lebanon first suggest its establishment in the basin. The Atlantic fishes Paranthias furcifer and Seriola fasciata, and the circumtropical Rachycentron canadum, are also first reported from the country. P. furcifer record backdate its presence in the Mediterranean to 2007, whilst S. fasciata records backdate its presence in the eastern Mediterranean to 2005. Finally, two of these latter species have been recently ascribed to alien species, but all the three species may better fit the cryptogenic category, if not a new one.

scholarly journals Modelling of the anthropogenic tritium transient and its decay product helium-3 in the Mediterranean Sea using a high-resolution regional model

Ocean Science ◽  
2015 ◽  
Vol 11 (3) ◽  
pp. 323-342 ◽  
Author(s):  
M. Ayache ◽  
J.-C. Dutay ◽  
P. Jean-Baptiste ◽  
K. Beranger ◽  
T. Arsouze ◽  
...  
Keyword(s):  
High Resolution ◽  
Mediterranean Sea ◽  
Deep Water ◽  
Numerical Study ◽  
Eastern Mediterranean ◽  
Decay Product ◽  
Regional Model ◽  
Eastern Basin ◽  
Helium 3 ◽  
The Mediterranean

Abstract. This numerical study provides the first simulation of the anthropogenic tritium invasion and its decay product helium-3 (3He) in the Mediterranean Sea. The simulation covers the entire tritium (3H) transient generated by the atmospheric nuclear weapons tests performed in the 1950s and early 1960s and is run till 2011. Tritium, helium-3 and their derived age estimates are particularly suitable for studying intermediate and deep-water ventilation and spreading of water masses at intermediate/deep levels. The simulation is made using a high-resolution regional model NEMO (Nucleus for European Modelling of the Ocean), in a regional configuration for the Mediterranean Sea called MED12, forced at the surface with prescribed tritium evolution derived from observations. The simulation is compared to measurements of tritium and helium-3 performed along large-scale transects in the Mediterranean Sea during the last few decades on cruises of R/V Meteor: M5/6, M31/1, M44/4, M51/2, M84/3, and R/V Poseidon: 234. The results show that the input function used for the tritium generates a realistic distribution of the main hydrographic features of the Mediterranean Sea circulation. In the eastern basin, the results highlight the weak formation of Adriatic Deep Water in the model, which explains its weak contribution to the Eastern Mediterranean Deep Water (EMDW) in the Ionian sub-basin. It produces a realistic representation of the Eastern Mediterranean Transient (EMT) signal, simulating a deep-water formation in the Aegean sub-basin at the beginning of 1993, with a realistic timing of deep-water renewal in the eastern basin.

scholarly journals Hydrography in the Mediterranean Sea during a cruise with RV <i>POSEIDON</i> in April 2014

2015 ◽  
Vol 8 (1) ◽  
pp. 427-446
Author(s):  
D. Hainbucher ◽  
V. Cardin ◽  
G. Siena ◽  
U. Hübner ◽  
M. Moritz ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Adriatic Sea ◽  
Eastern Mediterranean ◽  
Intermediate Water ◽  
Strait Of Gibraltar ◽  
Eastern Mediterranean Sea ◽  
German Research ◽  
The Mediterranean ◽  
Long Term Variations

Abstract. We report on data from an oceanographic cruise in the Mediterranean Sea on the German research vessel POSEIDON in April 2014. Data were taken on a west–east section starting at the Strait of Gibraltar and ending south-east of Crete as well on sections in the Ionian and Adriatic Sea. The objectives of the cruise were twofold; long-term variations of the Levantine Intermediate Water (LIW) and the deep water masses of the Eastern Mediterranean Sea were investigated. The measurements include salinity, temperature, oxygen and currents and were conducted with a CTD/rosette system, an underway CTD and an ADCP. The sections are on tracks which have been sampled during several other cruises, thus supporting the opportunity to investigate the long term temporal development of the different variables. The use of an underway CTD made it possible to conduct measurements of temperature and salinity with a high resolution of 6 nm and a vertical resolution of 1 dbar for the upper 800 m of the water column.

scholarly journals Recent findings of Ommastrephes bartramii (Cephalopoda: Ommastrephidae) in the eastern Mediterranean and the implication on its range expansion

2011 ◽  
Vol 12 (2) ◽  
pp. 413 ◽  
Author(s):  
E. LEFKADITOU ◽  
P. PERISTERAKI ◽  
N. CHARTOSIA ◽  
A. SALMAN
Keyword(s):  
Mediterranean Sea ◽  
Species Distribution ◽  
Eastern Mediterranean ◽  
Aegean Sea ◽  
Intermediate Water ◽  
Ommastrephes Bartramii ◽  
Western Basin ◽  
The North ◽  
Lower Beak ◽  
The Mediterranean

The neon flying squid Ommastrephes bartramii is found circumglobally in subtropical, temperate waters and sustains important fisheries in the North Pacific, but it is rarely encountered in the Mediterranean Sea. During the last decade, and particularly since 2004, the frequency of its presence in the Aegean Sea and nearby regions has increased, raising a question about a change in the species distribution and abundance in this area. In this study, we reviewed the literature on O. bartramii findings in the Mediterranean Sea and present new data describing body and beak morphometry, diet and the maturity of specimens recently collected from the easternmost basins. According to data from the entire Mediterranean Sea, collected individuals reached 66 cm in mantle length (ML), wherein only females were larger than 32 cm in ML. An isometric growth in body weight (BW) was shown, whereas the lower beak rostral length (LRL) was allometrically positive in relation to the ML. Occasional catches by jigs during experimental cruises provided most of the individuals recorded in the period from 1982-1992. In contrast, the most recent records are primarily comprised of mature females collected on or near the shore in the eastern basin and of predominantly smaller individuals from the western basin caught by professional jigging fisheries. The distribution of the specimen recorded from the Aegean Sea indicates an association between the species distribution and the circulation of the warm Levantine Intermediate Water. The more frequent observations of moribund spawning females at the periphery of the Cretan Sea are indicative of a spawning ground at this area. The suspected recent increase of O. bartramii abundance in both the northeastern and northwestern basins might be due to the warming of upper sea layers, which has been observed since the mid-1980s and is considered to be the main factor driving the northward expansion of the warm-water species’ range within the Mediterranean Sea.

scholarly journals Modelling of the anthropogenic tritium transient and its decay product helium-3 in the Mediterranean Sea using a high-resolution regional model

2014 ◽  
Vol 11 (6) ◽  
pp. 2691-2732
Author(s):  
M. Ayache ◽  
J.-C. Dutay ◽  
P. Jean-Baptiste ◽  
K. Beranger ◽  
T. Arsouze ◽  
...  
Keyword(s):  
High Resolution ◽  
Mediterranean Sea ◽  
Deep Water ◽  
Eastern Mediterranean ◽  
Decay Product ◽  
Regional Model ◽  
Western Basin ◽  
Eastern Basin ◽  
Helium 3 ◽  
The Mediterranean

Abstract. This numerical study provides the first simulation of the anthropogenic tritium invasion and its decay product helium-3 (3He) in the Mediterranean Sea. The simulation covers the entire tritium (3H) transient generated by the atmospheric nuclear-weapon tests performed in the 1950s and early 1960s and run till 2011. Tritium, helium-3 and their derived age estimates are particularly suitable for studying intermediate and deep-water ventilation and spreading of water masses at intermediate/deep levels. The simulation is made using a high resolution regional model NEMO-MED12 forced at the surface with prescribed tritium evolution derived from observations. The simulation is compared to measurements of tritium and helium-3 performed along large-scale transects in the Mediterranean Sea during the last few decades on cruises of Meteor M5/6, M31/1, M44/4, M51/2, M84/3, and Poseidon 234. The results show that the input function used for the tritium, generates a realistic distribution of the main hydrographic features of the Mediterranean Sea circulation. In the eastern basin, the results highlight the weak formation of Adriatic Deep Water in the model, which explains its weak contribution to the Eastern Mediterranean Deep Water in the Ionian sub-basin. It produces a realistic representation of the Eastern Mediterranean Transient signal, simulating a deep-water formation in the Aegean sub-basin at the beginning of the 1993, with a realistic timing of deep-water renewal in the eastern basin. In the western basin, the unusual intense deep convection event of winter 2005 in the Gulf of Lions during the Western Mediterranean Transition is simulated. However the spreading of the recently ventilated deep water toward the South is too weak. The ventilation and spreading of the Levantine Intermediate Water from the eastern basin toward the western basin is simulated with realistic tracer-age distribution compared to observation-based estimates.

scholarly journals The Conflict Between Greece And Turkey In The Mediterranean Sea (International Maritime Law Study)

Jurnal Hukum ◽  
2020 ◽  
Vol 36 (2) ◽  
pp. 126
Author(s):  
Edanur Yıldız
Keyword(s):  
International Law ◽  
Mediterranean Sea ◽  
Eastern Mediterranean ◽  
East Mediterranean ◽  
International Courts ◽  
Maritime Law ◽  
The Mediterranean

Turkey and Greece are again dragged into a new conflict in the East Mediterranean. Turkey and Greece vie for supremacy in the eastern Mediterranean. Turkey, for its part, indicated that Greece's claim to the territory would amount to a siege in the country by giving Greece a disproportionate amount of territory. This study aims to rethink the conflict between Greece and Turkey in the waters of the Mediterranean sea in the view of international maritime law. This study uses an empirical juridical approach. The Result of this research is Turkey does not ignore the Greece rights, Greece ignores the international law with its extended or excessive maritime claims. Greece tries to give full entitlement of the islands in Mediterranean and Agean. Whereas the effect Formula is applied by international courts.

scholarly journals Characterization of Coolia spp. (Gonyaucales, Dinophyceae) from Southern Tunisia: first record of Coolia malayensis in the Mediterranean Sea

ALGAE ◽  
2021 ◽  
Vol 36 (3) ◽  
pp. 175-193
Author(s):  
Moufida Abdennadher ◽  
Amel Bellaaj Zouari ◽  
Walid Medhioub ◽  
Antonella Penna ◽  
Asma Hamza
Keyword(s):  
Electron Microscopy ◽  
Mediterranean Sea ◽  
Phylogenetic Trees ◽  
Eastern Mediterranean ◽  
First Record ◽  
Morphological Characterization ◽  
Mucus Production ◽  
Rdna Sequences ◽  
The Mediterranean ◽  
Morphological Differences

This study provides the first report of the presence of Coolia malayensis in the Mediterranean Sea, co-occurring with C. monotis. Isolated strains from the Gulf of Gabès, Tunisia (South-eastern Mediterranean) were identified by morphological characterization and phylogenetic analysis. Examination by light and scanning electron microscopy revealed no significant morphological differences between the Tunisian isolates and other geographically distant strains of C. monotis and C. malayensis. Phylogenetic trees based on ITS1-5.8S-ITS2 and D1‒D3/28S rDNA sequences showed that C. monotis strains clustered with others from the Mediterranean and Atlantic whereas the C. malayensis isolate branched with isolates from the Pacific and the Atlantic, therefore revealing no geographical trend among C. monotis and C. malayensis populations. Ultrastructural analyses by transmission electron microscopy revealed the presence of numerous vesicles containing spirally coiled fibers in both C. malayensis and C. monotis cells, which we speculate to be involved in mucus production.

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