Evolution of dynamics in the eastern Mediterranean affecting water mass structures and properties in the Ionian and Adriatic Seas

2003 ◽  
Vol 108 (C9) ◽  
Author(s):  
Beniamino B. Manca
Keyword(s):  
Water Mass ◽  
Eastern Mediterranean ◽  
Structures And Properties ◽  
Ionian And Adriatic Seas

scholarly journals Thermohaline properties in the Eastern Mediterranean in the last three decades: is the basin returning to the pre-EMT situation?

2014 ◽  
Vol 11 (1) ◽  
pp. 391-423 ◽  
Author(s):  
V. Cardin ◽  
G. Civitarese ◽  
D. Hainbucher ◽  
M. Bensi ◽  
A. Rubino
Keyword(s):  
Deep Water ◽  
Water Mass ◽  
Deep Layer ◽  
Eastern Mediterranean ◽  
Salt Content ◽  
Intermediate Water ◽  
Levantine Basin ◽  
Mass Properties ◽  
Wide Scale ◽  
East West

Abstract. We present temperature, salinity and oxygen data collected during the M84/3 and P414 cruises in April and June 2011 on a basin-wide scale to determine the ongoing oceanographic characteristics in the Eastern Mediterranean (EM). The east–west transect through the EM sampled during the M84/3 cruise together with data gained on previous cruises over the period 1987–2011 are analysed in terms of regional aspects of the evolution of water mass properties and heat and salt content variation. The present state of the EM basin is also evaluated in the context of the evolution of the Eastern Mediterranean Transient (EMT). From this analysis we can infer that the state of the basin is still far from achieving the pre-EMT conditions. Indeed, the 2011 oceanographic conditions of the deep layer of the central Ionian lie between the thermohaline characteristics of the EMT and the pre-EMT phase, indicating a possible slow return towards the latter. In addition, the thermohaline properties of the Adriatic Deep Water are still in line (warmer and saltier) as when it restarted to produce dense waters after the EMT. Special attention is given to the variability of thermohaline properties of the Levantine Intermediate Water and Adriatic Deep Water in three main areas: the Cretan, the central Levantine and the central Ionian Seas. Finally, this study evidences the relationships among the hydrological property distributions of the upper-layer in the Levantine basin and the circulation regime in the Ionian.

scholarly journals Biological condition and trophic ecology of the deep-water shrimp Aristaeomorpha foliacea in the Levantine Sea (SW Turkey)

2014 ◽  
Vol 16 (1) ◽  
pp. 103 ◽  
Author(s):  
K. Y. BAYHAN ◽  
J. E. CARTES ◽  
E. FANELLI
Keyword(s):  
Deep Water ◽  
Trophic Ecology ◽  
Water Mass ◽  
Isotope Composition ◽  
Eastern Mediterranean ◽  
Reproductive Period ◽  
Reproductive Capacity ◽  
Levantine Sea ◽  
Deep Water Species ◽  
Aristaeomorpha Foliacea

The trophic ecology (diets, stable isotope composition) and life cycle (gonado-somatic, GSI, and hepato-somatic, HSI, indices) of Aristaeomorpha foliacea were analysed seasonally (in May, June, and November 2012 and January 2013) off southeast Turkey (Levantine Basin), over the slope at 442-600 m depth. A. foliacea females were mature in June, suggesting gonad maturity was somewhat delayed off southeast Turkey compared to other areas in the Eastern Mediterranean. The HSI of A. foliacea was highest in May and June (8.2% of body weight) for males and both immature and mature females, sharply lower in November (3.5%) and then increasing again in winter (7.1%). Stomach fullness (F) showed a tendency similar to HSI in both females and males, increasing from May to June. A. foliacea had rather low d15N (6.68‰ to 8.26‰) off southeast Turkey, with females having higher d15N with increasing size. The δ13C signal (-14.85 to -14.68‰) indicated that diet was mainly though not exclusively based on zooplankton (pelagic shrimps and small myctophids of 1.3-4.5 mm TL, cnidarians, hyperiids and pteropods). The increase of A. foliacea remains in A. foliacea guts and of some benthic prey (polychaetes, bivalves, gastropods) after the reproductive period would explain the moderate depletion of δ13C in spring-summer. The greatest changes in the diet occurred between periods of water mass stratification (June and November) and periods of water mass homogeneity (May and January), with greater consumption of zooplankton in the latter season. A. foliacea seems to have lower reproductive capacity (GSI 5.6%) than other deep-water species of penaeidae that live shallower (Parapenaues longirostris) and deeper (Aristeus antennatus) than it does. The species has a more specialized zooplankton diet, exploiting short, more efficient trophic chains, which could be an advantage explaining its dominance in oligotrophic areas of the Central-Eastern Mediterranean, including the Turkish slope.

scholarly journals Hydrographic situation during cruise M84/3 and P414 (spring 2011) in the Mediterranean Sea

2013 ◽  
Vol 10 (6) ◽  
pp. 2399-2432 ◽  
Author(s):  
D. Hainbucher ◽  
A. Rubino ◽  
V. Cardin ◽  
T. Tanhua ◽  
K. Schroeder ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Large Scale ◽  
Water Mass ◽  
Eastern Mediterranean ◽  
Physical Parameters ◽  
Strait Of Gibraltar ◽  
Mass Properties ◽  
The Mediterranean ◽  
Geostrophic Velocities ◽  
Lebanese Coast

Abstract. Hydrography and large scale circulation observed in the Mediterranean Sea during the M84/3 and P414 cruises (April and June 2011, respectively) are presented. In contrast to most of the recent expeditions, which were limited to special areas of the basin, these two cruises, especially the M84/3, offered the opportunity of delineating a quasi-synoptic picture of the distribution of the relevant physical parameters through the whole Mediterranean. A section was observed from the Lebanese coast up to the Strait of Gibraltar. The focus of our analysis are the water mass properties, also in the context of the recently observed variability, and a comparison between the velocity fields observed using a vessel-mounted ADCP and those calculated from the observed density fields. Overall, a distribution of temperature, salinity, and geostrophic velocities emerges, which seems far from that observed before the beginning of the so-called "Eastern Mediterranean Transient", a major climatic shift in the hydrography and circulation of the Mediterranean Sea occurred at the end of 1980s. Here, our focus is a discussion of the observed water mass properties analysed through T–S diagrams and through an Optimum Multiparameter (OMP) analysis. Additionally, ADCP velocities are compared to geostrophic calculations.

scholarly journals Aegean Sea Water Masses during the Early Stages of the Eastern Mediterranean Climatic Transient (1988–90)

2006 ◽  
Vol 36 (9) ◽  
pp. 1841-1859 ◽  
Author(s):  
I. Gertman ◽  
N. Pinardi ◽  
Y. Popov ◽  
A. Hecht
Keyword(s):  
Surface Water ◽  
Deep Water ◽  
Water Mass ◽  
Sea Water ◽  
Eastern Mediterranean ◽  
Aegean Sea ◽  
Water Masses ◽  
Intermediate Water ◽  
Central Basin ◽  
Cretan Sea

Abstract The Aegean water masses and circulation structure are studied via two large-scale surveys performed during the late winters of 1988 and 1990 by the R/V Yakov Gakkel of the former Soviet Union. The analysis of these data sheds light on the mechanisms of water mass formation in the Aegean Sea that triggered the outflow of Cretan Deep Water (CDW) from the Cretan Sea into the abyssal basins of the eastern Mediterranean Sea (the so-called Eastern Mediterranean Transient). It is found that the central Aegean Basin is the site of the formation of Aegean Intermediate Water, which slides southward and, depending on their density, renews either the intermediate or the deep water of the Cretan Sea. During the winter of 1988, the Cretan Sea waters were renewed mainly at intermediate levels, while during the winter of 1990 it was mainly the volume of CDW that increased. This Aegean water mass redistribution and formation process in 1990 differed from that in 1988 in two major aspects: (i) during the winter of 1990 the position of the front between the Black Sea Water and the Levantine Surface Water was displaced farther north than during the winter of 1988 and (ii) heavier waters were formed in 1990 as a result of enhanced lateral advection of salty Levantine Surface Water that enriched the intermediate waters with salt. In 1990 the 29.2 isopycnal rose to the surface of the central basin and a large volume of CDW filled the Cretan Basin. It is found that, already in 1988, the 29.2 isopycnal surface, which we assume is the lowest density of the CDW, was shallower than the Kassos Strait sill and thus CDW egressed into the Eastern Mediterranean.

Modelling the water mass circulation in the Aegean Sea. Part I: wind stresses, thermal and haline fluxes

1994 ◽  
Vol 12 (8) ◽  
pp. 794-807 ◽  
Author(s):  
I. A. Valioulis ◽  
Y. N. Krestenitis
Keyword(s):  
Experimental Evidence ◽  
Black Sea ◽  
Computer Model ◽  
Seasonal Variations ◽  
Water Mass ◽  
Eastern Mediterranean ◽  
Aegean Sea ◽  
Water Fluxes ◽  
Physical Processes ◽  
Mass Circulation

Abstract. The aim of this work is to develop a computer model capable of simulating the water mass circulation in the Aegean Sea. There is historical, phenomenological and recent experimental evidence of important hydrographical features whose causes have been variably identified as the highly complex bathymetry, the extreme seasonal variations in temperature, the considerable fresh water fluxes, and the large gradients in salinity or temperature across neighbouring water masses (Black Sea and Eastern Mediterranean). In the approach taken here, physical processes are introduced into the model one by one. This method reveals the parameters responsible for permanent and seasonal features of the Aegean Sea circulation. In the first part of the work reported herein, wind-induced circulation appears to be seasonally invariant. This yearly pattern is overcome by the inclusion of baroclinicity in the model in the form of surface thermohaline fluxes. The model shows an intricate pattern of sub-basin gyres and locally strong currents, permanent or seasonal, in accord with the experimental evidence.

Sign in / Sign up

Export Citation Format

Share Document