Extreme environments and transitional aquatic systems.

Supplemento 1 del volume 20 di Chemistry and Ecolog

La sedimentation holocene du golfe de Tarente (Italie meridionale): approche stratigraphique et paléoclimatique basée sur l'étude de trois carottes de sondage.

peer reviewe

Terra Nova Bay: hot spot in marine and terrestrial biodiversity, knowledge and functioning of the ecosystem

The Terra Nova Bay area is particularly valuable for science due to the presence of unique marine and terrestrial flora and fauna and the high diversity at both species and community level. From an oceanographic perspective, the area is characterised by the occurrence of the Terra Nova Bay polynya, a crucial region for the formation of the High Salinity Shelf Water (HSSW), formed by the salination of the Circumpolar Deep Water (CDW), that penetrates onto the continental shelf of the Ross Sea. Herein, high primary production and strong benthic-pelagic coupling support species- and biomass-rich communities, either on the sea bottom (e.g. scallops and sponges) and in the water column. In fact, Terra Nova Bay represents a nursery area for the pelagic silverfish, a key species in the coastal food web, and hosts large assemblages of the crystal krill. All this supports several colonies of top-predators, such as Adélie and emperor penguins, as well as flying sea-birds and marine mammals. The Terra Nova Bay area has been widely investigated in the last 25 years: extensive geological, oceanographic, marine and terrestrial ecological and biological research has been carried out, contributing substantially to our understanding of ecosystem functioning and community processes. The existence of several biodiversity databases (both terrestrial and marine) and of an ongoing marine long term research monitoring program make this area of high ecological and scientific value. All these peculiarities have been already acknowledged through the establishment of two ASPAs (N° 161 and 165) and the setting up of a marine LTER site. The awareness that the processes that make this area particularly valuable occur at a spatial scale which is larger than the presently protected areas suggests that management and conservation measures should be applied at a larger scale, by embracing more sites or enlarging the existing ones

General circulation of the Eastern Mediterranean

A novel description of the phenomenology of the Eastern Mediterranean is presented based upon a comprehensive pooled hydrographic data base collected during 1985-1987 and analyzed by cooperating scientists from several institutions and nations (the POEM project). Related dynamical process and modeling studies are also overviewed. The circulation and its variabilities consist of three predominant and interacting scales: basin scale, subbasin scale, and mesoscale. Highly resolved and unbiased maps of the basin wide circulation in the thermocline layer are presented which provide a new depiction of the main thermocline general circulation, composed of subbasin scale gyres interconnected by intense jets and meandering currents. Semipermanent features exist but important subbasin scale variabilities also occur on many time scales. Mesoscale variabilities modulate the subbasin scale and small mesoscale eddies populate the open sea, especially the south-eastern Levantine basin. Clear evidence indicates Levantine Intermediate Water (LIW) to be present over most of the Levantine Basin, implying that formation of LIW is not localized but rather is ubiquitous. The Ionian and Levantine basins are confirmed to form one deep thermohaline cell with deep water of Adriatic origin and to have a turnover time of one and a quarter centuries. Prognostic, inverse, box and data assimilative modeling results are presented based on both climatological and POEM data. The subbasin scale elements of the general circulation are stable and robust to the dynamical adjustment process. These findings bear importantly on a broad range of problems in ocean science and marine technology that depend upon knowledge of the general circulation and water mass structure, including biogeochemical fluxes, regional climate, coastal interactions, pollution and environmental management. Of global ocean scientific significance are the fundamental processes of water mass formations, transformations and dispersion which occur in the basin. © 1992

General Circulation of the Eastern Mediterranean

A novel description of the phenomenology of the Eastern Mediterranean is presented based upon a comprehensive pooled hydrographic data base collected during 1985–1987 and analyzed by cooperating scientists from several institutions and nations (the POEM project). Related dynamical process and modeling studies are also overviewed. The circulation and its variabilities consist of three predominant and interacting scales: basin scale, subbasin scale, and mesoscale. Highly resolved and unbiased maps of the basin wide circulation in the thermocline layer are presented which provide a new depiction of the main thermocline general circulation, composed of subbasin scale gyres interconnected by intense jets and meandering currents. Semipermanent features exist but important subbasin scale variabilities also occur on many time scales. Mesoscale variabilities modulate the subbasin scale and small mesoscale eddies populate the open sea, especially the south-eastern Levantine basin. Clear evidence indicates Levantine Intermediate Water (LIW) to be present over most of the Levantine Basin, implying that formation of LIW is not localized but rather is ubiquitous. The Ionian and Levantine basins are confirmed to form one deep thermohaline cell with deep water of Adriatic origin and to have a turnover time of one and a quarter centuries. Prognostic, inverse, box and data assimilative modeling results are presented based on both climatological and POEM data. The subbasin scale elements of the general circulation are stable and robust to the dynamical adjustment process. These findings bear importantly on a broad range of problems in ocean science and marine technology that depend upon knowledge of the general circulation and water mass structure, including biogeochemical fluxes, regional climate, coastal interactions, pollution and environmental management. Of global ocean scientific significance are the fundamental processes of water mass formations, transformations and dispersion which occur in the basin.Earth and Planetary Science