Pedro Freitas

Physical, chemical and sedimentological aspects of the Mediterranean outflow off Iberia

A multidisciplinary study of the Mediterranean outflow in the region west of the Strait of Gibraltar and off the southern and southwestern coasts of the Iberian Peninsula was developed in the frame of the Canary Islands Azores Gibraltar Observations Project. Two high-resolution CTD surveys, which included water sampling for chemical (nutrients and dissolved oxygen) and sedimentological analyses, took place in September 1997 (summer cruise) and January 1998 (winter cruise) in the study region. The correspondence between the high-salinity Mediterranean Water (MW) layer and the low-nutrient content and relatively high abundance of particles was a general result. Further details of the thermohaline analysis and of the geostrophic computations, especially for the layer of MW, are compared with the results obtained for the chemical properties and the sedimentological characteristics.

Suspended particulate matter in the Mediterranean water at the Gulf of Cadiz and off the southwest coast of the Iberian Peninsula

Abstract Suspended particulate matter (SPM) data from two surveys carried as part of the Canary Islands Azores Gibraltar Observations (CANIGO) project, in September 1997 and January 1998, are presented for the Gulf of Cadiz and the SW coast of Portugal. Analysis of total suspended mass, particulate organic to inorganic matter ratio, δ13C(PDB), and a microscopic analysis of particle composition were performed. Our objective was to quantify and characterise SPM in the water masses present in the study area, North Atlantic central water (NACW), North Atlantic deep water (NADW), and especially in the Mediterranean water (MW). MW was usually characterised by values of SPM higher than NADW but similar to NACW, and was different in terms of SPM composition: higher δ13C(PDB) values and relative abundance of mineral and biogenic particles, but lower relative abundance of particles