A study of the Alboran sea mesoscale system by means of empirical orthogonal function decomposition of satellite data

This paper presents the results of a combined empirical orthogonal function (EOF) analysis of Advanced Very High Resolution Radiometer (AVHRR) sea sur face temperature (SST) data and sea-viewing wide field-of-view sensor (SeaW iFS) chlorophyll concentration data over the Alboran Sea (Western Mediterra nean), covering a period of 1 year (November 1997-October 1998). The aim of this study is to go beyond the limited temporal extent of available in sit u measurements by inferring the temporal and spatial variability of the Alb oran Gyre system from long temporal series of satellite observations, in or der to gain insight on the interactions between the circulation and the bio logical activity in the system. In this context, EOF decomposition permits concise and synoptic representation of the effects of physical and biologic al phenomena traced by SST and chlorophyll concentration. Thus, it is possi ble to focus the analysis on the most significant phenomena and to understa nd better the complex interactions between physics and biology at the mesos cale. The results of the EOF analysis of AVHRR-SST and SeaWiFS-chlorophyll concentration data are presented and discussed in derail. These improve and complement the knowledge acquired during the in situ observational campaig ns of the MAST-III Observations and Modelling of Eddy scale Geostrophic and Ageostrophic motion (OMEGA) project. (C) 2001 Elsevier Science B.V. All ri ghts reserved.