Large-scale properties of the eastern mediterranean - A review

Abstract

RESUME Paola MALANOTTE-RIZZOLI a, Artur HECHT b a Department of Earth, Atmospheric, and Planetary Sciences, 54-1420, Center for Meteorology and Physical· Oceanography, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. b Israel Oceanographie and Limnological Research, National Institute of Oceanography, Tel-Shikmona, POB 8030, Haifa, 31080 Israel. * also Senior Scientist of the Istituto Studio Dimamica Grandi Masse, CNR, Venice, Ital y (on leave). Received 3/6/87, in revised forrn 8/2/88, accepted 15/2/88. A review is provided of the present state of knowledge of the Eastern Mediterranean, including both its phenomenology (general circulation, water masses, specifie local processes) and the theoretical efforts devoted to modelling these properties. The general conclusion is that very little is known of the Eastern Mediterranean in comparison with other interesting regions of the world's ocean. The phenomenological evidence is still inconclusive and contradictory, and Ieaves unsolved the major questions concerning the basic physical mechanisms and driving forces of the circulation itself (wind versus thermohaline driven). The role of tracer distributions in determining circulation patterns is still poorly understood. Modelling efforts are scanty and often provide contradictory results. We address the major and critical questions which must be answered to obtain a basic understanding of the dynamics of the Eastern Mediterranean; we review the present knowledge of its phenomenology and of the modelling research carried out up to now, critically assessing what is still poorly known or ambiguous. Oceanol. Acta, 1988, 11, 4, 323-335. La circulation generale de la Mediterranee orientale : synthese de sa phenomenologie et modelisation ) ' 1 Nous presentons une synthese de l'etat actuel des connaissances relatives a la phenomenologie de la Mediterranee orientale (circulation generale, masses d'eau, phenomenes locaux specifiques) et des efforts theoriques poursuivis pour modeliser ces proprietes. La conclusion generale est que la Mediterranee orientale est tres mal connue, comparee aux autres regions interessantes de l'ocean mondial. La connaissance phenomenologique est encore contradictoire et peu concluante; les principales questions ne sont toujours pas resolues dans le domaine des mecanismes physiques fondamentaux et des forces qui determinent la circulation elle-meme (due au vent, thermohaline). Le role de la repartition des traceurs dans la determination des modeles de circulation est encore mal compris. Les essais de modelisation sont rares, et conduisent souvent a des resultats contradictoires. Nous posons les questions fondamentales necessaires a la comprehension de la dynamique de la Mediterranee orientale; nous faisons la synthese des connaissances actuelles de sa phenomenologie et de la recherche effectuee jusqu'a present pour la modeliser, et nous inventorions ce qui reste mal connu. Oceanol. Acta, 1988, 11, 4, 323-335. 0399-1784/88/04 323 13/S 3.30/11:1 Gauthier-Villars 323 P. MALANOTTE-RIZZOLI. A. HECHT