Water fluxes through the Cretan Arc Straits, Eastern Mediterranean Sea: March 1994 to June 1995

Five research cruises were undertaken incorporating ADCP sections along the Cretan Are Straits and CTD surveys covering the entire area of the Straits and the Cretan Sea. In addition, six moorings (with 15 current meters) wer e deployed within the Straits, which monitored flows in the surface (50 m), intermediate (250 m), and deep (50 m from the bottom) layers. The ADCP, CM , and CTD datasets enable the derivation of water transports through the Cr etan Are Straits to be assessed. Flow structure through the Cretan Are Stra its is not the typical flow regime with a surface inflow and deep outflow, instead there is a persistent deep outflow of Cretan Deep Water (CDW) (sigm a(theta)>29.2) with an annual mean of similar to 0.6 Sv, through the Antiki thira and Kassos Straits at depths below 400 m and 500 m, respectively. CDW outflowing transports are higher (similar to 0.8 Sv) in April-June, and lo wer (similar to 0.3 Sv) in October-December. Within the upper water layer ( 0-similar to 400 m), the transport and the water exchanges through the Stra its are controlled by local circulation features, which weaken substantiall y below 200 m. The Asia Minor Current (AMC) influences the Rhodes and the K arpathos Straits, resulting in a net inflow of water. In contrast, the Mirt oan/West Cretan Cyclone influences the Antikithira and Kithira Straits, whe re there is a net outflow. In the Kassos Strait, there is a complex interac tion between the East Cretan Cyclone, the Ierapetra Anticyclone and the wes tward extension of the Rhodes Gyre, which results in a variable flow regime . There is a net inflow in autumn and early winter, and a switch to a net o utflow in early spring and summer. The total inflow and outflow, throughout all of the Straits, ranged from similar to 2 to similar to 3.5 Sv, with hi gher Values in autumn and early winter and lower in summer. The AMC carries similar to 2 Sv of inflow through the Rhodes and Karpathos Straits, and th is accounts for 60-80% of the total inflow. About 10-15% of the total outfl ow is of CDW, and a further 35-704 occurs through the upper 400 m of the Ki thira and Antikithira Straits. The Kassos Strait exhibits a net inflow of s imilar to 0.7 Sv in autumn and early winter, with a net outflow of similar to 0.5 Sv in early spring and summer. (C) 2000 Elsevier Science Ltd. All ri ghts reserved.