Levantine Intermediate Water (LIW) The saltiest water mass that forms in the eastern Mediterranan Sea. It is exclusively formed in several areas of the Levantine Basin and the southern Aegean Sea in February and March under the influence of dry and cold continental air masses. Mesocale processes play an important role in the formation and spreading of LIW. After its formation, it forms a layer identified by a salinity maximum between the overlying Modified Atlantic Water (MAW) and the underlying Eastern Mediterranean Deep Water (EMDW). The core depth fluctuates from 50 to 600 m. The LIW flows eastwards and westwards, with part of the portion formed in the Levantine Basin entering the Aegean through the eastern straits of the Cretan Arc with core temperature and salinity values at the sill depths of 14.5°C and 38.9. Some of this water is ventilated and transformed by convective processes to become a slightly denser intermediate water mass called Cretan Intermediate Water (CIW). While the characteristics of the source waters generated at different regions vary (14.70-16.95°C, 38.85-39.15), mixing results in homogeneity and the loss of heat and salt as the LIW spreads westward. The slow spreading and long renewal time give LIW as relatively low oxygen content of less than 4.5 ml/l. The winter properties of LIW as it leaves the Levantine Sea are 15 =< q =< 16°C, 39.0 =< S =< 39.2, and 28.9 =< sq =< 29.0. In the Ionian Sea the properties are transformed into 14 =< q =< 15 C, S>= 38.8, and 29.0 =< sq =< 29.1. See Perkins and Pistek (1990), Ö (1993), Stratford and Williams (1997), Stergiou et al. (1997) and Theocharis et al. (1999).
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