Prasonisi, the Southwest point thereof, on to Vrontos Point (35°33′N) in Skarpanto [Karpathos], through this island to Castello Point, the South extreme thereof, across to Cape Plaka (East extremity of Crete), through Crete to Agria Grabusa, the Northwest extreme thereof, thence to Cape Apolitares in Antikithera Island, through the island to Psira Rock (off the Northwest point) and across to Cape Trakhili in Kithera Island, through Kithera to the Northwest point (Cape Karavugia) and thence to Cape Santa Maria () in the Morea. In the Dardanelles: A line joining Kum Kale (26°11′E) and Cape Helles. Hydrography Aegean surface water circulates in a counterclockwise gyre, with hypersaline Mediterranean water moving northward along the west coast of Turkey, before being displaced by less dense Black Sea outflow. The dense Mediterranean water sinks below the Black Sea inflow to a depth of , then flows through the Dardanelles Strait and into the Sea of Marmara at velocities of . The Black Sea outflow moves westward along the northern Aegean Sea, then flows southwards along the east coast of Greece. The physical oceanography of the Aegean Sea is controlled mainly by the regional climate, the fresh water discharge from major rivers draining southeastern Europe, and the seasonal variations in the Black Sea surface water outflow through the Dardanelles Strait. Analysis of the Aegean during 1991 and 1992 revealed three distinct water masses: Aegean Sea Surface Water – thick veneer, with summer temperatures of 21–26 °C and winter temperatures ranging from in the north to in the south. Aegean Sea Intermediate Water – Aegean Sea Intermediate Water extends from 40 to 50 m to with temperatures ranging from 11 to 18 °C. Aegean Sea Bottom Water – occurring at depths below 500–1000 m with a very uniform temperature (13–14 °C) and salinity (3.91–3.92%). Climate The climate of the Aegean Sea largely reflects the climate of Greece and Western Turkey, which is to say, predominately Mediterranean. According to the Köppen climate classification, most of the Aegean is classified as Hot-summer Mediterranean (Csa), with hotter and drier summers along with milder and wetter winters. However, high temperatures during summers are generally not quite as high as those in arid or semiarid climates due to the presence of a large body of water. This is most predominant in the west and east coasts of the Aegean, and within the Aegean islands. In the north of the Aegean Sea,