The geostrophic current velocity at the edge of the Mersa

Matruh gyre varied between 12.5 and 29.1 cm sec−1 in winter and between 6.5 and 13.1 cm sec−1 in summer (Said & Eid 1994b). In order to study the vertical distribution of the hydrographic parameters, the average winter values of each of the water temperature, salinity and density σt were presented on a vertical section taken parallel to the Egyptian Coast along latitude 32°30′N and between longitudes 25°30′ and 34°E ( Figure 7). The vertical distribution of the water temperature in the upper 200 m layer of this section shows great uniformity in temperature in the western part of the study area, which could be attributed to severe cooling at the sea surface in winter. In the eastern part of the area, the water temperature decreases from 18.5°C at the Talazoparib surface to 15.5°C at 250 m depth, indicating a gradient of 0.012°C m−1. Salinity values increase eastwards and also show great homogeneity, obviously due to vertical mixing

(Figure 7b). Only one surface water mass could be observed during winter in the upper RO4929097 order 200 m layer. It is characterized by temperatures from 15° to 17°C, a salinity maximum in the range of 38.90–> 39.10 PSU and corresponding density values of 28.5–28.9 σt ( Figure 7). This water mass was previously observed and discussed in detail by Said et al. (2007). In summer, the surface water temperature varied between 22 and 28°C, except in an area with slightly colder water (Figure 8). This Dapagliflozin is the area of the above-mentioned Mersa Matruh gyre, which lies between longitudes 27° and 29°E. The gyre area is characterized by low water temperatures (22–25°C), salinities of 39.10–39.20 PSU and a high density (26.4–27 σt). Figure 9 illustrates the vertical distributions of the temperature, salinity and potential density σt for a transect along latitude 32°30′N between longitudes 25°30′ and 34°E. The temperature distribution clearly

shows that due to the warming effect of the sun in summer, the surface water temperature increases to 28.0°C, and a strong thermocline is clearly developed. Within the 20–100 m layer, the temperature decreases, on average, by about 6°C from 24 to 18°C, giving rise to a large vertical temperature gradient. High salinity values of 38.90–39.20 PSU are found in the upper 50 m layer. The salinity generally decreases with increasing depth to reach 38.80 PSU at 150 m depth but then increases downwards. A layer of salinity values from < 38.60 to 38.80 PSU is observed at 50–150 m depth throughout the area from west to east. It spreads over the range of density between 27.5 and 28.5 σt. Three water masses could be observed in the upper 250 m layer in summer. The surface water mass occupies the upper layer from 30 to 50 m depth, and has temperatures from 22° to 28°C and salinities from 38.8 to 39.20 PSU.