Here,

α is the thermal expansion coefficient, taken to be 3.2 × 10− 4 °C− 1 and cp = 3.98 J g− 1 °C− 1 (salinity ≈ 39.5‰ and temperature 28.5°C); Various studies relating to water column conditions have been carried out in different areas. Holloway (1980) considers thermal stratification in a water body subjected to atmospheric heating and wind-induced vertical mixing. Simpson et al. (1990) discuss how buoyancy input as fresh water exerts a stratifying influence in estuaries and adjacent coastal waters. Liu (2007) found that, in the Bohai Sea, stratification comes into existence in April, peaks in July and decays towards October. Buranapratheprat et al. (2008) discuss the water column conditions

in the upper check details Gulf of Thailand based on surface heat flux, river discharge, tidal and wind mixing. They show that stratification develops in May because of surface heating and is dominant in October due to the large river discharge. Monthly variations VX-809 clinical trial of the surface heat fluxes are taken from Ahmad et al. (1989) and the results are reproduced in Figure 2 along with the net surface heat flux. Wind speed data (1990–2000) for Jeddah airport are provided by PME (Presidency of Meteorology and Environment) of Saudi Arabia. The monthly averages of wind speed are plotted in Figure 3a. The hydrographic data and the tidal current speeds are from Ahmad et al. (1997). The measured tidal current velocities are also plotted in Figure 3b and the temperature and salinity for the months of April and September 1997 for three stations are shown in Figure 4. The tidal current velocity in the main body of the Phosphatidylinositol diacylglycerol-lyase lagoon

varied from about 0.05 m s− 1 to about 0.2 m s− 1 depending on the spring-neap cycle and the seasonal variations of the mean sea level in the Red Sea. The tidal currents at the inlet were faster owing to the narrowness of the entrance. When the net heat at the air-sea interface Q   < 0, from November to March ( Figure 2), then the potential energy due to the surface heat flux will not contribute to stratification and the water column is mixed. When the heat balance Q   > 0, surface heating will contribute to stratification and tidal and wind mixing will be opposed, so stratification will depend on their net contribution. The calculations are therefore made for April to October only. The net surface heat flux at the air-sea interface from April to October, as well as the tidal current velocities and the wind speeds for this period are listed in Table 1. Based on this data dvdt is computed for surface heat flux, tidal and wind mixing terms. The values are given in Table 2 along with the net changes in potential energy. From the hydrographic data at three stations in the Rabigh Lagoon (Ahmad et al.