Temporal variability of sea-level in Safaga Harbour, Egypt in relation with meteorological conditions and tidal characteristics

The present work affords a comprehensive tidal analysis with diverse terms and beneficial information, which can be utilised for navigational and engineering purposes, and contributes to the understanding of the sea level behaviour in Safaga Harbour. The study was built up on hourly data of sea level over 2 years from January 2012 to December 2013, with no missing data. The T_TIDE package was used to obtain the different astronomical amplitudes and phases over the study period. To correlate with the affecting meteorological conditions, simultaneous hourly meteorological records were considered. These comprised air temperature, atmospheric pressure, and wind speed. Results revealed that tides in Safaga Harbour are of semidiurnal type. The impact of the astronomical tides on the observed sea level was 1.5 times that of meteorological factors, with a spring to neap ratio of 1.3. The mean sea level (MSL) was 0.56 m, exhibiting seasonal variation with the lowest value of 0.45 m in winter (December) and the highest of 0.71 m in summer (August). According to the present findings, the calculated mean tidal level (MTL) of 0.61 m was higher by 0.05 m than the MSL, which declares the importance of the shallow-water components upon studying the sea level variations in the sheltered coastal region of Safaga Harbour as they are increasingly spatially variable. Furthermore, the detected sea level variations in the Harbour were tightly correlated with the air temperature and atmospheric pressure than with the wind speed either zonal or meridional.