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Alexandria Eastern Harbor (AEH) is constantly enduring the destructive problem of storm surges. Therefore, the investigation of the behavior of surges in the Harbor is crucial, and determining to which extent this is affected by the meteorological conditions is essential. We used hourly data of sea-level, from 10.06.2018 to 15.06.2020, to calculate AEH surge heights. Simultaneous records of winds and sea-level pressure (SLP) were used to examine their impact on the calculated surges. Also, an empirical equation was derived to estimate the surge height in AEH by knowing the SLP and winds. Results revealed a 99% contribution of surges to the recorded sea-level. Surge heights exhibited a seasonal pattern with lower values in spring and higher ones in summer. While the positive surges dominated the Harbor all the year-round, the negative surges appeared only in 8 months: January-June, in addition to October and November. The total and the positive surges were directly proportional to all wind components but the negative parallel ones. Contrariwise, the negative surge associated the decrease of all wind components except the negative parallel and the negative normal components. There was an inverse relationship between the total, positive and negative surge heights and the SLP.

The present study focuses on a comprehensive sea-level analysis in Alexandria Eastern Harbour (AEH). The study is based on hourly sea-level records from 10.06.2018 to 15.06.2020, from the new Inexpensive Device for Sea-level Measurement (IDSL), installed in AEH in June 2018. Before analysis, sea-level records were referred to the Mean Lower Low Water (MLLW) in the Harbour of −429 cm. The T_TIDE package was used to generate the astronomical tides. Residuals were calculated by subtracting the astronomical elevations from the observed sea-levels. Results revealed a mean sea-level of 24.6 cm. The seasonal behaviour of sea-level was determined with the lowest monthly means in spring and the highest in summer and winter. Tides in the Harbour are of semidiurnal type; with a mean tidal level of 0.05 cm. 23 tidal constituents out of 36 are significant, with SSa and M2 constituents having the largest amplitudes of 5.4 cm and 5.1 cm, respectively. Results revealed a ratio of 4.7 between spring and neap ranges. Residuals contribute to 99.0% in the recorded sea-level. The design risk factor and return periods of positive sea-level ranges were calculated and introduced in the present work.

Wind is an important factor affecting the observed sea level. This effect varies from one location to another, and depends largely on the morphometry and the position of the location itself. This paper investigates the relationship between the variations in the observed sea level at Alexandria Western Harbour and Abu-Qir Bay, of different morphometry, along Alexandria coast, and the wind pattern over the city. Simultaneous data sets of hourly sea level records at the two locations and of hourly measured wind over Alexandria from 01.01.2005 to 31.12.2006 are used. The WORLD TIDES package is used for a full sea level analysis. The wind pattern is described, and both wind rose and frequencies are also produced. Results reveal that tides in Abu Qir Bay can be classified as steric meteorological tides; greatly affected by the wind pattern than the astronomical impact. This is mainly attributed to the morphometry and open location of the Bay. In Alexandria Western Harbour, on the other hand, tides can be classified as astronomical tides mainly affected by the sheltered location and the constructions of the Harbour, which diminish the effect of the wind and, meanwhile, increase the impact of the celestial bodies on the recorded sea level.

A one decade (1996–2005) of daily sea level records at Alexandria has been used to calculate both astronomical tide and surge elevations. The tidal harmonic constituents have been constructed using the T_TIDE program. Surge elevations have been calculated by subtracting the astronomical height from the observed sea level. The type factor of the tidal cycle at Alexandria has been calculated and specified the mixed mainly semidiurnal tide. The minimum annual Mean Sea Level (MSL) was 48.62 cm, while the maximum was 52.96 cm. The MSL over the study period is 50.67 cm. Thirty-five tidal constituents have been produced based on the present data. Both the Mm (Lunar monthly) and the Msf (Lunisolar synodic fortnightly) constituents in the present study have the largest constituent amplitudes, being 2.03 for the former and 7.06 for the later. The surge height over the study period varied between 14.64 and 87.15 cm, with an average of 50.66 cm. The results of the present research show that astronomical tide contributes with 0.005–37.63% while, surge contributes with 62.37–99.995% in the observed sea level.