JKAU: Mar. Sci., Vol. 29 No. 1 pp: 21-36 (1441 A.H. 2019 /A.D ) DOI :10.4197/Mar.29-1.2

Characteristics of the Relative Sea Level in Abu-Qir Bay, ,

Mohammed Ahmed Said, Tariq EL-Gesiry, Zainab Morsi National Institute of Oceanography and Fisheries

Abstract. hourly water level variations at Abu-Qir Bay were studied over 21 years. The levels were highly seasonal with a mean of 0.47m, and a rising rate of 6mm/yr. Tides are of semidiurnal type and of low amplitudes. No extreme sea level year was detected. Statistical analysis of surge heights was obtained. The estimation of flooding risks was determined. The design risk factor and return values of important water levels were calculated. An empirical relationship for the different water levels frequency of occurrence stated that the high water level of 3m might be exceeded once in 100 years. Keywords: Relative sea level, Abu-Qir Bay, Astronomical tides, Surges, Return periods, Flooding risk

Introduction environmental pressures. Egypt’s The sea level variations along the Egyptian Mediterranean coast and the Delta have Mediterranean coast have been the core of been identified as highly vulnerable to climate many researches, e.g. Moursy, 1989; Moursy, change induced SLR (UNDP, 2014). Dasgupta 1992; Moursy, 1993; Moursy, 1994; Moursy, et al. (2009) ranked Egypt in the top ten most 1998; Tayel, 2008; Hussein et al., 2010; Saad impacted countries (out of 84 developing et al., 2011; El-Geziry and Radwan, 2012; coastal countries considered world-wide) for Maiyza and El-Geziry, 2012; Said et al., 2012; population potentially displaced due to a 1m Radwan and El-Geziry, 2013; El-Geziry, SLR. Alexandria was ranked 11th in terms of 2013; El-Geziry and Said, 2014. All concluded population exposed to coastal flooding in that the tidal variations along the Egyptian 2070s (El-Deberky and Hunicke, 2015). Mediterranean coast are in order of a few The linear trend of increase in the sea level centimeters, and are of the semidiurnal type. along the Egyptian Mediterranean was The coastal zone of the Egyptian previously calculated to range between 0.15 is exposed to multiple cm/yr to 0.30 cm/yr (El-Fishawi and Fanos,

21 22 Mohammed Ahmed Said, Tariq EL-Gesiry, Zainab Morsi

1989; Frihy, 1992;; Frihy, 2003; Said et al., Alexandria, and spots light on the main 2012; Shaker, et al., 2011 and Maiyza and El- statistical characteristics of the sea level; Geziry, 2012). representing the risk factors and the regional Radwan and El-Geziry (2013) investigated the flood factor of the Bay. statistical properties of surge off Alexandria Data and Methods of Analysis over one decade (1996-2005). Their results Abu-Qir Bay (Fig. 1) is a semi-circular basin revealed that the 51-60 cm surge heights are lying 35 km east of Alexandria City between the most frequent to occur over the latitudes 31° 16' and 31° 28' N and longitudes investigated period, while the 81-90 cm are the 30° 03' and 30° 22' E. The bay is a shallow lowest. On seasonal basis, the calculations basin with an average depth of less than 10 m showed that for both the highest and the lowest and most of the bay has a gentle slope with a 10% of occurrence, the summer season maximum depth of about 22 m. The coastline recorded the highest and lowest events, with of Bay extends for about 50 km 163 and 0, respectively. The winter season between the headlands of Abu Qir in the showed only 55 high events and 184 low ones. southwest and in the northeast Both spring and autumn surge heights show (Abdallah et al., 2007; Zakaria, 2007). The moderate occurrence for both the highest and surface area of the bay is about 360 km2 and the lowest occurrence percentage. its water volume is 4.3 km3 (Said et al., 1995). Said et al. (2012) calculated the probable The Bay is in contact with Lake Edku through maximum expected water level condition Boughaz Meadeya. The Bay is considered one (extreme return period) off Alexandria to reach of the very sensitive zones within the eastern 165 cm once in 100 years and 181 cm once in Mediterranean Sea to the relative SLR. Wave 500 years, and accordingly they calculated the movement, circulation pattern and sea level design life time of coastal structure and the variations in Abu-Qir Bay have been risk for the 80 cm level off Alexandria. A previously investigated, e.g. El-Gindy, 1988; severe climate event was demonstrated by a El-Gindy et al., 1988; Said et al., 1995; strong storm that hit the Mediterranean coast Abdallah et al., 2007; Said et al., 2012; El- of Egypt on 11 December 2010, associated Geziry, 2013; El-Geziry and Said, 2014. with peak wind speed of more than 60 km/hr The present data set of hourly sea level is (Said et al., 2012). This storm caused coastal taken from an automatic tide gauge fixed in flooding in Alexandria with a surge exceeding Abu-Qir Bay. The position of the instrument is 1 m. This value is much higher than the typical 31°19.54’ N; 30°04.5’ E (Fig. 1). The data are values of storm-surge reported offshore the referred to the zero level of the instrument, and Nile delta coast (40 to 50 cm). Fortunately, the cover 21 years from January 1990 to storm only caused partial damage of some December 2010, which means a total of coastal structures and modest flooding of 184080 hours. However, there are gaps in the lowlands within Abu-Quir bay, east of recorded data and the actual data in hands are Alexandria. El-Deberky and Hunicke (2015) only for 174119 hours (94.58%). The missed succeeded to determine the four most data, on the other hand, represent 5.42 %. vulnerable areas to the risk of the relative SLR Statistically speaking, this missed set does not and inundation along the Egyptian affect the data quality to proceed for the Mediterranean Coast, among which is Abu-Qir proposed investigation. bay. The present paper investigates the relative sea level variations in Abu-Qir Bay, east of Characteristics of the Relative Sea Level in Abu-Qir Bay, Alexandria, Egypt 23

Figure (1) with the location of the automatic tide gauge

In the present work, the sea level components φn is the nodal phase of harmonic component; (astronomical tide and surge elevations) are and produced using the WORLD TIDES® package kn is the phase of nth constituent for the time working under the MATLAB® environment origin in use (Boon, 2004). The package is used for the The method used by WORLD TIDES® to analysis and prediction of water levels. It analyze a water level time series is commonly permits quick separation of a time series of known as Harmonic Analysis Method of Least water level measurements into its tidal and Squares (HAMELS). This is a simple but non-tidal components using a selective least powerful means of obtaining tidal constituent squares harmonic reduction employing up to amplitude (An) and phase (kn), needed for tidal 35 tidal constituents. WORLD TIDES® is predictions using Equation (1). principally based on the concept of the ability The five main tidal components (O1, K1, N2, of expressing the tidal amplitudes at any M2 and S2) are the default tidal constituents location as the sum of all the harmonic produced by the software. These are produced components, as in the following equation: for the present work.  2  Using the output from this harmonic tidal (t) ZO  fn An cos t n  kn  (1) analysis, the type of the tidal cycle in Abu-Qir   T  n  n  Bay is determined using the following :(Where، constituent factor (Pugh, 2004 η(t) is the vertical displacement of the sea FF = (HO1 + HK1) / (HM2 + HS2) (2) ،surface as a function of time (m); Where Zo is the Mean Sea level (MSL); HO1 is the tidal height of the principal lunar ؛(fn is lunar node factor for nth constituent; diurnal constituent (m An is the amplitude of a harmonic component HK1 is the tidal height of the luni-solar diurnal ؛(m); constituent (m) Tn is the period of a harmonic component (s); HM2 is the tidal height of the principal lunar semidiurnal constituent (m); and

24 Mohammed Ahmed Said, Tariq EL-Gesiry, Zainab Morsi

HS2 is the tidal height of the principal solar with which sea levels and risk may be semidiurnal constituent (m) expected to occur in the future. The general characteristics of water levels and Results astronomical tide for Abu-Qir Bay are Characteristics of Relative Sea Level at obtained with the principal features of the Abu-Qir Bay residuals. The hourly sea level varied between Since the knowledge of the expected sea state 0.01 m and 1.0 m above the zero level of the is required for the design and for the safety of instrument (Fig. 2), i.e. 0.99 m tidal range, life at sea, the aim of this study is to get a with a MSL of 0.47 m. better evaluation of forecasting and knowing the frequency and the probability distribution,

Figure (2) Hourly Sea Level Recorded in Abu-Qir Bay from January 1990 to December 2010 Figure (3) shows the frequency of occurrence respectively. The probability of occurrence of of the recorded sea level over the period of different water levels is presented and the most investigation. This varied between 6 hourly pronounced frequency was concentrated in the events (0.003%) and 30577 hourly events level of 0.5 m and diminished rapidly in the (16.61%) for the 1 m and 0.5 m water levels, levels less than 0.05 m and more than 0.85 m.

Figure (3) frequency of occurrence of the recorded sea level over the period of investigation The monthly mean water level pattern of Abu- August shows somewhat high water level due Qir Bay (Fig. 4) shows seasonal trend, where to the atmospheric pressure system. The low levels occur in spring months (March and highest monthly mean water level was 0.52 m April) and higher one in winter (November in November and the lowest was 0.40 m in and December), while the summer month of April. Characteristics of the Relative Sea Level in Abu-Qir Bay, Alexandria, Egypt 25

Figure (4) Monthly MSL at Abu-Qir Bay over the study period Variations in the annual mean water levels are shown in Figure (5). In spite of the annual oscillation levels, there is an upward trend with a sea level rise of 6 mm/yr. more details about the annual water level variations are given in Table (1), where it revealed that the annual MSL ranged from 0.35 m in 1990 and 0.55 m in 2004.

Figure (5) Annual MSL at Abu-Qir Bay during the study period

Figure (6) Tidal Elevations at Abu-Qir Bay over the period January 1990-Decemeber 2010, using the World Tides® Package

26 Mohammed Ahmed Said, Tariq EL-Gesiry, Zainab Morsi

Table (1) The main statistical characteristics of the annual relative sea level in Abu-Qir Bay during the period 1990-2010 Min. (m) Max. (m) Range (m) Mean (m) Variance Standard Deviation 1990 0.01 0.71 0.70 0.35 0.017 0.129 1991 0.01 0.77 0.76 0.40 0.016 0.128 1992 0.01 0.78 0.77 0.42 0.021 0.145 1993 0.02 0.74 0.72 0.39 0.016 0.127 1994 0.03 0.79 0.76 0.45 0.013 0.112 1995 0.03 0.79 0.76 0.45 0.013 0.112 1996 0.15 0.88 0.73 0.49 0.012 0.112 1997 0.04 0.82 0.78 0.50 0.013 0.113 1998 0.07 0.77 0.70 0.47 0.009 0.096 1999 0.08 0.81 0.73 0.43 0.008 0.088 2000 0.13 0.80 0.67 0.44 0.007 0.085 2001 0.20 0.79 0.59 0.54 0.010 0.098 2002 0.14 0.93 0.79 0.52 0.011 0.106 2003 0.16 0.77 0.61 0.49 0.007 0.085 2004 0.26 0.85 0.59 0.55 0.008 0.091 2005 0.22 0.80 0.58 0.52 0.007 0.084 2006 0.20 0.89 0.69 0.54 0.009 0.093 2007 0.11 0.85 0.73 0.50 0.013 0.114 2008 0.18 0.82 0.64 0.51 0.007 0.085 2009 0.05 1.00 0.95 0.47 0.020 0.142 2010 0.18 0.96 0.78 0.53 0.013 0.115

The Astronomical Tides The results of the present HAMELS analysis Bay is 0.21, which clearly reflects the show that over the study period, the hourly semidiurnal type of tides in the Bay. This astronomical tidal elevations at Abu Qir Bay semidiurnal type is also confirmed by the varied between 0.44 m and 0.51 m (Fig. 6), frequency periodogram of the tide cycles (Fig. with a mean tide level (MTL) of 0.47 m. The 7). calculated FF using Equation (2) for Abu-Qir

Characteristics of the Relative Sea Level in Abu-Qir Bay, Alexandria, Egypt 27

Figure (7) Tidal Frequency Periodogram at Abu-Qir Bay Using the World Tides® package, the amplitudes and the phases of the main five tidal constituents for the Bay are obtained (Table 2). Table (2) Tidal constituents at Abu-Qir Bay Tidal constituents Amplitude (m) Phase (°) O1 0.002 238.53 K1 0.004 320.62 N2 0.003 194.87 M2 0.016 251.47 S2 0.013 306.62 The tidal characteristics of the Bay are produced in Table (3), where it shows that 0.07 m is the highest range of tide, with spring and neap ranges of 0.05 m and 0.01 m, respectively, which is relatively small compared to Alexandria tidal range of 0.28 m (Moursy, 1998).

Table (3) Tidal Characteristics of the Relative Sea Level at Abu-Qir Bay

Highest Astronomical Tide (HAT; m) 0.51 Lowest Astronomical Tide (LAT; m) 0.44 Highest range of tides (m) 0.07 Mean High Water Spring (MHWS; m) 0.50 Mean Low Water Spring (MLWS; m) 0.45 Mean Spring Range (m) 0.05 Mean High Water Neap (MHWN; m) 0.48 Mean Low Water Neap (MLWN; m) 0.47 Mean Neap Range (m) 0.01

The highest frequency distribution of the astronomical tides (Fig. 8) is concentrated in the level of 0.48 m.

28 Mohammed Ahmed Said, Tariq EL-Gesiry, Zainab Morsi

Figure (8) Frequency of occurrence of the astronomical tides at Abu Qir Bay The Residuals In Abu Qir Bay, the residual water level events (0.05 m; 16.32%). The highest (Difference between observed and frequency percentages of residuals are astronomical sea levels) is shown in Figure concentrated between the residual levels -0.05 (9), which shows that the residuals varied m and +0.10 m (Fig. 10). While the negative between -0.49 m and +0.51 m over the period one represents 11.68%, the positive 0.05 m 1990-2010. The frequency of their occurrence and 0.10 m represent 16.32% and 14.6%, revealed that they varied between one hourly respectively. event (0.55m; 0.001%) and 30044 hourly

Figure (9) Surge elevations at Abu-Qir Bay over the period of investigation Characteristics of the Relative Sea Level in Abu-Qir Bay, Alexandria, Egypt 29

Figure (10) Frequency of occurrence of different surge intervals at Abu-Qir Bay over the study period Extreme Water Levels: over the period (1990-2010), but still has In the design of coastal structures or coastal dangerous high water level. defense, consideration must be given to know The frequency of abnormal high sea levels the more effective water levels that are likely along the west coast of Great Britain was to occur. The coastal flooding during these computed by Lennon (1963), in order to high levels or severe surges is a major problem extrapolate the trend of frequencies necessary in bays. for determining the optimum height for sea Extreme water level events typically result coast protection. from high water level on spring tides and In this method, the logarithmic scale is used storm surges. Since tides in Abu-Qir Bay are for the average number of cases per year generally weak, the high water level variations (n/N), where (n) is the number of cases during and its impacts are brought about by the high the period of records for which the water level residual events. Even moderate rise in the has been attained or exceeded, (N) is the total residuals will have some implications for the period of water level records expressed in coastal zone in the Bay. years, which is 21 years in the present study. According to Ekman (1996), an extreme sea The result is the empirical relation for the level year can be defined as a year when the frequency of occurrence of water level and the annual mean deviates from the regression line height value (H). The relation obtained by more than twice the standard deviation, expressed by: provided a series is reasonably distributed (4) (3) Therefore, for the present study, the empirical Where, relationship for the frequency of water heights |L| is the yearly deviation; and at Abu-Qir Bay and the water level (H) is σ is the total standard deviation determined by the following Equation: According to this definition, the present data set revealed no extreme year for Abu-Qir Bay (5)

30 Mohammed Ahmed Said, Tariq EL-Gesiry, Zainab Morsi

The linear presentation of this empirical relationship is shown in Figure (11).

Figure (11) Frequency of occurrence of water levels and water height (H) values

Accordingly, the water heights (H) to be exceeded once in 10, 20, 30, 40, 50, 75, 100, 150 and 200 years are given in Table (4). Table (4) Frequency of occurrence of abnormal water heights (H) years 10 20 30 40 50 75 100 150 200 H (m) 2.4 2.6 2.7 2.8 2.8 2.9 3.0 3.1 3.2 The same method is applied for the frequency of both positive (Eq. 6) and negative (Eq. 7) distribution of hourly surge heights for Abu- surges and the surge value (S). Qir Bay. The result is two empirical (6) relationships for the frequency of occurrence (7) The linear presentation of the frequency of both positive and negative surges, with the surge height values are shown in Figure (12).

Figure (12) Frequency of occurrence of positive surge (a) and negative surge (b) and the surge values On basis of the two Equations for Abu-Qir Bay, the positive and negative surges contribution to be exceeded once in 10, 20, 30, 40, 50, 75, 100, 150 and 200 years are given in Table (5).

Characteristics of the Relative Sea Level in Abu-Qir Bay, Alexandria, Egypt 31

Table (5) Frequency of occurrence of abnormal positive and negative surges 10 20 30 40 50 75 100 150 200 +ve surge (m) 0.60 0.64 0.66 0.68 0.69 0.71 0.73 0.75 0.76 -ve surge (m) -0.79 -0.84 -0.87 -0.89 -0.91 -0.94 -0.96 -0.99 -1.01

Return period and risk of water levels at The risk of different water levels in Abu-Qir Abu-Qir Bay Bay is calculated by the Equation: The studies on the probabilities of extreme sea (8) level in Abu-Qir Bay, and the prediction of Where Q(z) is the probability of exceeded flooding risks are necessary for the design of level (m); and TL is the design life time coastal structures. On basis of hourly water (years). The latter is plotted in Figure (13) for levels in Abu-Qir Bay over 21 years (1990- the lowest 0.20 m and the highest 0.75 m 2010), the probability of occurrence of the water levels, being the most two levels close to different water level intervals are determined a 100 years return period. The expected design and shown in Table (6), which shows that the risk life time for each water level interval, highest probabilities are concentrated in the using Equation (8), is shown in Table (6). levels between 0.45 m and 0.60 m, while the lowest are above the level of 0.85 m. According to these probability distribution the return period of each level is determined (Table 6).

Figure (13) Design Risk Curve for the lowest (0.20 m) and highest (0.75 m) water levels at Abu-Qir Bay during the study period

32 Mohammed Ahmed Said, Tariq EL-Gesiry, Zainab Morsi

Table (6) Return Periods and Expected Design Risk Life Time at Abu-Qir Bay using Equation (8) SL intervals (m) Probability (Q(z)) Years of the Design Life Time (TL) Return Period (years) 10 20 50 100 200 300

0.05 0.002 0.020 0.040 0.097 0.185 0.336 0.458 489.6

0.1 0.003 0.028 0.055 0.131 0.246 0.431 0.571 355.4

0.15 0.006 0.060 0.116 0.266 0.461 0.710 0.844 162.2

0.2 0.012 0.112 0.211 0.447 0.695 0.907 0.972 84.8

0.25 0.021 0.195 0.352 0.661 0.885 0.987 0.998 46.7

0.3 0.035 0.301 0.511 0.833 0.972 0.999 1.000 28.5

0.35 0.065 0.489 0.739 0.965 0.999 1.000 1.000 15.4

0.4 0.102 0.660 0.884 0.995 1.000 1.000 1.000 9.8

0.45 0.135 0.765 0.945 0.999 1.000 1.000 1.000 7.4

0.5 0.166 0.837 0.974 1.000 1.000 1.000 1.000 6.0

0.55 0.152 0.807 0.963 1.000 1.000 1.000 1.000 6.6

0.6 0.124 0.733 0.929 0.999 1.000 1.000 1.000 8.1

0.65 0.070 0.514 0.764 0.973 0.999 1.000 1.000 14.4

0.7 0.036 0.308 0.521 0.841 0.975 0.999 1.000 27.7

0.75 0.010 0.107 0.203 0.433 0.679 0.897 0.967 88.5

0.8 0.004 0.041 0.081 0.190 0.344 0.569 0.717 237.8

0.85 0.001 0.013 0.026 0.063 0.122 0.230 0.324 767.0

0.9 0.000 0.004 0.008 0.020 0.040 0.079 0.117 2422.1

0.95 0.000 0.002 0.003 0.008 0.015 0.030 0.045 6574.3

1 0.000 0.000 0.001 0.002 0.003 0.006 0.010 30680.0

Discussion and Conclusion Bay area has been subjected to physical, Abu-Qir Bay is a semi-circular basin lying 35 chemical and biological studies. km east of Alexandria City. The land border of The present paper aimed at investigating the the Bay comprises many important agricultural relative sea level variations in Abu-Qir Bay and industrial zones. The Bay is considered and spot light on the main statistical one of the very sensitive zones within the characteristics of the sea level; representing eastern Mediterranean Sea to the relative SLR. the risk factors and the regional flood factor of Due to its socioeconomic importance Abu-Qir the Bay. The study was based on hourly data of sea level over 21 years from January 1990 to December 2010. Characteristics of the Relative Sea Level in Abu-Qir Bay, Alexandria, Egypt 33

On basis of water level data at Abu-Qir Bay Statistical estimation of surge heights revealed for the period 1990-2010, the general pattern that the highest frequencies of surge illustrated that the water levels are highly occurrence are concentrated at levels between seasonal in nature, where high levels are in -0.05 m and +0.15 m. winter and summer, and low ones in spring Coastal planners have to include estimate of season, with a mean water level of 0.47 m. flooding risk into their designs, and allow This was previously calculated for Abu-Qir measures of protection against expected Bay to be 0.52 m (El-Geziry, 2013) and this is extreme sea conditions during the lifetime of in agreement with the general MSL off any proposed coastal development. So, Alexandria coasts of 0.40 m for the period knowledge of risk of flooding in the Bay is 1944–1989 (Frihy,1992), 0.46 m in 1986 necessary so that decision can be made on (Moursy, 1998); 0.506 m for the period 1997– where to protect. According to Ekman theory, 2004 (Hussein et al., 2010), 0.52 m for the no extreme sea level year appeared during the period 1995–2005 (Saad et al., 2011); 0.48 m study period. However, statistical analysis of for the period 1974–2006 (Said et al., 2012) surge heights showed that the positive surge and 0.51 m for the period 1996-2005 (El- can exceed 0.73 m once in 100 years, while it Geziry and Radwan, 2012). The probability of is -0.96 m for the negative surge. Also, the sea occurrence of different water levels is level can exceed 3 m once in 100 years. The presented and the most pronounced frequency regional design risk factor of 0.80 m water was concentrated in the level of 0.50 m, and level was 0.72 for a design lifetime of 300 diminishes at the levels more than 0.80 m and years, while it was 0.34 for 100 years. The less than 0.10 m. The highest level obtained return period of the water levels of 0.75 m, was 1.0 m, while the lowest was 0.01 m. The 0.80 m and 0.85 m are 88, 238 and 767 years, relative sea level in the present work described respectively. However, for a good design, the a rising trend of 6 mm/yr. The relative sea design level must have a return period that level at the Mediterranean coasts is rising at considerably exceeds the expected lifetime of rates of 1.0 mm/yr (Marseille), 1.3 mm/yr structure. (Genova/Trieste), 2.6 mm/yr (Venice), which References is close to the global average (Liebsch et al. Abdallah, M.A., Sharaf El-Din, S.H. and 2002). The present rate of increase is thus Shereet S.M., 2007. Analysis of wave higher and is even higher than the rate observations and wave transformations in previously calculated off Alexandria Coast: Abu-Qir Bay, Egypt. Egyptian Journal of 1.2 mm/yr ; 3 mm/yr (Said et al., 2011); 1.7 Aquatic Research, 32(1): 22-33. mm/yr (Shaker et al., 2011); 2.1 mm/yr Boon, J., 2004. Secrets of the Tide: Tide and (Maiyza and El-Geziry, 2012). This upward Tidal Current analysis and Predictions, Storm trend will increase the impact of extreme surges and Sea Level Trends. Horwood events and consequently shorten their return Publishing, Chichester, UK, 210p. period. Dasgupta, S., Laplante, B., Murray, S. and The water level records demonstrated that the Wheeler D., 2009. Sea-Level Rise and Storm tide is mainly semidiurnal with a mean range Surges: A Comparative Analysis of Impacts in of 0.47 m. The range of spring tides is on Developing Countries. The World Bank, average of 0.05 m and reduced to 0.01 m Policy Research Working Paper, WPS4901, during neap tides. 41p.

34 Mohammed Ahmed Said, Tariq EL-Gesiry, Zainab Morsi

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36 Mohammed Ahmed Said, Tariq EL-Gesiry, Zainab Morsi

ﺧﺎﺋ ﻣ ﺳﺢ اﻟ اﻟﻲ ﻓﻲ ﺧﻠﺞ أﺑﻲ ﻗ، اﻹﺳرﺔ، ﻣ

ﻣ أﺣ ﺳﻌ، ﺎرق ﻣ اﻟ، ز ﻋ اﻟﻌ ﻣﺳﻲ ﻣﻌﻞ ﻋﻠم اﻟﺎر اﻟﺔ، ﺷﺔ اﻟﺔ اﻟﺔ اﻟﻌﻬ اﻟﻘﻣﻲ ﻟﻌﻠم اﻟﺎر واﻟﺎﯾ، اﻹﺳرﺔ، ﻣ

ﻣﻠ. ﺗ دراﺳﺔ اﻟﻐات ﻓﻲ ﻣ اﻟﺎﻩ ﻓﻲ ﺧﻠﺞ أﺑ ﻗ ﻋﻠﻰ ﻣ 21 ﻋﺎﻣﺎ. وﺎﻧ اﻟﻐات ﻓﻬﺎ ﻣﺳﺔ ﺳ ﻋﺎم 0.47م، وﻌل ارﺗﻔﺎع 6ﻣﻠﻠ/ﺳﺔ. اﻟ واﻟر ﻓﻲ ﺧﻠﺞ أﺑﻲ ﻗ ﻣ اﻟ ع اﻟﻒ ﯾﻣﻲ وذو ﺳﻌﺎت ﻣﻔﺔ. ﻟ ﺗﻬ اﻟﺎﺋﺞ وﺟد ﻋﺎم ﻣد ﻷ ﻣ ﺳﺢ اﺳﺎﺋﻲ. ﺗ ﻋﻞ اﻟﻠﻞ اﻹﺣﺎﺋﻲ ﻻرﺗﻔﺎﻋﺎت اﻟﻌاﺻﻒ ،ﻛﻟ ﺗ ﺗﻘﯾ ﻣﺎ اﻟﺎﻧﺎت ﻘﺔ اﻟﻠﺞ. ﺗ ﺣﺎب ﻣﻌﺎﻣﻞ ﺧ ﺗ اﻟﺂت و اﻟار ﻟﺎت اﻟﺎﻩ اﻟﻬﺎﻣﺔ. وأوﺿ ﻋﻼﻗﺔ ﺗﺔ ﻟﺎت ﻣﻠﻔﺔ ﻣ ﺗاﺗ ﺣوث ا رﺗﻔﺎع ﻓﻲ ﻣ اﻟﺎﻩ أن ﻣ اﻟﺎء ﻗ ﯾﻠﻎ أو ﯾﺎوز 3 أﻣﺎر ﻣ ة واﺣة ﻓﻲ 100 ﺳﺔ.