How can we measure the coastal currents of Sharm El-Sheikh?

1. Where is Sharm El-Sheikh?

Sharm El-Sheikh is a world-renowned coastal city located at the southern tip of the Sinai Peninsula in Egypt. It lies along the Red Sea and is a prime destination for tourists from around the globe.

The city is blessed with a spectacular natural setting. It represents both sandy beaches and rocky coves along its coastline, while in the distance as far as the eye can view lie the crystal waters of the Red Sea. The Red Sea near Sharm El-Sheikh hosts a wide variety of marine life. The place boasts coral reefs, known throughout for their brilliance, that support an underwater world that is just so colorful and dramatic in detail. These reefs support an enormous variety of fish species, from small, bright-colored tropical fish to larger predators. Events of sea turtles, dolphins, and other marine mammals are not so rare either in these waters.

At the human level, Sharm El-Sheikh is a busy tourist city. There are numerous water sports such as diving, snorkeling, and water skiing that take place within the city. The city also boasts of an active night life with a number of luxury resorts and hotels. The economy is therefore heavily reliant on tourism, with a great number of people employed in the hospitality and service sectors.

The hydrographic profile of the adjacent Red Sea waters is peculiar. The sea in this area is influenced by the larger circulation patterns of the Red Sea. The narrow straits and gulfs in the region may contribute to controlling the flow of water, while the local topography-which includes the general shape of the coastline and the underwater mountains and valleys-also influences the movement of water.

2. What is the status of the coastal currents off Sharm El-Sheikh?

The coastal currents off Sharm El - Sheikh are under the influence of more factors, among which are large-scale circulation features of the Red Sea. It is connected with the Indian Ocean by means of the Bab el-Mandeb Strait, and the inflow of water through the strait determines the total movements of water in the Red Sea and, thus, the coastal currents around Sharm El-Sheikh. Thermohaline circulation, which is caused by differences in temperature and salinity, impacts current patterns.

Wind patterns play an important role. The winds over the Red Sea can push the surface currents through. As an example, in summer the northerly winds can force the surface water to take a specific direction which either enhances or hinders the natural flow of the coastal currents. Another essential factor is the topography of the sea floor around the coast of Sharm El - Sheikh. These underwater features include coral reefs, canyons, and shoals that make the water change direction and speed as it flows.

Also contributing is the tide: the pulling of the moon and sun on the sea raises and lowers the level through tidal currents. In these relatively narrow and complex coasts, as found near Sharm El­ Sheikh, this tidal current can interact with other factors in a complicated and dynamic pattern of water movement.

3. How to observe the coastal water flow of Sharm El-Sheikh?

Surface Drifting Buoy Method

The deployment of buoys on the surface of the water which are let to drift on the current. In utilizing satellite-based tracking systems, or any other positioning system methods, buoy movement over a determined period will yield data showing the direction and speed in which surface currents are running. However, this technique again provides surface data mostly; it will hardly give comprehensive records of currents at various levels deep inside.

Moored Ship Method

In this method, a ship is moored within the coastal zone area. Onboard instruments are used to measure the characteristics of water flow in its vicinity. Though this may be quite accurate in a small area over which measurements are taken around the ship, there are a few disadvantages. The mere presence of the ship might affect the local flow while spatial coverage will be limited to areas surrounding where the ship was moored.

Acoustic Doppler Current Profiler Method

Acoustic Doppler Current Profiler (ADCP), in comparison, is more modern and also a rather effective means for the measurement of coastal currents. It relies on the acoustic waves to measure water velocity at different depths. The output from ADCP current meter provides the current profile from surface to a definite depth by emitting an acoustic pulse and analysing the reflected signal with Doppler shift. This would give a better understanding of the vertical structure of the coastal currents near Sharm El - Sheikh and would be less affected by external factors such as the ship's influence.

4. How do ADCPs using the Doppler principle work?

ADCPs work on the principle of the Doppler effect. They send acoustic signals into the water. When those signals encounter moving particles in the water-sediment, plankton, or small organisms-the frequency of the reflected signal changes. The frequency shift is proportional to the velocity of the moving particles.

The ADCP current profiler operates with several transducers that emit and receive acoustic signals in different directions. By measuring the Doppler shift in multiple directions, it can calculate the velocity components of the water in three-dimensional space. These velocity components are integrated to find the overall flow velocity and direction of water at different depths.

5. What's needed for high-quality measurement of Sharm El-Sheikh coastal currents?

Such measurements of coastal currents around Sharm El-Sheikh require equipment made with high-quality and reliable material that can resist the aggressive marine environment, such as corrosion due to seawater, or even high pressure when situated at deeper levels; also, a small-sized, light device is desirable because of the ease in deploying these in buoys or on small boats or on fixed platforms.

Low power consumption is desirable, especially in the case of long-term monitoring. The devices will have to operate based on limited power sources: a battery or solar panels. Cost-effectiveness is very relevant. In order for the measurements to be able to be carried out on a large-scale basis along the coast of Sharm El-Sheikh, the equipment should not be expensive.

As for the casing of the ADCP profiler, titanium alloy is an excellent material. The corrosion resistance of the titanium alloy is very high, which is absolutely necessary for these corrosive seawaters. It has a very good strength-to-weight ratio, giving it strength while keeping the weight relatively low. This material will definitely help to bear all the pressure at greater depth, maintaining the reliability of the equipment during deep-water measurements.

6. How to Choose the Right Equipment for Current Measurement?

According to Use Purpose

• Ship-borne ADCP: This would be the suitable option if the intention is to measure the currents while the ship is in motion or during a specific voyage along the coast of Sharm El - Sheikh. It is installed on the hull of the ship and collects data while the ship is sailing.
• Bottom-mounted ADCP: For long - term, fixed - location monitoring of the currents near the seabed, a bottom - mounted ADCP is the way to go. It can be firmly placed on the seafloor to provide accurate information about the water flow close to the bottom.
• Buoy-mounted ADCP: When the goals include measuring currents at greater depths in a more flexible manner and over a greater area, a buoy-mounted ADCP is preferred. It will be able to drift, to some extent, along with the currents and gather information as it moves.

By Different Frequencies

• ADCP 600kHz is suited to up to 70m depth of water. It allows high-resolution measurements suitable for the relatively shallow coastal waters of Sharm El-Sheikh.
• ADCP with 300kHz is used for depths ranging from 70m to 110m. It gives a balanced measurement range and accuracy suitable for medium-depth waters.
• A 75kHz ADCP can go as deep as 1000m and therefore is recommended for deeper waters. This will give it the ability to penetrate deeper and provide more reliable current data in the deeper parts of the coastal area around Sharm El - Sheikh.

There are well-known ADCP brands such as Teledyne RDI, Nortek, and Sontek. However, a Chinese brand, China Sonar PandaADCP, is also worth considering. It is made of all - titanium alloy, which provides excellent durability. It also offers an impressive cost - performance ratio. You can find more information on its website: https://china-sonar.com/.

Here is a table with some well known ADCP instrument brands and models.